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排序方式: 共有883条查询结果,搜索用时 78 毫秒
171.
de Almeida Daniel Mageste Marcondes Marcos Inácio Rennó Luciana Navajas Pereira Silva Luiz Henrique Martins Leandro Soares Marquez David Esteban Contreras Castaño Villadiego Faider Alberto Velez Saldarriaga Felipe Franco Julian David Castaño Moreno Deilen Paff Sotelo de Moura Felipe Henrique Paulino Mário Fonseca 《Tropical animal health and production》2019,51(1):79-87
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of strategic supplementation in the dry period and dry/rainy transition period on the performance and... 相似文献
172.
Rosalina M. LAPITAN Arnel N. DEL BARRIO Osamu KATSUBE Tomomi BAN-TOKUDA Edgar A. ORDEN Alberto Y. ROBLES Libertado C. CRUZ Yukio KANAI Tsutomu FUJIHARA 《Animal Science Journal》2008,79(2):210-217
The objective of this study was to compare the carcass and meat quality in crossbred cattle and crossbred water buffalo at the same younger age and fed with high roughage in the Philippines. Ten crossbred cattle and 10 crossbred water buffalo, with an average age of 22 months (18–24 months) were used in this experiment. The animals were fed a similar diet, which consisted of 85% Napier or Para grass and 15% concentrate mixture on a dry matter basis, for 180 days before slaughter. Slaughter weight of the crossbred water buffalo was higher (P < 0.05) than that of the cattle, although the dressing percentage was significantly (P < 0.01) lower for the former than for the latter. The estimated lean yield was higher (P < 0.05) in crossbred cattle than crossbred water buffalo. The muscle fiber diameter of loin in buffalo meat was smaller (P < 0.05) than that in cattle. In regard to carcass and meat quality, the crossbred water buffalo was comparable or slightly superior to the crossbred cattle in tenderness, sensory score of color (P < 0.01) and flavor (P < 0.05). These results clearly indicate that at a younger age and even under high roughage‐based fattening rations, crossbred water buffalo are able to produce good quality meat, which will be by no means inferior to that of crossbred cattle in the Philippines. 相似文献
173.
Juan Jethro Silva Santos Yuri Bovi Carvalho Diogo Luiz de Alcantara Lopes Luis Alberto Romano 《Journal of aquatic animal health》2016,28(1):11-20
The yellow clam Mesodesma mactroides (Mesodesmatidae) is a sandy beach bivalve that is distributed from Rio de Janeiro, Brazil, to the south of Buenos Aires province, Argentina. The yellow clam population has been declining in recent decades. To increase our understanding of this species, we evaluated the immunological status of yellow clams collected during different seasons from various areas in the state of Rio Grande do Sul, Brazil. We characterized the hemocytes, determined the differential hemocyte counts (DHCs), calculated the apoptotic index, and evaluated the incidence of parasites in yellow clams through histological analysis. We identified two types of hemocyte (hyaline and granular) that showed significant variation in DHCs among sampling areas during the summer and winter. The apoptotic index only exhibited significant variation during the summer. Histopathological analysis results did not significantly differ among sampling areas. This work demonstrated that environmental variation (e.g., temperature and salinity) associated with anthropogenic actions may be affecting the immune system of yellow clams. However, more studies are needed to determine the full influence of these factors on the yellow clam’s immune system and thus contribute to future management and aquaculture of the species.
Received May 10, 2015; accepted October 28, 2015. 相似文献
174.
Effects of exposure to artificial long days on milk yield,maternal insulin‐like growth factor 1 levels and kid growth rate in subtropical goats 下载免费PDF全文
Horacio Hernández José Alfredo Flores José Alberto Delgadillo Ilda G. Fernández Manuel de Jesús Flores Ángel Mejía José Manuel Elizundia Marie Bedos José Luis Ponce Sergio Ramírez 《Animal Science Journal》2016,87(4):484-491
This study was designed to determine whether any relationship exists between exposure to artificial long days, milk yield, maternal plasma insulin‐like growth factor 1 (IGF‐1) levels, and kid growth rate in goats. One group of lactating goats was maintained under naturally decreasing day length (control group; n = 19), while in another one, they were kept under artificial long days (LD group; n = 19). Milk yield was higher in goats from the LD group than that in the control group (P < 0.05). Maternal IGF‐1 levels at day 57 of lactation were higher (P < 0.05) in goats from the LD group than the levels in the control group and were positively correlated with the total milk yields per goat at days 43 and 57 of lactation (r = 0.77 and r = 0.84, respectively; P < 0.01). Daily weight gain at week 4 was higher (P < 0.01) in kids from the LD group than that in kids from the control group and was correlated with total and average IGF‐1 maternal levels (r = 0.60 and r = 0.60, P < 0.05). It was concluded that submitting lactating goats to artificial long days increases milk yield, plasma IGF‐1 maternal levels and the growth rate of the kids. 相似文献
175.
Carlos Alberto Alves de Oliveira Filho José Augusto Gomes Azevêdo Gleidson Giordano Pinto de Carvalho Camilla Flávia Portela Gomes da Silva Ícaro dos Santos Cabral Luiz Gustavo Ribeiro Pereira Larissa Gomes dos Reis Flávio Moreira de Almeida Lígia Lins Souza 《Tropical animal health and production》2016,48(2):289-295
176.
Alberto Cesarani Ivan Pocrnic Nicol P. P. Macciotta Breno O. Fragomeni Ignacy Misztal Daniela A. L. Lourenco 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(1):40-50
We investigated the effects of different strategies for genotyping populations on variance components and heritabilities estimated with an animal model under restricted maximum likelihood (REML), genomic REML (GREML), and single‐step GREML (ssGREML). A population with 10 generations was simulated. Animals from the last one, two or three generations were genotyped with 45,116 SNP evenly distributed on 27 chromosomes. Animals to be genotyped were chosen randomly or based on EBV. Each scenario was replicated five times. A single trait was simulated with three heritability levels (low, moderate, high). Phenotypes were simulated for only females to mimic dairy sheep and also for both sexes to mimic meat sheep. Variance component estimates from genomic data and phenotypes for one or two generations were more biased than from three generations. Estimates in the scenario without selection were the most accurate across heritability levels and methods. When selection was present in the simulations, the best option was to use genotypes of randomly selected animals. For selective genotyping, heritabilities from GREML were more biased compared to those estimated by ssGREML, because ssGREML was less affected by selective or limited genotyping. 相似文献
177.
A total of 306,698 racing performance data recorded between 1992 and 2002 from 25495 Brazilian Thoroughbred horses was analyzed to estimate the variance components using the Random Regression Model (RRM) compared to the Classical Repeatability Animal Model (CRAM). The performance was evaluated using the race time (in seconds) to run distances of 1000, 1100, 1200, 1300, 1400, 1500 or 1600 meters. The pedigree of each horse was extended as far as possible, with a total of 36,659 animals. The simple correlation between Breeding Value (BV) for the race time estimated by both procedures was high (r = 0.963) when the data were expressed at the mean level of all distances. However, with the RRM it was possible to estimate the genetic parameters and the BV of all animals at the trajectory of each one of the seven distances. Also, results clearly showed that a single BV estimated by CRAM, is neither an adequate nor a sufficient indicator for the selection of the best horses throughout the trajectory of distance performance. We concluded that the RRM procedure is highly recommended for the evaluation of racehorse performance. 相似文献
178.
Daniel Mageste de Almeida Marcos Inácio Marcondes Luciana Navajas Rennó Leandro Soares Martins Faider Alberto Castaño Villadiego Mário Fonseca Paulino 《Tropical animal health and production》2018,50(8):1843-1849
The research aimed to evaluate the effect of replacing soybean meal with soybean grain on the nutritional parameters and productivity of heifers grazing on Urochloa decumbens in the rainy-dry transition period. Forty crossbred heifers with the initial age and weight of 18 months and 292?±?6.1 kg, respectively, were used. The experimental design was a completely randomized design, with five treatments and eight replications. The evaluated treatments were as follows: SM0.5—supply of 0.5 kg/animal/day of soybean meal supplement; SG0.5—supply of 0.5 kg/animal/day of soybean grain supplement; SM1.0—supply of 1.0 kg/animal/day of soybean meal supplement; SG1.0—supply of 1.0 kg/animal/day of soybean grain supplement; MM—only mineral mix ad libitum. The supplement was isoprotein with 350 g of crude protein/kg of dry matter. Supplementation improved the performance of the heifers and this fact can be verified by the higher average daily gain (ADG) and final BW (fBW) of the supplemented animals (P?<?0.10). The two supplemented treatments with 1 kg/day demonstrated similar performance (P?>?0.10), the same happens for the two treatments receiving 0.5 kg/day (P?>?0.10). However, animals receiving 1 kg/day of supplementation had an ADG and final BW higher than animals receiving 0.5 kg/day (P?<?0.10). Supplementation (P?<?0.10) affected the intake of dry matter (DM), organic matter, crude protein, ether extract, non-fiber carbohydrates, total digestible nutrients, and neutral detergent fiber corrected for ash and protein (apNDF). Supplementation improved DM digestibility and all constituents of the diet (P?<?0.10), except for apNDF (P?>?0.10). In summary, it is concluded that multiple supplementations improve the performance of grazing heifers in the rainy-dry transition period and the total replacement of soybean meal by soybean grain does not alter the performance of the animals. 相似文献
179.
Daniel Mageste de Almeida Marcos Inácio Marcondes Luciana Navajas Rennó Lívia Vieira de Barros Carla Heloísa Avelino Cabral Leandro Soares Martins David Esteban Contreras Marquez Felipe Vélez Saldarriaga Faider Alberto Castaño Villadiego Manuela Acevedo Cardozo Roman Maza Ortega Javier Enrique Garces Cardenas Virginia Lucia Neves Brandão Mário Fonseca Paulino 《Tropical animal health and production》2018,50(8):1771-1777
Beef cows’ milk yield is typically determined by measuring milk yield once daily and then doubling this value to estimate daily production. However, it is not known whether this is accurate. Thus, we aimed to determine the association between morning and afternoon milk yield in grazing Nellore cows. Eighty Nellore cows were used, with initial weight of 516.0?±?1.0 kg. The experiment was a completely randomized factorial scheme, with 20 replications and four treatments (i.e., +?or ??pre-partum supplementation in combination with +?or ??post-partum supplementation): PRMM—1 kg of supplement/cow/day for 90 days pre-partum; MMPS—1 kg of supplement/cow/day for 90 days post-partum; PRPS—1 kg of supplement/cow/day for 90 days pre-partum and 90 days post-partum; and MM—only mineral mix ad libitum during pre- and post-partum. Milk was sampled on days 45, 135, and 225 post-partum (early, middle, and late lactation, respectively). No effects were observed of pre- and post-partum supplementation on milk yield (P?>?0.05). The afternoon/morning proportion of 0.45 in the early third of lactation was higher than other stages, which had a proportion of 0.41 (P?<?0.05). Post-partum supplementation increased milk protein in the morning and afternoon milking (P?<?0.05). There was also no effect of pre- and post-partum supplementation on afternoon-morning proportion other milk components (P?>?0.05). We conclude that estimating daily milk production of grazing beef cattle by multiplying a once daily milking amount times two is not accurate. Under the conditions of this study, proportion of total daily production represented by the ratio of afternoon/morning milking was 0.45 in early lactation (first third) and 0.41 in mid- and late lactation. 相似文献
180.