Upgrading breeding value estimation in beef cattle

This paper gives a summary of the possibility for applying genomic information for breeding value estimation in beef cattle breeding. This process is called genomic prediction and is now widely used in dairy cattle globally as well as in some beef and sheep populations. The advantage of genomic prediction is a more accurate estimate of the genetic merit of an individual at a young age thereby facilitating greater annual genetic gain, predominantly through shorter generation intervals. Genomic predictions are more advantageous for sex-linked (e.g., milk yield), low heritability (e.g., fertility) and difficult-to-measure (e.g., feed intake) traits. The larger the reference population, on average, the more accurate the genomic predictions; additionally, the closer genetically the reference population is to the candidate population, the greater the accuracy of genomic predictions. Research is continuing on strategies to generate accurate genomic predictions using a reference population consisting of multiple breeds (and crossbred). Retrospective analysis of real-life data where genomic predictions have been operation for several years clearly shows a benefit of this technology

Genotyping of four loci in Hungarian Yellow and broiler chickens

Traditional selection has led to remarkable differences in allele frequencies among various chicken breeds. Indigenous and broiler-type chicken populations were genotyped for polymorphisms in thyroid hormone responsive Spot14α, prolactin (PRL), IGF-binding protein 2 (IGFBP2), and somatostatin (SST) genes in order to determine potential utilisation type-associated allele frequencies. Significant (P < 0.05) differences were detected between Hungarian Yellow and broiler populations for Spot14α, PRL, and IGFBP2 allele frequencies, whereas the same SST allele (A) was fixed in both groups. In this study, the most significant associations (P < 0.05) were found between the IGFBP2 genotypes and the measured traits (body weight, carcass weight, breast muscle weight with or without skin, breast muscle weight as a percentage of carcass weight) in the broiler population. The results can be applied for the evaluation of polymorphism effects in the analysed populations; however, contradictory allele effects in different breeds and hybrids indicate the need for cautious marker utilisation in selection programmes

Beta-Casein Genotyping in Dairy Cow Herds in Gyor-Moson-Sopron County

The main objective of this study was to determine the beta-casein A1/A2 polymorphism status of animals in two Holstein Friesian dairy cow herds in Gyor-Moson-Sopron County, Hungary. The A1/A2 status of cattle is determined by the beta-casein gene on the sixth chromosome. The analysed single nucleotide polymorphism is non-synonymous; A1 and A2 variants of bovine beta-casein differ at position 67 of the amino acid chain: A1 variant codes for histidine and A2 codes for proline, which may affect the milk protein degradation process. The analysed polymorphism leads to key conformational changes in the secondary protein structure of beta-casein. Beta-casomorphin (known as BCM7) is released only from A1-type milk and cannot be completely degraded by enzymes during digestion. DNA isolation was performed from whole blood, and a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method with agarose gel electrophoresis was applied in order to determine individual genotypes. The results from the two dairy farms demonstrate that a high proportion of cows (86.08 and 90.74 %) carry the A2 gene variant without targeted selection. At farm „A”, beta-casein polymorphisms were determined in 599 cows and 148 heifers. The genotype distribution of the cows was 47.25 % heterozygous, 38.83 % homozygous A2, whereas 14.02 % of the cows carried the A1A1 genotype. In heifers, A2A2 was already present in a remarkably high frequency (91.89 %), whereas the prevalence of heterozygotes was 7.43 %, and A1A1 animals made up only 0.67 % of the analysed heifer population. In Hungary, a growing number of dairy farms are using verified A2 homozygous breeding bull semen. The introduction of homozygous A2 sperm on the farm „A” remarkably increased A2 frequency in the heifer population. In total, 324 cows were genotyped on farm „B”, where the A2A2 genotype was observed in 30.55 % of the animals. The second most common genotype was A1A2, with a genotype frequency of 60.19 %, whereas A1A1 homozygotes occurred with a 9.26 % frequency. The growing popularity of A2 milk due to potential health benefits is driving Hungarian stakeholders towards the targeted selection of dairy populations; animal genotyping is an evident approach to facilitate this transition

Gene Expression of Peroxisome Proliferator-Activated Receptor ? in Mangalica and Large White Pigs

The expression of peroxisome proliferator-activated receptor ? gene (PPAR?) – a major regulator of adipogenesis and intramuscular fat deposition in pigs – was analysed in different tissues of Blonde Mangalica (M) and Hungarian Large White (LW) by means of quantitative reverse transcription PCR. In total, 20 experimental animals were raised and fed under identical conditions, and transported to the abattoir at similar body weight (124.7±10.3 kg; p>0.05). In both breeds highest PPAR? expression was observed in backfat (p0.05). Elevated PPAR? expression was observed in M backfat compared to LW (

Yield Performance, Laying Behaviour Traits and Egg Quality of a Crossbred Laying Hen in Alternative Housing Systems

One aim of this study was to investigate a crossbred laying hen line (400 hens) in two alternative housing systems in two replicates between 20-72 weeks of age. One rearing system was deep litter (D) with artificial light. Hens from Group R were housed in a poultry house with windows on deep litter and access to a runway without artificial light. Birds were fed ad libitum with a concentrate layer feed (18.0 % protein, 11.6 MJ). The egg production was influenced by the housing system. Lower average egg weight was observed in Group R. The feed consumption was also lower here, but the FCR was better compared to D. Floor egg did not cause any problem in the examined systems. The shell strength decreased with age in both systems. However, the rate was higher in Group D. The albumen height and HU value were higher in Group R at the end of the experiment (72nd week of age). Some differences were found in the fatty acid profile between the two housing systems. Another goal of the study was to observe the behaviour patterns of animals kept under different conditions. Behavioural traits were monitored for 100 hens in total on the two farms that applied different housing technologies (50-50 birds with or without outdoor access). Birds with outdoor access showed 0.23±0.81 aggression-related traits per hour, whereas chickens without outdoor access produced 0.15±0.76 of the same traits (p>0.05). Hens with outdoor access showed 2.30±4.65 activity-related traits, whereas, for hens without outdoor access, 0.72±1.83 observations were recorded per hour (p0.05) in the two groups. In conclusion, the housing system has a complex effect on the assessed crossbred laying hen line

A specific selection programme is required in the autochthonous Cikta Sheep which is endangered by own frequent ARQ prion haplotype?

The authors study the current status of Hungarian Cikta Sheep based on genetic background of scrapie resistance. The aim of this investigation was to estimate the relative frequency of prion haplotypes, -genotypes, and risk categories as well as to reveal the efficiency of scrapie eradication program achieved over the last decade. The authors confirmed based on larger sample size the previous knowledge, that the resistance against scrapie of Cikta breed is considered as low, and the classification of this breed according to risk category has not been improved. However, the frequent genotype ARQ and risk category 3 can also be considered for breed specificity. The careful use of these genotypes is permitted and will contribute to the maintenance of breed diversity according to other aspects