In Mexico the predominant sheep production system is the semi-extensive with grazing during the day and stanchion afternoon and night. Sheep herd are usually small, approximately 10 to 75 heads. The objectives of thes...In Mexico the predominant sheep production system is the semi-extensive with grazing during the day and stanchion afternoon and night. Sheep herd are usually small, approximately 10 to 75 heads. The objectives of these systems are savings and marketing of lambs. Meat is the main economic product of this kind, the breeding is long, which do not control the delivery dates and ages of the sheep are not uniform, affecting the demand for the local market （for the months of June and December）. Therefore the aim of this work was implement a technology that allows the grouping of the estrus and therefore group deliveries for batches of uniform lambs. This technology was designed to suppress the estrus and heifers growth promoter of feedlots, this technology is melengestrol acetate （MGA） which is a synthetic progesterone oral administration that it is easy to manage in the food or alone, economic that it does not represent any risk for sheep females of abortive type, evaluating the effect of the MGA on rate of estrus and gestation in sheep. Work developed in the municipality of Charo from Michoac^in State, M6xico, 20 hair sheep divided in two groups of 10 female, group one treated with MGA and group tow was the whitens. 100% of the sheep treated with a dose of 0.45 mg MGA/head/day for 17 days orally, presented estrus grouped in 5-10 days; however only 50% of the sheep of the witness group presented estrus. In the experimental group there was a rate of 70% with a gestation difference time of no more than ten days gestation and witness group 50%. The MGA is an efficient alternative for the producer of sheep when administered 0.45 mg MGA/head/day for 17 days because inhibits the estrus and once withdrawn treatment manifests estrus synch with which get a rate of gestation elevated by natural riding.展开更多
Animal nutrition is one of the most important limiting factors in animal production, especially in ruminants, providing proteins being the main constraint, due to the limited availability and high cost of protein sour...Animal nutrition is one of the most important limiting factors in animal production, especially in ruminants, providing proteins being the main constraint, due to the limited availability and high cost of protein sources （oilseed meals）. Currently in the dam ＂El lnfiernillo＂ in Michoacan Mexico, has a large population of devil fish （Pterygoplichthys spp.）, which is an economic and ecological problem, because it is not consumed by humans and causes pollution to be discarded directly into the environment. For that reason the objective of this study was to evaluate the use of silage acid devil fish （SADF） in fattening beef cattle as a protein supplement. SADF is defined as a product semi-liquid or pasty mixed with formic acid, which leads to a decrease in pH to near 4.0. Used 18 young bulls （Bos taurus × Bos indicus） for 60 days with a starting weight of 278.9 ± 51.2 kg, housed in individual pens with food and water ad libitum were randomly assigned to three treatments with different levels of inclusion SADF （0%, 12% and 18%）. They were weighed to the beginning of the experiment and later every 30 days, previous fasting of 24 hours. To determine the food consumption, weigh every day the offered food and the surplus. There were no significant differences （P 〈 0.05） among treatments with different levels of inclusion of SADF with respect to daily weight gain, with values of 952 ± 324, 927 ±322 and 854 ± 307 g/day, respectively. The dry matter intake （DMI） was 8.9, 9.3 and 7.7 kg/day to 0%, 12% and 18% of SADF, respectively. In the same values for feed conversion were 9.34, 10.03 and 9.01 kg DMI/kg of weigh live, and carcass yield of 60.6%, 60.3% and 58.5%, respectively. It is concluded that fish silage acid devil is an excellent alternative in feeding beef cattle as a protein supplement.展开更多
文摘In Mexico the predominant sheep production system is the semi-extensive with grazing during the day and stanchion afternoon and night. Sheep herd are usually small, approximately 10 to 75 heads. The objectives of these systems are savings and marketing of lambs. Meat is the main economic product of this kind, the breeding is long, which do not control the delivery dates and ages of the sheep are not uniform, affecting the demand for the local market （for the months of June and December）. Therefore the aim of this work was implement a technology that allows the grouping of the estrus and therefore group deliveries for batches of uniform lambs. This technology was designed to suppress the estrus and heifers growth promoter of feedlots, this technology is melengestrol acetate （MGA） which is a synthetic progesterone oral administration that it is easy to manage in the food or alone, economic that it does not represent any risk for sheep females of abortive type, evaluating the effect of the MGA on rate of estrus and gestation in sheep. Work developed in the municipality of Charo from Michoac^in State, M6xico, 20 hair sheep divided in two groups of 10 female, group one treated with MGA and group tow was the whitens. 100% of the sheep treated with a dose of 0.45 mg MGA/head/day for 17 days orally, presented estrus grouped in 5-10 days; however only 50% of the sheep of the witness group presented estrus. In the experimental group there was a rate of 70% with a gestation difference time of no more than ten days gestation and witness group 50%. The MGA is an efficient alternative for the producer of sheep when administered 0.45 mg MGA/head/day for 17 days because inhibits the estrus and once withdrawn treatment manifests estrus synch with which get a rate of gestation elevated by natural riding.
文摘Animal nutrition is one of the most important limiting factors in animal production, especially in ruminants, providing proteins being the main constraint, due to the limited availability and high cost of protein sources （oilseed meals）. Currently in the dam ＂El lnfiernillo＂ in Michoacan Mexico, has a large population of devil fish （Pterygoplichthys spp.）, which is an economic and ecological problem, because it is not consumed by humans and causes pollution to be discarded directly into the environment. For that reason the objective of this study was to evaluate the use of silage acid devil fish （SADF） in fattening beef cattle as a protein supplement. SADF is defined as a product semi-liquid or pasty mixed with formic acid, which leads to a decrease in pH to near 4.0. Used 18 young bulls （Bos taurus × Bos indicus） for 60 days with a starting weight of 278.9 ± 51.2 kg, housed in individual pens with food and water ad libitum were randomly assigned to three treatments with different levels of inclusion SADF （0%, 12% and 18%）. They were weighed to the beginning of the experiment and later every 30 days, previous fasting of 24 hours. To determine the food consumption, weigh every day the offered food and the surplus. There were no significant differences （P 〈 0.05） among treatments with different levels of inclusion of SADF with respect to daily weight gain, with values of 952 ± 324, 927 ±322 and 854 ± 307 g/day, respectively. The dry matter intake （DMI） was 8.9, 9.3 and 7.7 kg/day to 0%, 12% and 18% of SADF, respectively. In the same values for feed conversion were 9.34, 10.03 and 9.01 kg DMI/kg of weigh live, and carcass yield of 60.6%, 60.3% and 58.5%, respectively. It is concluded that fish silage acid devil is an excellent alternative in feeding beef cattle as a protein supplement.
