Creating an Optimal Structure of the Diet to Increase the Productivity of Calves in Calves of Dairy Breeds

The diet of dairy bulls contains little high-quality protein. This primarily affects the main indicators of feed growth and conversion. Poor-quality protein in the diet leads to excessive formation of ammonia in the rumen. Increased concentrations of ammonia, does not participate in the synthesis of microbial protein and is excreted in the urine, which is an energy-consuming process and negatively affects the gains. Ammonia has a toxic effect, when an excessive amount of it enters the bloodstream, where it causes hyperamonymy, and creates an additional load on the liver. Aims: The aim of the study is to create an optimal structure of the diet, in which the protein will be completely utilized by the rumen microbiota and animal protein will be reproduced on its basis to create the growth potential of fattening bulls. The development of this diet will allow creating a technology for fattening steers for meat that is economically profitable with a high proportion of healthy animals with high productivity. Methodology: The studies were conducted on calves of the Kholmogorsky breed raised in the VNIIFBIP vivarium, aged from 1.5 months to 14 months. At the age of 1.5 months, the animals were intensively accustomed to the introduction of concentrates and coarse feeds. Feeding with a milk substitute was carried out up to the age of 70 days with free access to mixed feed and hay. Results: During the study, the main factors responsible for the metabolic processes in bull calves were identified. The factors of digestibility in the rumen were studied. Physiological and biochemical parameters were established to assess the reduction of the risks of hyperammonemia. The use of concentrated feed against the background of strict proportional administration together with coarse feed with intensive cultivation and fattening of dairy bulls and the normal course of enzymatic processes in the rumen and throughout the body allows you to achieve an average daily increase of up to 1420 g by 14 months of age and reduce feed conversion. Conclusion: The results obtained make it possible to increase the productivity of fattening steers in regions with a large number of dairy cattle and the availability of concentrated feed.

Impact of Management Factors on Seminal Attributes and Frozen Semen Doses Production in Holstein Friesian Crossbred Dairy Bulls

This study reports on important management factors that have impacts on semen characteristics, sperm production ability and cryo-preservability in dairy bulls. Except volume, bull types (FSD i.e. frozen semen dose producer vs Non-FSD bulls) differentiated most of the semen traits (P < 0.01). Age showed significant impacts on seminal attributes both in FSD and Non-FSD bulls. In FSD bulls semen traits increased significantly even up to 5 years age, in contrast, only 2 years in Non-FSD bulls. Overall semen quality index improved almost linearly with age advancement in FSD bulls (P < 0.01) but not in Non-FSD bulls, which showed very irrational trends. Seasons significantly (P < 0.01) influenced ejaculate characteristics. Overall semen quality, total sperm output and FSD production was the highest during summer and lowest in rainy seasons. Within a bull type (FSD/non-FSD) influence of age and season, and within age group impact of seasons was significant in most of the semen attributes. It was concluded that dependent on season, age of bull significantly influenced qualitative and quantitative attributes of semen; improvement being substantial in FSD bulls, but negligible in non-FSD bulls beyond 2 years age. Seasons of collection significantly influenced semen quality, sperm productivity and FSD production of bulls being highest in summer, followed by winter and least in rainy seasons. The study recommended that for effective FSD production, poor semen producer bulls should be culled as early as 2 years of age and during rainy season stress amelioration measures might mitigate FSD production losses from crossbred bulls.

Effects of different barley grain preservation techniques on intake, growth and carcase traits of finishing dairy bulls fed grass silage-based rations

The effects of different barley grain preservation techniques on intake, growth and carcase traits of dairy bulls were determined in a feeding trial using 52 Holstein and 48 Nordic Red bulls which were allotted to four feeding treatments (five pens and 25 bulls per treatment). Spring barley was harvested with a conventional combine harvester and four different preservation techniques formed the four experimental treatments. Dry grain (DG) was dried to the targeted dry matter (DM) concentration of 870–880 g/kg and rolled within 7 days prior to feeding. High moisture grain treated with a formic acid-based additive (FA) was harvested and crimped on the targeted DM content of 700 g/kg. Low moisture grain treated with a urea-based additive (UR) and low moisture grain treated with a propionic acid-based additive (PA) were harvested and crimped on the targeted DM content of 800 g/kg. The bulls were fed with total mixed ration ad libitum. On DM basis, the diets included grass silage (500 g/kg), barley grain (485 g/kg) and a mineral–vitamin mixture (15 g/kg). Daily DM intake (DMI) and live weight gain were 6% higher when crimped grains were used instead of DG (P < 0.05). There were no observed significant differences in DMI, gain or carcase traits between high moisture and low moisture crimped grain treatments or between UR and PA. The current results show that producers have the option to vary grain preservation system without major changes to growth performance or carcase traits.

Comparative characteristics of meat productivity of holstein and black-and-white breeds

It was assumed that the industry of beef cattle breeding being created in the Krasnodar Territory would meet the needs of the population in beef. Due to the fact that there are not enough beef cattle, dairy bulls are raised and fattened. Positive results are obtained in the case when, along with an increase in the number of the fattened livestock of animals, their intensive rearing and feeding is introduced. In our studies, with intensive rearing and fattening of the Holstein and Black-and-White bull calves, for the entire 14-month period of growing and fattening, average daily gains were obtained at the level of 1200 g, and the gross weight gain was more than 500 kg. According to the results of the slaughter of experimental bulls at the age of 14 months, we found that the Holstein bulls reliably exceeded the black-and-white bulls of the same age in all the studied parameters.

Study of the influence of the feeding type of calves during the milk fattening period on the subsequent growth and development of bulls up to 12 months of age

Research has been carried out on the intensive production of beef when raising dairy bulls up to 12 months of age drinking mainly dairy feed in the first 5 months of life (in group 1) and with the inclusion of a starter compound feed in the diet (in group 2). Different types of bull calves rearing in the first 5 months of life led to significant differences in the growth and development of the whole organism and all its individual organs and tissues, mainly in favour of bull calves raised with replacing part of the milk with vegetable feed, and subsequently had a decisive influence in the period from 6 up to 12 months of their life with the same type of feeding and maintenance. It has been established that the rearing system with a decrease in the drinking of whole milk and abstinence of the supply of roughage for the first 2 months of life, promotes the the growth of animals for a twelve-month period of life, leads to an increase in the yield of veal and beef meat, a decrease in feed consumption per unit of weight gain, and increasing the profitability of production by 8-9%, therefore it is recommended for production.

Use of SNPs from Illumina BovineSNP50K BeadChip v3 for imputation of microsatellite alleles for parentage verification and QTL reporting

The present study aimed to test the possibility of avoiding expensive retesting of the whole parental generation for single nucleotide polymorphisms (SNPs), to provide additional analysis of microsatellites in offspring in the transitional period and to analyse the likelihood of imputation of the International Society for Animal Genetics-recommended microsatellite markers from selected SNPs. The imputation and pedigree verification of 9 520 animals (representing 84 dairy bulls, 285 dairy cows, 3 202 beef bulls and 5 949 beef cows) were analysed by the method using 9 410 SNP haplotypes (incorporating an average of 73 SNPs per haplotype). The imputation method was confirmed to allow the parentage verification of up to 87% of the analysed animals without the need for retesting. The most problematic locus was TGLA53, with only 78% successful imputation. Seven loci (BM2113, ETH225, TGLA227, BM1824, SPS115, TGLA122 and TGLA126) had more than 90% imputing accuracy and success of imputation. The success of imputation also depends on the breed and the call rate of the test results. The highest imputation accuracy was found for the Holstein breed; the other six breeds had over 90% successful imputation rates, four breeds had imputation rates between 85.0 and 89.9%, and ten breeds (rarely bred in the Czech Republic) had imputation rates below 85.0%. A call rate of SNP tests lower than 90% indicates problems with haplotype construction and thus deterioration in the success of imputation. The analysis of a possibility of using all possible information from Illumina BovineSNP50K BeadChip v3 showed 109 SNPs encoding 51 quantitative trait loci markers. Haplotypes were designed for interpretation of the most important markers for diseases, exterior and performance. The most important markers for Holstein breeders were chosen as kappa- (variants A, B and E) and beta-casein (variants A1, A2), Holstein haplotypes affecting fertility (HH1, HH3, and HH4) and loci causing genetic defects, bovine leukocyte adhesion deficiency and deficiency of uridine monophosphate synthetase. The results estimated from bovine bead chips corresponded to the expected distribution of the incidence of these traits in the population and were verified by PCR-RFLP tests.

INFLUENCE OF FEEDING TYPE IN DAIRY PERIOD ON THE FURTHER GROWTH AND DEVELOPMENT OF CALVES UNDER INTENSIVE CULTIVATION

The research was carried out in the conditions of the farm of FGUP RPZ "Krasnoarmeysky" named after A. I. Maistrenko of the Krasnoarmeysky district of the Krasnodar territory. The aim of the research was to develop elements of technology of intensive beef production when raising dairy bulls up to 12 months of age with the inclusion of starter feed in the diet and drinking different amounts of dairy feed in the first 5 months of life. For the experiment, black-andwhite bulls were selected from the age of 4 days, divided into 2 groups of 12 heads each. Bulls, which in the first five-month period of life replaced half of the dairy feed with starter feed and other feeds, showed increased growth and development of the gastrointestinal tract and other organs in the subsequent 6-12 month period of cultivation and fattening, they had an increased energy of average daily growth of 1142.8 g, surpassing the animals of the 1st group. In the first 5-month period of growing, the limited replacement of part of the dairy feed with mixed feed starter, abstinence with the supply of coarse feed in the first two months of life had a positive effect on the development of the gastrointestinal tract, heart, lungs, tongue and head, as well as the intensity of growth, compared to analogues that received milk and hay. After the milk period of 6-12 months of growth and development, the positive effect of pre-enhanced development of organs (including the pre-ventricles) continued. Differences in the growing of calves in the first 5 months had an impact on the histological state of the tissues of the scar, mesh and abomasum, which also affected the differences in the growth rate of calves-analogues.