Canine parvovirus 2(CPV-2)is a highly contagious virus in dogs that typically causes hemorrhagic enteritis and a high mortality rate in unvaccinated puppies.The genetic variability and antigenic diversity of CPV-2 hin...Canine parvovirus 2(CPV-2)is a highly contagious virus in dogs that typically causes hemorrhagic enteritis and a high mortality rate in unvaccinated puppies.The genetic variability and antigenic diversity of CPV-2 hinder its efective prevention of infection by vaccination.To investigate the epidemiology and genetic characteristics of CPV-2 in China,rectal swabs from afected dogs were collected from diferent animal clinics in Kunshan from 2022 to 2023.Preliminary detection and capsid gene sequencing of CPV-2 were performed using previously described primers and protocols.The overall detection rate for CPV-2 was 16.5%(33/200).A signifcant association was found between the CPV-2-positivity and clinical signs,age,breed and vaccination status.Sequence analysis revealed the presence of CPV-2c genotypes in all positive samples,which were genetically similar to other Asian CPV-2c strains.Notably,four key mutations(A5G,F267Y,Y324I and Q370R)were detected in all isolates,and one novel mutation(I447M)was detected in three CPV-2 isolates.These mutations in the CPV-2 strains could impact vaccine efcacy and the efectiveness of the virus immune evasion.Surprisingly,no recombination events were observed between the identifed CPV-2c strains and reference strains from China.Our data revealed that amino acid residues 324,426 and 440 of VP2 may under strong selection pressure.This pattern of genetic variation in the CPV-2 lineage warrants continuous laboratory-based surveillance programs in other parts of China to better understand the pattern of seasonal distribution and association between emerging genotypes and the intensity of disease severity.展开更多
Feline panleukopenia virus(FPV)is a single-stranded DNA virus that can infect cats and cause feline panleukopenia,which is a highly contagious and fatal disease in felines.The sequence of FPV is highly variable,and mu...Feline panleukopenia virus(FPV)is a single-stranded DNA virus that can infect cats and cause feline panleukopenia,which is a highly contagious and fatal disease in felines.The sequence of FPV is highly variable,and mutations in the amino acids of its capsid protein play crucial roles in altering viral virulence,immunogenicity,host selection,and other abilities.In this study,the epidemiology of FPV was studied using 746 gastrointestinal swab samples derived from cats that presented gastrointestinal symptoms specifcally,diarrhea or vomiting during the period spanning from 2018 to 2022.The overall prevalence of FPV-positive patients among these samples was determined to be 45.4%.Capsid(virion)protein 2(VP2)gene of each FPV-positive sample was sequenced and amplifed,yielding 65 VP2 sequences.Among them,six VP2 gene sequences were detected in the majority of the samples test positive for FPV,and these positive samples originated from a diverse range of geographical locations.These isolates were named FPV-6,FPV-10,FPV-15,FPV-251,FPV-271 and FPV-S2.Additionally,the substitution of Ala300Pro(A300P)in VP2 was detected for the frst time in feline-derived FPV(FPV-251).FPV-251 isolate,with this substitution in VP2 protein,exhibited stable proliferative capacity in Madin-Darby canine kidney(MDCK)cells and A72 cells.FPV-271 was selected as the FPV control isolate due to its single amino acid diference from VP2 protein of FPV-251 at position 300(FPV-271 has alanine,while FPV-251 has proline).After oral infection,both FPV-251 and FPV-271 isolates caused feline panleukopenia,which is characterized by clinical signs of enterocolitis.However,FPV-251 can infect dogs through the oral route and cause gastrointestinal(GI)symptoms with lesions in the intestine and mesenteric lymph nodes(MLNs)of infected dogs.This is the frst report on the presence of an A300P substitution in VP2 protein of feline-derived FPV.Additionally,FPV isolate with a substitution of A300P at VP2 protein demonstrated efcient replication capabilities in canine cell lines and the ability to infect dogs.展开更多
Retroviruses have been proven to cause infections and diseases in a series of mammalian hosts but not in dogs.Then,this letter discussed the dog susceptibility to retrovirus infection,encompassing arguments to underst...Retroviruses have been proven to cause infections and diseases in a series of mammalian hosts but not in dogs.Then,this letter discussed the dog susceptibility to retrovirus infection,encompassing arguments to understand why dogs may have not been infected by retroviruses thus far.The potential resistance of retrovirus in dogs enables this provocative short communication to discuss this question,looking at some evolutive aspects.The lineage of canids has shown,throughout its evolutionary history,a smaller accumulation of retroviruses in canid genomes,classifed as endogenous retroviruses.In this context,the genomes of canids seem to ofer obstacles,which have been evolutionarily conserved,in the face of retroviral infection.展开更多
The aim of the present study was to compare the ixodicide efficacy of 1% permethrin applied as a shampoo-bath in single treatment and a combined formulation of 2% permethrin + 1% piperonyl butoxide applied as powder i...The aim of the present study was to compare the ixodicide efficacy of 1% permethrin applied as a shampoo-bath in single treatment and a combined formulation of 2% permethrin + 1% piperonyl butoxide applied as powder in a single treatment against Rhipicephalus sanguineus ticks, in naturally infested dogs. Eighteen adult cross-mixed dogs, harboring to at least 20 ticks/animal, were selected on pre-treatment live tick counts. On day 0, the dogs were then divided in 3 groups of 6 animals each, for treatment: Group 1 (G1) received 1% permethrin applied as shampoo-bath (approximately 10 ml/kg bw), according to label instructions. G2 was treated with 2% permethrin + 1% piperonyl butoxide applied as powder, and rubbed as massage on the body, as recommended by the producer. G3 served as a non-treated control. After the treatment, the dogs were checked out for live ticks counting on days 0, 1, 7, and 14. The ixodicide efficacy was assessed based on the percentage reductions of ticks on the days analyzed post-treatment, with respect to the untreated control. Results showed that permethrin alone removed ticks on 81%, 93.1% and 89.6% for days 1, 7 and 14, respectively. The combined formulation of 2% permethrin + 1% piperonyl butoxide exerted a better efficacy of 98.8, 97.7 and 97.0%, respectively. It is concluded that this combined formulation was highly effective at rapidly repelling and killing Riphicephalus sanguineus ticks on naturally infected dogs, showing a significant effect on days 1, 7 and 14 after tick exposure. The sustained high and quick level of efficacy of this combination may well interfere with the transmission of Riphicephalus sanguineus ticks. It is concluded that the sustained high level of efficacy of the permethrin + piperonyl butoxide combination may well exert an additive effect and could interfere with the transmission of Riphicephalus sanguineus ticks.展开更多
Activity 1.Think about the following questions and write down your answers before reading the text.1.Do you know some foods are toxic to dogs?2.What foods do you avoid giving your dog?
Chronic kidney disease is commonly diagnosed in dogs,and clinical signs may be aggravated when infected agents are involved.In this case report,33 dogs with chronic kidney disease were clinically evaluated and serolog...Chronic kidney disease is commonly diagnosed in dogs,and clinical signs may be aggravated when infected agents are involved.In this case report,33 dogs with chronic kidney disease were clinically evaluated and serologically tested for Leptospira spp.,Ehrlichia canis,and Anaplasma phagocytophilum.The seroprevalence for Leptospira spp.was 39.4%.The most frequent serovars found were Pyrogenes,Canicola,Bratislava and Australis,with serological titers between 1:100 to 1:800.Clinical signs included fever,depression,decreased body condition,vomiting and hema‑turia.Signifcant laboratory fndings were anemia,leukocytosis,thrombocytopenia,increased liver enzymes,urea and creatinine,hyperbilirubinemia and hyperphosphatemia.All leptospira seronegative dogs were positive for one or both monitored homoparasites(i.e.,E.canis and A.phagocytophilum);only three leptospira seropositive dogs were positive for one or both hemoparasites.Findings also suggest that endemic hemoparasites of dogs should be moni‑tored in dogs with a kidney condition for a better clinical picture of the patients and therapeutic approach.展开更多
Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synth...Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synthesize citrulline(the precursor of arginine)from glutamine,glutamate,and proline in the small intestine.Although most breeds of dogs have potential for adequately converting cysteine into taurine in the liver,a small proportion(1.3%-2.5%)of the Newfoundland dogs fed commercially available balanced diets exhibit a deficiency of taurine possibly due to gene mutations.Certain breeds of dogs(e.g.,golden retrievers)are more prone to taurine deficiency possibly due to lower hepatic activities of cysteine dioxygenase and cysteine sulfinate decarboxylase.De novo synthesis of arginine and taurine is very limited in cats.Thus,concentrations of both taurine and arginine in feline milk are the greatest among domestic mammals.Compared with dogs,cats have greater endogenous nitrogen losses and higher dietary requirements for many amino acids(e.g.,arginine,taurine,cysteine,and tyrosine),and are less sensitive to amino acid imbalances and antagonisms.Throughout adulthood,cats and dogs may lose 34%and 21%of their lean body mass,respectively.Adequate intakes of high-quality protein(i.e.,32%and 40%animal protein in diets of aging dogs and cats,respectively;dry matter basis)are recommended to alleviate aging-associated reductions in the mass and function of skeletal muscles and bones.Pet-food grade animal-sourced foodstuffs are excellent sources of both proteinogenic amino acids and taurine for cats and dogs,and can help to optimize their growth,development,and health.展开更多
In this study,it is aimed to examine the knowledge level of reading stray dogs’behavior and the correct approach.Understanding the aggression of dogs and understanding their behavior is very important for stray dogs ...In this study,it is aimed to examine the knowledge level of reading stray dogs’behavior and the correct approach.Understanding the aggression of dogs and understanding their behavior is very important for stray dogs and dog owners in social life.Questionnaires prepared online were shared with 279 people of different ages and genders working in different fields in 50 provinces located in different regions,and the feedback obtained by answering voluntarily was taken into consideration.As a result of the study,when a dangerous-looking dog is encountered,it is necessary to stay as calm as possible and start to walk away slowly,without losing sight of the dog,with short steps,and without running under any circumstances.But without turning your back,because turning your back on the dog is a sign of weakness and an invitation to attack.While 36%left unanswered the question of what should be done at the time of the dog attack,20.1%replied by saying that they would stand calmly and shout and scare,and 20.9%would shout and stop.The results of the survey show that there are inaccuracies and deficiencies in both the body language of the dogs and the way they approach the dog.The participants answered the frequency of encountering stray animals by saying 75.9%daily.A safe approach to dogs or knowing the suitable approaches to calm a dangerous dog is very important in eliminating the dangers.These results show that there is a need for correct,informative activities on dog behavior and the right approach.展开更多
Background: Separation-related disorders are prevalent in dogs and can result in problem behaviours such as inappropriate elimination, destructive behaviour, and distress vocalizations which occur when an owner is abs...Background: Separation-related disorders are prevalent in dogs and can result in problem behaviours such as inappropriate elimination, destructive behaviour, and distress vocalizations which occur when an owner is absent or perceived as absent. Numerous natural products are marketed for managing anxiety in dogs;however, few, if any, of these products have documented evidence of efficacy in veterinary behaviour. Purpose: This open, multicentric clinical trial aimed to assess the efficacy of a new supplement containing alpha-casozepine and fish muscle hydrolysate on the separation-related problem in dogs and the impact on the quality of life of dogs and their pet owners. Material and Methods: Fifty-one dogs with clinical signs compatible with separation-related problems were included. The dogs were treated with a complementary feed (Zylkene Plus, Vetoquinol, France) for 30 days. Separation-related behaviour assessment (SRP), emotional disorders assessment (EDED) and the quality of life (QoL) of the pets and their pet owner were assessed at baseline and the end of the study by the veterinarians. In addition, owners were asked to rate their dog’s SRP weekly after enrolment using the same questionnaire that the veterinarian used at the beginning of the study. Results: There was a statistically significant improvement in the SRP, EDED, and QoL scores (P Conclusion: The results of this study support the hypothesis that the combination of alpha-casozepine and fish muscle hydrolysate is a promising and effective option to reduce the frequency and severity of separation-related behaviour in dogs and improve the quality of dogs and their owners.展开更多
Ian McEwan’s Black Dogs reflects the anxiety and panic after the Second World War vividly with charming words.Based on Ian McEwan’s Black Dogs,many scholars have explored and acquired great achievements in trauma wr...Ian McEwan’s Black Dogs reflects the anxiety and panic after the Second World War vividly with charming words.Based on Ian McEwan’s Black Dogs,many scholars have explored and acquired great achievements in trauma writing and historical writing.Through analyzing the similarities of the heroine’s long-term neglected inner needs and the cruelly killed creatures in nature,this paper finds there is an intimate connection between female and nature in Black Dogs.However,instead of being in a constant state of repression,female and nature will fight back.To sum up,this paper attempts to make an ecofeminism interpretation of Ian McEwan’s Black Dogs.A conclusion may be reached that June’s spiritual awakening resonates with enhancement of nature’s power.展开更多
Background: Quality of life (QoL) is a term used to evaluate general well-being, and it is defined as ‘the degree to which an individual enjoys his or her life. Within the realm of medicine, the evaluation of QoL fre...Background: Quality of life (QoL) is a term used to evaluate general well-being, and it is defined as ‘the degree to which an individual enjoys his or her life. Within the realm of medicine, the evaluation of QoL frequently involves examining how disease exerts a detrimental impact, diminishing the enjoyment and fulfilment experienced by the individual. Dermatological diseases have been found to exert a substantial negative influence on the QoL of dogs and their owners due to nuisance and stress related to the disease but also due to the caregiver burden. In the management of bacterial skin infections, topical therapy is commonly administered alongside systemic antibiotics. Nonetheless, the protracted duration of treatment and difficulties in ensuring owner compliance can introduce a significant caregiver burden, potentially exacerbating the challenges associated with these conditions. Purpose: This study aimed to evaluate the impact on the quality of life (QoL) of dogs with dermatologic diseases after fluorescent light energy (FLE) treatment. Methods: The study was an open, prospective, multicentric clinical trial that included dogs with various dermatological conditions. The dogs received FLE treatment once weekly until the clinical resolution was achieved. Owners completed a validated questionnaire to assess the QoL of their dogs before and after therapy. Results: Thirty-five dogs with deep pyoderma, interdigital furunculosis, pyotraumatic dermatitis, wounds and perianal fistulas were included. All dogs received two sessions of fluorescent light energy once a week. Median treatment duration was 9 weeks for perianal fistula, 7 weeks for interdigital furunculosis, 5 weeks for deep pyoderma, 3 weeks for wounds and 1.5 weeks for pyotraumatic dermatitis. Complete remission was noted in 86% of dogs, and 14% showed an improvement but partial remission. The majority of owners reported a positive impact on their dogs’ QoL after therapy, and 74% of the dogs showed at least a 50% reduction in QoL scores. Conclusion: Fluorescent light energy has been shown to exert beneficial effects on the healing of dermatological diseases and the quality of life (QoL) in dogs and their owners, whether used as a standalone treatment or in combination with standard care therapies. Additionally, it was well-tolerated by the dogs. This study emphasizes the significance of considering both the owner’s and dog’s QoL when evaluating the therapeutic efficacy of dermatological treatments.展开更多
Jumping sun dogs are rapid light flashes changing over clouds, with some of them located close to the places of halo formation in thunder storms clouds. This paper presents an outline of some aspects that are required...Jumping sun dogs are rapid light flashes changing over clouds, with some of them located close to the places of halo formation in thunder storms clouds. This paper presents an outline of some aspects that are required for understanding the jumping sun dogs, using some experiments with light scattering in complex fluids. In our analogy, we have observed the jumping laser dogs, in which the ice crystals are replaced by needlelike structures of ferrofluid, the electric field in the atmosphere is represented by an external magnetic field, and the laser beam scattered by the ferrofluid structure has the same role of the sun as the source of light scattered by the ice crystals subjected to changing electric fields in thunderstorm clouds.展开更多
The pharmacokinetics and absolute bioavailability of the sublingual naloxone tablet were studied with HPLC-electrochemical detection. Eight male dogs received single 5 mg dose of naloxone intravenously, the plasma con...The pharmacokinetics and absolute bioavailability of the sublingual naloxone tablet were studied with HPLC-electrochemical detection. Eight male dogs received single 5 mg dose of naloxone intravenously, the plasma concentration-time curves could be fitted to two-compartment open model, with 12.0 min of t1/2( , 143.4 min of t1/2( and 7.92 mg(min/L of AUC. The same eight dogs received 5 mg dose of the sublingual naloxone tablet after an interval of a week. The main pharmacokinetic parameters were: t1/2ka = 11.0 min, t1/2( = 15.4 min, t1/2( = 164.1 min, Tmax = 27.7 min, Cmax = 34.2 ng / ml, and AUC = 6.79 mg(min / L, respectively. The plasma concentration-time curves were fitted to the first order absorption two-compartment open model also. The mean absolute bioavailability of the sublingual naloxone tablet was 86.8 ( 10.9%. No statistically significant differences were found with t1/2(, t1/2(, ( and ( between the two routes of administration. These results indicated that the course of disposition for naloxone in dogs was similar for the two routes of administration, and the absolute bioavailability of the sublingual naloxone tablet was high. Thus satisfactory clinical effects could be expected.展开更多
Objective:To evaluate the Anaplasma phagocytophilum(A.phagocytophilum),Ehrlichia canis(E.canis,Dirofilaria immitis(D.immitis)(canine heartworm),Borrelia burgdorferi(B.burgdorferi)infections in countryside dogs from Yu...Objective:To evaluate the Anaplasma phagocytophilum(A.phagocytophilum),Ehrlichia canis(E.canis,Dirofilaria immitis(D.immitis)(canine heartworm),Borrelia burgdorferi(B.burgdorferi)infections in countryside dogs from Yunnan,Hainan and Anhui provinces.Methods:Serum samples were collected from 26 dogs in Yunnan.Hainan and Anhui provinces.The samples were tested using a commercial ELISA rapid diagnostic assay kit(SNAP^(?)4Dx^(?);IDEXX Laboratories,Inc.U.S.A.).Meaiiwliile,indirect immunofluorescence assay(IFA)recommended by WHO was conducted to delect IgG to A.phagocytophilum.Two methods were analyzed and compared.Results:The number of serologically positive dogs for IgG to A.phagocytophilum was only 2which was from Hainan province and none of the 26 dogs responded positive for E.canu.D.immitis(canine heartworm,and B.burgdorferi by ELISA rapid diagnostic method.The number of serologically positive dogs for IgG to A.phagocytophilum was 13(50%)by IFA method.Data of the two methods were analyzed by statistical software and the difference was statistically significant(P=0.002).Conclusions:It can be concluded that IFA method was more sensitive than ELISA rapid diagnostic method.However,we need conduct further and intensive epidemiology survey on tick-born diseases pathogens including.4.phagocytophilum,E.canis,D.immitis(canine heartworm),and B.burgdorferi which have public health significance.展开更多
Objective:To evaluate clinical and hematological aspects of dogs naturally infected with Hepatozoon canis(H.canis)presented at the Small Animal Clinics of Guru Angad Dev Veterinary and Animal Sciences University,Ludhi...Objective:To evaluate clinical and hematological aspects of dogs naturally infected with Hepatozoon canis(H.canis)presented at the Small Animal Clinics of Guru Angad Dev Veterinary and Animal Sciences University,Ludhiana.Methods:Blood films of 34 naturally infected dogs were examined for haematological alterations and parasitaemia.Signalment and clinical signs were recorded from the animals.Clinical histories were filled oul during the consultation.Results:Of the 34 positive dogs by Giemsa stained peripheral blood films.88.23%presented parasilaemia by H.canis only,while 11.77%had the combination of H.canis,Babesia sp.and Ehrlichia sp.Young male dogs less than oue-year-old,of nondescript breed,were the most commonly affected.And 26.47%were presented with anorexia/inappetence as the only clinical symptom.Other clinical symptoms were mild to moderate fever,pale mucosae and lethargy;a few were also showing the signs of vomiting and diarrhoea.Haematological alterations showed mainly normochromic-normocytic anaemia,leukocytosis and neutrophilia.Conclusions:The findings of this study substantiate that H.canis caused clinical and haematological alterations of the varied intensity in dogs,even with low parasilaemia.should he taken into consideration.展开更多
OBJECTIVE To compare the pharmacokinetics and pharmacodynamics of PEG30-rhG-CSF administered to beagle dogs at three different dosages with PEG20-rhG-CSF administered at one dosage, and to provide an experimental basi...OBJECTIVE To compare the pharmacokinetics and pharmacodynamics of PEG30-rhG-CSF administered to beagle dogs at three different dosages with PEG20-rhG-CSF administered at one dosage, and to provide an experimental basis for clinical trials.METHODS Beagle dogs received single, subcutaneous doses of PEG30-rhG-CSF at 100, 200 and 400 μg/kg or PEG20-rhG-CSF at 200 μg/kg. PEG30-rhG-CSF and PEG20-rhG-CSF concentrations in serum were analyzed using an enzymeqinked immunosorbent assay (ELISA). WBC, ANC and PLT counts of whole blood samples were measured using fully automated analytic instrumentation. Pharmacokinetic and pharmacodynamic parameters were calculated using DAS 2.0 statistical analysis software.METHODS Beagle dogs received single, subcutaneous doses of PEG30-rhG-CSF at 100, 200 and 400 μg/kg or PEG20-rhG-CSF at 200μg/kg. PEG30-rhG-CSF and PEG20-rhG-CSF concentrations in serum were analyzed using an enzyme-linked immunosorbent assay (ELISA). WBC, ANC and PLT counts of whole blood samples were measured using fully automated analytic instrumentation. Pharmacokinetic and pharmacodynamic parameters were calculated using DAS 2.0 statistical analysis software. RESULTS The pharmacokinetic parameters of PEG30-rhG-CSF calculated from the serum concentration data determined by ELISA were as follows: the mean elimination half-life (t1/2ke) was 40.6 h (33.5-45.4 h); the mean time to reach peak concentration (Tmax) was 19.2 h (11.7-24.0 h); the drug clearance from the serum (CL) was decreased with increasing doses; the peak concentration (Cmax) and the area under the serum concentration-time curve (AUC) were increased with increasing doses. For PEG20-rhG- CSF, the half-life was shorter (12 h) and Tmax was achieved much earlier (10 h) relative to PEG30-rhG-CSF. The AUC of PEG30- rhG-CSF was much greater than that of PEG20-rhG-CSF, and the relative bioavailability with a subcutaneous injection was 158.7%. Administration of single doses of PEG30-rhG-CSF resulted in substantial increases in the absolute The time to reach ANC (ANCTmax) neutrophil count (ANC). was 72 h. The maximum observed absolute neutrophil counts (ANCmax) and the area over the baseline effect curve (AOBEC) was increased with increasing doses. The effect-elimination half-life (t1/2E) ranged from 60 h to 80 h after subcutaneous administration. The PLT count was slightly elevated 8-12 h after s.c. injection, and declined after 24 h. CONCLUSION The mean elimination half-life of PEG30-rhG- CSF was longer than that of PEG20-rhG-CSF at the same dose, and the other main pharmacokinetic and pharmacodynamic parameters of PEG30-rhG-CSF, including C ANCmax, AUC and AOBEC were much greater than those following PEG20-rhG-CSF injection.展开更多
Background: During sperm maturation, there is a reorganization of fatty acids from plasmatic membrane of the spermatozoa, which allows higher membrane integrity and acquisition of sperm motility. However, the fatty a...Background: During sperm maturation, there is a reorganization of fatty acids from plasmatic membrane of the spermatozoa, which allows higher membrane integrity and acquisition of sperm motility. However, the fatty acid profile during sperm maturation remains unclear in dogs. Thus, the aim of this study was to identify the fatty acids from the epididymal spermatozoa and plasma during the sperm maturation, and observed changes in the motility and plasmatic membrane parameters. Twenty one adult dogs were used, subsequently to bilateral orchiectomy and epididymal storage, sperm samples were collected from the different segments of the epididymis. Samples were evaluated for conventional microscopy, computer-assisted motility analysis, sperm plasma membrane permeability and the fatty acid analysis(lipids were extracted, transmethylated and analyzed by chromatography).Results: Caput and corpus sperm showed lower values for the motility variables evaluated and plasmatic membrane integrity, indicating different levels of the fatty acids organization. Saturated, monounsaturated and polyunsaturated fatty acids were in higher concentrations in the spermatozoa from epididymis cauda. Highlighting the presence of caprylic, stearic and docosahexaenoic acids.Conclusions: These findings demonstrate the influence of the fatty acid profile during sperm maturation, assigning physical and chemical changes in sperm cells, essential for fertilization.展开更多
Didanosine is an effective antiviral drug in untreated and antiretroviral therapy-experienced patients with Human Immunodeficiency Virus (HIV). An automated system using on-line solid extraction and High Performance L...Didanosine is an effective antiviral drug in untreated and antiretroviral therapy-experienced patients with Human Immunodeficiency Virus (HIV). An automated system using on-line solid extraction and High Performance Liquid Chromatography (HPLC) with ultraviolet (UV) detection was developed and validated for pharmacokinetic analysis of didanosine in dog plasma. Modifications were introduced on a previous methodology for simultaneous analysis of antiretroviral drugs in human plasma. Extraction was carried out on C18 cartridges, with high extraction yield as stationary phase, whereas mobile phase consisted of a mixture of 0.02 M potassium phosphate buffer, acetonitrile (KH2PO4: acetonitrile: 96:4, v/v) and 0.5% (w/v) of heptane sulphonic acid. The pH was adjusted to 6.5 with triethylamine. All samples and standard solutions were chromatographed at 28 1C. For an isocratic run, the fiux was 1.0 mL/min, detection was at 250 nm and injected volume was 20 mL. The method was selective and linear for concentrations between 50 and 5000 ng/mL. Drug stability data ranged from 96% to 98%, and limit of quantification was 25 ng/mL. Extraction yield was up to 95%. Drug stability in dog plasma was kept frozen at 20 1C for one month after three freeze–thaw cycles, and for 24 h after processing in the auto sampler. Assay was successfully applied to measure didanosine concentrations in plasma dogs.展开更多
The goal of this study was to evaluate the influence of natural variation in the regenerative status of dog tissues on the signs of hormesis, which are evident after total body exposure to low daily doses of external ...The goal of this study was to evaluate the influence of natural variation in the regenerative status of dog tissues on the signs of hormesis, which are evident after total body exposure to low daily doses of external gamma radiation throughout the lifespan. Ninety beagle dogs of both sexes were irradiated with cobalt 60 at 0.003 Gy/day commencing 1 year after birth to death. Control (n = 169) and irradiated animals underwent whole-life clinical observation and autopsy, and were then retrospectively divided into two subgroups with (W) or without benign tumors or tumors of unknown nature (WO) that were clinically recorded on single days throughout the lifespan. Radiation hormesis was only detected in subgroup WO, which had life span (LS) of 10.7 years in the absence of radiation. The radiogenic prolongation of life to 11.8 years in the WO subgroup (p 【0.05) was similar to that in the W control and irradiated W subgroups (11.8 and 11.5 years, respectively). The number of solid malignancies found upon autopsy of the control WO subgroup was less (39.5%) than that evident in the control W subgroup (60%). Compared to the irradiated W subgroup, irradiation of the WO subgroup was accompanied by a slight increase (1.14-fold) in the number of solid malignancies evident at autopsy and in the clinical signs of tissue atrophy and body weight loss (2.4-fold and 2.4-fold, respectively), but was accompanied by strong reductions in the extent of anemia and hemoblastoses (】10-fold for both). The data exclude the notion that radiation is associated with healing, but suggest that certain pathologies (e.g., hemoblastoses) may be substituted with other less dangerous somatic diseases in weaker animals only.展开更多
基金Kunshan Municipal Government research funding(Grant Number:22KKSGR075).
文摘Canine parvovirus 2(CPV-2)is a highly contagious virus in dogs that typically causes hemorrhagic enteritis and a high mortality rate in unvaccinated puppies.The genetic variability and antigenic diversity of CPV-2 hinder its efective prevention of infection by vaccination.To investigate the epidemiology and genetic characteristics of CPV-2 in China,rectal swabs from afected dogs were collected from diferent animal clinics in Kunshan from 2022 to 2023.Preliminary detection and capsid gene sequencing of CPV-2 were performed using previously described primers and protocols.The overall detection rate for CPV-2 was 16.5%(33/200).A signifcant association was found between the CPV-2-positivity and clinical signs,age,breed and vaccination status.Sequence analysis revealed the presence of CPV-2c genotypes in all positive samples,which were genetically similar to other Asian CPV-2c strains.Notably,four key mutations(A5G,F267Y,Y324I and Q370R)were detected in all isolates,and one novel mutation(I447M)was detected in three CPV-2 isolates.These mutations in the CPV-2 strains could impact vaccine efcacy and the efectiveness of the virus immune evasion.Surprisingly,no recombination events were observed between the identifed CPV-2c strains and reference strains from China.Our data revealed that amino acid residues 324,426 and 440 of VP2 may under strong selection pressure.This pattern of genetic variation in the CPV-2 lineage warrants continuous laboratory-based surveillance programs in other parts of China to better understand the pattern of seasonal distribution and association between emerging genotypes and the intensity of disease severity.
基金the Experimental Animal Research Project of Hubei Province(Grant No.2023CFA005).
文摘Feline panleukopenia virus(FPV)is a single-stranded DNA virus that can infect cats and cause feline panleukopenia,which is a highly contagious and fatal disease in felines.The sequence of FPV is highly variable,and mutations in the amino acids of its capsid protein play crucial roles in altering viral virulence,immunogenicity,host selection,and other abilities.In this study,the epidemiology of FPV was studied using 746 gastrointestinal swab samples derived from cats that presented gastrointestinal symptoms specifcally,diarrhea or vomiting during the period spanning from 2018 to 2022.The overall prevalence of FPV-positive patients among these samples was determined to be 45.4%.Capsid(virion)protein 2(VP2)gene of each FPV-positive sample was sequenced and amplifed,yielding 65 VP2 sequences.Among them,six VP2 gene sequences were detected in the majority of the samples test positive for FPV,and these positive samples originated from a diverse range of geographical locations.These isolates were named FPV-6,FPV-10,FPV-15,FPV-251,FPV-271 and FPV-S2.Additionally,the substitution of Ala300Pro(A300P)in VP2 was detected for the frst time in feline-derived FPV(FPV-251).FPV-251 isolate,with this substitution in VP2 protein,exhibited stable proliferative capacity in Madin-Darby canine kidney(MDCK)cells and A72 cells.FPV-271 was selected as the FPV control isolate due to its single amino acid diference from VP2 protein of FPV-251 at position 300(FPV-271 has alanine,while FPV-251 has proline).After oral infection,both FPV-251 and FPV-271 isolates caused feline panleukopenia,which is characterized by clinical signs of enterocolitis.However,FPV-251 can infect dogs through the oral route and cause gastrointestinal(GI)symptoms with lesions in the intestine and mesenteric lymph nodes(MLNs)of infected dogs.This is the frst report on the presence of an A300P substitution in VP2 protein of feline-derived FPV.Additionally,FPV isolate with a substitution of A300P at VP2 protein demonstrated efcient replication capabilities in canine cell lines and the ability to infect dogs.
基金Fapesp 2014/22827–7Ministério da Saúde do BrasilFundação Faculdade de Medicina and CNPq Grant to JC:301275/2019–0.
文摘Retroviruses have been proven to cause infections and diseases in a series of mammalian hosts but not in dogs.Then,this letter discussed the dog susceptibility to retrovirus infection,encompassing arguments to understand why dogs may have not been infected by retroviruses thus far.The potential resistance of retrovirus in dogs enables this provocative short communication to discuss this question,looking at some evolutive aspects.The lineage of canids has shown,throughout its evolutionary history,a smaller accumulation of retroviruses in canid genomes,classifed as endogenous retroviruses.In this context,the genomes of canids seem to ofer obstacles,which have been evolutionarily conserved,in the face of retroviral infection.
文摘The aim of the present study was to compare the ixodicide efficacy of 1% permethrin applied as a shampoo-bath in single treatment and a combined formulation of 2% permethrin + 1% piperonyl butoxide applied as powder in a single treatment against Rhipicephalus sanguineus ticks, in naturally infested dogs. Eighteen adult cross-mixed dogs, harboring to at least 20 ticks/animal, were selected on pre-treatment live tick counts. On day 0, the dogs were then divided in 3 groups of 6 animals each, for treatment: Group 1 (G1) received 1% permethrin applied as shampoo-bath (approximately 10 ml/kg bw), according to label instructions. G2 was treated with 2% permethrin + 1% piperonyl butoxide applied as powder, and rubbed as massage on the body, as recommended by the producer. G3 served as a non-treated control. After the treatment, the dogs were checked out for live ticks counting on days 0, 1, 7, and 14. The ixodicide efficacy was assessed based on the percentage reductions of ticks on the days analyzed post-treatment, with respect to the untreated control. Results showed that permethrin alone removed ticks on 81%, 93.1% and 89.6% for days 1, 7 and 14, respectively. The combined formulation of 2% permethrin + 1% piperonyl butoxide exerted a better efficacy of 98.8, 97.7 and 97.0%, respectively. It is concluded that this combined formulation was highly effective at rapidly repelling and killing Riphicephalus sanguineus ticks on naturally infected dogs, showing a significant effect on days 1, 7 and 14 after tick exposure. The sustained high and quick level of efficacy of this combination may well interfere with the transmission of Riphicephalus sanguineus ticks. It is concluded that the sustained high level of efficacy of the permethrin + piperonyl butoxide combination may well exert an additive effect and could interfere with the transmission of Riphicephalus sanguineus ticks.
文摘Activity 1.Think about the following questions and write down your answers before reading the text.1.Do you know some foods are toxic to dogs?2.What foods do you avoid giving your dog?
文摘Chronic kidney disease is commonly diagnosed in dogs,and clinical signs may be aggravated when infected agents are involved.In this case report,33 dogs with chronic kidney disease were clinically evaluated and serologically tested for Leptospira spp.,Ehrlichia canis,and Anaplasma phagocytophilum.The seroprevalence for Leptospira spp.was 39.4%.The most frequent serovars found were Pyrogenes,Canicola,Bratislava and Australis,with serological titers between 1:100 to 1:800.Clinical signs included fever,depression,decreased body condition,vomiting and hema‑turia.Signifcant laboratory fndings were anemia,leukocytosis,thrombocytopenia,increased liver enzymes,urea and creatinine,hyperbilirubinemia and hyperphosphatemia.All leptospira seronegative dogs were positive for one or both monitored homoparasites(i.e.,E.canis and A.phagocytophilum);only three leptospira seropositive dogs were positive for one or both hemoparasites.Findings also suggest that endemic hemoparasites of dogs should be moni‑tored in dogs with a kidney condition for a better clinical picture of the patients and therapeutic approach.
基金This work was supported by Texas A&M AgriLife Research(H-8200).
文摘Domestic cats and dogs are carnivores that have evolved differentially in the nutrition and metabolism of amino acids.This article highlights both proteinogenic and nonproteinogenic amino acids.Dogs inadequately synthesize citrulline(the precursor of arginine)from glutamine,glutamate,and proline in the small intestine.Although most breeds of dogs have potential for adequately converting cysteine into taurine in the liver,a small proportion(1.3%-2.5%)of the Newfoundland dogs fed commercially available balanced diets exhibit a deficiency of taurine possibly due to gene mutations.Certain breeds of dogs(e.g.,golden retrievers)are more prone to taurine deficiency possibly due to lower hepatic activities of cysteine dioxygenase and cysteine sulfinate decarboxylase.De novo synthesis of arginine and taurine is very limited in cats.Thus,concentrations of both taurine and arginine in feline milk are the greatest among domestic mammals.Compared with dogs,cats have greater endogenous nitrogen losses and higher dietary requirements for many amino acids(e.g.,arginine,taurine,cysteine,and tyrosine),and are less sensitive to amino acid imbalances and antagonisms.Throughout adulthood,cats and dogs may lose 34%and 21%of their lean body mass,respectively.Adequate intakes of high-quality protein(i.e.,32%and 40%animal protein in diets of aging dogs and cats,respectively;dry matter basis)are recommended to alleviate aging-associated reductions in the mass and function of skeletal muscles and bones.Pet-food grade animal-sourced foodstuffs are excellent sources of both proteinogenic amino acids and taurine for cats and dogs,and can help to optimize their growth,development,and health.
文摘In this study,it is aimed to examine the knowledge level of reading stray dogs’behavior and the correct approach.Understanding the aggression of dogs and understanding their behavior is very important for stray dogs and dog owners in social life.Questionnaires prepared online were shared with 279 people of different ages and genders working in different fields in 50 provinces located in different regions,and the feedback obtained by answering voluntarily was taken into consideration.As a result of the study,when a dangerous-looking dog is encountered,it is necessary to stay as calm as possible and start to walk away slowly,without losing sight of the dog,with short steps,and without running under any circumstances.But without turning your back,because turning your back on the dog is a sign of weakness and an invitation to attack.While 36%left unanswered the question of what should be done at the time of the dog attack,20.1%replied by saying that they would stand calmly and shout and scare,and 20.9%would shout and stop.The results of the survey show that there are inaccuracies and deficiencies in both the body language of the dogs and the way they approach the dog.The participants answered the frequency of encountering stray animals by saying 75.9%daily.A safe approach to dogs or knowing the suitable approaches to calm a dangerous dog is very important in eliminating the dangers.These results show that there is a need for correct,informative activities on dog behavior and the right approach.
文摘Background: Separation-related disorders are prevalent in dogs and can result in problem behaviours such as inappropriate elimination, destructive behaviour, and distress vocalizations which occur when an owner is absent or perceived as absent. Numerous natural products are marketed for managing anxiety in dogs;however, few, if any, of these products have documented evidence of efficacy in veterinary behaviour. Purpose: This open, multicentric clinical trial aimed to assess the efficacy of a new supplement containing alpha-casozepine and fish muscle hydrolysate on the separation-related problem in dogs and the impact on the quality of life of dogs and their pet owners. Material and Methods: Fifty-one dogs with clinical signs compatible with separation-related problems were included. The dogs were treated with a complementary feed (Zylkene Plus, Vetoquinol, France) for 30 days. Separation-related behaviour assessment (SRP), emotional disorders assessment (EDED) and the quality of life (QoL) of the pets and their pet owner were assessed at baseline and the end of the study by the veterinarians. In addition, owners were asked to rate their dog’s SRP weekly after enrolment using the same questionnaire that the veterinarian used at the beginning of the study. Results: There was a statistically significant improvement in the SRP, EDED, and QoL scores (P Conclusion: The results of this study support the hypothesis that the combination of alpha-casozepine and fish muscle hydrolysate is a promising and effective option to reduce the frequency and severity of separation-related behaviour in dogs and improve the quality of dogs and their owners.
文摘Ian McEwan’s Black Dogs reflects the anxiety and panic after the Second World War vividly with charming words.Based on Ian McEwan’s Black Dogs,many scholars have explored and acquired great achievements in trauma writing and historical writing.Through analyzing the similarities of the heroine’s long-term neglected inner needs and the cruelly killed creatures in nature,this paper finds there is an intimate connection between female and nature in Black Dogs.However,instead of being in a constant state of repression,female and nature will fight back.To sum up,this paper attempts to make an ecofeminism interpretation of Ian McEwan’s Black Dogs.A conclusion may be reached that June’s spiritual awakening resonates with enhancement of nature’s power.
文摘Background: Quality of life (QoL) is a term used to evaluate general well-being, and it is defined as ‘the degree to which an individual enjoys his or her life. Within the realm of medicine, the evaluation of QoL frequently involves examining how disease exerts a detrimental impact, diminishing the enjoyment and fulfilment experienced by the individual. Dermatological diseases have been found to exert a substantial negative influence on the QoL of dogs and their owners due to nuisance and stress related to the disease but also due to the caregiver burden. In the management of bacterial skin infections, topical therapy is commonly administered alongside systemic antibiotics. Nonetheless, the protracted duration of treatment and difficulties in ensuring owner compliance can introduce a significant caregiver burden, potentially exacerbating the challenges associated with these conditions. Purpose: This study aimed to evaluate the impact on the quality of life (QoL) of dogs with dermatologic diseases after fluorescent light energy (FLE) treatment. Methods: The study was an open, prospective, multicentric clinical trial that included dogs with various dermatological conditions. The dogs received FLE treatment once weekly until the clinical resolution was achieved. Owners completed a validated questionnaire to assess the QoL of their dogs before and after therapy. Results: Thirty-five dogs with deep pyoderma, interdigital furunculosis, pyotraumatic dermatitis, wounds and perianal fistulas were included. All dogs received two sessions of fluorescent light energy once a week. Median treatment duration was 9 weeks for perianal fistula, 7 weeks for interdigital furunculosis, 5 weeks for deep pyoderma, 3 weeks for wounds and 1.5 weeks for pyotraumatic dermatitis. Complete remission was noted in 86% of dogs, and 14% showed an improvement but partial remission. The majority of owners reported a positive impact on their dogs’ QoL after therapy, and 74% of the dogs showed at least a 50% reduction in QoL scores. Conclusion: Fluorescent light energy has been shown to exert beneficial effects on the healing of dermatological diseases and the quality of life (QoL) in dogs and their owners, whether used as a standalone treatment or in combination with standard care therapies. Additionally, it was well-tolerated by the dogs. This study emphasizes the significance of considering both the owner’s and dog’s QoL when evaluating the therapeutic efficacy of dermatological treatments.
文摘Jumping sun dogs are rapid light flashes changing over clouds, with some of them located close to the places of halo formation in thunder storms clouds. This paper presents an outline of some aspects that are required for understanding the jumping sun dogs, using some experiments with light scattering in complex fluids. In our analogy, we have observed the jumping laser dogs, in which the ice crystals are replaced by needlelike structures of ferrofluid, the electric field in the atmosphere is represented by an external magnetic field, and the laser beam scattered by the ferrofluid structure has the same role of the sun as the source of light scattered by the ice crystals subjected to changing electric fields in thunderstorm clouds.
文摘The pharmacokinetics and absolute bioavailability of the sublingual naloxone tablet were studied with HPLC-electrochemical detection. Eight male dogs received single 5 mg dose of naloxone intravenously, the plasma concentration-time curves could be fitted to two-compartment open model, with 12.0 min of t1/2( , 143.4 min of t1/2( and 7.92 mg(min/L of AUC. The same eight dogs received 5 mg dose of the sublingual naloxone tablet after an interval of a week. The main pharmacokinetic parameters were: t1/2ka = 11.0 min, t1/2( = 15.4 min, t1/2( = 164.1 min, Tmax = 27.7 min, Cmax = 34.2 ng / ml, and AUC = 6.79 mg(min / L, respectively. The plasma concentration-time curves were fitted to the first order absorption two-compartment open model also. The mean absolute bioavailability of the sublingual naloxone tablet was 86.8 ( 10.9%. No statistically significant differences were found with t1/2(, t1/2(, ( and ( between the two routes of administration. These results indicated that the course of disposition for naloxone in dogs was similar for the two routes of administration, and the absolute bioavailability of the sublingual naloxone tablet was high. Thus satisfactory clinical effects could be expected.
基金supported by the National Basic Research Program of China(973 Program)2010CB530200(2010CB530206)the China-US Collaborative Program on Emerging and Re-emerging Infectious Disease(No.1U2GGH000018-01)
文摘Objective:To evaluate the Anaplasma phagocytophilum(A.phagocytophilum),Ehrlichia canis(E.canis,Dirofilaria immitis(D.immitis)(canine heartworm),Borrelia burgdorferi(B.burgdorferi)infections in countryside dogs from Yunnan,Hainan and Anhui provinces.Methods:Serum samples were collected from 26 dogs in Yunnan.Hainan and Anhui provinces.The samples were tested using a commercial ELISA rapid diagnostic assay kit(SNAP^(?)4Dx^(?);IDEXX Laboratories,Inc.U.S.A.).Meaiiwliile,indirect immunofluorescence assay(IFA)recommended by WHO was conducted to delect IgG to A.phagocytophilum.Two methods were analyzed and compared.Results:The number of serologically positive dogs for IgG to A.phagocytophilum was only 2which was from Hainan province and none of the 26 dogs responded positive for E.canu.D.immitis(canine heartworm,and B.burgdorferi by ELISA rapid diagnostic method.The number of serologically positive dogs for IgG to A.phagocytophilum was 13(50%)by IFA method.Data of the two methods were analyzed by statistical software and the difference was statistically significant(P=0.002).Conclusions:It can be concluded that IFA method was more sensitive than ELISA rapid diagnostic method.However,we need conduct further and intensive epidemiology survey on tick-born diseases pathogens including.4.phagocytophilum,E.canis,D.immitis(canine heartworm),and B.burgdorferi which have public health significance.
基金Supported by Directorate of Research,Guru Angad Dev Veterinary and Animal Sciences University,Ludhiana-141004,India.Grant No.-RKVYB-2(Ⅲ)c(d)DR-2,sanctioned on October,2010
文摘Objective:To evaluate clinical and hematological aspects of dogs naturally infected with Hepatozoon canis(H.canis)presented at the Small Animal Clinics of Guru Angad Dev Veterinary and Animal Sciences University,Ludhiana.Methods:Blood films of 34 naturally infected dogs were examined for haematological alterations and parasitaemia.Signalment and clinical signs were recorded from the animals.Clinical histories were filled oul during the consultation.Results:Of the 34 positive dogs by Giemsa stained peripheral blood films.88.23%presented parasilaemia by H.canis only,while 11.77%had the combination of H.canis,Babesia sp.and Ehrlichia sp.Young male dogs less than oue-year-old,of nondescript breed,were the most commonly affected.And 26.47%were presented with anorexia/inappetence as the only clinical symptom.Other clinical symptoms were mild to moderate fever,pale mucosae and lethargy;a few were also showing the signs of vomiting and diarrhoea.Haematological alterations showed mainly normochromic-normocytic anaemia,leukocytosis and neutrophilia.Conclusions:The findings of this study substantiate that H.canis caused clinical and haematological alterations of the varied intensity in dogs,even with low parasilaemia.should he taken into consideration.
基金National High Technology Research and Development Program of China(No.2007BAI14IB04)Major State Basic Research Development Program(No.2004CB518902)
文摘OBJECTIVE To compare the pharmacokinetics and pharmacodynamics of PEG30-rhG-CSF administered to beagle dogs at three different dosages with PEG20-rhG-CSF administered at one dosage, and to provide an experimental basis for clinical trials.METHODS Beagle dogs received single, subcutaneous doses of PEG30-rhG-CSF at 100, 200 and 400 μg/kg or PEG20-rhG-CSF at 200 μg/kg. PEG30-rhG-CSF and PEG20-rhG-CSF concentrations in serum were analyzed using an enzymeqinked immunosorbent assay (ELISA). WBC, ANC and PLT counts of whole blood samples were measured using fully automated analytic instrumentation. Pharmacokinetic and pharmacodynamic parameters were calculated using DAS 2.0 statistical analysis software.METHODS Beagle dogs received single, subcutaneous doses of PEG30-rhG-CSF at 100, 200 and 400 μg/kg or PEG20-rhG-CSF at 200μg/kg. PEG30-rhG-CSF and PEG20-rhG-CSF concentrations in serum were analyzed using an enzyme-linked immunosorbent assay (ELISA). WBC, ANC and PLT counts of whole blood samples were measured using fully automated analytic instrumentation. Pharmacokinetic and pharmacodynamic parameters were calculated using DAS 2.0 statistical analysis software. RESULTS The pharmacokinetic parameters of PEG30-rhG-CSF calculated from the serum concentration data determined by ELISA were as follows: the mean elimination half-life (t1/2ke) was 40.6 h (33.5-45.4 h); the mean time to reach peak concentration (Tmax) was 19.2 h (11.7-24.0 h); the drug clearance from the serum (CL) was decreased with increasing doses; the peak concentration (Cmax) and the area under the serum concentration-time curve (AUC) were increased with increasing doses. For PEG20-rhG- CSF, the half-life was shorter (12 h) and Tmax was achieved much earlier (10 h) relative to PEG30-rhG-CSF. The AUC of PEG30- rhG-CSF was much greater than that of PEG20-rhG-CSF, and the relative bioavailability with a subcutaneous injection was 158.7%. Administration of single doses of PEG30-rhG-CSF resulted in substantial increases in the absolute The time to reach ANC (ANCTmax) neutrophil count (ANC). was 72 h. The maximum observed absolute neutrophil counts (ANCmax) and the area over the baseline effect curve (AOBEC) was increased with increasing doses. The effect-elimination half-life (t1/2E) ranged from 60 h to 80 h after subcutaneous administration. The PLT count was slightly elevated 8-12 h after s.c. injection, and declined after 24 h. CONCLUSION The mean elimination half-life of PEG30-rhG- CSF was longer than that of PEG20-rhG-CSF at the same dose, and the other main pharmacokinetic and pharmacodynamic parameters of PEG30-rhG-CSF, including C ANCmax, AUC and AOBEC were much greater than those following PEG20-rhG-CSF injection.
文摘Background: During sperm maturation, there is a reorganization of fatty acids from plasmatic membrane of the spermatozoa, which allows higher membrane integrity and acquisition of sperm motility. However, the fatty acid profile during sperm maturation remains unclear in dogs. Thus, the aim of this study was to identify the fatty acids from the epididymal spermatozoa and plasma during the sperm maturation, and observed changes in the motility and plasmatic membrane parameters. Twenty one adult dogs were used, subsequently to bilateral orchiectomy and epididymal storage, sperm samples were collected from the different segments of the epididymis. Samples were evaluated for conventional microscopy, computer-assisted motility analysis, sperm plasma membrane permeability and the fatty acid analysis(lipids were extracted, transmethylated and analyzed by chromatography).Results: Caput and corpus sperm showed lower values for the motility variables evaluated and plasmatic membrane integrity, indicating different levels of the fatty acids organization. Saturated, monounsaturated and polyunsaturated fatty acids were in higher concentrations in the spermatozoa from epididymis cauda. Highlighting the presence of caprylic, stearic and docosahexaenoic acids.Conclusions: These findings demonstrate the influence of the fatty acid profile during sperm maturation, assigning physical and chemical changes in sperm cells, essential for fertilization.
基金supported by the Research Foundation of the State of So Paulo (FAPESP/Brazil)National Council of Technological and Scientific Development (CNPq/Brazil)
文摘Didanosine is an effective antiviral drug in untreated and antiretroviral therapy-experienced patients with Human Immunodeficiency Virus (HIV). An automated system using on-line solid extraction and High Performance Liquid Chromatography (HPLC) with ultraviolet (UV) detection was developed and validated for pharmacokinetic analysis of didanosine in dog plasma. Modifications were introduced on a previous methodology for simultaneous analysis of antiretroviral drugs in human plasma. Extraction was carried out on C18 cartridges, with high extraction yield as stationary phase, whereas mobile phase consisted of a mixture of 0.02 M potassium phosphate buffer, acetonitrile (KH2PO4: acetonitrile: 96:4, v/v) and 0.5% (w/v) of heptane sulphonic acid. The pH was adjusted to 6.5 with triethylamine. All samples and standard solutions were chromatographed at 28 1C. For an isocratic run, the fiux was 1.0 mL/min, detection was at 250 nm and injected volume was 20 mL. The method was selective and linear for concentrations between 50 and 5000 ng/mL. Drug stability data ranged from 96% to 98%, and limit of quantification was 25 ng/mL. Extraction yield was up to 95%. Drug stability in dog plasma was kept frozen at 20 1C for one month after three freeze–thaw cycles, and for 24 h after processing in the auto sampler. Assay was successfully applied to measure didanosine concentrations in plasma dogs.
文摘The goal of this study was to evaluate the influence of natural variation in the regenerative status of dog tissues on the signs of hormesis, which are evident after total body exposure to low daily doses of external gamma radiation throughout the lifespan. Ninety beagle dogs of both sexes were irradiated with cobalt 60 at 0.003 Gy/day commencing 1 year after birth to death. Control (n = 169) and irradiated animals underwent whole-life clinical observation and autopsy, and were then retrospectively divided into two subgroups with (W) or without benign tumors or tumors of unknown nature (WO) that were clinically recorded on single days throughout the lifespan. Radiation hormesis was only detected in subgroup WO, which had life span (LS) of 10.7 years in the absence of radiation. The radiogenic prolongation of life to 11.8 years in the WO subgroup (p 【0.05) was similar to that in the W control and irradiated W subgroups (11.8 and 11.5 years, respectively). The number of solid malignancies found upon autopsy of the control WO subgroup was less (39.5%) than that evident in the control W subgroup (60%). Compared to the irradiated W subgroup, irradiation of the WO subgroup was accompanied by a slight increase (1.14-fold) in the number of solid malignancies evident at autopsy and in the clinical signs of tissue atrophy and body weight loss (2.4-fold and 2.4-fold, respectively), but was accompanied by strong reductions in the extent of anemia and hemoblastoses (】10-fold for both). The data exclude the notion that radiation is associated with healing, but suggest that certain pathologies (e.g., hemoblastoses) may be substituted with other less dangerous somatic diseases in weaker animals only.