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A comprehensive dynamic simulation model was developed to describe a community-based breeding program for the Menz sheep population of Ethiopia. Selection of male and female animals based on their own and maternal performance was simulated. The breeding goal traits were 6-mo weight, preweaning survival, and fertility rate. The model input data were obtained from the flock book, questionnaires, and references. The simulation model used a mix of deterministic and stochastic procedures to model the complex system. In the baseline scenario, the proportion of selected male and female animals varied between 20 and 30% and between 70 and 80%, respectively. A reasonable annual genetic gain was predicted for the breeding goal traits at the village level. For 6-mo weight and preweaning survival rate, the annual genetic gain varied from 0.213 to 0.214 kg and 0.255 to 0.256%, respectively. For fertility rate, an annual genetic gain of 0.063% was obtained. The predicted rate of inbreeding per year was between 0.094 and 0.116%. Furthermore, a scenario analysis was conducted by varying the proportions of selected animals. Annual genetic gains of 0.230 kg, 0.277%, and 0.069% were obtained for 6-mo weight, preweaning survival rate, and fertility rate, respectively, when the proportion of selected male and female animals decreased by 10%. The annual genetic gains decreased to 0.198 kg, 0.236%, and 0.059%, respectively, when the selection proportion of male and female animals increased by 10%. The lowest rate of inbreeding per year, ranging from 0.065 to 0.079%, was achieved when the selection proportion of selected male and female animals increased. The model is relevant for the step-by-step evaluation of more than one round of selection. It is flexible and usage driven. The model is a valuable tool to design different population structures and can be easily expanded to adopt different breeding strategies. Hence, the system dynamics modeling approach is a potential tool to describe complex breeding programs.

Covariance components and genetic parameters were estimated for birth weight (BiW); adjusted weights at 4, 7, 12, and 18 mo; and ADG between 0 and 4 mo, between 4 and 7 mo, between 7 and 12 mo, and between 12 and 18 mo. Additionally, reproductive traits, calving interval, and age at first calving were analyzed, together with traits measured by ultrasound: loin eye area, deep fat mean, back fat, and rump fat. Analyses were performed using an animal model, considering the fixed effects of the farm (n= 37), year and month of birth, sex, calving number (1 to 7), season (dry and rainy seasons), region (North Coast, Andean Region, and Oriental Savannas), and conception (natural mating or AI), whereas the age of the cows at calving was considered a polynomial covariate with linear and quadratic effects. Three different models were used to find the one with the best fit for each trait: a single-trait model with an additive direct genetic effect, a single-trait model with additive direct and maternal genetic effects, and finally, a multitrait model with an additive direct genetic effect. For the growth traits, the heritability was between 0.24 and 0.47, with the lowest value for weight at 7 mo and the greatest value for BiW, and the maternal heritability was found to be between 0.15 and 0.21 but did not decrease later on. The correlation between direct and maternal effects was high and negative (−0.59 to −0.76). With ultrasound traits, a model with only direct effects was used. The heritability was between 0.13 and 0.28 for back fat and loin eye area, respectively. The heritabilities for deep fat mean and rump fat were similar, being 0.19 and 0.21, respectively. The reproductive traits showed high residual variance. In particular, the heritability of calving interval was low (0.06). The results showed that the growth traits have an important genetic component, which is a favorable indicator for obtaining improvement progress in the zebu Brahman breed for beef production in tropical regions of Colombia. The maternal effects influenced the weight performance from 4 to 18 mo and should be taken into account in genetic analyses. In general, the direct heritability of medium magnitude estimated for growth and traits measured by ultrasound suggests that individual selection for these traits will be effective.

The aim of this study was to estimate genetic parameters for coat color in horses. Besides defining coat color classes (gray, chestnut, bay, and black), the phenotypes were also measured quantitatively according to standardized international procedures (Commission Internationale de l'Eclairage L*, a*, b*), where L* describes lightness, a* describes color saturation from red to green, and b* describes color saturation from yellow to blue. The total color saturation was derived from a* and b* and referred to as Chroma. A total of 294 horses from the breeds Lipizzan, Nonius, Arabian Pure Bred, Shagya Arabian, and Gidran were measured at neck, shoulder, and belly. Heritabilities (within and between breeds or color classes) and repeatabilities were estimated using REML from univariate animal models defined separately for gray and nongray horses. For gray horses, the estimated within-breed heritabilities for L* ranged from 0.45 to 0.49 and for a*, b*, and Chroma from 0.09 to 0.52, indicating moderate polygenic effect. For nongray horses, between-color class heritabilities were high (0.70 to 0.85) and within-color class heritabilities were negligible (except for L* measured on neck and belly, 0.21 and 0.34, respectively). Additionally, the importance of L* was described by the relation with the total melanin content of horse coat hair; for gray and nongray horses, a strong negative linear relationship was detected (P< 0.01). The spectrometric measures and the results of this study demonstrate a possible approach to the estimation of the polygenic component involved in coat color inheritance.

Abstract: A survey in Burundi, Rwanda, Tanzania and Uganda was conducted in order to determine the different production systems under which Ankole cattle are currently kept. Additionally, selection criteria of livestock keepers were documented. In Burundi, Rwanda and parts of Uganda, livestock keepers are sedentary and herds are small, whereas in the other areas Ankole cattle are kept in large herds, some of them still under a (semi-)nomadic system. Milk is the main product in all areas, and is partly for home consumption and partly for sale. Although the production systems vary in many aspects, the selection criteria for cows are similar. Productive traits such as milk yield, fertility and body size were ranked highly. For bulls, the trait ‘growth’ was ranked highly in all study areas. Phenotypic features (coat colour, horn shape and size) and ancestral information are more important in bulls than in cows. The only adaptive trait mentioned by livestock keepers was disease resistance. In areas of land scarcity (Burundi, Rwanda, western Uganda), a clear trend from pure Ankole cattle towards cross-bred animals can be observed.

The objectives of this study were threefold: 1) estimation of additive and dominance genetic variances for fertility traits for Austrian Simmental and Brown Swiss dairy cattle; 2) use of method ℜ and the preconditioned conjugate gradient compared to solving for method ℜ by second-order Jacobi iteration; and 3) study of the impact of inclusion of parental subclass effects on solutions for other random effects. Dominance variances were modeled for the inseminated cow and ranged from 0.32 to 1.36% of total variance. These values were similar to values for additive effects, which were approximately 1% of total variance. Convergence was clearly improved with preconditioned conjugate gradient and number of extrapolations reduced. Variance for permanent environment under a model without dominance could be split into a new estimate of permanent environmental variance and parental subclass variance. Solutions for parental subclass dominance effects were approximately proportional to permanent environment effects, but highly dependent on the number of animals contributing dominance relationships, especially full-sibs and three-quarter-sibs. For animals with a lot of dominance information (full-sibs, three-quarter-sibs, cousins), permanent environment and parental subclass dominance effects were nearly independent. Changes in additive effects were negligible, probably because both variances for parental subclass dominance effects and additive genetic effects were very small compared with residual variance.

Multitrait, across-country evaluation procedures were adapted to improve reliability of survival breeding values by combining direct information with yield and functional traits: milk persistency, somatic cell count, fertility (male and female), and calving ease (direct and maternal). A set of bulls was selected from the Austrian Simmental population based on mean original reliabilities of at least 0.50 for yield traits or of at least 0.20 for functional traits. Only breeding values above these limits were retained. The breeding values were deregressed, assuming that they were obtained by single-trait, sire-maternal grandsire models. An expectation-maximization restricted maximum likelihood algorithm based on the multitrait, across-country evaluation equations was used to compute genetic correlations among all of these traits. These equations were solved, and the reliabilities of the solutions were also estimated. Mean rank correlation between direct and combined breeding values was 0.85 with values as low as 0.67 for the group of youngest bulls. Direct (original), indirect, and combined reliabilities were compared to appreciate the impact of our procedures on improvement of reliability of survival breeding values. This improvement, dependent on the level of reliability of direct and indirect information, could be up to 0.24 for animals with low direct reliability and high indirect reliability. For young bulls born in 1992 without reliable direct survival information but with already reliable information on yield and functional traits, mean reliability improvement was 0.13. For all bulls this value was still 0.06.

A method is presented to treat gametes as homozygous diploid individuals allowing their inclusion into the relationship matrix between animals. In this way standard techniques developed for the analysis of individual genetic variation may be used to analyze gametic variation. An example is given for maternal gametic imprinting and equivalence is shown to a gametic model. The method may also be adopted for the analysis of species (like the honey bee) with one haploid sex.

In recent years community-based livestock breeding programs (CBBPs) have received some attention and have been considered as a new and more sustainable option to improve livestock production under smallholder conditions and in low-input systems. Most CBBPs are found with livestock keepers owning local breeds of small ruminants. The idea of CBBPs is that livestock keepers with a common interest in improving their genetic resources work together and jointly develop breeding strategies, which are based on their local rules and institutional settings. This bottom-up process ensures that the decision-making power remains with the livestock keepers. However, scientists play an important role as facilitators, moderators, and technical experts and can provide guidance and bring their know-how to the various steps in the design and implementation of a breeding program. Beside the numerous technical challenges, there are also various socio-cultural aspects that have to be addressed and discussed with the participants of the breeding program. Enough room for reflection and discussion on traditional norms and values and possible changes has to be provided. In some cases changes can maybe more easily proposed and initiated by scientists as they are outsiders of the communities. The important role of women in the different aspects of livestock management is indisputable, but their participation in decision-making processes not only in households but also at a breeders' association or at the community level is often neglected. Therefore, new forms of cooperation and modification of traditional roles of disadvantaged groups should be considered. Exclusion of women impoverishes the knowledge base, so that future adaption options might be overlooked. In addition, excluding women undermines the legitimacy of the institutions, thus threatening the whole management system. Inclusion of different viewpoints of concerned actors leads to more sustainable solutions and makes a production system more resilient.

The Baladi is a native Bos taurusbreed of the Mediterranean basin known for its hardiness, disease resistance, tolerance of poor care, meager diet and adverse climate conditions. In Israel, and probably in other Mediterranean countries, the Baladi breed is in danger of extinction due to the introduction of larger more productive European breeds. Domestication of cattle occurred independently in two or three sites: Southwest Asia (Bos taurus), Southeast Asia (Bos indicus), and possibly North Africa (Bos taurus). In this study, global admixture analysis of pure Baladi and 15 other cattle breeds around the world were used to investigate the ancestral components of the Baladi genome. The Baladi was revealed as a unique combination of the three main postulated ancestral cattle domestications, having each component in roughly equal proportions, and thus represents an enormous store of cattle genetic diversity. Local admixture analysis exposed regions characterized by positive deviation for the Indicine and African Taurine genome components of the Baladi genome and mostly negative selection against the Southwest Taurine component. Thus, these regions may harbor genomic elements increasing the Baladi local adaptation. The Baladi share similar global and local admixture profiles with three Turkish breeds. Thus, all four breeds may be considered in large part as independent replicates taken from the same Middle East ancestral mix. This brings enormous potential for high-resolution validated mapping of chromosomal regions contributing to adaptation. Thus, from both a practical and preserving biodiversity views, the Baladi is a prime candidate for conservation.