Records on growth traits were obtained from five Midwestern agricultural experiment stations as part of a beef cattle crossbreeding project (NC-196). Records on birth weight (BWT, n =3,490), weaning weight (WWT, n = 3,237), and yearling weight (YWT, n = 1,372) were analyzed within locations and pooled across locations to obtain estimates of breed of sire differences. Solutions for breed of sire...

A procedure was developed to rank AI sires on utility. The utility function considered transmitting abilities for production, udder depth, teat placement; and foot angle, semen cost, timing of costs and revenues, gene flow, and risk. Weights for type traits relative to production and risk aversion were based on the literature. A three-generation planning horizon was used. Utility was expressed ...

Estimates of genetic parameters resulting from various analytical models for birth weight (BWT, n = 4,155), 205-d weight (WWT, n = 3,884), and 365-d weight (YWT, n = 3,476) were compared. Data consisted of records for Line 1 Hereford cattle selected for postweaning growth from 1934 to 1989 at ARS-USDA, Miles City, MT. Twelve models were compared. Model 1 included fixed effects of year, sex, age...

The ability of three mixed linear models to rank sires correctly for dichotomous and ordered tetrachotomous traits was studied using simulated half-sib progeny data. The models differed in the assumptions made regarding homogeneity of residual variance. Ranking ability was assessed by estimating the realized response to truncation selection (20% of the candidates selected) upon sire evaluations...

Several sheep fetuses were thymectomized, and their tails were removed at 58 to 65 days of gestation for tissue culture. Bovine leukemia virus (BLV) antigens were detected in serial culture of tissues from fetuses whose dams and sires were both BLV positive. However, no BLV antigens were detected in serial cultures of tissues from fetuses whose dams were negative but whose sire was positive. Pr...

Materials and methods: Gilt and boar progeny from 8276 litters of a genetic multiplier that used four dam lines and fi ve sire lines were observed for umbilical hernias by 11 weeks of age. Hernias were attributed to birth litter. Odds of umbilical hernia development were calculated using logistic regression and rates were calculated using Poisson regression. Negative binomial models using sire ...

The multiple-trait across country evaluation method is currently used for international genetic evaluation of dairy sires. This method simultaneously combines national estimated breeding value (EBV) of sires in all countries and produces a separate breeding value to be used in each of the 24 countries that participate in the service. The major drawbacks to this method are the large number of ge...

Ability to select service sires that minimize partial or complete losses of pregnancy could have major economic impacts in sheep production systems. This study tested the null hypothesis that survival of potential progeny did not vary with breed type of service sire or among individual rams. Data included 980 ewes on 10 farms; each ewe was pregnant to 1 of 67 rams of 12 breeds. Number of concep...

The hypothesis was proposed that embryonic growth could be influenced paternally in the absence of changes in egg weight or eggshell conductance. Sire families were established by selecting 11 sires based on blood sampling of approximately 50 commercial turkey males. Southern blot analysis was used to identify the most distantly related individuals in the subpopulation. Five hen siblings or hal...

In pork production, the efficiency of dietary protein (AA) use is low, resulting in urinary excretion of large quantities of nitrogen as urea. Use of AA and formation of urea are under enzymatic regulation, suggesting genetic regulation. The current study examined the effects of sire line, sire, and sex on growth characteristics and plasma urea nitrogen (PUN) concentrations in the offspring of ...