Yazar "Kaygisiz, Ali" seçeneğine göre listele

Listeleniyor 1 - 3 / 3
  • Küçük Resim
    Öğe
    Breeding Value Estimation of Dairy Cattle Using Test Day Milk Yields for Brown Swiss Cows Reared at Ulas State Farm
    (Medwell Online, 2008) Çilek, Süleyman; Kaygisiz, Ali
    In this study, it was aimed to calculate genetic parameters of 305 day milk yield and breeding value estimation of Brown Swiss Cattle reared on Ulas State Farm. Later, analysis results were compared. In this study, 830 first lactation records of daughter sired by 58 bulls that had at least 5 daughters were used. Additive genetic variance, error variance, permanent variance, environment variance, heritability, repeatability and breeding value were estimated using REML animal model. Heritability of test day milk yields (0, 10) was higher than the heritability of 305 day milk yield (0, 02) Correlation between breeding values estimated using test day milk yields and breeding value of 305 day milk yield was found statistically significant (p<0.01) and high level (0.862). In estimation of breeding value for test day milk yields and 305 day milk yield, Spearman and Kendall correlations between rankings of bulls were found 0.853 and 0.662 and statistically significant (p<0.01). According to results of this study, in genetic evaluation of dairy cows, test day milk yields should be used instead of 305 day milk yield. Furthermore, in genetic evaluation of dairy cows, there are advantages for using test day milk yields. Test day milk yields ought to be taken into consideration in early culling and selection of cows for milk yield.
  • Küçük Resim
    Öğe
    Estimates of Genetic Trends for 305-Days Milk Yield in Holstein Friesian Cattle
    (Medwell Online, 2009) Bakir, Galip; Kaygisiz, Ali; Cilek, Suleyman
    The purpose of this study was to estimate the trends components of 305-days milk yield in Holstein Friesian Cattle Holstein cows raised at the Ceylanpinar state farm in Turkey between 1986 and 2007 years. The phenotypic, genetic and environmental trends for 305-days milk yield were found to be 106.91, 13.42 and 93.49 kg year(-1), respectively. Despite, there was a correct decision in selection environmental factors affected yield more. In this respect, continuing the improving environmental factors which is composed of maintenance, feeding, milking practices and barn is recommended.
  • Küçük Resim
    Öğe
    Milk Yield Traits of Holstein Cattle Reared at Tahirova State Farm in Balikesir Province in Turkey
    (Medwell Online, 2009) Bakır, Galip; Kaygisiz, Ali; Çilek, Süleyman
    In this study, effects of environmental factors on milk yield and milk yield characteristics of Holstein cows raised at Tahirova state farm in Balikesir province of Turkey have been investigated. A total of 1302 milk records obtained between 2000 and 2007 were used in this study. As milk yield traits, lactation duration, lactation milk yield, 305 days milk yield and dry period were investigated. Effect of environmental factors on milk yield traits was analyzed by using the least square means method. The least square means for the lactation duration, lactation milk yield, 305 days milk and dry period yield were 331.74 +/- 1.55 days, 7574.39 +/- 55.22 kg, 6810.14 +/- 56.38 kg and 79.47 +/- 0.90 days, respectively. The effects of calving year on lactation duration, lactation milk yield, 305 days milk yield and dry period were much significant (p<0.01). Effect of calving season on lactation duration was significant (p<0.05). Effect calving age on lactation duration and lactation milk yield was significant (p<0.05, p<0.01). The effects parity on lactation duration, lactation milk yield, 305 days milk yield and dry period were significant (p<0.01-0.05). It can be said that Holstein cattle have quite well milk yield and are raised successfully on Tahirova state farm and under conditions of west Anatolia in Turkey. To obtain much higher milk yield in this farm, true selection for milk yield should be done and better feeding, care and management should be done.