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Öğe A NEW SELECTION PROCEDURE IN ANIMAL BREEDING: CLASSIFICATION, ERROR RATES AND COMPARISON WITH BLUP(Pakistan Agricultural Scientists Forum, 2012) Pala, A.Classification techniques can be used as an alternative to the selection index, especially for indirect selection of multiple traits. Prior information for this technique provides to increase accuracy of selection. Two sets of simulations were used to estimate the error rates of the classification techniques in selection of livestock and to compare the method with the animal model, an example of Best Linear Unbiased Predictions (BLUP). The first set of analyses considered the traits milk yield, milk fat, milk protein and somatic cell count (SCC). Frequent milking was simulated and the high and low means were created within the standard deviation limits. Using these different means, observations and standard deviations, various scenarios were produced to simulate various data sets for validation to check how correctly the classification method worked. The different scenarios included A. Same means and sigma, different observations, B. Different means and observations, same sigma, C. Different means (standardized) and observations, same sigma, D. Same means, different sigma (+/- 5 for milk yield, milk fat and protein, +/- 3 for SCC) and observations, E. Same means, different sigma (+/- 10 for milk yield, milk fat and protein, +/- 6 for SCC) and observations. The procedure selected the correct animals and produced a very low error rate in almost all simulations. In the second set of simulations, the traits considered were milk yield and SCC for two goat breeds, Saanen and German Fawn. A total of 10 000 dams, 3174 sires and 10 000 progeny were simulated. The family variance was 4.5. The sires had 3.15 progeny on average, and sires had minimum 1 and maximum 15 progeny. Estimated breeding values from the MTDFREML (Multi Trait Derivative Free Estimated Maximum Likelihood) program were used in the culling decisions. Animals selected using the animal model of BLUP with MTDFREML and animals selected using the classification method with SAS were analyzed employing the rank correlation, and the calculated value was very high 0.99 (P<0.01). If used with the necessary standardizations, the method seems promising enough to be considered as an alternative to existing selection methods and a new method for indirect, multiple trait selection in animal breeding. In addition, the method can be used in cases (no extensive pedigree, small number of animals/sires etc.) where it is difficult to calculate correct genetic parameters.Öğe A new selection procedure in animal breeding: Classification, error rates and comparison with blup(2012) Pala, A.Classification techniques can be used as an alternative to the selection index, especially for indirect selection of multiple traits. Prior information for this technique provides to increase accuracy of selection. Two sets of simulations were used to estimate the error rates of the classification techniques in selection of livestock and to compare the method with the animal model, an example of Best Linear Unbiased Predictions (BLUP). The first set of analyses considered the traits milk yield, milk fat, milk protein and somatic cell count (SCC). Frequent milking was simulated and the high and low means were created within the standard deviation limits. Using these different means, observations and standard deviations, various scenarios were produced to simulate various data sets for validation to check how correctly the classification method worked. The different scenarios included A. Same means and ?, different observations, B. Different means and observations, same ?, C. Different means (standardized) and observations, same ?, D. Same means, different ? (±5 for milk yield, milk fat and protein, ±3 for SCC) and observations, E. Same means, different ? (±10 for milk yield, milk fat and protein, ±6 for SCC) and observations. The procedure selected the correct animals and produced a very low error rate in almost all simulations. In the second set of simulations, the traits considered were milk yield and SCC for two goat breeds, Saanen and German Fawn. A total of 10 000 dams, 3174 sires and 10 000 progeny were simulated. The family variance was 4.5. The sires had 3.15 progeny on average, and sires had minimum 1 and maximum 15 progeny. Estimated breeding values from the MTDFREML (Multi Trait Derivative Free Estimated Maximum Likelihood) program were used in the culling decisions. Animals selected using the animal model of BLUP with MTDFREML and animals selected using the classification method with SAS were analyzed employing the rank correlation, and the calculated value was very high 0.99 (P<0.01). If used with the necessary standardizations, the method seems promising enough to be considered as an alternative to existing selection methods and a new method for indirect, multiple trait selection in animal breeding. In addition, the method can be used in cases (no extensive pedigree, small number of animals/sires etc.) where it is difficult to calculate correct genetic parameters.Öğe A Research on the Problems, Tendencies and Social Structure of Students of Agricultural Faculties(Univ Namik Kemal, 2006) Demir, A.; Pala, A.; Baytekin, H.Social statues, tendencies and plans of students of agricultural faculties were investigated by a survey that had 21 multiple choice and 16 fill in the blanks questions. Only 10 out of 20 Faculties of Agriculture permitted the survey. The surveys were mailed to the universities and the completed 1845 survey forms were received by mail, between March 1st and May 15th, 2005. The data were analyzed using SAS V8.2 and odd ratios were calculated. According to the survey results, 64% of the students were from cities. 87% of the students stated that the education should emphasize the application more. This is because most of the students from cities are not exposed to agricultural practices. 72% of the students fear that they will be unemployed for a long time after graduation. The reason seems to be the excessive number of agriculture engineers and the negative public view on graduates of Faculty of Agriculture. Students who plan to work in private industry believed more in the benefits of education and followed the agricultural publications more closely compared to those who plan to work in a government office or to those who believe they will be unemployed for a long time (P< 0.01). Among the participants, only 6 % referred to agriculture as their ideal profession.Öğe Body mass index slopes of growth and fat content under different feed restrictions in broiler chickens(Eugen Ulmer Gmbh Co, 2008) Mendes, M.; Pala, A.; Dincer, E.Major purpose of this study was to investigate the differences between three feeding regimes, namely ad libitum (AD), %20 restricted feeding based on ad libitum (RF) and fasting between 09.00 AM and 15.00 PM (NF), for Body Mass Index (BMI) and weight slopes and for percent fat content in broiler chickens. The data was collected from 60 Ross 308 line male and female chickens. BMI and weight slopes were calculated for each bird and were analyzed as data using ordinary least squares in addition to repeated measures analysis for acidity, dry matter and fat percent. The regression coefficient of first week BMI values on slopes was -0.276 +/- 0.023 (P<0.001). The AD group had the steepest slopes followed by RF and the NF group when the slopes were calculated using BMI values (P<0.01) or when the slopes were calculated using weight (P<0.01). The regression coefficient of first week weight on the slopes was 0.602 +/- 0.267 (P=0.024) and that of first week's BMI on weight slopes was -5.58 +/- 3.5 (P=0.679). Differences between breast and rump were significant in acidity and dry matter (P=0.00). Overall, the AD group meat had more fat percentage compared to the other groups and the differences were significant (P<0.05). These suggest that heavy animals tend to have higher BMI values and fat percentage, especially with ad libitum feeding.Öğe Effects of animal welfare on sensory acceptance scoring of yogurt(Taylor & Francis Ltd, 2012) Pala, A.; Atakisi, G.Welfare of farm animals can be increased greatly if the animal producers are convinced that increased welfare is useful in terms of product quality. Major purpose of this study was to investigate whether animal welfare changed consumer acceptance and scoring of reduced-fat and plain yogurts (PYs) with or without knowledge of the animal welfare. Four products were used, PY made from whole milk collected from high welfare (HW) farm cows, PY from low welfare (LW) farm cows, low-fat (LF) yogurt from HW farm cows and LF yogurt from LW farm cows. Three evaluations were carried out in the Canakkale Onsekiz Mart University campus; tasting yogurt without labels (Test 1), expectation scoring based on pen and paper (Test 2) and tasting with labels and information on the welfare and fat content (Test 3). In Test 1, the subjects accepted the HW better than LW, and PY better than LF yogurt without the knowledge of the yogurts origin or fat content. The taste seems to direct the subjects scoring towards more fat without the worries related to weight loss. In Test 2, subjects scored LF yogurt higher than PY, which was the opposite of Test 1, but they scored HW higher than their Test 1 scores, which were consistent rank wise. This clearly shows that the subjects participating in the study were interested in LF yogurt consciously but liked that taste of the PY better and were also interested in HW products both in terms of taste and ethics. Some of the differences which were not significant in first two tests were highly significant in Test 3 (P<0.01), which means that the scores were more distinctive among the different products, fortified by both information and taste. The PY-HW yogurts were scored the highest, followed by the LF-HW yogurt samples, the PY-LW yogurts and finally the LF-LW yogurts. This illustrates that the taste buds of the subjects were able to affect scoring significantly (PY scored higher than LF yogurt) and information regarding the fat content did not make enough of a difference to change the ranking from the first test. Sensory perceptions regarding animal welfare were strengthened when sensory input was supported with information provided on animal welfare. In all the three tests, the subjects scored the HW yogurts higher than LW yogurts regardless of the fat content, whether they knew the labels or not. However, information provided on welfare increased the consumer scoring significantly, indicating that HW products should be advertised and labelled clearly to increase consumer sensory acceptance and willingness.Öğe Effects of goat social rank on kid gender(Czech Academy Agricultural Sciences, 2007) Tolu, C.; Savas, T.; Pala, A.; Thomsen, H.Mechanisms of gender ratio in progeny are complex and the fine details are still largely unknown, even in mammals. Though the 50116 ratio of males and females is expected, various factors have been shown to be effective in diverting the ratio from the expected. In this study, dominance index, effects of sire, age of dam, birth type and year of birth on the gender ratio of Turkish Saanen goat kids were investigated in a full model. The analysis indicated that dominance index (DI) of the dam had a significant influence on the gender ratio of kids (P = 0.036). Certain sires tended to father female descendants repeatedly and the dams with high dominance index gave birth to male kids. Effects of sire on kid gender approached significance (P = 0.094). Age of dam, year and birth type were insignificant.Öğe Effects of small-diameter silver nanoparticles on microbial load in cow milk(Elsevier Science Inc, 2012) Yildiz, N.; Pala, A.Controlling bacterial growth in fluid milk is of economic interest, and supplemental methods to stop or reduce bacterial growth before and during the cooling chain may be valuable. Silver is effective in controlling growth of single-celled organisms, but has no effect on tissue cells. Smaller diameter (6-8 nm) silver nanoparticles were produced, with purity over 99.99% (no chemical reaction used in the process), by using a terminated gas condensation principle. The first trial investigated effects of time, temperature, and accelerating voltages on total aerobic bacteria count in control milk and milk treated with silver nanoparticles. Metal braids were coated with silver nanoparticles using 3 accelerating voltages, 0, 100, and 200 V, the results of which indicated that the braids coated using 100 V (AgNP100) were optimal. The AgNP1.00 particles were effective at all treatment temperatures and durations except for 10 h, which indicated that the treated milk could be used after 10 h for other dairy products such as yogurt, which require microbial activity. The second experiment investigated the effects of silver nanoparticles on counts of yeasts and molds, coliform bacteria, Escherichia coli, and Staphylococcus aureus in cow milk by treating milk with AgNP100 braids at 22 degrees C for 1 h. Inductively coupled plasma mass spectrometry analyses indicated that the maximum amount of silver found in the AgNP100-treated milk was 6.1 mu g/L, which is below the safety limits. Counts in milk samples containing the nanoparticle-coated braids were lower for all yeasts and molds and bacteria investigated compared with the control milk samples, which were kept under the same conditions but without; the braids. The differences were significant for coliforms, Escherichia coli, and Staphylococcus aureus but not for yeasts and molds, although ranking of the counts (AgNP100 < initial load < control) were the same for all microorganisms. Small-diameter, silver nanoparticle-coated braids can stop or reduce bacterial growth in fluid milk. Silver nanoparticles inhibited microbial growth and may be useful in complementing the cooling chain and the thermal processes. These results warrant more research on the sensory properties and long-term safety of the use of silver nanoparticles in dairy products.Öğe Productive and reproductive traits in Murrah breed from Brazil(Int Buffalo Information Ctr, 2013) Ramos, Alcides Amorim; Malhado, C. H. M.; Malhado, A. C. M.; Carneiro, P. L. S.; Souza, J. C.; Pala, A.Major objective of this study was to estimate heritability and genetic correlations between milk yield (MY) and calving interval (CI) and lactation length (LL) in Murrah buffaloes using Bayesian inference. The database used belongs to the genetic improvement program of four buffalo herds from Brazil. To obtain the estimates of variance and covariance, bivariate analyses were performed with the Gibbs sampler, using the program MTGSAM. The heritability coefficient estimates were 0.28, 0.03 and 0.15 for MY, CI and LL, respectively. The genetic correlations between MY and LL was moderate (0.48). However, the genetic correlation between MY and CI showed large HPD regions (highest posterior density interval). Milk yield was the only trait with clear potential for genetic improvement by direct mass selection. The genetic correlation between MY-LL indicates that indirect selection using milk yield is a potentially beneficial strategy. The interpretation of the estimated genetic correlation between MY-CI is difficult and could be spurious.Öğe Sensory properties of drinkable yogurt made from milk of different goat breeds(Wiley, 2006) Uysal Pala, Çiğdem; Karagül Yüceer, Yonca; Pala, A.; Savaş, TürkerDrinkable yogurts made from different goat breed milk and made with normal and probiotic cultures were evaluated for their sensory characteristics. Milk of Turkish Saanen, Maltese and Turkish Hair goats obtained during the beginning, middle and end of lactations were used to produce drinkable yogurt. Using descriptive sensory analysis technique, common terms were developed as goaty, creamy, fermented, cooked, throat burn, sweet, salty, sour and astringent. Breeds, lactation periods and using regular and probiotic types of starter cultures affected the sensory characteristics of drinkable yogurts. Drinkable yogurts made by cow milk had weaker intensities of flavor attributes including goaty, creamy, throat burn and salty than that made by goat milks of the three breeds. Drinkable yogurts made from Turkish Saanen breed had more goaty flavor than those made from Turkish Hair and Maltese goat breeds. The products made by milk provided at the end of lactation period had the highest intensities of goaty flavor. In addition, the intensities of goaty, creamy and cooked flavors in the products made by regular yogurt cultures were higher than those of drinkable yogurts with probiotic cultures.
