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 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Genotype by Region Interaction on Milk Production Traits of Holstein Crossbred Dairy Cows in Thailand) ผู้เขียน: Mohammed Endris,  ดร.ศรเทพ ธัมวาสร, ศาสตราจารย์ , ดร.พรรณวดี โสพรรณรัตน์, รองศาสตราจารย์ , ดร.สมเกียรติ ประสานพานิช, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractThis study was designed to examine the existence of a genotype ? region interaction on milk production traits in Holstein crossbred dairy cows in Thailand. The data set for this study was provided by Department of Livestock Development of Thailand. The data were divided into five regions (Central, East, North, Northeast and West). The factors having genotype ? region interaction on milk production traits were region, year-season of calving, breed group and breed group ? region interaction. The investigated traits were actual total milk yield (ATMY), 305 d milk yield (MY305) and adjusted 305 d milk yield (AJ305), respectively. The breed group of cow had a significant (P < 0.05) effect on MY305 and a highly significant (P < 0.01) effect on ATMY and AJ305 while the effect of year-season of calving and region had very highly significant (P < 0.001) effects for all the studied traits. Breed group ? region had a highly significant interaction (P < 0.01) for the milk production traits. The estimated heritability for the milk production traits ranged between 0.17 to 0.24 for the Central region and 0.29 to 0.57 for the Eastern region. It was suggested that the performance of breed group of cows from different regions should differ significantly or there was a genotype ? region interaction in this particular study. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Estimation of Direct Genetic Effects on Milk Yield and Lactation Length in the Aownoi Dairy Cooperative) ผู้เขียน:Mohammed Endris, ดร.ศรเทพ ธัมวาสร, ศาสตราจารย์, Chaiwat Wongwan, ดร.พรรณวดี โสพรรณรัตน์, รองศาสตราจารย์, ดร.สมเกียรติ ประสานพานิช, รองศาสตราจารย์ สื่อสิ่งพิมพ์:pdf AbstractThis study aimed to estimate the direct genetic effects on actual milk yield and lactation length of Holstein crossbred dairy cows in the Aownoi Dairy Cooperative. The data comprised 869 lactation records from 850 cows that had calved during 2009–2010. The data were analyzed by the Restricted Maximum Likelihood Method and applying the Average Information Algorithm (AIREML) using univariate analysis. The factors having a direct effect on actual milk yield and lactation length were the year-season of calving (YS), the breed group of the cows and the lactation number. The investigated traits were lactation length and actual milk yield. The results showed that the overall mean (? SE) for milk yield and lactation length was 4,484.84 ? 13.60 kg.cow-1.lactation-1 and 376.94 ? 0.34 d, respectively. The lactation number had a signifi cant effect on the actual milk yield but there was no signifi cant effect of breed group, lactation number and year-season of calving on the lactation length. Estimates of heritability for the actual milk yield and lactation length were 0.22 ? 0.08 and 0.26 ? 0.09, respectively. |
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