-The 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 and LL indicates that indirect selection using milk yield is a potentially beneficial strategy. The interpretation of the estimated genetic correlation between MY and CI is difficult and could be spurious.

The objective of this study was to evaluate the influence of inbreeding depression on traits of buffaloes from Brazil. Specifically, the traits studied were body weight at 205 and 365 days of age, average daily gain from birth to 205 days (ADG_205), average daily gain between 205 and 365 days (ADG205_365) in Mediterranean buffaloes, and milk yield, lactation length, age of first calving and calving intervals in Murrah buffaloes. Inbreeding effects on the traits were determined by fitting four regression models (linear, quadratic, exponential and Michaelis-Menten) about the errors generated by the animal model. The linear model was only significant (P < 0.05) for growth traits (exception of ADG205_365). The exponential and Michaelis-Menten models were significant (P < 0.01) for all the studied traits while the quadratic model was not significant (P > 0.05) for any of the traits. Weight at 205 and 365 days of age decreased 0.25 kg and 0.39 kg per 1% of increase in inbreeding, respectively. The inbred animals (F = 0.25) produced less milk than non-inbred individuals: 50.4 kg of milk. Moreover, calving interval increased 0.164 days per 1% of increase in inbreeding. Interestingly, inbreeding had a positive effect on age at first calving and lactation length, decreasing age of first calving and increasing lactation length.

Growth curves and weaning stress differences were investigated in Turkish Saanen kids grouped for their weight and Body Mass Index (BMI = weight/height 2 ). Data included 884 records collected from 61 Turkish Saanen kids raised in Canakkale, Turkey. Slopes were calculated for each kid and were analyzed as data using ordinary least squares, and repeated weights for each kid were analyzed using various covariance structures. Differences between male and female kids were small and non-significant before weaning (P = 0.55), while larger (P=0.06) after weaning. Heavy animals grew faster than light animals before weaning (P < 0.01) but lost their advantage after weaning (P > 0.05). Fat animals (high BMI) grew faster than lean animals (low BMI) before weaning (P < 0.01) while the differences slightly diminished after weaning (P=0.04). This may be because light and lean kids were not affected from the weaning shock as much as the heavy and fat kids, which had stuttered growth after weaning. Fit statistics indicated that first-order ante dependence was the best fit covariance structure for these data. Analyses specifying random model and covariance structures did not have an advantage over an approach where slopes were manually calculated and analyzed as data using ordinary least squares.Key Words: turkish Saanen goats, growth curves, repeated data, slopes, covariance structures Zusammenfassung Titel der Arbeit: Wachstumskurven von unterschiedlichen Lebensgewicht-und Körpermasseindex-Gruppen bei türkischen Saanen Ziegenlämmern Die Wachstumskurven und der Absetzstress wurden bei türkischen Saanen Ziegenlämmern untersucht, aufgeteilt in Gewichts-und Körpermasseindexgruppen (BMI=Lebendgewicht/Widerristhöhe 2 ). Einbezogen wurden 884 Lebendgewichtdaten von 61 Ziegen des Versuchsbetriebes der Canakkale Universität. Die Regressionskoeffizienten von Lebendgewichtsdaten der einzelnen Tiere wurden mit unterschiedlichen statistischen Methoden, die Unterschiede in ihrer Kovarianzstruktur aufwiesen, analysiert. Bei den Regressionskoeffizienten wurden vor dem Absetzen im Gegensatz zu der Zeit nach dem Absetzen zwischen den Geschlechtern nicht signifikante geringe Unterschiede festgestellt (P=>0,05). Vor dem Absetzen wuchsen die fetteren, schwereren Tiere (höheren BMI) schneller als die magereren, leichteren (P=<0,01). Nach dem Absetzen verringerten sich diese Unterschiede signifikant zwischen den schweren und leichten bzw. fetten und mageren Tieren. Obwohl sich die Werte der Regressionskoeffizienten nach dem Absetzen in allen Gruppen verringern, sind die Unterschiede bei den schweren d. h. fetteren Tieren zwischen der Zeit vor bzw. nach dem Absetzen gröβer als bei den leichteren Tieren. Für die analysierten Daten zeigte die "first-order ante dependence" Kovarianzstruktur die besten Anpassungsparameter. Die Analysen, welche spezifische Modell-und Kovarianzstrukturen hatten, zeigten keinen Vorteil gegenüber den vorgenannten, wobei die Regressionskurven manuell errechnet und mit der üblichen Methode der kleinsten Quadrate analys...

Drinkable 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.

Abstract. Persistence in dairy animals can be used as selection criteria. Peak value in lactation can be used to predict total lactation production if within lactation persistence is high. This will provide information on early lactation and shorten generation interval. Major purpose of this study was to determine persistency within and between lactations of Turkish Saanen goats in morning, evening and daily milk yields. Two different methods were employed. One used ratios of the succeeding test days as dependent variables. The multivariate analyses indicated that effects of parity (P=0.05), year (P < 0.01), lactation length (P=0.05) and parity by year interaction (P < 0.01) were large. The other approach was to use within correlations and measure changes in milk production in different parities by using repeated measures analysis and modeling covariance structure using compound symmetry. The within correlations can be used as indicators of persistency. Effects of parity, test day and days in milk (DIM), DIM2, ln(DIM) and [ln(DIM)]2 on morning and evening values and total daily milk weights were analyzed to characterize the lactation curve. Values of DIM and repeated measure id number of the goats were added to the model within parity. Within lactation correlations were estimated as 0.22 for morning, 0.28 for evening and 0.27 for daily milk yield. Evening milk tests can alone be used to estimate lactation milk yield, instead of the total test day milk yield. Milk yield increased until lactation four, and decreased in lactation five in morning, evening and daily milk yields. There was a sharp increase from first lactation to second (ranged from 22.0 to 26.8%) and second lactation to third (ranged from 20.0 to 22.2%).

The major purpose of this study was to investigate whether increasing milking frequency for a short period (21 days) increases milk yield and milk components and improves udder health throughout lactation in Turkish Saanen goats. Two groups were formed (control, n = 14, treatment, n = 14); balanced by parity, bodyweight and birth type to make them homogenous. Feeding and management practices were the same for both groups. The treatment group was milked four times a day (4¥) for 21 days after weaning whereas the control group was milked twice a day (2¥). All the animals were milked twice daily thereafter. The pyronin methyl green stain method was used to estimate the somatic cell count (SCC), which is an indication of udder health. This method provided a count that excluded RNA and background noise while including cells with DNA. Repeated measures analyses indicated that overall differences between the 2¥ and 4¥ groups were significant for the morning, evening and total test day milk yields, in that values for the 4¥ group were increased 14.7, 8.8 and 12.1%, respectively. Differences between the groups for SCC were not significant. The results of this study indicate that increasing milking frequency to 4¥, even for a short time (21 days), increases overall milk yield throughout lactation in dairy goats.

The objective of this study was to use pedigree analysis to evaluate the population structure and genetic variability in the Murrah dairy breed of water buffalo (Bubalus bubalis) in Brazil. Pedigree analysis was performed on 5,061 animals born between 1972 and 2002. The effective number of founders (fe) was 60, representing 6.32 % of the potential number of founders. The effective number of ancestors (fa) was 36 and the genetic contribution of the 17 most influent ancestors explained 50 % of the genetic variability in the population. The ratio fe/fa (effective number of founders/effective number of ancestors), which expresses the effect of population bottlenecks, was 1.66. Completeness level for the whole pedigree was 76.8, 49.2, 27.7, and 12.8 % for, respectively, the first, second, third, and fourth known parental generations. The average inbreeding values for the whole analyzed pedigree and for inbreed animals were, respectively, 1.28 and 7.64 %. The average relatedness coefficient between individuals of the population was estimated to be 2.05 %-the highest individual coefficient was 10.31 %. The actual inbreeding and average relatedness coefficient are probably higher than estimated due to low levels of pedigree completeness. Moreover, the inbreeding coefficient increased with the addition of each generation to the pedigree, indicating that incomplete pedigrees tend to underestimate the level of inbreeding. Introduction of new sires with the lowest possible average relatedness coefficient and the use of appropriate mating strategies are recommended to keep inbreeding at acceptable levels and increase the genetic variability in this economically important species, which has relatively low numbers compared to other commercial cattle breeds. The inclusion of additional parameters, such as effective number of founders, effective number of ancestors, and fe/fa ratio, provides better resolution as compared to the inclusion of inbreeding coefficient and may help breeders and farmers adopt better precautionary measures against inbreeding depression and other deleterious genetic effects.

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