Covariance functions have been proposed as an alternative to model longitudinal data in animal breeding because of their various merits in comparison to the classical analytical methods.In practical estimation,differe...Covariance functions have been proposed as an alternative to model longitudinal data in animal breeding because of their various merits in comparison to the classical analytical methods.In practical estimation,different models and polynomial orders fitted can influence the estimates of covariance functions and thus genetic parameters.The objective of this study was to select model for estimation of covariance functions for body weights of Angora goats at 7 time points.Covariance functions were estimated by fitting 6 random regression models with birth year,birth month,sex,age of dam,birth type,and relative birth date as fixed effects.Random effects involved were direct and maternal additive genetic,and animal and maternal permanent environmental effects with different orders of fit.Selection of model and orders of fit were carried out by likelihood ratio test and 4 types of information criteria.The results showed that model with 6 orders of polynomial fit for direct additive genetic and animal permanent environmental effects and 4 and 5 orders for maternal genetic and permanent environmental effects,respectively,were preferable for estimation of covariance functions.Models with and without maternal effects influenced the estimates of covariance functions greatly.Maternal permanent environmental effect does not explain the variation of all permanent environments,well suggesting different sources of permanent environmental effects also has large influence on covariance function estimates.展开更多
Turkish Van and Angora cats are one of most important genetic resources in Turkey. The study aimed to evaluate some morphological properties and also behavioural characteristics in both Turkish Van and Angora cats. Th...Turkish Van and Angora cats are one of most important genetic resources in Turkey. The study aimed to evaluate some morphological properties and also behavioural characteristics in both Turkish Van and Angora cats. This research used both literature and the records from the Van Cat Home at Van Cats Research Centre of Yuzuncu Yil University for Turkish Van cats, as well as literature information for Turkish Angora cat. Van cats which have a special place among world cat races have gained appreciation of people with their original eye colors, long white hair and affectionate attitudes. Origin of Turkish Angora cat breeding in Turkey is Ankara province. Angora cat is strong, energetic, kind, known as a moderately long silky haired cat. According to the results of this study and literature, withers height and body length of Turkish Van cat are higher than the Turkish Angora cat, while tale length and breast girth of Turkish Angora cat are higher than the Turkish Van cat. Body weight （g） of female Turkish Angora cat is heavier than the Turkish Van cat, but male Turkish Van cat is heavier than Turkish Angora cat.展开更多
ONE day in 1987, Yang Aiyun received a gorgeous mohair Shawl, a gift her husband Zhang Yongping had brought from the United States. Yang, 58, appreciated the gift and understood her husband’s thinking. As vice direct...ONE day in 1987, Yang Aiyun received a gorgeous mohair Shawl, a gift her husband Zhang Yongping had brought from the United States. Yang, 58, appreciated the gift and understood her husband’s thinking. As vice director of the Research Institute for Tackling the Loess展开更多
基金funded by the Young Academic Leaders Supporting Project in Institutions of Higher Education of Shanxi Province,China
文摘Covariance functions have been proposed as an alternative to model longitudinal data in animal breeding because of their various merits in comparison to the classical analytical methods.In practical estimation,different models and polynomial orders fitted can influence the estimates of covariance functions and thus genetic parameters.The objective of this study was to select model for estimation of covariance functions for body weights of Angora goats at 7 time points.Covariance functions were estimated by fitting 6 random regression models with birth year,birth month,sex,age of dam,birth type,and relative birth date as fixed effects.Random effects involved were direct and maternal additive genetic,and animal and maternal permanent environmental effects with different orders of fit.Selection of model and orders of fit were carried out by likelihood ratio test and 4 types of information criteria.The results showed that model with 6 orders of polynomial fit for direct additive genetic and animal permanent environmental effects and 4 and 5 orders for maternal genetic and permanent environmental effects,respectively,were preferable for estimation of covariance functions.Models with and without maternal effects influenced the estimates of covariance functions greatly.Maternal permanent environmental effect does not explain the variation of all permanent environments,well suggesting different sources of permanent environmental effects also has large influence on covariance function estimates.
文摘Turkish Van and Angora cats are one of most important genetic resources in Turkey. The study aimed to evaluate some morphological properties and also behavioural characteristics in both Turkish Van and Angora cats. This research used both literature and the records from the Van Cat Home at Van Cats Research Centre of Yuzuncu Yil University for Turkish Van cats, as well as literature information for Turkish Angora cat. Van cats which have a special place among world cat races have gained appreciation of people with their original eye colors, long white hair and affectionate attitudes. Origin of Turkish Angora cat breeding in Turkey is Ankara province. Angora cat is strong, energetic, kind, known as a moderately long silky haired cat. According to the results of this study and literature, withers height and body length of Turkish Van cat are higher than the Turkish Angora cat, while tale length and breast girth of Turkish Angora cat are higher than the Turkish Van cat. Body weight （g） of female Turkish Angora cat is heavier than the Turkish Van cat, but male Turkish Van cat is heavier than Turkish Angora cat.
文摘ONE day in 1987, Yang Aiyun received a gorgeous mohair Shawl, a gift her husband Zhang Yongping had brought from the United States. Yang, 58, appreciated the gift and understood her husband’s thinking. As vice director of the Research Institute for Tackling the Loess
