O. Vangen

Reduced genetic structure of north Ethiopian cattle revealed by Y-chromosome analysis.

Ethiopia is considered to be a putative migratory corridor for both Near-East Bos taurine and Arabian and Indian B. indicus cattle into East Africa. African pastoralism, which is associated with adaptation to specific habitats and farming systems, has contributed to the composite constitution of Ethiopian cattle. We analyse, for the first time, five Y-chromosome microsatellite markers from seven north Ethiopian cattle populations, using a European Holstein-Friesian population as a reference, to assess the paternal gene pool and to explore the mechanisms behind the genetic structure. Our results reveal that the indicine alleles predominate in the present populations, with only one animal in the Arado carrying the taurine alleles. The north Ethiopian cattle populations with one exception (Abergelle) are characterized by a general low Y-chromosome haplotype diversity, as well as by a reduced interpopulation variance (ΦST=4.0%), which can be a result of strong male-mediated selective sweeps. Population structure revealed by multidimensional-scaling analysis differentiates two populations (Arado and Abergelle) from the rest. Analysis of molecular variance does not lend support to the traditional classification for the populations, which is mainly based on physical characteristics. A network analysis indicates two closely related founding haplotypes accounting for a large proportion (50.0% in Abergelle and 85.0–94.7% in others) of north Ethiopian cattle Y-chromosomes. Our findings point to a common, but limited, paternal origin of the north Ethiopian cattle populations and strong male-mediated gene flow among them. The findings also provide insight into the historical immigration of cattle into East Africa.

Differences in grazing behaviour between a high and a moderate yielding Norwegian dairy cattle breed grazing semi-natural mountain grasslands

Abstract The grazing behaviour of cows from two mixed herds grazing semi-natural mountain grasslands was studied for two weeks each summer during three years. The two breeds included in the study were the high yielding, modern dairy cattle breed Norwegian Red (NR) and the moderate yielding, old dairy cattle breed Blacksided Trønder and Nordland Cattle (STN). Grazing behaviour included general activities such as walking, standing, lying and playing, and grazing activities such as grazing, drinking and ruminating. During the daily grazing period the cows’ grazing behaviour were recorded at fixed intervals of 10 or 15 min. Breed differences were found in three of the recorded traits. The NR cows showed a higher frequency of ‘standing’ than the STN cows (p<0.01), and the STN cows showed higher frequencies of ‘walking’ (p<0.05) and ‘playing’ (p<0.01) than the NR cows. The time spent on grazing showed no difference between the breeds. The number of observations in the present study was somewhat limited as these types of studies are very resource demanding. Longer recording periods, more animals and farms would have been preferable. However, the breed differences expressed are in line with the expectations with regard to playing, standing and walking, while grazing activity did not follow the hypothesis made.

Dietary Energy and Protein for Growing Pigs: 1. Performance and Carcass Composition

Abstract In a joint Nordic project, four experiments with a total of 880 growing pigs following the same outline were conducted in Denmark, Norway, Finland and Sweden. In three of these experiments the animals were fed individually. Five dietary treatments were investigated with respect to effects on performance, carcass composition and leg condition by entire or partial dissection. The treatments were: (1) restricted standard feeding as a reference in all experiments; (2) ad libitum feeding with protein (amino acid) concentrations according to recommended allowances (RA); (3) as in (2) but RA increased by 10% (RA + 10%); (4) as in (2) but RA lowered by 10% (RA - 10%), or (5) the most common restricted feeding scale recommended in the individual countries, thus being different from experiment to experiment. Compared with the restricted standard feeding, for which daily feed intake and daily weight gain in the weight range 23–100 kg averaged 2.07 kg and 750 g, respectively (rel. value 100), the correspondi...

Genetic diversity and admixture of indigenous cattle from North Ethiopia: implications of historical introgressions in the gateway region to Africa

Microsatellite variation was surveyed to determine the genetic diversity, population structure and admixture of seven North Ethiopian cattle breeds by combining multiple microsatellite data sets of Indian and West African zebu, and European, African and Near-Eastern taurine in genetic analyses. Based on allelic distribution, we identified four diagnostic alleles (HEL1-123 bp, CSSM66-201 bp, BM2113-150 bp and ILSTS6-285 bp) specific to the Near-Eastern taurine. Results of genetic relationship and population structure analyses confirmed the previously established marked genetic distinction between taurine and zebu, and indicated further divergence among the bio-geographical groupings of breeds such as North Ethiopian, Indian and West African zebu, and African, European and Near-Eastern taurine. Using the diagnostic alleles for bio-geographical groupings and a Bayesian method for population structure inference, we estimated the genetic influences of major historical introgressions in North Ethiopian cattle. The breeds have been heavily (>90%) influenced by zebu, followed by African, European and the Near-Eastern taurine. Overall, North Ethiopian cattle show a high level of within-population genetic variation (e.g. observed heterozygosity = 0.659-0.687), which is in the upper range of that reported for domestic cattle and indicates their potential for future breeding applications, even in a global context. Rather low but significant population differentiation (F(ST) = 1.1%, P < 0.05) was recorded as a result of multiple introgression events and strong genetic exchanges among the North Ethiopian breeds.

Dietary Energy and Protein for Growing Pigs: 2. Protein and Fat Accretion and Organ Weights of Animals Slaughtered at 20, 50, 80 and 110 kg Live Weight

Abstract This investigation was performed to study the effects of restricted versus ad libitum feeding on carcass composition, on protein and fat accretion and on body development and organ weights. The carcass composition was evaluated on 168 pigs by serial slaughter at 20, 50, 80 and 110 kg LW. The chemical composition was examined in only 62 of these animals. The carcasses were partitioned into four cuts and dissected into lean meat, fatty tissue, rind and bones. Ad libitum feeding resulted in daily weight gain exceeding restricted feeding in the three weight ranges by 42%, 17% and 7% and feed conversion ratios by 3%, 15% and 9%, respectively. Castrated males exceeded daily weight gains of females by 6%. At 20 kg the carcass moisture content was 65% for both sexes, which on average over feed regimens at 110 kg decreased to 56% and 52% for females and castrated males, respectively. Correspondingly, the carcass crude fat (CF) content increased from 13% to 24% and 30%, respectively. At 110 kg LW on restri...

Carcass and meat quality characteristics of young bulls of Norwegian cattle and crossbreds with Angus, Hereford and Charolais

Crossbreeding effects on beef production characteristics, growth, carcass and meat quality traits were registered on a total of 162 purebred Norwegian (NRF) dual‐purpose and crossbred bulls obtained from mating (AI) NRF dams with NRF, Aberdeen Angus, Hereford and Charolais sires. The offspring were reared in commercial farms until slaughter. Data were analysed by mixed models and adjusted to either constant carcass weight (305 kg), slaughter age (19.5 mos.) or carcass fat level (6% fat) end points. Improvements in beef production traits obtained by crossbreeding were highly dependent on the choice of sire beef breed. NRF × Charolais crossbreds had the highest daily carcass gain and carcass quality (fleshiness grading) at all end points. Crossbreeding with Aberdeen Angus and Hereford gave no growth advantages, an intermediate increase in carcass fleshiness grading and an increase in weight constant carcass fat level compared to purebred NRF. The small, significant breed differences observed for colour, fla...

Genetic conditions of joint Nordic genetic evaluations of lifetime competition performance in warmblood sport horses

Breeding programmes for warmblood sport horses are similar in the Nordic countries Sweden, Denmark, Finland and Norway, and stallions of same origin are used. The aim was to investigate whether a joint Nordic genetic evaluation based on lifetime competition performance is feasible and beneficial for breeding competitive sport horses in the Nordic countries. Results for almost 45,000 horses in show jumping and 30,000 horses in dressage were available. The larger populations in Sweden and Denmark contributed with 85% of the results. Heritabilities and genetic correlations between performances in the different countries were estimated, and comparisons of accuracies of estimated breeding values (EBVs) and number of stallions with EBVs based on national or joint data were studied. The heritabilities ranged between 0.25 and 0.42 for show jumping and between 0.14 and 0.55 for dressage. The genetic correlations between competition performances in the Nordic countries were estimated to 0.63-1.00. EBVs based on joint data increased accuracies for EBVs for stallions by 38-81% and increased the number of available stallions with EBVs by 40-288%, compared to EBVs based on national data only. A joint Nordic genetic evaluation for sport horses is recommended.

Improvement in the national genetic evaluation of warmblood riding horses by including information from related studbooks

Abstract Young horse performance test data from two warmblood riding horse populations, Norwegian warmblood (NWB) and Swedish warmblood (SWB), were analysed to examine whether including information from a related studbook would increase the accuracy of the genetic evaluations within a population. Ten conformation and performance traits from 31,588 horses, 774 NWB and 30,814 SWB were analysed separately and jointly using single trait animal models. Heritabilities were moderate to high, and varied from 0.15 (conformation, joint data) to 0.74 (jumping technique, NWB data). The genetic similarity (GS) between populations was 31%, with the SWB, as expected given the size of the populations, contributing most to the GS (98%). Genetic correlations between the same traits in the two populations were 0.43–0.90 but with large standard errors (0.2–0.3). Including information from the other population increased the average accuracy of estimated breeding values for common stallions, on average 4% for SWB and 110% for NWB.

The effect of including genomic relationships in the estimation of genetic parameters of functional traits in pigs

The term functionality in animal breeding is used for traits that increase the efficiency of production by lowering the input cost, such as animal health and leg weakness related to longevity. The main objective of the study was to investigate the impact of genomic information, in a multivariate variance component analysis, on some of these traits. In addition, the effect of the inclusion was studied by testing the models prediction ability based on best linear unbiased estimates for fixed and random effects. The material in this study consists of phenotypes from 76,683 animals, of which 4933 animals are genotyped. The heritabilities for front leg conformation, stayability, osteochondrosis and arched back, estimated using the traditional pedigree, were found to be between 0.12 and 0.29. When using the combined genomic and pedigree relationship matrix, the heritabilities were between 0.14 and 0.36. The results show that the combined relationship matrix can be used for the estimation of (co)variance components, and that the predictive ability of the model in this study marginally increases with the inclusion of genomic information.

Genetic analyses of hunting traits in leashed and non-leashed test systems in Norwegian Elkhound

ABSTRACT Norwegian Elkhound Grey is used for both leashed and non-leashed tracking. This study provides influence of fixed effects and estimates of genetic parameters of traits related to both types of tracks. In total, 5393 records from 1991 animals tested in the years 1995–2014 on lashed performance (5 traits), and 5405 records from 2070 animals tested in the years 2005–2014 on non-leashed performance (10 traits) were included in the dataset. The pedigree file contained 8623 animals. Heritabilities were generally low for the non-leashed traits and a bit higher for the leashed traits. Genetic correlations within trait group were very highly positive for the leashed dog traits, but variable among some traits in the non-leashed group. Genetic correlations between performance traits in the two groups were generally negative and unfavourable. Genetic trends were generally positive for the time periods.