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The objective of this experiment was to assess the reproductive and productive performance of Nguni cattle distributed among 11 farms in four regions of South Africa. Only data of registered Appendix A to Stud Proper Nguni animals from the Agricultural Research Council of South Africa’s database were used. Data were collected from 2061 dams and 3285 calves between 1990 and 2009. Overall means for age at first calving (AFC) and calving intervals (CI) were 33.79 ± 4.90 months and 400.29 ± 78.70 days, respectively. Dry season-born heifers had lower AFC than wet season-born heifers. Dry seasons 4 and wet seasons 1 had lower CI than seasons 2 and 3, indicating that conceptions take place between December and May. Average growth weights of calves were 24.87 ± 3.13, 151.91 ± 21.09, 169.25 ± 23.68 and 237.96 ± 27.34 kg at birth (BW), weaning (WW), 12 months (YW) and 18 months of age, respectively. BW was higher in dry seasons 4 and wet seasons 1; WW and YW were higher in dry than in wet seasons. This is the first study demonstrating that performance of Nguni cattle is influenced by ecological regions of the dam’s origin, year-season of birth/calving, breeder’s management, parity and herdbook status, confirming that environment-genotype interactions influence the performance of Nguni cattle in southern Africa. This stimulated a follow-up study on the use of geographic information systems to specifically identify factors influencing the reproductive and productive performance of Nguni cattle in southern Africa.

The goal of this research was to document the influence of Line 1 (L1) Hereford cattle, developed by the USDA at its research facility in Miles City, MT, on the U.S. Hereford population. The L1 Hereford population originated in 1934 and has been thereafter maintained as a closed herd at that location. Dissemination of germplasm began in 1948. Pedigree data for approximately 14 million cattle recorded by the American Hereford Association (AHA) were used. A preliminary experiment was conducted to establish sample size necessary to estimate the pedigree relationship between L1 and the recorded Hereford population. Five random samples of 100, 400, 500, and 3,000 calves were drawn from the sets of calves born in 1980, 1990, and 2000. Sampled calves were pseudo mated to L1 sires from the decades 1968 to 1978, 1978 to 1988, and 1988 to 1998, respectively. Inbreeding coefficients were calculated for the resulting "offspring" and the relationship of each sampled animal to L1 was taken to be twice the maximum inbreeding coefficient for the set of L1 sires used in the pseudo matings. Based on the results of this experiment, it was decided that a sample size of 400 animals per replicate was sufficient to estimate the relationship between L1 and the general Hereford population recorded by the AHA. In a second experiment, 5 sets of 400 animals were drawn from the AHA herdbook representing each year from 1980 to 2008 and pseudo mated to L1 sires and their relationship to L1 calculated as described above. Over the period, the number of animals recorded by the AHA that were related to L1 increased by 1.69 ± 0.07% per year. The L1 Hereford population was ancestral to 79% of Hereford cattle recorded in 2006 through 2008. The greatest concentration of animals related to L1 was in the Great Plains and eastern Corn Belt of the United States, but animals related to L1 were found in 48 states. In a third experiment, 240 L1 Hereford cattle and 311 sires representative of the Hereford breed in the United States were genotyped using the Illumina BovineSNP50 BeadChip. Resulting genotypes were used to assess the probability that the animals sampled from the U.S. population were members of L1. The average probability of membership in L1 was 0.20 and the regression of genomic probability of membership on pedigree relationship was 1.73 ± 0.11 (r = 0.65). These results document the far-reaching and profound impact of a long-term research program.

The objective of this study was to assess the reproductive performance of two Nguni ecotypes (Nguni and Landim) raised in a subtropical environment to enhance strategies for livestock development and restocking programmes within the southern African region. Reproduction data collected between 1996 and 2009 from 365 cows of the Landim and Nguni ecotypes were analysed. From the results, ecotype, place of birth, year and season of birth/calving had significant effects on age at first calving (AFC) and calving interval (CI). Overall means for AFC and CI were 1,071 ± 166 days and 432 ± 85 days, respectively, while average calving rate was 88.0 ± 4.7%. Heifers born in the dry season had lower AFC than heifers born in the wet season. Heifers born at Impaputo Breeding Center were the youngest at first calving, followed by the South African born ones. Heifers of the Landim ecotype also calved younger than heifers of the Nguni ecotype. CI was shorter in wet seasons (main breeding seasons) than in dry seasons. Interaction between ecotype and year-season (p < 0.005) showed that, in wet and dry seasons, Nguni cows had shorter CI than the Landim. This study demonstrates for the first time a possible genotype-by-environment interaction between Nguni ecotypes. This might aid future cattle development and restocking programmes in southern Africa taking into consideration the adaptation of indigenous genotypes and climate change.

Variance components and genetic parameters for greasy fleece weights of Muzaffarnagari sheep maintained at the Central Institute for Research on Goats, Makhdoom, Mathura, India, over a period of 29 years (1976 to 2004) were estimated by restricted maximum likelihood (REML), fitting six animal models including various combinations of maternal effects. Data on body weights at 6 (W6) and 12 months (W12) of age were also included in the study. Records of 2807 lambs descended from 160 rams and 1202 ewes were used for the study. Direct heritability estimates for fleece weight at 6 (FW6) and 12 months of age (FW12), and total fleece weights up to 1 year of age (TFW) were 0.14, 0.16 and 0.25, respectively. Maternal genetic and permanent environmental effects did not significantly influence any of the traits under study. Genetic correlations among fleece weights and body weights were obtained from multivariate analyses. Direct genetic correlations of FW6 with W6 and W12 were relatively large, ranging from 0.61 to 0.67, but only moderate genetic correlations existed between FW12 and W6 (0.39) and between FW12 and W12 (0.49). The genetic correlation between FW6 and FW12 was very high (0.95), but the corresponding phenotypic correlation was much lower (0.28). Heritability estimates for all traits were at least 0.15, indicating that there is potential for their improvement by selection. The moderate to high positive genetic correlations between fleece weights and body weights at 6 and 12 months of age suggest that some of the genetic factors that influence animal growth also influence wool growth. Thus selection to improve the body weights or fleece weights at 6 months of age will also result in genetic improvement of fleece weights at subsequent stages of growth.

Seven indigenous chicken populations were identified and characterized from four administrative zones in northwest Ethiopia. A total of three hundred chickens were characterized under field conditions for qualitative and quantitative traits following standard chicken descriptors. Large phenotypic variability among chicken populations was observed for plumage color. About 25.49, 22.3, and 16.4 % of the chickens have white, grayish and red plumage colors, respectively. The rest showed a considerable heterogeneity like black, multicolor, black with white tips, red brownish and white with red striped plumage colors. The following characteristics were also displayed: plain head shape (51.18%), yellow shank color (64.42%) and pea comb (50.72%). About 97.52% of the chickens did not have feathers on their legs. Variations were also observed on quantitative characters such as shank length, egg size and body weight and other reproductive traits characterized on intensive management system.

Surveys using both purposive and random sampling methods was carried out in four zones of north-west Ethiopia to describe the village-based poultry production systems and constraints in order to design future improvement and conservation strategies. The majority of the respondents were female (74.16%). This indicated that most of the time the women, whether in male-headed or female-headed households, are responsible for chicken rearing while the men are responsible for crop cultivation and other off-farm activities. About 99% of the respondents gave supplementary feeds to their chickens. Almost all farmers provided night shelter for their chickens, in part of the kitchen (1.36%), in the main house (39.07%), in hand-woven baskets (7.29%), in bamboo cages (1.51%) or in a separate shed purpose-made for chickens (50.77%). The major causes of death of chickens during the study were seasonal outbreaks of Newcastle disease (locally known as fengele) and predation. It is important to collect and conserve local poultry breeds before they are fully replaced by the so-called improved breeds. As most of the poultry production is managed by women, focusing on training and education of women will enable not only the improvement of poultry production but also family planning and the overall living standards of the family and the community.

Genetic parameters were estimated for birth-, 42-day, and 100-day (weaning) weight in the Dorper flock of the Glen Agricultural Institute in South Africa. Direct heritability estimates of 0.11, 0.28 and 0.20 and maternal heritability estimates of 0.10, 0.10 and 0.10 were obtained for body weights at birth, 42 and 100 days, respectively. The corresponding genetic correlation estimates between direct and maternal effects were 0.35, -0.63 and -0.58, respectively. Both direct and maternal genetic correlation estimates among the traits were of moderate to high magnitude and positive. It is concluded that the traits can be improved by selection with no serious antagonisms among traits studied.