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    Effects of udder and teat morphology, parity and lactation stage on subclinical mastitis in Holstein cows
    (Scientific Technical Research Council Turkey, 2003) Uzmay, C; Kaya, I; Akbas, Y; Kaya, A
    The relationships of udder and teat morphology, parity, and lactation stage with subclinical mastitis were investigated in cows raised in herds registered with the Izmir Holstein Breeders Association. Data from 887 cows in 21 herds were used. The udder and teat morphology of the cows was scored. Detection of subclinical mastitis was performed by a hand-held device measuring the electrical conductivity of the milk. It was found that 55.9% of cows had trough-shaped udders, 25.9% had ball-shaped udders, 11.5% had rear-heavy udders, and 6.7% had pendulous udders. Teats were cylindrical in 73.3%, funnel-shaped in 18.8%, pear-shaped in 3.2%, and long and thick in 4.7% of cows. Teats were located squarely in 54.1% of cows, and rear teats were closer to each other compared with the front teats in 45.9%. In multivariate logistic regression analysis, udder and teat morphology, parity, and herd were found to affect significantly (P < 0.001) the probability of subclinical mastitis. The effects of teat placement and stage of lactation were not significant. Cows with trough-shaped udders had the lowest risk of subdinical mastitis, and cows with pendulous udders had the highest risk. When teat morphology was considered, the risk of subdinical mastitis was highest for cows with long and thick teats. The risk of subdinical mastitis for cows with funnel-shaped teats was found to be lower than for cows with cylindrical teats. The risk of subdinical mastitis was found to increase as parity rose.
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    Estimation of breeding values for dairy cattle using test-day milk yields
    (Scientific Technical Research Council Turkey-Tubitak, 2003) Kaya, I; Akbas, Y; Uzmay, C
    The objectives of this study were to estimate genetic parameters and breeding values for test-day (TD) and 305-day milk yields, and to compare the results from TD and 305-day analyses. The data comprised 10,822 TD records from 1103 first lactations of Holstein cows from state farms in the western part of Turkey. Additive genetic, residual and permanent environmental variances, heritabilities and breeding values for 305-day and TD milk yields were estimated by the REML method using animal models. The heritability estimate (0.11) of TD milk yields was lower than the corresponding estimate (0.25) for 305-day milk yields. The product-moment correlations (greater than or equal to 0.97) show that estimated breeding values (EBVs) for TD milk yields are closely correlated with EBVs for 305-day milk yields. Spearman and Kendall rank correlations between rankings of animals for EBVs for TD and 305-day milk yields were also high (greater than or equal to0.97 and greater than or equal to0.86, respectively). Shifts in rank for various top lists of cows and sires ranked by their EBVs for 305-day and TD milk yields show that more extreme changes in ranks occurred in cows than in sires. TD milk yields could be used instead of 305-day milk yield for the genetic evaluation of dairy cattle. Furthermore, using TD yields for genetic evaluations offers more advantages.
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    HPLC - DAD analysis of galanthamine in Galanthus elwesii Hook.
    (Georg Thieme Verlag Kg, 2010) Kaya, I; Polat, Cicek D.; Emir, A.; Sarikaya, B.; Onur, M.; Somer, Unver N.
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    Phytochemical studies on Galanthus fosteri Baker
    (Georg Thieme Verlag Kg, 2010) Unver Somer, N.; Sarikaya, B.; Kaya, I; Onur, M.; Bastida, J.
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    A research on rearing calves with acidified whole milk
    (Scientific Technical Research Council Turkey, 2000) Kaya, A; Uzmay, C; Alcicek, A; Kaya, I
    The objective of this study was to investigate the effect of acidified whole milk fed at 10 % of body weight on calf performance, and the incidence of scours, Twenty Holstein calves were assigned to one of two dietary treatments (whole milk or acidified whole milk), each consisting of 10 calves (5 male and 5 female), from d 5 to d 46 of age for a 42-d trial. Calves were fed either warm whole milk (35 to 37 degrees C) or acidified cold whole milk (acidified with formic acid to pH 4.8 and given at 10 to 20 degrees C) from nipple pails twice daily at 10 % of body weight. The amounts of milk given were adjusted weekly according to body weight, and the calves were gradually weaned, starting at d 40 of age. During the experiment, the calves were offered pelleted starter, alfalfa hay and water For ad libitum intake. All the calves were housed in individual pens. Body weight was recorded weekly. Fecal consistency scores were recorded daily on a scale of 1 to 4 (1=normal, 2=soft 3=runny and 4=watery). intakes of whole milk, starter, and total dry matter from milk and starter were similar between the treatments. Average daily body weight gains (d 5 to 46) for carves Fed whole milk, and acidified whole milk were also similar (427.44 and 459.95 gld, respectively). There was no significant difference in the efficiency of leed conversion between the treatments. Calves fed acidified whole milk exhibited lower fecal consistency scores than did calves led whole milk (2.04 vs, 2.33 during d 5 to 25 and 1.34 vs. 1.46 during d 26 to 46) even though the differences between treatments were not significant. The percentage of calf days with scours was significantly higher for calves fed whole milk than for those fed acidified whole milk for d 5 through 25 (34.28 vs. 18.57 %). In the same period, the percentage of calf days treated for scours was 8.57 % for calves fed whole milk while there was no incidence of scours requiring treatment in carves fed acidified whole milk. The cost of body weight gain was quite high for carves fed whole milk compared with those fed acidified whole milk, due mainly to the costs of veterinary treatment for scours ($ 3.76 vs. $ 2.68 / kg gain).
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    Research on various testing procedures and different methods of estimating lactation milk yield in dairy cattle
    (Scientific Technical Research Council Turkey, 2002) Kaya, A; Uzmay, C; Akbas, Y; Kaya, I; Tumer, S
    This research was carried out to determine the effect of various milk sampling intervals and different methods on the accuracy of estimation of lactation milk yield in dairy cattle. Individual daily milk weights of 599 Holstein, Simmental and Brown Swiss lactations from the Aegean Agricultural Research Institute were used. It was assumed that test-day milk yields were obtained by regular and irregular intervals of 28 d and 56 d, with the irregular intervals having a standard deviation of 5 d. From test-day milk yields, 305 d milk yields were estimated by the Holland (Lactation yield = mean of test day yields x lactation duration (days)) and Test Interval methods. It was found that the bias of estimation increased significantly (P<0.01) as the length of testing intervals increased. The effect of the calculation method on the bias of estimation was also significant (P<0.01). The Test Interval method estimated actual yield more accurately than the Holland method. The difference between the regular and irregular testing intervals with respect to bias of estimation was insignificant. Rank correlations between actual yields and estimated yields were significant (P<0.01) and very high. Therefore, any of the combinations of calculating milk yield in the study can be used to estimate milk yield for the purpose of ranking cows. However, if the aim is to estimate actual yield most accurately, the testing interval should be 28 d. In this case, the Holland or the Test Interval method can be used. If the testing interval is 56 d, the Test Interval method must be used to estimate actual yield.