Genetic Parameters for Milk Yield and Lactation Length of Crossbred Buffaloes from Brazil by Bayesian Inference

The objective of the study was to estimate heritability and repeatability for milk yield (MY) and lactation length (LL) in buffaloes using Bayesian inference. The Brazilian genetic improvement program of buffalo provided the data that included 628 females, from four herds, born between 1980 and 2003. In order to obtain the estimates of variance, univariate analyses were performed with the Gibbs sampler, using the MTGSAM software. The model for MY and LL included direct genetic additive and permanent environment as random effects, and contemporary groups, milking frequency and calving number as fixed effects. The convergence diagnosis was performed with the Geweke method using an algorithm implemented in R software through the package Bayesian Output Analysis. Average for milk yield and lactation length was 1,546.1 +/- 483.8 kg and 252.3 +/- 42.5 days, respectively. The heritability coefficients were 0.31 (mode), 0.35 (mean) and 0.34 (median) for MY and 0.11 (mode), 0.10 (mean) and 0.10 (median) for LL. The repeatability coefficient (mode) were 0.50 and 0.15 for MY and LL, respectively. Milk yield is the only trait with clear potential for genetic improvement by direct genetic selection. The repeatability for MY indicates that selection based on the first lactation could contribute for an improvement in this trait.

Genetic Parameter Estimates for Milk Yield and Lactation Length in Buffalo

The objective of this study was to estimate genetic parameters for milk yield at 244 days and lactation length in graded buffalo cows at the El Cangre Cattle Genetic Enterprise. Data were gathered from 2575 lactations, 1377 buffalo cows, 37 milking units and between 2002-2009 calving years. It was employed the Restricted Maximum Likelihood method (REML) for estimating (co) variance components with multi trait model. Average of milk yield at 244 days and lactation length were 864 kg and 240 days, respectively. Heritability was 0.15 for milk yield and 0.13 for lactation length. Genetic correlation between these traits was 0.63. It was concluded that it is necessary to intensify selection and to increase control of the information of the genetic herds to obtain high precision in the estimates and therefore, obtain bigger genetic progress in of this species in our country.

Application of Reactions Norms in Study of Genotype Environmental Interaction for Milk Yield of Buffaloes

The aim of this study was to estimate genetic parameters for milk yield (MY) in buffaloes using reaction norms. Model included the additive direct effect as random and contemporary group (herd and year of birth) were included as fixed effects and cow age classes (linear) as covariables. The animal additive direct random effect was modeled through linear Legendre polynomials on environment gradient (EG) standardized means. Mean trends were taken into account by a linear regression on Legendre polynomials of environmental group means. Residual variance was modeled trough 6 heterogeneity classes (EG). These classes of residual variance was formed : EG1: mean = 866,93 kg (621,68 kg-1011,76 kg); EG2: mean = 1193,00 kg (1011,76 kg-1251,49 kg); EG3: mean = 1309,37 kg (1251,49 kg -1393,20 kg); EG4: mean = 1497,59 kg (1393,20 kg-1593,53 kg); EG5: mean = 1664,78 kg (1593,53 kg -1727,32kg) e EG6: mean = 1973,85 kg (1727,32 kg -2422,19 kg).(Co) variance functions were estimated by restricted maximum likelihood (REML) using the GIBBS3F90 package. The heritability estimates for MY raised as the environmental gradient increased, varying from 0.20 to 0.40. However, in intermediate to favorable environments, the heritability estimates obtained with Considerable genotype-environment interaction was found for MY using reaction norms. For genetic evaluation of MY is necessary to consider heterogeneity of variances to model the residual variance.

Efficacy of sperm motility after processing and incubation to predict pregnancy after intrauterine insemination in normospermic individuals

Background: Intrauterine insemination (IUI) is widely used to treat infertility, and its adequate indication is important to obtain good pregnancy rates. To assess which couples could benefit from IUI, this study aimed to evaluate whether sperm motility using a discontinuous gradient of different densities and incubation in CO2 in normospermic individuals is able to predict pregnancy.Methods: A total of 175 couples underwent 175 IUI cycles. The inclusion criteria for women were as follows: 35 years old or younger (age range: from 27 to 35 years) with normal fallopian tubes; endometriosis grades I-II; unexplained infertility; nonhyperandrogenic ovulatory dysfunction. Men with normal seminal parameters were also included. All patients underwent ovarian stimulation with clomiphene citrate and human hMG or r-FSH. When one or (at most) three follicles measuring 18 to 20 mm were observed, hCG (5000 UI) or r-hCG (250 mcg) was administered and IUI performed 36-40 h after hCG. Sperm processing was performed using a discontinuous concentration gradient. A 20 microliters aliquot was incubated for 24 h at 37 degrees C in 5% CO2 following a total progressive motility analysis. The Mann-Whitney and Chi-square tests, as well as a ROC curve were used to determine the cutoff value for motility.Results: Of the 175 couples, 52 (in 52 IUI cycles) achieved clinical pregnancies (CP rate per cycle: 29.7%). The analysis of age, duration and causes of infertility did not indicate any statistical significance between pregnancy and no pregnancy groups, similar to the results for total sperm count and morphology analyses, excluding progressive motility (p < 0.0001). The comparison of progressive motility after processing and 24 h after incubation between these two groups indicated that progressive motility 24 h after incubation was higher in the pregnancy group. The analysis of the progressive motility of the pregnancy group after processing and 24 h after incubation has not shown any motility difference at 24 h after incubation; additionally, in couples who did not obtain pregnancy, there was a statistically significant decrease in progressive motility 24 h after incubation (p < 0.0001). The ROC curve analysis generated a cutoff value of 56.5% for progressive motility at 24 h after incubation and this cutoff value produced 96.1% sensitivity, 92.7% specificity, 84.7% positive predictive value and 98.3% negative predictive value.Conclusions: We concluded that the sperm motility of normospermic individuals 24 h after incubation at 37 degrees C in 5% CO2, with a cutoff value of 56.5%, is predictive of IUI success.

Evaluation of a commercially available organic acid product on body weight loss, carcass yield, and meat quality during preslaughter feed withdrawal in broiler chickens: A poultry welfare and economic perspective

The effect of a commercial organic acid (OA) product on BW loss (BWL) during feed withdrawal and transportation, carcass yield, and meat quality was evaluated in broiler chickens. Two experiments were conducted in Brazil. Commercial houses were paired as control groups receiving regular water and treated groups receiving OA in the water. Treated birds had a reduction in BWL of 37 g in experiment 1 and 32.2 g in experiment 2. In experiment 2, no differences were observed in carcass yield between groups. Estimation of the cost benefit suggested a 1: 16 ratio by using the OA. In experiment 3, conducted in Mexico, significant differences on water consumption, BWL, and meat quality characteristics were observed in chickens that were treated with the OA (P < 0.05). These data suggest this OA product may improve animal welfare and economic concerns in the poultry industry by reducing BWL and improving meat quality attributes.

Using Slaughter Weight to Predict Weight and Yield of Primal Cuts of Carcass from Buffaloes

The knowledge of the meat production from different buffalo breeds and their crossings in different feeding systems becomes necessary for the supply of subsidies to whole productive meat chain. Some quantitative carcass traits of Mediterranean buffaloes bulls, finished in feedlot, with initial age of fourteen months and 330 kg live weight, slaughtered with 450, 480, 510 and 540 kg, were evaluated. The diet contained 13% crude protein, 2.68 Mcal digestible energy/kg DM and a roughage : concentrate ratio of 25:75. Regression equations for prediction weight and yield of primal cuts of carcass as a function of slaughter weight were obtained. Carcass dressing percent increased as the slaughter weight increased (49.2; 49.5; 49.7; and 49.9%). The Pistola Style cut weight although increasing linearly in weight (108.2; 117.6; 124.0 and 130.7 kg) as the slaughter weight increased, declined linearly when expressed in relation to cold carcass weight (49.5; 49.0; 48.6 and 48.2%). In this experimental conditions Mediterranean young bulls slaughtered between 450 to 540 kg of live weight showed increasing yields of cold carcass, forequarter and thin flank.