Estimation of genetic parameters and genotype effects for crossing constructions of Hungarian Pigs57-60Views:128
Authors estimated the genetic parameters and genotype effects of average daily gain (ADG), age (AGE) and lean meat percentage (LMP) using the field test data of Pietrain (Pi), Duroc (Du), Hampshire (Ha) pigs and their crosses. Data was collected by the Agricultural Agency of Administration between 1998 and 2010 originating from 68 herds. Datasets of the different crossing combinations (Pi, Du, Pi × Du; Pi, Ha Pi × Ha) were evaluated separately using bivariate animal models. The estimated heritabilities were moderately low: 0.24–0.29, 0.22–0.26 and 0.18–0.19 for average daily gain (ADG), age (AGE) and lean meat percentage (LMP), respectively. The estimated genetic correlation coefficients were negligible: -0.07–0.01 (ADG-LMP), -0.01–0.04 (AGE-LMP). The Pi × Ha and Pi × Du crosses showed 6.76% and 4.96%; 6.74% and 4,17% and 0.08% and 0.44% heterosis for ADG, AGE and LMP, respectively. Among the environmental factors the herd effects were substantial: 41.17%, 53.67% and 14.16% for AGD, AGE and LMP, respectively. The smallest environmental influences were found for LMP.
Development of the reproductive tract of immature gilts165-166Views:57
Mechanisms of regulation of litter size in pigs are complex and depend on many factors, including genetic regulation and also physiological and anatomical development of the reproductive tract in gilts. Improvement of growth rate in present breed pigs raises the question as to whether, with the development of the reproductive tract, sexual maturity would also be attained.
The aim of the study was to assess the morphometric traits of reproductive tracts taken from gilts slaughtered at 100 kg body weight, i. e., just when they may become actively sexual mature.
This study was concluded on 80 prepubertal gilts of the Polish Landrace (PL) breed tested at the Pig Program Testing Station. The animals were kept in individual pens with control feeding and standard management. They were slaughtered after attaining 100 kg body weight. Immediately after slaughter, the reproductive tract was removed and carefully assessed. The morphometric estimation of the reproductive tract involved the
measurement of uterus weight with ligament, vagina-cervix length, uterine horns and oviducts length, ovaries weight, height and width. Uterus volume capacity was also determined, based on volumetric method of Kwaśnicki’s (1951) with own modification.
All pigs were divided into three groups in respect to age at slaughter: A – below 160 days (n=38), B – from 160 to 180 days (n=28) and C – above 180 days of age (n=14). The results were elaborated statistically computing the arithmetic means (x) for every traits and standard deviations (s). One-way analysis of variance ANOVA was performed. The significance of differences between age groups was estimated using Duncan’s test.
Calculations were performed with STATISTICA 8PL Software.
Obtained results are presented in the tables below. The most pronounced differences in the development of the reproductive tract are dependent on the age of gilts concerning only the uterus weight (P≤0.01) and uterus vagina-cervix length (P≤0.05). Gilts at age 160-180 days attained the full stage of reproductive tract development. Differences between the compared age groups of gilts dealing with the other morphometric traits
and ovary characteristics were statistically not significant.
Comparison of major population parameters of Brown hare (Lepus europaeus, Pallas 1758) in two hunting fields of the Great Hungarian Plain69-74Views:131
Hungarian stock of game is not only part of our national treasure but also one of our domestic products and economic income. Not indifferent therefore the number and the state of health of our wildlife. Population decline of the Brown hare (Lepus europaeus, Pallas 1758) (one of our most important small game in Hungary) takes a long time. Demographic parameters of Brown hare was examined, particularly the factors affecting the decline of the species in Hungary. We took samples from typical habitats where the Brown hare could be found in relatively high density in our country. The article reports data of reproductive characteristics, diseases, parasites of Brown hare and other factors such as climatic and anthropogenic which could influence of the population dynamics. We mention sample collection and processing methods eg: population size estimates, examination of reproductive organs, the sex ratio and the age structure as well as the individual condition based on data of domestic and foreign authors and our partial results.
Upgrading breeding value estimation in beef cattle451-458Views:177
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.
Evaluation of Hungarian Sporthorse mare performance tests83-87Views:76
Results of the Hungarian Sporthorse mare performance tests were evaluated. Data from the period of 1993-2009 were used, covering
scores of 618 3-year-old and 310 4-year-old mares, 109 of them were tested at both ages. Seventeen traits were scored on the tests, which
covered ten conformational, three free jumping performance and four movement analyses traits, respectively. Breeding value estimation was
based on BLUP animal model. Test year, age and owner were included in the model as fixed effects. Variance components were estimated
with VCE-6 software package. Heritabilities ranged from 0.32 (frame) to 0.50 (saddle region) for conformation traits, from 0.39 (jumping
style) to 0.49 (jumping ability and jumping skill) for free jumping traits and from 0.20 (walk) to 0.48 (canter) for movement analysis traits.
Breeding value indexes were constructed for each trait group. Conformation index was computed based on the weighted scores of the
breeding values of conformational traits. The conformational score scales were used as weightings. Free jumping and movement indexes
contain the proper breeding values with equal weights. A total index was also constructed using conformation index, two times the free
jumping index and two times the movement index. Each breeding values and breeding value indexes were presented with the mean 100 and
standard deviation of 20 for the easier understanding.