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Relationships between Longevity and Linear Type Traits in Holstein Cattle Population of Southern Africa 总被引:1,自引:0,他引:1
Relationships between longevity and linear type traits were estimated using data on 34,201 cows with lifetime information and linear type scores. The longevity trait considered was the number of lactations initiated and the linear type traits were rump height, body depth, angularity, rear udder height, fore udder attachment, udder depth, fore teat placement and fore teat length. Fixed effects included in the models were herd year, season of calving and herd-date of classification-classifier and days in milk. Age at first calving and age at classification were included as linear and quadratic covariates. Heritability estimates were low for longevity and moderate for most type traits except rump height and fore teat length. All the phenotypic correlations between longevity and the linear type traits were slightly positive (0.01 to 0.09) except the relationships with rump height and fore teat length which were -0.01 and -0.02, respectively. Genetic correlations between longevity and udder traits as well as angularity were moderate to high and positive (0.22 to 0.48). The only notable negative genetic correlations were longevity with body depth and fore teat length (-0.15 and -0.07, respectively). The genetic correlations suggest that selection for udder traits and angularity should improve longevity in the Holstein cattle population. 相似文献
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Thamm DH Rose B Kow K Humbert M Mansfield CD Moussy A Hermine O Dubreuil P 《Veterinary journal (London, England : 1997)》2012,191(1):131-134
Masitinib, a selective tyrosine kinase inhibitor, has previously been shown to enhance the antiproliferative effects of gemcitabine in human pancreatic cancer, demonstrating potential as a chemosensitizer. This exploratory study investigated the ability of masitinib to sensitize various canine cancer cell lines to doxorubicin, vinblastine, and gemcitabine. Masitinib strongly sensitized histiocytic sarcoma cells to vinblastine (>70-fold reduction in IC(50) at 5 μM masitinib), as well as osteosarcoma and mammary carcinoma cells to gemcitabine (>70-fold reduction at 5-10 μM). In addition, several cell lines were sensitized to doxorubicin (2-10-fold reduction at 10 μM). These data establish proof-of-concept that masitinib in combination with chemotherapeutic agents can generate synergistic growth inhibition in various canine cancers, possibly through chemosensitization. The findings justify further investigation into those combinations that may potentially yield therapeutic benefit. 相似文献
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The effects of 6, 10 and 14 days of skip-a-day feed removal during the starter and grower periods on the growth performance
of Ross 308 and Hubbard broiler chickens were studied in a 49-day production period. Ross 308 was superior to Hubbard in weight
gain, market weight and feed utilization but consumed more feed, deposited more abdominal fat and had a higher mortality rate.
Overall, feed removal improved feed efficiency, had insignificant effects on abdominal fatness and mortality rate and reduced
feed intake, weight gain and market weight. On each restricted-feeding regime, the birds gained as much weight as their fully
fed counterparts during the period of resumed full feeding but were unable to compensate fully for the weight loss and were
lighter at the end of the trial. It is suggested that for profitable broiler production under tropical conditions, Ross 308
and skip-a-day feed removal for less than 6 days from 7 to 17 days of age be considered. 相似文献
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K. A. Wirth K. Kow M. E. Salute N. J. Bacon R. J. Milner 《Veterinary and comparative oncology》2016,14(3):281-294
Yunnan Baiyao is a Chinese herbal medicine that has been utilized for its anti‐inflammatory, haemostatic, wound healing and pain relieving properties in people. It has been utilized in the veterinary profession to control bleeding in dogs with hemangiosarcoma (HSA) and has been anecdotally reported to prolong survival times in dogs with this neoplasm. This study evaluated the in vitro activity of Yunnan Baiyao against three canine HSA cell lines after treatment with increasing concentrations of Yunnan Baiyao (50, 100, 200, 400, 600 and 800 µg mL?1) at 24, 48 and 72 h. Mean half maximum inhibitory concentration (IC50) at 72 h for DEN, Fitz, SB was 369.9, 275.9 and 325.3 µg mL?1, respectively. Caspase‐3/7 activity increased in correlation with the IC50 in each cell line which was confirmed by the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL, APO‐BRDU Kit; BD Biosciences, San Jose, CA, USA) assay. VEGF in cell supernatant was also quantified. Overall, the study found that Yunnan Baiyao causes dose and time dependent HSA cell death through initiation of caspase‐mediated apoptosis, which supports future studies involving Yunnan Baiyao. 相似文献
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The effect of housing two Hyline strains of commercial laying hens White Hyline (W-98) and Brown Hyline (Hyline Brown) at
densities of 2, 3 or 4 per cage (1100, 733 or 550 cm2/hen, respectively) was investigated over 3 months. Hyline Brown layers gained more weight, laid more but lighter eggs, utilized
feed more efficiently and had a lower mortality than W-98 layers. Housing birds 2 or 3 per cage resulted in greater body weight
gain, higher egg production, heavier eggs, better feed conversion ratio and a lower mortality than housing them 4 per cage.
There were significant interactions between strain and stocking density for egg production, egg weight, egg output and mortality.
It is suggested that for egg production in semi-arid areas Hyline Brown hens could be used and housed at a density of 733
cm2/hen. 相似文献
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Estimates of (co)variance and genetic parameters of birth, weaning (205 days) and yearling (365 days) weight were obtained using single-trait animal models. The data were analysed by restricted maximum likelihood, fitting an animal model that included direct and maternal genetic and permanent environmental effects. The data included records collected between 1976 and 2001. The pedigree information extended as far back as early 1960s. The heritabilities for direct effects of birth, weaning and yearling weights were 0.36, 0.29 and 0.25, respectively. Heritability estimates for maternal effects were 0.13, 0.16 and 0.15 for birth, weaning and yearling weights, respectively. The correlations between direct and maternal additive genetic effects were negative for all traits analysed. The results indicate that both direct and maternal effects should be included in a selection programme for all the traits analysed. 相似文献
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宫本一 《河北农业大学学报》1991,14(3):62-68
本文研究对于多胎动物利用约束最大似然法(REML)估计父畜、父内窝间和剩余误差的方差组分。以猪达到105公斤体重的日龄(D105)和背膘厚度(ABF)为例,把D105和ABF的记录都调整到以105公斤为基础。采用的混合模型包括出生一年一月(BYM)、猪的性别和母猪产次的固定效应,随机效应是父畜、BYM和父畜内的窝及剩余误差。利用REML来估计父畜的方差组分(0 0,BYM和父畜内的窝方差组分和剩余误差。假定这些方差来源内的每个随机效应相互独立和同一分布,即Var=Iσ_s~2,VasIσ_1~2Var(e)=Iσ_e~2;随机效应间不存在协方差,即COV=0,Cov=0,COV=0。遗传力(h~2)和同窝小猪的共同环境效应(C~2)的估值分别按=和=计算。 C 相似文献
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宫本一 《河北农业大学学报》1990,13(3):105-113
本文论述了利用简化动物模型评价种畜育种值的最佳线性无偏预测(BLUP)法的计算效率。根据本文的模拟数据示例和国外文献资料分析表明,包括父亲和外祖父的简化动物模型与通常的动物模型的BLUP计算比较,对于缩小方程组的大小、节省计算机的内存和减少计算时间等方面的效率都较高,而包括父亲和母亲的简化动物模型的效率不如前者。因此,生产能力测验评价种畜育种值需用较大系列方程时,以采用包含父亲和外祖父的简化动物模型的BLUP法为宜。 相似文献