First-calf Heifers Research Articles

Comparative analysis of the results of BLUP-evaluation of sires of diffirent countries origin by the conformation of their daughters

In breeding work one of the priority areas is the improvement of the genetic potential of animals, the effectiveness of which depends on the accuracy of determination and prediction. The method of constructing, optimizing and solving the equations of mixed models for predicting the breeding value of animals is becoming increasingly important, which is based on the principle of maximizing the relationship between sires evaluations based on the characteristics under consideration (BLUP method). One of the important economic indicators in cattle breeding concerning the increase in productivity and the term of their economic use of animals, is the evaluation of sires by the type of conformation of daughters, based on the calculation of breeding value indices. The researches on monitoring and comparative analysis of changes in the genetic value of breeding bulls by the conformation features of off spring at the population level of Black-and-White cattle in the Moscow region have been presented in the article. Groups were formed in the context of the sires’ origin according to countries. The formation of a database on the indicators of the conformation of first-calf heifers has been carried out on the basis of the analysis of materials from the regional information and breeding center of breeding livestock in the Moscow region Mospleminform. In a comparative aspect, evaluations of the breeding value of sires of Russian origin were taken with sires were born in the Netherlands, Germany, Denmark, Canada and the USA. The results of the research have shown that the main emphasis of the breeding of bulls of Russian origin was aimed at strengthening the body traits. The data of the comparative analysis of the variability of the genetic value of sires by the type of conformation of daughters carried out according to the BLUP procedure provide an opportunity to monitor and analyze the direction of breeding work when organizing the selection of parental pairs.

ЭФФЕКТИВНОСТЬ СКРЕЩИВАНИЯ БЕСТУЖЕВСКИХ КОРОВ С БЫКАМИ КРАСНОЙ ДАТСКОЙ ПОРОДЫ

The article presents results of studies on milk productivity of crossbred first-calf heifers obtained by crossing Bestuzhev cows with red Danish bulls. Feeding of both groups (control and experimental) was carried out with proper and balanced ration. Total nutritional value of the ration was 14.07 energetic feed units (EFU). One EFU accounted for 85.15 g of digestible protein, dry matter per 100 kg of live weight - 3.6 kg, fiber from dry matter - 23%. Sugar - protein ratio of the diet was at the level of 0.8. As a result, crossbred first-calf heifers had higher parameters of milk yield (by 20.57%), fat content (by 0.23%) and protein (by 0.07%) in milk compared to pure-bred Bestuzhev peers; they had also higher milking capacity index (by 14.14%). In addition, crossbred first-calf heifers show better development, their live weight is 26 kg or 5.64% higher than the level of the breed minimum requirements. Consequently, the effect of heterosis is noted when crossing Bestuzhev cows with red Danish bulls, which has a positive effect on better development of crossbred heifers and on increase of their milk productivity. As a result, crossbred first-calf heifers meet the modern requirements of milk production technology on an industrial basis better than their Bestuzhev peers. Therefore, this method of crossing with the red Danish breed is advisable and should be used in selection and breeding work with the Bestuzhev breed.

A phenotypic characterization of Rarámuri Criollo cattle introduced into the Southwestern United States

Our objective was to describe key phenotypic characteristics of a population of Rarámuri Criollo (RC) cattle introduced from the Copper Canyon of Chihuahua, México into the Southwestern United States almost two decades ago. We recorded 26 phenotypic traits of 37 RC individuals including mature cows, first-calf heifers, and mature bulls raised at the USDA-ARS Jornada Experimental Range in southern New Mexico. This herd of RC cattle exhibited intermediate body sizes compared to the smaller Corriente and larger Texas Longhorn and Florida Cracker cattle. Coat colors were similar to those described for other Criollo biotypes but horn shape and size of RC appear to be different than that of other US-based Criollo breeds. Though smaller than commercial beef breeds, RC cattle appear to be well-matched to the Southwestern US environments as evidenced by previous studies that evaluated their grazing behavior, weight gains, and carcass quality. Rarámuri Criollo cattle are a genetic resource whose conservation could be critically important for climate change adaptation of ranches in the desert Southwest.

Realization of the potential of cows of Holstein breed of different generations in terms of productive traits

Breeding work with dairy cattle in the Kurgan region is aimed at breeding animals that combine the adaptive properties and valuable traits of cattle of Black-and-White breed with a high proportion of genes of Holstein breed. Such animals are characterized by high productivity and suitability for intensive technology of their housing. The purpose of the research was to determine the indicators of milk productivity of first-calf heifers of different generations of Holstein breed, imported to the pedigree farms of the Kurgan region, as well as to determine the degree of realization of the genetic potential of animals. Scientific research has been carried out in the herd of CJSC “Glinka” (Kurgan), where highly productive cattle of Black-and-White and Holstein breeds are bred. The subject of research was the first-calf heifers of the imported Holstein breed of German selection of different generations, as well as the herdmates of Black-and-White breed. It has been found that the realization of the genetic potential for milk yield in Holstein cows of German breeding was higher and amounted to 76,4 %, in cows of Black-and-White breed 69,9 %. The highest milk yield for 305 days of lactation has been observed in the second generation of Holstein heifers 8905 kg, which exceeded the milk yield of herdmates of the second and third generations by 113 kg or 1,26 % and 174 kg or 1,95 %, respectively. The mass fraction of fat in German Holsteins of different generations ranged from 3,99 to 4,21 % (P < 0,001), while the mass fraction of protein in the milk of first-calf heifers varied slightly in the range from 3,18 to 3,20 %. In terms of live weight, the animals of the third generation slightly exceeded the herdmates of the 1st and 2nd generations by 19 kg or 3,25 % and 20 kg or 3,43 %, respectively. The largest profit has been received from the first-generation first-calf heifers of Holstein breed of German selection, where the level of profitability of milk production was 50,7 %, which was higher than that of the herdmates of the second and third generations by 3,9 and 7,9 %, respectively.

Milk productivity of cows depending on their origin on genealogical line

The improvement of cattle of Black-and-White breed by mating of maternal stock with the sires of Holstein breed continues at the present time. Therefore, breeding in pedigree farms for the production of milk is carried out including the use of Holstein lines. The purpose of the work was to assess the milk productivity of cows of Black-and-White breed, with a high proportion of blood in Holstein breed, depending on their linear origin. In the herd of the breeding farm where the research has been carried out, the lines Reflection Sovereign 198998 and Wes Ideal 933122 occupy the dominant position in terms of the specific weight of cattle, followed by the line Montwick Chieftain 95679. The difference in milk yield between groups of cows of different lines was from 3,0 to 354 kg or 0,04 to 4,6 %. The highest milk yield was shown by the first-calf heifers of the line Wes Ideal 933122 – 7787±123,21 kg. In the milk of the first-calf heifers of the line Pabst Governor 882933 compared with herdmates of other lines the increased content of fat and protein has been noted,. The difference in the mass fraction of fat in milk was significant in favor of Pabst Governor 882933 cows (P ≤ 0,01–0,001). There was also the significant difference in the mass fraction of fat in milk between the groups of cows of the lines Montwick Chieftain 95679, Reflection Sovereign 198998 and Wes Ideal 933122 in favor of the latter at P ≤ 0,05–0,01. A definite association between milk yield and the mass fraction of fat in milk has not been established. There is a pattern of the positive association between the mass fraction of fat and the mass fraction of protein in milk and it is clearly seen that with the increase in the mass fraction of fat in milk, there is the increase in the mass fraction of protein.

Influence of a complex feed additive on the morphological and biochemical parameters of the blood of first-calf heifers during the period of increasing the milk yield

It is known that mineral additives play an important role in increasing the productivity and efficiency of the animal husbanry industry as a whole. The state of the body can be assessed by the content of mineral substances in a blood test. The purpose of the work was to study changes in morphological and biochemical blood parameters in first-calf heifers during the period of increasing the milk yield when they are fed a complex mineral and vitamin feed additive (CMVFA). The study of the influence of feeding the complex mineral and vitamin feed additive in the ration to first-calf heifers during the the period of increasing the milk yield on morphological and biochemical blood parameters has been carried out. The experiments were carried out in 2019–2020 in the OOO Breeding Farm “Valiev” in the Dyurtyulinsky district in the Republic of Bashkortostan on 3 groups of first-calf heifers of Black-and-White breed per 15 heads in each selected by the method of pairs of analogues. The animals of the control group received the main ration (MR) adopted on the farm, the 1st experimental group MR+120 g/head CMVFA according to the recipe No. 1, the 2nd experimental group MR+120 g/head CMVFA according to the recipe No. 2. In the ration of animals of the control group there was a deficiency of basic macro- and microelements. The use of CMVFA as part of the ration of first-calf heifers during the period of increasing the milk yield had a positive effect on the morphological and biochemical parameters of blood. Studies have shown that the use of CMVFA in the rations of first-calf heifers provided the need for minerals and vitamins, accelerating metabolic processes in the body during the most stressful period of lactation, the period of increasing the milk yield. According to the results of biochemical blood parameters, it is possible to esimate the improvement of protein, carbohydrate and mineral and vitamin nutrition in the first-cakf heifers of the experimental groups during the period of increasing the milk yield, which showed their genetic potential more fully and used nutrients more effectively for milk synthesis.

THE PROLONGED INFLUENCE OF PROBIOTIC PROTECTION OF MUCOSY COWS BEFORE INSEMINATION ON THE EXPRESSION OF THE PRODUCTIVE POTENTIAL OF THEIR FIRSTBORN DAUGHTERS

The aim of our study was to determine the prolonged delayed action of probiotic feed protection of the intestinal mucosa of cows in the period before fertilization for the manifestation of the productive potential of their daughters during the first lactation.
 Analytical work was carried out during the 2016-2019 economic years, the experimental part of the study was carried out on the basis of a dairy complex-breeder of Ukrainian red dairy cattle (700 dairy heads), located in Odessa region.
 The results of a scientific and industrial study of a number of indicators of productivity of replacement heifers / heifers / heifers of the Ukrainian red dairy breed showed that the use of the feed probiotic preparation "Veterinary Multibacterin Bs + La suspension - feed mixture" together with the main diet of mothers before artificial insemination gave a positive prolonged effect on the manifestation of the productive potential of their half-siblings. For standard lactation, first-calf heifers in the experiment had a higher milk productivity by 6.99 % (respectively: 8121 and 7540 kg per head, P <0.05). At the same time, the first-calf heifers of the experimental group had a more physiological term for the interstitial period, namely: 425.39 days, which was 56.28 days shorter than in the control and contributed to the profitability of production.
 It has been experimentally established that probiotic protection of the intestinal mucosa of mothers cows has a positive effect on the quality of the offspring, which forms the next generation of the breeding herd.

Heat synchronization and the effectiveness of insemination of cows of Holstein breed under the conditions of the dairy complex

The food security of country is largely determined by the development of animal husbandry branches. Dairy cattle breeding is of particular importance, which has been actively developing in recent years due to the modernization of farms and complexes, the introduction of innovative technologies and the formation of a highly productive breeding herd. The most important link in the development of dairy cattle breeding is the reproduction of the herd. Modern technologies make it possible to use hormonal drugs in order to optimize the reproductive traits of animals. The results of clinical and experimental studies have shown the important role of hormones in the regulation of physiological functions, as well as the possibility of their use for directed changes in metabolism, productivity and fertility of animals. The purpose of the research was to assess the influence of methods of synchronization of heat of cows on the pregnancy rate under the conditions of the dairy complex. The research data on the effectiveness of insemination when identifying animals in visually heat and using Heatime neck strips, as well as when using heat synchronization programs such as Presynch and Double Ovsynch have been presented in the article. The research has been carried out under the conditions of a modern dairy complex on a highly productive herd of cows of Holstein breed. Differences in the effectiveness of insemination by using the studied methods were revealed from 49,1 to 72,5 %. The highest conception rate has been observed in first-calf heifers (83,0 %) and cows (62,5 %) inseminated using the Double Ovsynch protocol. The dependence of the level of conception rate on the presence of diseases suffered by cows during the newcalving period and until the moment of insemination has been noted. In sick animals, the conception rate for groups of first-calf heifers and cows was significantly lower than in healthy animals. Thus, according to the Double Ovsynch insemination protocol, the conception rate in healthy animals was 83,7 %, and in those who were ill – 65,2 %. The research results confi rmed the validity of stopping the use of the Presynch protocol and completely transferring the dairy herd of cows to synchronization and insemination using the Double Ovsynch protocol.

ГЕНЕТИЧЕСКАЯ ИЗМЕНЧИВОСТЬ ОЦЕНКИ ТЕЛОСЛОЖЕНИЯ КОРОВ - ПЕРВОТЕЛОК ГОЛШТИНСКОЙ ЧЕРНО-ПЕСТРОЙ ПОРОДЫ РАЗНЫХ ЛИНИЙ

Exterior assessment is important for specification of constitutional strength of an individual animal and its acclimatization ability, as well as its productive orientation. The object of our research was Holstein first-calf heifers of the black-and-white breed prevailing on the farms of Moscow region. Studies were conducted with application of linear estimation of the animal body type of 54,170 animals. Animals are divided into 5 groups depending on the lineage: Vis Back Ideal 1013415, Reflection Sovering 198998, Pabst Governer 882933, Montvik Chieftain 95679 and other lines. Most of the animals had parameters in the range of 4 ... 6 points. With greater reliability (p≤0.001) and in the course of the dispersion analysis, it was found that it affects the rump bone height, position of the quarters, the height of the back lobes, the length of the nipples, the width of the quarters and the angle of the back legs from the side (p≤0.01). The heritability of the rump bone height (0.27 ... 0.38) and milk type (0.16 ... 0.36) in almost of all studied lines was within moderate limits. A high occurrence of such constitutional defects as soft ankles (4.16 ... 13%), oblique udder bottom (1.78 ... 5.02%), high tail (2.75 ... 8.07%) and roof-like quarters (1.08 ... 3.77%) was noted in such lines of first-calf heifers as Vis Back Ideal 1013415, Reflection Sovering 198998 and Montvik Chieftain 95679. Animals of all the studied groups have high genetic correlations between the rump bone height and other parameters of constitutional assessment: Montvik Chieftain line has 95679 positive pairs 8 ( 0.63 ± 0.0032 ... 0.97 ± 0.0005) and 5 negative pairs (-0.66 ± 0.0041 ... -0.97 ± 0.0045); Vis Back Ideal 1013415 - 2 positive pairs (0.48 ± 0.0007... 0.66 ± 0.0006); Reflection Sovering 198998 - 4 positive pairs (0.41 ± 0.0009 ... 0.62 ± 0.0007); Pabst Governer 882933 - 3 positive (0.55 ± 0.0092 ... 0.74 ± 0.0071) and 2 negative pairs (-0.62 ± 0.0174). The obtained results reveal wide selection possibilities in dairy herds.

ЭКСТЕРЬЕРНО-КОНСТИТУЦИОНАЛЬНЫЕ ОСОБЕННОСТИ КОРОВ - ПЕРВОТЕЛОК ЧЕРНО-ПЕСТРОГО СКОТА ПРИ РАЗНЫХ СОЧЕТАНИЯХ ПОДБОРА

The development of dairy cattle breeding largely depends on the culture of young cattle breeding. It is very difficult to obtain and preserve young animals. Correct rearing of young cattle of dairy breeds contributes to the appropriate exhibition of genetically inherent productive abilities of animals during the first stage of their growth and development. When organizing breeding and feeding, animal growth and development characteristics are taken into account, which are determined by heredity and environmental conditions, especially feeding. The article provides a comparative analysis of the dynamics of live weight, measurements and body indexes of first-calf heifers of various selection combinations. First-calf heifers of the fifth experimental group, obtained from fathers and mothers belonging to the cross lines, exceeded animals in the control group, whose parents belonged to pure lines, in live weight and gains. Under the same housing and feeding conditions, the heifers of the studied groups did not grow in the same way, and certain differences were revealed in the process of ontogenesis. The first-calf heifers of the 5th group had the greatest live weight in different age periods and exceeded the peers of the 1st, 3rd and 4th groups from 10 to 23 kg with relevant difference. The animals of the 5th experimental group had the highest average daily gains till 6 months old. For the entire growing period (18 months), the animals in the control group had the highest relative gain, which was significantly higher than the gain in the experimental groups. The following body indexes were calculated: long-legged, elongation, pelvic-thoracic, thoracic; blockiness and bone index, as well as milk production coefficient which determined the direction of productivity of animals. First-calf cows were included into dairy-meat productivity direction according to the long-legged and elongated index. According to blockiness and thoracic index, animals of all groups belong to dairy direction of productivity, and according to bone index, to meat direction.

Comparative effectiveness of the use of wet flattened corn grain in the rations of lactating cows

In order to effectively provide the body of cows with energy during the increasing the milk yield without the risk of acidosis, progressive animal breeders of the Altai Territory include wet flattened corn grain in the composition of concentrated feed. The question of the expediency and economic effectiveness of using wet flattened corn grain for cows of various physiological groups – first-calf heifers and mature animals continues to be debatable. Therefore, a comparative assessment of two options for feeding wet flattened corn grain to cows under the conditions of the Altai Territory is considered promising in modern animal husbandry and is of great practical interest. The purpose of the work was to identify the optimal and economically feasible option for using wet flattened corn grain in the rations of lactating cows. When using wet flattened corn grains in an amount of 7,1 % of the nutritional value of the ration the first-calf heifers during the period of increasing the milk yield, productivity has increased by 20,9 %. The average daily milk yield was 17,3 kg, which significantly exceeded the indicator of the control group (P > 0,95). The inclusion of wet flattened corn grains in the ration of mature cows in the amount of 1 kg for 30–35 days before calving, then 4,5 kg from 15 to 75 days after calving allows us to get the average daily milk yield of 30 kg or 20,3 % higher than that of the control group of herdmates (P > 0,95). The effectiveness of the use of wet flattened corn grain had significant indicators: the total profit from the sale of dairy products of the first-calf heifers of the experimental group amounted to 16 251,3 rubles/head, and from the sale of milk of mature cows of the experimental group it was 30 346,43 rubles/head.

Dynamics of pneumatic drive of devices for udder massage of animals

The paper presents the results of theoretical developments on the deformation of flexible shells of the executive bodies of the means of stripping, the assessment of their mechanical impact on the udder of the heifer and first-calf, the dynamics of the pneumatic drive of the executive bodies. The design and technological parameters of the devices for milking first-calf heifers and massaging the udder of heifers are justified, the set and duration of technological operations for animal milking and the economic efficiency of their implementation are determined.

Evaluation of Brix Refractometry to Estimate Immunoglobulin G Content in Buffalo Colostrum and Neonatal Calf Serum.

Simple SummaryThe protective effects of colostrum in relation to the incidence and severity of newborn ruminant diseases are well established. Neonatal calf depends on the timely supply of high-quality colostrum to prevent the failure of passive transfer of immunoglobulins (Ig), which has been linked to increased risk of different diseases and mortality in early stages of life. Despite the relevance of Buffaloes (Bubalus Bubalis) in world dairy production, the available knowledge regarding colostrum quality management remains scarce for this species. Therefore, the objective of this study was to evaluate the utility of a simple and rapid tool such as a digital Brix refractometer to estimate colostrum quality and for predicting the success of passive transfer of immunoglobulin G (IgG) in Buffalo calves. For this aim, correlation analysis was performed between Brix results and ELISA-IgG determination from colostrum and serum samples. A strong correlation was found between Brix measurements and IgG content in colostrum and serum samples. Moreover, cut point values for Brix measurements for colostrum and serum samples were determined. Brix refractometry was found to be an acceptable tool for on-farm estimations of colostrum quality and passive immunity transfer (PIT) in Buffalo calves.Brix refractometry has been widely demonstrated to be a useful tool for monitoring colostrum management program and passive immunity transfer (PIT) in Bovines, but its suitability has never been verified in Buffalo. Therefore, the objective of this study was to evaluate the utility of a simple and rapid tool such as a digital Brix refractometer to estimate colostrum quality and for evaluating the success of passive transfer of immunoglobulin G (IgG) in Buffalo calves. The optimal cut points levels for Brix Refractometry for distinguishing good- and poor-quality colostrum and for assessing the adequacy of passive immunity transfer in calves were determined. For this aim, 26 first-milking maternal colostrum (MC) were collected from first-calf heifers. Blood samples were obtained from their calves at birth (T0) and 72 hours after (T3). Colostrum and Serum IgG content were determined by indirect enzyme-linked immunosorbent assay (ELISA), whereas total protein (TP, g/dL) and percentage Brix (%Brix) by means of a digital Brix refractometer. The mean colostrum IgG was 64.9 ± 29.3 mg/mL. The mean serum %Brix at T3 was 9.6 ± 0.9 %. The mean serum IgG content at T3 was 11.1 ± 2.0 mg/mL. Pearson’s correlation coefficient (rp) was determined between Brix and ELISA measurements: colostrum %Brix showed a significant correlation with serum %Brix (rp = 0.82, p < 0.001); serum %Brix was highly correlated with serum TP (STP, g/dL) (rp = 0.98, p < 0.001) and serum IgG (mg/mL) (rp = 0.85, p < 0.001). A cut point of 18% Brix to estimate samples of MC ≥ 50 mg/mL from first-calf heifers was more appropriate for the buffalo. A cut point of 8.4% Brix resulted in the greatest percentage of calf serum samples being correctly classified. Based on our findings, a digital Brix refractometer could be a useful tool to monitor colostrum quality and to estimate PIT in Buffalo calves.

Adaptive features of the Simmental breed cattle in conditions of the Lower Volga region

The article presents the results of identifying parental line of Simmental cattle the most stable to aggressive environmental conditions in the Lower Volga region with high milk productivity. The experimental work was carried out at farm-breeding plant named after Lenin of Surovikinsky District of Volgograd Region. All of cows of the farm was distributed among the bulls of different lines, which were selected individually for each one. In total 79 first-calf heifers and 249 full-aged cows participated in the experiment. The assessment of milk productivity of the cattle population was carried out on the basis of data of SELEX program. Productivity of bulls daughters belonging to different breeding lines was examined. Also, as part of the work, the parameters of natural resistance-innate level were studied. The results obtained during the experiment were processed and analyzed using standard methods. it was concluded the most preferred line of cattle for breeding in farm-breeding plant named after Lenin of Surovikinsky District of Volgograd Region.

Productive qualities of Holstein black-and-white cattle of different genotypes according to kappa-casein

In Sverdlovsk region Holstein black-and-white cattle of the Ural type are bred, which are represented by highly productive animals with a high genetic potential for productivity. The aim of the work was to study the effect of genotypes of the kappa-casein gene on milk productivity and quality indicators of milk from Holstein black-and-white cattle of the Ural type. Most of the cows had the AA kappa-casein genotype, and they had the worst indicators of technological properties in terms of cheese suitability. The best technological properties of milk are possessed by cows with the BB kappa-casein genotype. There were only 4.2% of such animals among those examined. The highest milk yield in 305 days of lactation was observed in cows with the genotype for BB kappa casein (9595 ± 314.3 kg), which is 373 kg and 537 kg more, or 3.9 and 5.6% more than in animals with AA and AB genotypes, respectively. The indicators for the mass fraction of fat and mass fraction of protein in the milk of cows of different genotypes for kappa-casein were the same. There was a tendency to an increase in the protein content in the milk of cows with the BB genotype and a decrease in the mass fraction of fat in the milk of cows with the AB genotype. Thus, more nutrients, namely milk fat with the same content in milk, were obtained in the group of first-calf heifers with the BB genotype (380 ± 13.19 kg). They also had a higher yield of milk protein (311 kg), which is more than in other groups by 13 and 19 kg.

Influence of live weight on milk productivity and longevity of economic use of cows

The purpose of the research was to study the influence of the live weight of first-calf heifers on the subsequent milk productivity and productive longevity of high-blood Holstein animals. Research has shown that live weight influence on dairy productivity and productive longevity of cows. From cows with genotype 1/4S+1/4A+1/2RWH with a live weight of 580–600 kg for the first lactation 750 kg more milk was produced than from cows with the live weight 480–500 kg at the first calving. With an increase of the part of Holstein breed blood the differences in milk productivity between cows with different live weight during the first lactation have been increased. First-calf heifers with genotype 1/8S+1/8A+3/4RWH with the live weight of 580–600 kg outperformed their herdmates with the live weight 480–500 kg in milk yield by 1761 kg (P ≥ 0,999), and cows of genotype 1/16S+1/16A+7/8RWH by 2271 kg of milk (P ≥ 0,999). Indicators of productive economic use had certain differences. Thus, cows with the genotype 1/4S+1/4A+1/2RWH with the live weight of 540–560 kg had the highest longevity of economic use – 43,29 months and a lifetime productivity – 24942 kg of milk. In crossbred cows with genotype 1/8S+1/8A+3/4RWH the longevity of economic use and lifetime productivity were higher in cows with the live weight of 580–600 kg, the indicators were 24,73 months and 18294 kg of milk, respectively, in cows with genotype 1/16S+1/16A+7/8RWH the highest longevity of economic use 24,96 months was in cows with the live weight of 560–580 kg, and lifetime productivity – 18131 kg in cows with the live weight 580–600 kg.

Productive and reproductive traits of first-calf heifers of different origin under the conditions in LLC “Green lines – Kaluga”

Dairy cattle breeding have always occupied and will continue to occupy one of the leading places in the agro-industrial complex in our country. The most eff ective method of improving existing breeds according to opinion of a number of scientists is selection in line breeding. At the same time the evaluation of breeding sires by the quality of offspring is the cornerstone of breeding work. The purpose of the research was to analyze the influence of breeding sires, as well as their linear affiliation on the economically useful characteristics of first-calf heifers under specific conditions of maintenance and use. An analysis of the milk productivity and reproductive traits of first-calf heifers of different origin by sires and different line belonging has been presented in the article. The results of intra-linear selection and crosses of genealogical lines and their influence on the productive and reproductive traits of first-calf heifers have been evaluated. The research was carried out in LLC “Green Lines-Kaluga” of the Kaluga region. It has been established that for fixing in the genotype of the offspring of plentiful milk and fat milk in purebred breeding, it is necessary to use the following sires: Aragon 2102, Tabor 1292, Lira 2047, Phlox 1448, Chudny 1167, Yalik 397, Tabun 1277, as well as intra-linear selection in the line of Montwick Chieftain 9567929 and crosses of lines in combinations: Siling Traijun Rocket 252803 – Reflection Sovereign 198998 and Wes Ideal 933122 – Siling Traijun Rocket 252803. In order to reduce the age of the first insemination of maternal stock we recommend using a combination of lines: Wes Ideal 933122 – Montwick Chieftain 9567929, Wes Ideal 933122 – Reflection Sovereign 198998, Montwick Chieftain 9567929 – Wes Ideal 933122, Montwick Chieftain 9567929 – Reflection Sovereign 198998 and Siling Trijun Rocket 252803 – Wes Ideal 933122.

The effectiveness of feeding complex mineral and vitamin feed additive «Nadezhda» to lactating cows

The feasibility of using the complex mineral and vitamin feed additive “Nadezhda” in the rations of lactating first-calf heifers of Black-and-White breed has been examined in the article. It has been established that feed contain a low content of elements such as calcium, phosphorus, magnesium, sulfur, manganese, copper, zinc and cobalt. The ratio of nutrients and minerals, the degree of their availability for assimilation by the body does not provide their need. The use of the complex mineral and vitamin feed additive contributed to an increase in the milk productivity of first-calf heifers and the quality of milk, feed consumption per unit of production. All tested recipes of the complex mineral and vitamin feed additive, which have different versions of macro-, microelements and vitamins in their composition had a positive effect on the metabolic processes in the body of animals. For the production of 1 kg of milk in the experimental groups of cows less metabolic energy was spent by 5,09 (P &lt; 0,05) and 8,06 % (P &lt; 0,05), respectively, raw protein by 5,19 and 8,19 % (P &lt; 0,05), digestible protein by 5,12 (P &lt; 0,05) and 8,15 % (P &lt; 0,05) compared with the animals of the control group. At the same time from the cows of the 1st experimental group have been received more milk by 151,6 kg in the amount of 2489 rubles, from the 2nd experimental group by 250,6 kg of milk in the amount of 4248,0 rubles. The prime cost of production of 1 kg of milk in cows of the 1st experimental group in comparison with the animals of the control group decreased by 0,72 rubles, and the 2nd experimental group by 1,21 rubles. The level of profitability of milk production in cows have been fed with additive recipe No. 1, in comparison with the animals of the control group increased by 3,71 abs.%, recipe No. 2 by 9,91 abs.%.

Evaluation of first-calf heifers of Red Steppe breed by indicators of milk productivity and live weight under the environments of Yakutia

The purpose of the work was to evaluate the milk productivity and live weight of first-calf heifers of Red Steppe breed belonging to different genealogical lines under the economic conditions of Central Yakutia. In order to increase the gross milk production and increase the number of breeding cattle in the Municipal Unitary Enterprise “Chuya” in the Megino-Kangalassky ulus Red Steppe heifers were imported from the Altai Territory. The main factor in increasing the breeding and productive traits of dairy cattle is the feeding of livestock, i.e. for the express of the genetic potential of the herd it is necessary to house the animals under conditions that promote the full realization of their genotype. In the daily ration of lactating cows of the farm the content of energy feed units and digestible protein was 89,9 and 107 % of the feeding norm, respectively. In the ration, the sugar-protein ratio was 0,43, which indicated a lack of carbohydrate nutrition. In terms of milk yield per lactation the first-calf heifers of the line Hoyager 51 have been serpassed the offspring of the line Montwick Chieftain 95679 by 185 kg of milk or 7,7 % (P &gt; 0,99), and the line Corbitz 16496 by 90 kg or 3,75 % (P &gt; 0,99). There were no significant differences in the fat and protein content in the milk of cows of the compared lines (P &lt; 0,95). The higher-yielding first-calf heifers of the line Hoyager 51 had better milk fat and protein yield compared to the herdmates of the line Montwick Chieftain 95679 by 6,8 kg or 8,0 % (P &gt; 0,99) and 6,0 kg or 7,8 % (P &lt; 0,95), and the line Corbitz 16496 by 3,4 kg or 3,8 % (P &gt; 0,95) and 5,2 kg or 6,7 % (P &gt; 0,95), respectively. The live weight of first-calf heifers of the line Hoyager 51 was more by 14,5 kg or 3,9 % (P &gt; 0,95) than the first-calf heifers of the line Montwick Chieftain 95679, and the first-calf heifers of the line Corbitz 16496 by 6,5 kg or 1,7 % (P &lt; 0,95).

Evaluation of the productive qualities of donor cows and cow’s families by transmission capacity

Purpose: To assess the productive qualities of donor cows, taking into account the transmitting capacity of their families. To study the possibility of using this criterion to predict the breeding qualities of descendants.Materials and methods. The assessment of the transmitting ability of animals was carried out according to the System for assessing the breeding qualities of dairy cattle by transmitting ability (2010). A genealogical database of first-calf heifers in herd «Petrovsky» (more than 9500 heads) has been formed. The estimation of the transmitting capacity of productive traits of 111 families, to which 132 cows from the donor herd belonged, was carried out.Results. It was found that 44 donors belonged to the «best» families in terms of milk yield and 348 embryos were frozen from them. From 31 donors from the «worst» families in terms of milk yield, 199 embryos were frozen. Linear profiles of families were compiled according to the characteristics of their transmitting capacity for five indicators of milk productivity. It is shown that the probability that the descendants of cows from the «worst» families in terms of transmitting ability will have high rates for the trait we are interested in is approximately 18–20%. In families of the «best» category, this probability is 45% or more.Conclusion. Evaluation of productive traits in terms of transmitting capacity is an important additional criterion when choosing the most valuable cows as embryo’s donor. Compilation of linear profiles of families allows you to obtain objective information about their breeding value in relation to productive traits.