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Öğe Comparison of Different Lactation Curve Models of Anatolian Buffaloes(KAFKAS UNIV, VETERINER FAKULTESI DERGISI, 2014) Sahin, Aziz; Ulutas, Zafer; Yildirim, Arda; Aksoy, Yuksel; Genc, SerdarIn this study, eight different lactation curve models were compared by using test day milk yield records belonging Anatolian Buffaloes raised in different Farm conditions between 2011 and 2013. To identify the best lactation curve models of Wood, Cobby and Le Du, Logaritmic Quadratic, Exponential, Parabolic exponential, Quadratic, Inverse Polynomial and Logaritmic Linear mathematical functions were used. The coefficient of determination (R-2) and residual standard deviation (RSD) statistics were used for determination of best fitted model in lactation curve. Logaritmic Quadratic and Quadratic functions are the best goodness of fit model as having the highest R-2 and lowest RSD coefficients. As a result, the parameters are estimated by logarithmic quadratic or quadratic models, for use in breeding programs will make an important contribution to research in this field.Öğe Effect of Various Environmental Factors and Management Practices on Somatic Cell Count in the Raw Milk of Anatolian Buffaloes(ZOOLOGICAL SOC PAKISTAN, 2016) Sahin, Aziz; Yildirim, Arda; Ulutas, ZaferThe aim of this study was to determine the effects of various environmental factors on the somatic cell count (SCC) of Anatolian Buffaloes raised under different herd conditions in Turkey. Data were evaluated according to the stage of lactation (early, mid, and late), herd, lactation month, milking time, and parity. Analysis of the data was performed using the SAS package program. For a one-year period, farms were visited on a monthly basis to collect milk samples from each buffalo, in milkings performed both in the morning and evening. A total of 1200 SCC readings from 100 Anatolian Buffaloes were analyzed using repeated measures. The average SCC was determined to be 134,731 +/- 18,500 cells/ml. The effects of herd, parity, lactation month, milking time and stage of lactation on the SCC value were statistically significant (P<0.05). The mean SCC for morning milking (173,118 cells/ml) was higher than evening milking (148,562 cells/ml). The fourth month of lactation had the highest mean SCC value (186,418 cells/ml), which was statistically different from the values observed during the first, second and fifth months of lactation (P<0.05), as well as the sixth month of lactation (P<0.05). The SCC level was the highest in the first parity (177,844 cells/ml) and the lowest in buffaloes in their third and fourth parity (P<0.05). Mean SCC values were high (P<0.05) for late lactation (203,498 cells/ml), low for mid-lactation (81,975 cells/ml). The SCC was low in herd 6 (37,481 cells/ml), and high in herd 1 (223,000 cells/ml). The significant differences identified between the herds indicated differences in management methods, milking hygiene, and barn conditions. To reduce the SCC levels of milk, while also improving udder health, it is necessary to take certain precautions and measures such as improving milking management; improving hygiene and barn conditions; carrying out milking at uniform intervals; feeding the buffaloes after milking; and implementimg a mastitis control program. In this context, further studies are necessary to investigate and identify the threshold SCC values that are applicable for Anatolian buffaloes and their associated conditions.Öğe Estimates of genetic parameters for different body weights and muscle and fat depths of Karayaka lambs(SCIENTIFIC TECHNICAL RESEARCH COUNCIL TURKEY-TUBITAK, 2016) Aksoy, Yuksel; Ulutas, Zafer; Sen, Ugur; Sirin, Emre; Sahin, AzizIn the current paper the direct additive and maternal genetic effects on birth, weaning (at 90 days of age), and scanning (at 20 weeks of age) weights and muscle and fat depths of the ribeye area in Karayaka lambs were investigated. Analyses were carried out by the restricted maximum likelihood approach, fitting 6 animal models with various combinations of direct and maternal effects. The best model was chosen after testing for improvement in the log-likelihood values. Direct heritability (h(d)(2)) for all traits decreased when maternal genetic effects were included in the models. The maternal heritability (h(m)(2)) ranged from 0.15 to 0.22 for birth weight, from 0.04 to 0.14 for weaning weight, and from 0.08 to 0.16 for scanning weight. The effects of h(m)(2) on muscle depth and fat depth of the ribeye area were not considered due to their insignificance. The permanent environmental effect of the dam was significant for birth, weaning, and scanning weights. Moderate negative genetic correlations (r(am)) between the direct and maternal genetic effects were observed, which were significant for birth (-0.179 and -0.221), weaning (-0.310 and -0.415), and scanning (-0.116 and -0.141) weights. As a result, h(d)(2) and h(m)(2) can be used as selection criteria for birth, weaning, and scanning weights in Karayaka lambs.Öğe Fatty acid and conjugated linoleic acid content of Anatolian buffaloes at different muscle types and slaughter weight(Springer, 2022) Sahin, Aziz; Aksoy, Yuksel; Ugurlutepe, Emre; Ulutas, Zafer; Erinc, Hakan; Aydin, Kenan BurakThis research was performed to detect tissue fatty acid (FA) composition and conjugated linoleic acid (CLA) content in Anatolian buffaloes at different muscle types (MTs) and slaughter weights (SWs). The research was carried out on a private commercial livestock farm in Tokat. The research's animal material comprised 20 Anatolian buffalo calves with approximately 100 kg body weights, weaned at about 150 days of age. Before the experiment started, the calves were randomly divided into two slaughter groups (SW) as low weight (LW=225 kg) and high weight (HW=325 kg). Ten calves from each of the two experimental groups, which were intensively fed, were slaughtered in two different weights. After the slaughtering, FA composition and CLA content of the Semimembranosus (SM), Semitendinosus (ST), and Triceps brachii (TB) muscle tissues of the animals were examined. The study determined that palmitoleic acid (C16:1) and stearic acid (C18:0) were affected by MTs and oleic acid (C18:1) and alpha-linolenic acid (C18:3 n-3) were affected by SW (P < 0.05). The highest CLA was in the ST muscle type (0.298) and the LW group (0.289) of the SW groups (P > 0.05). With the increase of SW (in LW and HW groups), n-6/n3 (SM: 7.783 and 6.533; ST: 8.115 and 7.859; TB: 8.416 and 8.215) (P > 0.05) and PUFA ratio decreased (P < 0.05). The SW increase raised the SFA ratio in the SM muscle (P < 0.05) while lowering it in the TB muscle (P > 0.05). Again, with the increase in SW, AI and TI values increased in SM and ST muscles, while the same index values decreased in TB muscle (P> 0.05). In conclusion, when considering the PUFA/SFA ratio and the beneficial effects of CLAs on human health, ST in the MT and LW groups in SW, and thus ST and LW in MT and SW were prominent in Anatolian buffaloes.Öğe GENETIC PARAMETERS OF FIRST LACTATION MILK YIELD AND FERTILITY TRAITS IN BROWN SWISS CATTLE(WALTER DE GRUYTER GMBH, 2014) Sahin, Aziz; Ulutas, Zafer; Adkinson, Asiye Yilmaz; Adkinson, Robert W.This research was carried out to estimate variance components and genetic parameters for first lactation milk yield (lactation milk yield, 305-day milk yield, lactation length, and dry period) and some fertility traits (calving interval, gestation length and number of services per conception) of Brown Swiss cattle reared at Konuklar State Farm located in Konya province, Turkey. Data were collected on milk yield traits of 3,769 first lactation Brown Swiss cattle during the period from 1990 to 2008. Variance components, genetic parameters, breeding values, and genetic correlations were estimated using multiple trait derivative free restricted maximum likelihood (MTDFREML) fitting an animal model. Heritability estimates were 0.26, 0.25, 0.10, 0.06, 0.07, 0.06 and 0.03 for lactation milk yield (LMY), 305-day milk yield (305 DMY), lactation length (LL), dry period (DP), calving interval (CI), gestation length (GL), and number of services per conception (NSC), respectively. Genetic correlations between milk yield and fertility traits ranged from 0.31 to 0.95 and phenotypic correlations ranged from -0.026 to 0.75. Breeding values were estimated and used to characterize genetic trends across the time period investigated. The results showed that the first lactation milk yield traits can be used as selection criteria for development of effective genetic improvement programme in Turkish Brown Swiss cattle. In addition, the results indicate the essential for scheming an effective schedule for growth of genetic variability to improve the milk yield traits of Brown Swiss cattle in this farm by way of selection.Öğe Genetic trends of body weight and some scanning traits of Karayaka lambs(Agricultural Research Communication Centre, 2018) Ulutas, Zafer; Aksoy, Yuksel; Sahin, Aziz; Sirin, Emre; Sen, Ugur; Kuran, MehmetThis investigation was conducted to estimate the breeding values and genetic trends for body weight (BW), scanning fat depth (SFD) and scanning muscle depth (SMD) of Karayaka lambs (n= 1059) at 140 +/- 3.36 day of age. Experiments were conducted in a nucleus flock of Karayaka sheep under a selective breeding program to increase productivity at research farm of Gaziosmanpasa University between the years 2006 - 2011. Breeding values were estimated with ASREML software. While genetic trend for BW and SMD showed a smooth ascending trend, SFD exhibited a descending trend throughout the experimental period. The genetic trend for BW, SFD and SMD of Karayaka lambs were observed as 0.433 kg / year, 0.00686 mm / year and 0.00786 mm / year, respectively. The results showed that applying of a selection program on BW, SMD and SFD characteristics would increase BW and SMD values and decrease SFD value in Karayaka lambs.Öğe Lactation curve and persistency of Anatolian buffaloes(PAGEPRESS PUBL, 2015) Sahin, Aziz; Ulutas, Zafer; Yildirim, Arda; Aksoy, Yuksel; Genc, SerdarThe aim of this study was to determine the lactation curve traits of Anatolian buffaloes raised under different conditions in farms in Tokat Province, Turkey. Wood's gamma curve parameters were employed to identify the lactation curve types, and values for the parameters beginning yield (a), coefficient of rising (b) and coefficient of decreasing (c) were used to determine the shape and type of lactation curve. All parameters in typical lactation curves were positive, and in the event of one parameter being negative, the curve was considered to be an atypical lactation curve. A total of 690 lactation curves were investigated. It was determined that 406 (58.84%) of these curves were typical, while 90 (13.04%) were concave and 194 (28.12%) of a decreasing type. For typical lactation curves, a, b, c, persistency (S), time after parturition until the peak yield occurs (T-max), maximum daily peak yield (Y-max), and coefficient of determination (R-2) were 7.14 +/- 0.008, 0.85 +/- 2.1, 0.40 +/- 0.001, 2.68, 63.6, 6.41 and 76.33, respectively. For concave lactation curves, values for a, b, c, T-max, Y-max and R-2 were 4.94 +/- 0.42, -0.73 +/- 0.016, -0.23 +/- 0.0038, 95.40, 7.41 +/- 0.004 and 71.68, respectively. For decreasing typical lactation curves, values for a, b, c, T-max, and R-2 were 5.31 +/- 0.0041, -0.15 +/- 0.007, 0.039 +/- 0.0023, 3.89 +/- 0.11 and 79.94, respectively. Parameters predicted by the Wood model within the scope of this study have the potential of being useful for breeding programmes. Further breeding/selection activities could be conducted by using the female Anatolian buffaloes with typical lactation curves.Öğe The application of six different models to estimate the genetic parameters, variance components and breeding values for birth weight of Holstein calves(Taylor & Francis Ltd, 2017) Sahin, Aziz; Ulutas, Zafer; Ugurlutepe, EmreThis research was conducted to determine variance component, genetic parameters and breeding values (EBV) for the birth weight (BW) of Holstein calves. In this context, the direct genetic (sigma(2)(a)), maternal genetic (sigma(2)(m)) and maternal permanent environmental effects, which affect BW, were separately assessed. The multi-trait, derivative-free restricted maximum likelihood programme was used for determining the effect of the genetic parameters by using models that either included or excluded the maternal genetic and/or permanent maternal environmental effects. The estimation of the BW of Holstein calves was optimized by evaluating six different models. The best model was chosen according to the log-likelihood ratio tests. Within the context of the study, a total of 4443 calves were investigated between 1987 and 2006. Among the six different models, model 4 was selected as the best model, since it had the lowest value for the likelihood ratio. The range of the values for direct heritability (h(d)(2)) and maternal heritability (m(2)) were between 0.07-0.13 and 0.04-0.09, respectively. In conclusion, an estimation of the genetic parameters for BW can be used as a selection criteria for Holstein calves.Öğe THE EFFECT OF SOME ENVIRONMENTAL FACTORS ON MILK COMPOSITION OF ANATOLIAN BUFFALOES(UNIV AGRICULTURAL SCIENCES & VETERINARY MEDICINE BUCHAREST, 2016) Sahin, Aziz; Ulutas, Zufer; Yildirim, Arda; Kul, Ertugrul; Aksoy, Yuksel; Ugurlutepe, Emre; Kaplan, YusufThe aim of this study was to determine the composition of raw milk from Anatolian water buffaloes raised under different village conditions in the Tokat province of Northern Turkey. The study materials included 600 milk samples from 120 water buffaloes raised at different farms in 12 separate villages of the Erbaa, Turhal, and Pazar counties in the Tokat Province. The dry matter, nonfat dry matter (or solid non fat), fat, protein, lactose, and casein content of the milk samples were determined. The study results demonstrated that the mean dry matter, nonfat dry matter, fat, protein, lactose, and casein content of the raw milk samples were 16.99 +/- 0.108%, 10.88 +/- 0.036%, 5.98 +/- 0.107%, 4.85 +/- 0.043%, 5.17 +/- 0,021%, and 3.61 +/- 0.036%, respectively. The study data were evaluated according to the water buffaloes' lactation stage, parity, and season by using the SPSS statistical program. It was concluded that the sampling time, parity, village conditions, stage of lactation and calving age had a significant effect (p < 0.05) on the dry matter, nonfat dry matter, fat, protein, lactose, and casein content of raw milk from the Anatolian water buffalo.Öğe The effects of stage of lactation, parity and calving season on somatic cell counts in Anatolian Water Buffaloes(Agricultural Research Communication Centre, 2017) Sahin, Aziz; Yildirim, Arda; Ulutas, Zafer; Ugurlutepe, EmreThe present research was conducted to determine the effects of parity, calving season and stage of lactation on the somatic cell count (SCC) in Anatolian water buffaloes reared different herd conditions. In total, 2,736 SCC readings from 456 Anatolian water buffaloes were analyzed. Data were evaluated by the stage of lactation (early, mid, and late), calving season, and parity with the SPSS package program. Significant effects of calving season, parity, and stage of lactation on SCC were observed (P<0.05). The average SCC was 90,701 +/- 6,372 cells/ml. The results indicated that the SCC of buffaloes were in accordance with, even considerably lower than, the limits indicated in the related regulations of the Turkish Food Codex and those of the European Union Commission. Further studies are necessary to investigate the development of the appropriate threshold values under the conditions of Turkey.Öğe THE EFFECTS OF STORAGE TEMPERATURE AND STORAGE TIME ON THE SOMATIC CELL COUNT OF ANATOLIAN BUFFALOES(Int Buffalo Information Ctr, 2019) Sahin, Aziz; Yildirim, Arda; Ulutas, ZaferThis research examined the effects of storage temperature and storage time on the somatic cell count (SCC) of milk from Anatolian buffaloes, which was measured with the DeLaval cell counter (DCC). Storage temperature and time are among the different factors that potentially affect the SCC of Anatolian buffalo milk. In this context, 20 milk samples were collected from Anatolian Buffaloes and analyzed. The milk samples were divided into two groups according to their measured level of SCC. These two groups were the low score (<= 3.16 cell/ml) group and the high score (>3.16 cell/ml) group. The mean logSCC values of the low score and the high score groups were determined as 2.27 +/- 0.045 and 4.06 +/- 0.019 cells/ml, respectively. In this research, the effects of storage temperature (4 degrees C, 21 degrees C) and storage time (fresh milk, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12 and 24 h) on logSCC were determined to be statistically significant (P<0.01). Thus, increases in storage temperature and storage time were associated with an increase in the logSCC of the milk samples.
