Influence of environmental and geographical factor on the heavy metal content in the lungs of Hereford cattle

The problem of food contamination by heavy metals due to their accumulation in biosystems as a result of anthropogenic influences has been studied. The results of cadmium, lead, iron and manganese in cattle from the Novosibirsk Region and the Altai Territory are presented. The purpose of the study was to assess the impact of the ecological and geographical factor on the heavy metal content in the lungs of Hereford bulls. Lung samples were taken from 31 clinically healthy Hereford bulls aged 16-18 months. Sample preparation was carried out in accordance with GOST 26929-94 and 30178-96. The chemical composition of the samples was determined by atomic absorption spectrometry with flame and electrothermal atomization. The median values of the content of cadmium, lead, iron and manganese in the lungs of bull-calf were in the range of 0,01-0,12; 0,07-0,11; 70,9-89,1 and 0,3-0,4 mg/kg. The phenotypic variability of the level of iron and manganese was relatively low, while that of lead and cadmium was high. The dispersions of lead and cadmium levels in the animal groups studied were homogeneous, manganese and iron variants were heterogeneous. The influence of the ecological and geographical factor is characteristic only for cadmium levels. For manganese, iron, lead and cadmium the calculated reference ranges are: 0-1.12; 0-148.1 and 0-0.170 mg/kg respectively. They can serve as a guideline for Hereford cattle bred in the territories of Krasnozersky, Novosibirsky and Maslyaninsky districts of the Novosibirsk region and the Tselinny district of the Altai Territory.

A KRT71 Loss-of-Function Variant Results in Inner Root Sheath Dysplasia and Recessive Congenital Hypotrichosis of Hereford Cattle

Genodermatoses, such as heritable skin disorders, mostly represent Mendelian conditions. Congenital hypotrichosis (HY) characterize a condition of being born with less hair than normal. The purpose of this study was to characterize the clinicopathological phenotype of a breed-specific non-syndromic form of HY in Hereford cattle and to identify the causative genetic variant for this recessive disorder. Affected calves showed a very short, fine, wooly, kinky and curly coat over all parts of the body, with a major expression in the ears, the inner part of the limbs, and in the thoracic-abdominal region. Histopathology showed a severely altered morphology of the inner root sheath (IRS) of the hair follicle with abnormal Huxley and Henle’s layers and severely dysplastic hair shafts. A genome-wide association study revealed an association signal on chromosome 5. Homozygosity mapping in a subset of cases refined the HY locus to a 690 kb critical interval encompassing a cluster of type II keratin encoding genes. Protein-coding exons of six positional candidate genes with known hair or hair follicle function were re-sequenced. This revealed a protein-changing variant in the KRT71 gene that encodes a type II keratin specifically expressed in the IRS of the hair follicle (c.281delTGTGCCCA; p.Met94AsnfsX14). Besides obvious phenocopies, a perfect concordance between the presence of this most likely pathogenic loss-of-function variant located in the head domain of KRT71 and the HY phenotype was found. This recessive KRT71-related form of hypotrichosis provides a novel large animal model for similar human conditions. The results have been incorporated in the Online Mendelian Inheritance in Animals (OMIA) database (OMIA 002114-9913).

17 A De novo Recessive Mutation Causative of Mandibulofacial Dysostosis in Hereford Cattle

In spring 2020, six Hereford calves presented with congenital craniofacial abnormalities attributed to a condition we termed mandibulofacial dysostosis (MD). Pedigree analysis revealed a single common ancestor shared by the sire and dam of each affected calf. We hypothesized that MD in Hereford cattle is attributed to a de novo mutation with an autosomal recessive mode of inheritance. To avoid production of affected calves, the objective of this study was to identify the cause of MD. Whole-genome sequencing (WGS) of 20 animals (3 affected, 7 obligate carriers, 10 related) yielded 143 variants matching the hypothesized mode of inheritance. Genotyping of 2 additional affected calves, 760 Herefords, and evaluation of WGS data from over 2,500 other individuals led to the discovery of a missense mutation (Chr26 g. 14404993 T >C) in CYP26C1 associated with MD. The amino acid change due to the CYP26C1 variant (p. L188P) is located in an α helix of the protein; modeling suggests the substitution breaks the helix. The mutation is predicted to be deleterious (SIFT = 0) and is otherwise conserved across species. In our data, all heterozygotes had at least one pedigree tie to the suspect founder. CYP26C1 plays a vital role in tissue-specific regulation of retinoic acid (RA) during embryonic development. Dysregulation of RA can result in teratogenesis by altering the endothelin-1 signaling pathway affecting the expression of Dlx genes, critical to mandibulofacial development. Further, multiple human conditions with similar pathologic characteristics are attributed to dysfunction of this gene and/or retinoic acid signaling. We conclude that this recessive missense mutation in CYP26C1 impacts the catalytic activity of the encoded enzyme, leading to excess RA and resulting in the MD phenotype. Breeders can now genotype their animals to identify carriers. These data also contribute to expanding the understanding of craniofacial development across species.

The Molecular Bases Study of the Inherited Diseases for the Health Maintenance of the Beef Cattle

The article highlighted the problem of meat cattle genetic defects. The aim was the development of DNA tests for some genetic defects diagnostics, the determination of the animal carriers and their frequencies tracking in time. The 1490 DNA samples from the Aberdeen Angus (n = 701), Hereford (n = 385), Simmental (n = 286) and Belgian Blue (n = 118) cattle have been genotyped on the genetic defects by newly created and earlier developed DNA tests based on AS-PCR and PCR-RFLP methods. The Aberdeen Angus cattle genotyping has revealed 2.38 ± 0.31% AMC-cows and 1.67 ± 0.19 % AMC-bulls, 0.65 ± 0.07% DDC-cows and 0.90 ± 0.10% DDC-bulls. The single animals among the Hereford cattle were carriers of MSUD and CWH (on 0.27 ± 0.05%), ICM and HY (on 0.16 ± 0.03%). The Simmental cattle were free from OS. All Belgian Blue livestock were M1- and 0.84%-CMD1-carriers. The different ages Aberdeen Angus cattle genotyping has shown the tendency of the AMC- and DDC frequencies to increase in the later generations. The statistically significant increase of DDC of 1.17% in the cows’ population born in 2019 compared to those born in 2015 allows concluding the further development of the DNA analysis-based measures preventing the manifestation of the genetic anomalies in meat cattle herds is necessary.

REARING AND BREEDING OF HEREFORD CATTLE ON A PEASANT (FARM) ENTERPRISE

Авторами разработан инновационный проект по выращиванию и разведению крупного рогатого скота мясного направления на базе К(Ф)Х Михеевой С. И. и подготовлена конкурсная документация по отбору участников мероприятий по поддержке начинающих фермеров и развитию семейных животноводческих ферм крестьянских (фермерских) хозяйств государственной программы Пензенской области «Развитие агропромышленного комплекса Пензенской области на 2014-2022 годы». На основе результатов проведенного исследования разработана модель развития мясного скотоводства на базе крестьянского (фермерского) хозяйства. Данная модель предусматривает выращивание, доращивание и откорм крупного рогатого скота породы Герефорд. Преимуществами данной породы являются устойчивость и выносливость, простота в разведении, способность передавать положительные качества по наследству, высокие качества мяса. С учетом производственных показателей выращивания скота герефордской породы авторами определены финансовые показатели и экономическая эффективность производства говядины. Чистая прибыль в пятый год проекта составит 2213 тыс. руб., рентабельность затрат и продаж 123 и 55 % соответственно. Организация бизнеса с учетом технологических особенностей отрасли позволит К(Ф)Х Михеевой С. И. получать уровень рентабельности гораздо выше, чем в промышленности, а устойчивый спрос на мясо и мясопродукты гарантирует ее сбыт. The authors developed an innovative project for raising and breeding beef cattle on the basis of the peasant farm enterprise of Mikheeva S. I. and prepared competitive documentation for the selection of participants in measures to support beginning farmers and the development of family livestock farms of peasant farm enterprises under the Penza Region state programme "Development of the Agricultural Sector of the Penza Region in 2014-2022". Based on the results of the study, a model of beef cattle breeding development on the basis of a peasant (farm) enterprise was developed. This model provides for breeding, rearing and fattening of cattle of the Hereford breed. The advantages of this breed are stability and endurance, simplicity in breeding, ability to transfer positive qualities by inheritance, high quality of meat. Taking into account the production indicators of the Hereford cattle breeding, the authors determined the financial indicators and economic efficiency of beef production. Net profit in the fifth year of the project will be 2213 thousand rubles, profitability of costs and sales will be 123 and 55% respectively. Organization of business taking into account technological features of the industry will allow the P(F)E of Mikheeva S. I. to get a level of profitability much higher than in the industry, and stable demand for meat and meat products guarantees its sales.

HAEMATOLOGICAL PARAMETERS OF STEERS AFTER VASECTOMY

The Kazakh white-headed breed is a breed of beef cattle from Kazakhstan and Russia. The breed was developed between 1930 and 1950 on state farms in the Kazakh republic and the Lower Volga by crossing Hereford cattle with local Kazakh and Kalmyk stock. The breed resembles the Hereford in colour and conformation while incorporating the hardiness of the local breeds. The article shows the results of a study of blood parameters of Kazakh white-headed breed bulls after vasectomy. For this purpose two groups of 20 similar males of 12-14 months of age. The males of the experimental group underwent vasectomy in the farm «Aislu», by «torzing» the tail of the appendage. At 14-16 months of age blood samples were taken from both groups. Erythrocytes and haemoglobin, alkaline phosphatase, total protein, albumin, β and γ globulin were higher in vasectomized males. Data of leucocytes, calcium, phosphorus, reserve alkalinity, α- globulins were similar. Vasoectomy had little effect on serum lysozyme activity and on neutrophil phagocytic activity and phagocytic index. The bactericidal activity of serum of operated males was higher.

Economically useful traits of cows Australian breeding in the Amur region

Recently, a signifi cant number of livestock of specialized beef breeds is imported from abroad particularly from Australia. So the study of the adaptive ability and eff ectiveness of the use of Australian cattle of Hereford breed in the Amur region is relevant. The purpose of the work was to study the growth, development and reproductive capacity of Hereford cattle in the Amur region. Experimental studies have been carried out in the collective farm “Tomichevsky” in the Belogorsky district in the Amur region for four years. The reproductive ability of imported Hereford cows of Australian selection, as well as indicators of calving easy, live weight and height in the rump have been examined in the article. The assessment of similar indicators of progeny obtained from imported cows-dams and dams of local selection have been given. It has been found that the cows of the Australian breeding had a large live weight and were taller than the cows of Hereford breed the same age as the cows of Amur breeding. Fewer off spring were obtained from imported cows, a high percentage of dead calves were born, long open day’s period and calving interval, and a low coeffi cient of reproductive ability have been revealed. When analyzing the results of the study of the adaptive ability of Hereford cows obtained from imported Australian Hereford cows and Hereford cows of the Amur breeding, it has been found that all calving were successful in the cows, and no cases of dead calves were born. Indicators of reproductive ability were within the normal range, but were more optimal in the progeny of Australian breeding. The results obtained on base of researches we can conclude that the progeny of Australian Herefords have higher adaptive abilities in comparison with similar indicators of their mothers.

SELECTION IN HEREFORD CATTLE I. SELECTION INTENSITY, GENERATION INTERVAL AND INDEXES IN RETROSPECT

Selection intensity and generation interval were evaluated in a Hereford cattle herd of 14 inbred lines and 14 linecross groups corresponding to the lines of inbred sire at the San Juan Basin Research Centre, Hesperus, Colorado. Selection indexes practised were calculated in retrospect. The records analysed were weaning weight and postweaning traits in males and females collected from 1946 through 1973. Analyses were performed by line for the inbreds and pooled analyses for the inbred and linecross populations. From records of 1,239 calves weaned, age of sire averaged 3.75 years compared with 4.52 years for age of dam, showing faster generation turnover for sires than for dams. Generation interval determined 98 actual age of midparent was 4.13 years.Selection applied, evaluated as annual selection differentials within inbred lines and then pooled over all lines, averaged .55 standard deviations per generation for sires for weaning weight. Selection of females was much less. Midparent selection differential amounted to .33 standard deviations per generation. Pooled standardized selection differentials per generation over all lines for sires were .49, .46, 40, -.20, -.10, and .69, respectively, for initial weight, final weight, feed consumption, unadjusted feed efficiency, adjusted feed efficiency, and average daily gain. Selection of females for postweaning traits was not intense. Selection Indexes actually practiced in retrospect were: for sires, IS = .4661(WW) -.0092(FE) + .6126(ADG); for inbred dams, ID = .1824(WW) -.0284 (12W) + .0736 (18W) - 1097 (SPW) -.1097 (FAW); for linecross dams, ID= .2693 (WW) - 2960 (12W) + .0147 (18W) + 1185 (SPW) -.0354 (FAW). The corresponding index selection differentials were .818, 203, and .209. Sire index selection differentials represent about 79 percent of the total selection differentials.