Red Steppe Cattle Research Articles

Влияние генотипа крупного рогатого скота на химический состав говядины

Purpose. To study the slaughter qualities of mixed young cattle and the chemical composition of beef obtained from it. Materials and Methods. The object of research is 18-month-old crossbred bulls, obtained as a result of industrial crossing of Kazakh white-headed cattle bulls with heifers of the Simmental breed (group I), Hereford bulls with heifers of the Simmental breed (group II) and Kalmyk bulls with heifers of red steppe cattle (group III). Purebred bulls of the Kazakh white-headed breed were used as a control group. Chemical analysis of beef samples was carried out according to the following methods and GOST standards: moisture content was determined by drying the sample to a constant mass at a temperature of 100-105 °C according to GOST 9793-2016; protein content – by the amount of protein nitrogen by the Kjeldahl method according to GOST 25011-2017; fat content – according to GOST 23042-2015; ash content – according to GOST 31727-2012; the amino acid and vitamin composition was determined according to the method of measuring the mass fraction of amino acids and vitamins by the KE method on the Kapel-105M system, the concentration of hydrogen ions (pH) according to GOST R 51478-99. Calorie content of 100 g / meat was calculated using the formula of V. M. Aleksandrov. Results. To assess the meat productivity of crossbred steers, their control slaughter was carried out, which showed that the largest slaughter weight and slaughter yield were possessed by steers of the II experimental group – 312.4 kg and 61.0%. Beef samples from young animals of the II experimental group had the highest content of dry matter. The difference with peers from the control, I and III groups was 0.27, 0.21 and 0.63%, respectively. It was also noted that the crossbred young of the II experimental group surpassed purebred Kazakh white-headed bulls in protein content by 1.67%. The difference with the crossbreeds from group I and III is 1.38 and 2.3% respectively. A study of the vitamin composition of the beef of experimental young animals showed that the resulting beef was relatively rich in vitamins of group B. beef obtained from crossbred bulls of the II experimental group has a higher biological value (Protein qualitative indicator = 5.86 compared with the control 5.59). The increase in protein qualitative indicator is mainly due to the higher content of tryptophan in beef of the experimental group II – by 9.0% (494.40 mg% compared with 453.86 mg% in the control). The pH value of the water-meat extract in bulls of different genotypes is almost the same and ranged from 5.41 to 5.49. Conclusion. It has been established that the crossing of bulls of meat breeds of cattle with heifers of dairy and combined breeds contributes to the production of young offspring with excellent slaughter qualities, and beef obtained from such offspring has a high biological value.

Analysis of polymorphisms in genes associated with milk productivity in red steppe and Caucasian brown cow breeds in two natural‐climate zones (mountains and plain) of Dagestan, Russia

Aim. The unique gene pool of indigenous breeds in the Dagestan Caucasus is threatened by the increasingly widespread use of commercial breeds, which in turn risks narrowing the genetic base necessary to increase and maintain existing genetic diversity. For this reason, our research aimed to study the polymorphism of the PRL, PIT‐1, GH genes in red steppe and Caucasian brown cattle raised in the conditions of Dagestan.Methods. Genotyping of red steppe and Caucasian brown cattle was carried out using PCR‐RFLP methods. Using these methods, genetic analysis was carried out and polymorphism of the prolactin, somatotropin and pituitary‐specific transcription factor genes was studied.Results. As a result of the genotyping of an experimental group of red steppe cattle, it was found that the distribution of two alleles and three genotypes (PIT‐1A and PIT‐1B; PIT‐1AA, PIT‐1BB, PIT‐1AB) of the PIT‐1 gene has a specific character. The specificity of the allelic spectrum of the PRL gene is expressed in the high (0.84) frequency of occurrence of the PRLA allele and low (0.16) frequency of the PRLB allele. This is reflected in the presence of homo‐ and heterozygous genotypes with a frequency of occurrence of 73.0; 23.0; 4.0 %, respectively.Conclusion. Applied genetic approaches to improve the productive and breed qualities of livestock, which are modern and based on a more complete analysis of the genetic diversity and genotype of the studied populations, contribute to the conservation of zoned breeds. At the same time, intrapopulation variability and good adaptability should ensure the sustainable development of dairy cattle breeding in various climatic zones.

Polymorphic variants of the PIT-1 gene in simmental and red steppe cattle of the Republic of Kazakhstan

The search and identification of genes responsible for economically useful traits of cattle is relevant. Dairy productivity as a complex quantitative trait, is controlled by a large number of genes and their transcription factors taking into account the physiology of the animal. The dynamics of dairy productivity depends on a number of factors, since the secretory activity of the mammary gland is controlled by a complex of hormones, genes, transcription factors and enzymes. The studied gene Pit-1 (POU1F1) is an informative marker in determining milk and meat productivity. The genotype of an individual determines its productivity potential and the norm of reaction to environmental conditions. Genotypes of the studied gene are identified by polymerase chain reaction and restriction fragment length polymorphism (PCR-PDRP) analysis. When analyzing the data, the chi-square test is used to determine the genotype, allele frequencies and Hardy-Weinberg equilibrium. The object of research – DNA of blood of red steppe, simmental breeds of cattle of Pavlodar region of Kazakhstan. According to the results of amplification of Pit-1 gene fragment the PCR product with the size of 451 bp was obtained. According to the results of amplicon splitting the genotypes AA (451 bp), AB (451, 207, 244 bp) and BB (207, 244 bp) were obtained. In the considered farms of the region genotypes BB, AB prevail. In the studied groups of animals of the region high frequency of allele B is observed; in red steppe – 0.689, simmentals – 0.549; frequency of allele A – 0.312; 0.451 respectively. Genetic equilibrium is not disturbed; the criteria of reliability of the empirical distribution to the theoretical one in red steppe breed – 0.04, in simmentals – 0.16. The revealed associations of Pit-1 gene polymorphism can be used for selection and selecting parental pairs at directed breeding.

Improvement of the Red Steppe cattle by the Holstein breed gene pool

The results of the comparative assessment of productivity, reproductive ability and profitability of milk production when using cows of the Red Steppe breed and the crossbreeds of different blood relationship by the Holstein breed of the Red-and-White color type are presented. The studies of economically useful traits and profitability were conducted in 2019-2022. The objects of the research were representatives of the Red Steppe breed (control), mixtures with 50% (1st experimental group) and 75% of the blood of the Holstein Red-and-White color type (2nd experimental group). The superiority of the crossbred heifers over their herd mates of the Red Steppe breed in terms of milk yield was established: for the 1st lactation it was 605-673 kg (p > 0.999), for the 2nd lactation it was 714-788 kg (p > 0.999), for the 3rd lactation it was 817-868 kg (p > 0.999). The highest coefficient of the milk yield was observed in Holstein F1 and F2 crossbreeds (9.4-9.7 kg), whose average advantage during all lactations ranged from 0.9-1.2 kg (p > 0.95-0.99). In all analyzed service-periods, the highest fertilization rate after the first insemination was demonstrated by the Red Steppe breed animals; as a result, their semen consumption was on average 0.2-0.5 doses lower than that of the Holstein crossbreeds of different blood relationship. Cows of the Red Steppe breed had the highest reproductive ability coefficient 0.98-1.01 units vs. 0.85-0.95 units for crossbred cows. The analysis of the feed efficiency shows lower costs per unit production by cows of the first and second generations, in which they were 0.95-0.98 EFU, which is lower than in the Red Steppe breed peers, by 1.11-1.12 EFU. Milk production by half-blooded crossbreeds was more profitable 30.8-32.9% with no significant differences between the Red Steppe and high-blooded Holstein individuals.

Assessing Genomic Diversity and Signatures of Selection in Chinese Red Steppe Cattle Using High-Density SNP Array.

Chinese Red Steppe Cattle (CRS), a composite cattle breed, is well known for its milk production, high slaughter rate, carcass traits, and meat quality. Nowadays, it is widely bred in Jilin and Hebei Province and the Inner Mongolia Autonomous region. However, the population structure and the genetic basis of prominent characteristics of CRS are still unknown. In this study, we systematically describe their population structure, genetic diversity, and selection signature based on genotyping data from 61 CRS individuals with GGP Bovine 100 K chip. The results showed that CRS cattle had low inbreeding levels and had formed a unique genetic structure feature. Using two complementary methods (including comprehensive haplotype score and complex likelihood ratio), we identified 1291 and 1285 potentially selected genes, respectively. There were 141 genes annotated in common 106 overlapping genomic regions covered 5.62 Mb, including PLAG1, PRKG2, DGAT1, PARP10, TONSL, ADCK5, and BMP3, most of which were enriched in pathways related to muscle growth and differentiation, milk production, and lipid metabolism. This study will contribute to understanding the genetic mechanism behind artificial selection and give an extensive reference for subsequent breeding.

РЕЗУЛЬТАТЫ ПРОМЫШЛЕННОГО СКРЕЩИВАНИЯ КРАСНОГО СТЕПНОГО СКОТА С ЧИСТОПОРОДНЫМИ БЫКАМИ ГЕРЕФОРДСКОЙ ПОРОДЫ ПРИ РАЗНЫХ ТЕХНОЛОГИЯХ ПРОИЗВОДСТВА ГОВЯДИНЫ

The purpose of the research was to establish the effectiveness of breeding crossbreed bulls of the 1st generation, obtained by industrial crossing of Hereford bulls with red steppe cattle, in a comparative aspect with their red peers with different beef production technologies adopted in cattle breeding. The first control group included calves of the red steppe breed (n = 10), the second – first-generation crossbreeds from the crossing of red steppe cattle with Hereford bulls (n = 10), raised according to the dairy cattle breeding technology adopted on the farm. The first experimental group of calves was formed from animals of the red steppe breed (n = 10), the second – F1 crossbreeds (red steppe × Hereford) (n = 10). It was found that the bulls of the experimental groups by the age of 18 months had reached a live weight exceeding the values of the control groups by 59,1–73,8 kg (P > 0,999). The experimental groups of bull calves outperformed their control peers by an average of 114–135 g (P > 0,999) in terms of average daily live weight gains over the entire study period. With the same feed costs per unit of live weight gain, the largest gross increase was typical for individuals of the experimental groups. According to the main indicators of the control slaughter, the superiority was on the side of steers raised according to the beef production technology adopted in beef cattle breeding. With both cultivation technologies, the highest yield of carcass and fat was obtained from Hereford × red steppe bulls, which provided a greater slaughter yield (by 2,8–3,0 %) in comparison with peers of the red steppe breed.

MED4 gene positively affects preadipocyte differentiation in Chinese red steppe cattle

MED4 gene positively affects preadipocyte differentiation in Chinese red steppe cattle

EXTINCT FARM ANIMALS’ BREEDS OF UKRAINE

The industrialization since the beginning of the previous century led to the loss of a significant number of breeds. But it should be remembered, that the disappearance of a breed is not only the disappearance of an important unit that supplemented the uniqueness of a specific landscape, met the needs of a certain category of people who lived in this territory, performed certain rituals associated with traditions and territory, evolved with and complemented a certain culture and nation, but as well the breed – it is the genes, which were not revealed at that time, but in the future could provide people with the development of the latest technologies with new products, a new type of knowledge, skills and useful peculiarities.
 The analysis of the literal source base of the past centuries confirms the disappearance of Polish, Red Smilyan, Ukrainian White-Backed, Black-and-White Podilian in cattle breeding, in sheep breeding – 9 breeds (Walahian, Pirni, Reshetilivska, Chushka, Mazayev Merino, Malich, Hutsulian, Chuntuk), in horse breeding – Streletsky, Germano-Bessarabian, Nogai breeds and Tarpan. 3 breeding populations have disappeared in pig breeding.
 Disappeared in cattle breeding: the Polissian breed of cattle, which was widespread in the 19th and early 20th centuries on a large territory of Polissia (in 1926, on the right-bank Polissia, it numbered about 35.000 heads). By origin, the Polissian cattle were admitted a descendant of the ancient race that lived in Polissia since ancient times.
 The animals were exceptionally hardy, resistant to diseases typical for the region, and had a certain productivity even in difficult conditions of unsatisfactory keeping.
 The Red Smilyan breed of the beginning of the 20th century was spread in the area of the town of Smila, "from north to south along the railway through the town of Smila all the way to Horodyshche and Chhyrynsky district. This breed was "a branch of red steppe cattle, which, like Grey Ukrainian cattle, belonged to the group of steppe cattle." So, it would be interesting to investigate it as well.
 At the beginning of the last century, the different varieties of spotted cattle of Podillia were spread over almost the entire territory of the Vinnytsia region (except for the northern part). Researchers estimate the presence of this livestock at the level of 100.000 heads at the beginning of the last century. This group included Black-and-White Podilian and Ukrainian White-Backed breeds.
 Sheep breeding. Coarse-wool sheep have been bred on the territory of Ukraine for a long time, especially Reshetilivska and Sokilian sheep. In the literature, there is also information about the breeding of Wallahian sheep.
 Horse breeding. Research in recent years suggests a high probability of domestication of horses in the territory of the steppes of Ukraine, so it would be especially interesting to study the behavior, characteristics, and variety of products of ancient horses of Ukrainian origin. However, this is no longer possible on at least 3 breeds of horses: Striletska, Germano-Bessarabian, Nogai and Tarpan. In addition, there is evidence that in Ukraine in the 17th century a breed of striped (tarantoid) horses was widespread. Ethnological studies also report on the existence of Steppe Ukrainian horse, bred in Zaporizhzhia, and Boykivian (boyki, perevinniki) horse breed in the Carpathians. The Ukrainian breed of horses became the basis for the formation of the Black Sea breed in the Kuban after the Cossacks of Zaporizhzhya Sich were resettled there in the 19th century.
 Pig breeding. According to the National Coordinator of Genetic Resources from Ukraine in FAO until 2014, I.V. Guzev, three breed groups of pigs and one local population (European short-eared pig) have disappeared in Ukraine. According to ethnographers, Ukrainian black and brown breeds have long been predominant on the territory of Ukraine. So, it was the Ukrainian sub-population of European group of pigs. This group as well was characterized with yellowish, brown or white, mixed with black bristle color. There were as well individuals of gray or white color with black spots, small fangs were visible.

RNA-Seq Analysis Identifies Differentially Expressed Genes in the Longissimus dorsi of Wagyu and Chinese Red Steppe Cattle.

Meat quality has a close relationship with fat and connective tissue; therefore, screening and identifying functional genes related to lipid metabolism is essential for the production of high-grade beef. The transcriptomes of the Longissimus dorsi muscle in Wagyu and Chinese Red Steppe cattle, breeds with significant differences in meat quality and intramuscular fat deposition, were analyzed using RNA-seq to screen for candidate genes associated with beef quality traits. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that the 388 differentially expressed genes (DEGs) were involved in biological processes such as short-chain fatty acid metabolism, regulation of fatty acid transport and the peroxisome proliferator-activated receptor (PPAR) signaling pathway. In addition, crystallin alpha B (CRYAB), ankyrin repeat domain 2 (ANKRD2), aldehyde dehydrogenase 9 family member A1 (ALDH9A1) and enoyl-CoA hydratase and 3-hydroxyacyl CoA dehydrogenase (EHHADH) were investigated for their effects on intracellular triglyceride and fatty acid content and their regulatory effects on genes in lipogenesis and fatty acid metabolism pathways. This study generated a dataset from transcriptome profiling of two cattle breeds, with differing capacities for fat-deposition in the muscle, and revealed molecular evidence that CRYAB, ANKRD2, ALDH9A1 and EHHADH are related to fat metabolism in bovine fetal fibroblasts (BFFs). The results provide potential functional genes for maker-assisted selection and molecular breeding to improve meat quality traits in beef cattle.

Absorption of dry matter, crude ash, and crude fat in the gastrointestinal tract of bugai at different amounts of soluble protein in the diets

In red steppe cattle with duodenal and ileocecal anastomoses when fed isoenergetic, isoprotein hay-concentrate rations with different levels of soluble protein (SR), the digestibility of dry matter (SR), crude ash (CW) and crude fat (CW) was studied separately in a complex stomach , small (TnK) and large (TsK) intestinal sections. Different amounts of RchSP in the rations were achieved by feeding grist from natural and roasted peas at a temperature of 105°C.
 When feeding the experimental ration with a reduced level of RchSP against the background of a decrease in the apparent intensity of digestion, which was manifested in a smaller amount of duodenal and ileocecal chyme, significant changes in the digestibility of SR, SZ and SZ were observed in the postruminal sections of the gastrointestinal tract. According to the general digestibility of SR in the entire alimentary canal and prestomach, in the small and large intestines, there were different directions and degrees of changes in the experimental and control diets. The digestibility of SZ, while being the same in the entire alimentary canal, differed most significantly between rations in the complex stomach and TsK, less so in TnK. On the experimental diet, absorption of dietary fiber in the small and large intestines was 18% lower. The actual level of digestibility of dietary fiber in the animal body did not correspond to the value determined by the formula "feed minus feces" and was 2 times higher in the control diet and 1.4 times higher in the experimental diet.
 The assimilation of dietary fiber in the studied rations in the alimentary canal had a multidirectional character and, in general, was lower in the experimental ration. The actual digestibility of dietary fiber, compared to the "visible" digestibility of the control diet, was 17% higher, and the experimental diet was 3% lower.

Dependence of milk productivity of red steppe cows on balanced diets

Today, livestock farming is characterized by intensive development, rapid adoption of technology and an active increase in animal productivity. The genetic potential of dairy cattle allows for increased milk production, but feed remains a limiting factor. High cow productivity, increased reproductive capacity, and long-term economic feed use can only be achieved with a complete, balanced diet containing all-sufficient nutrients. The research was conducted at a breeding farm for red steppe cattle of the Azovskoye CJSC, Azovskoye District, Omsk Region. The dairy productivity of cows is determined by the quality of their feed and the adequacy of their nutrition. Rumen and postrumen digestion, feed intake, productivity, and cattle health depend on the ruminant’s diet value. The total content of nutrients, macro-and micro-nutrients, vitamins and amino acids in the feed is determined to assess the nutritional value of the feed. Equally important are the physical properties of the meal. When formulating diets for high-yielding cows, the main parameters to consider are particle size, particle length of feed raw material or feed fragments, and the amount of bulk grass feed. At the Azovskoye farm, feeding is done from the Hostin feeder-mixer three times a day. Dairy cows are fed large quantities of bulky fodder, which is a rich source of fibre, which accounts for the structural value of the ration. Milk production increases every year. In 2019, for example, 6,747.3 tonnes of milk were produced, increasing 248.9 tonnes compared to 2018. High productivity, reproductive capacity and the longevity of economic use of breeding cows can only be achieved with nutritionally balanced feed.

ВЛИЯНИЕ ИНТЕНСИВНОГО ВЫРАЩИВАНИЯ ТЕЛОК НА ИХ РОСТ И ПРОДУКТИВНОСТЬ

As a result of research aimed at improving the red steppe cattle, using the gene pool of Ayrshire and Holstein Red-and-White cattle, it was found that the resulting crossbreeds were distinguished by higher milk productivity. When studying the livestock, groups of animals with higher productivity rates were identified and formed in comparison with the average for the herd. Crossbred heifers of the first generation were intensively grown and inseminated at the age of 13-15 months when they reached a live weight of 360-380 kg. The effect of heterosis contributed to obtaining such a live weight. The average daily gain in live weight varied from 861 to 900 grams, both for individual age periods and for the entire growing period, the tendency for the superiority of crossbred heifers remained. In terms of milk productivity, crossbred Holstein Red-and-White heifers surpass their peers of purebred red steppe heifers in terms of milk yield by 586,8 kg or 11,3% (P>0,99), in terms of fat content they exceeded by 0,22% (P>0,99) and protein – 0,05% (P>0,99). Crossbred Ayrshire heifers of group II yielded in terms of milk yield to peers of group III by 76 kg, but in terms of fat content they were superior by 0,06, protein 0,15%. The amount of milk fat in the milk of cows II and III was at the same level of 214,8-214,9 kg and exceeded the purebred peers of group I by 34,2-34,3 kg (P>0,99), and the amount of milk protein – 16,2-21,6 kg (P>0,95).

A Study on the Dynamics of the Development of Red Steppe Cows and Their Ayrshire and Holstein Crossbreeds

When purchasing animals from abroad, agricultural enterprises often underestimate their demand for feed quality and feeding standards for ensuring genetically determined milk productivity. Therefore, increasing attention should be paid to raising local breeds. During the creation of new production relations, it is very important to preserve achievements of scientists and breeders. The widespread use of red steppe cows is due to good feed payment, unpretentiousness, and their adaptability to the steppe zone with its arid climate. There was a real threat of extinction of purebred red steppe cattle: with the intensification of dairy cattle breeding, as well as low milk productivity, these animals are inferior to the best dairy breeds by productivity, but they are better by endurance, resistance to diseases, and adaptability to extreme environmental conditions. Therefore, scientific research is needed on improving the productive and technological qualities of this breed using the best global gene pool of dairy cattle. This article presents the results of a study on the development of heifers of purebred red steppe cows and their Ayrshire and red-motley Holstein crossbreeds. Differences in the live weight indicators of the purebred and crossbred heifers were due to the effect of crossbreeding and intensive growing technology, which made it possible to maximize the genetic potential of the crossbred animals.
 Keywords: breed, steppe red, Holstein, Ayrshire, live weight, feed costs, diet

Technology for increasing calf yield using ultrafine particles of silicon dioxide

The technology provides for the intramuscular injection of ultrafine particles of silicon dioxide during the synchronization of sexual heat at a dose of 10 μg/kg to increase the yield of offspring. The experiment involved the Red Steppe cattle. There were two groups of 10 cows exposed to estrous synchronization with oestrophan. In the experimental group, the animals were injected with a solution of SiO2 nanoparticles simultaneously with the second injection of oestrophan. All cows were inseminated artificially. In the experimental group, the fertilization rate was 70.0 %, while in the control group – 60 %. FSH and LH dynamics in the blood serum in both groups was similar, but in the experimental group, the level of hormones during an induced estrous cycle changed more dramatically.

Milk productivity of modern red steppe cattle in the Omsk region

Milk productivity of modern red steppe cattle in the Omsk region

The influence of the foundation stock (the improving breed) on the phenotypic characteristics of the red steppe cattle

The influence of the foundation stock (the improving breed) on the phenotypic characteristics of the red steppe cattle

The effectiveness of crossing Red steppe cattle with Anglers in order to increase the meat productivity of crossbreeds

The article highlights the results of scientific experience in studying the meat productivity of cross-breeding red steppe bulls with genotypes 1/2,3/4 and 7/8 in Angler breed in comparison with pure-bred red steppe bulls. In the course of a complex of scientific research and chemical analyzes, it was found that thanks to the use of Angler breed, it is possible to obtain highly productive young cattle that are superior in quantitative and qualitative indicators of productivity to pure-bred red steppe cattle.

Fertility and Productive Performance of Cattle at Different Levels of Atmospheric Pressure

The objective of the surveys was to study fertility and productive performance of heifers and cows of the Red Steppe breed under different atmospheric pressure gradients of 725–750, 751–775, 774 mm Hg, and higher pressure gradients. On the days with the indicated atmospheric gradient frontiers, the heifer and cow insemination and milk yield control procedures with the analysis of the milk chemical composition were performed. It was ascertained that both cows and heifers demonstrated the highest conception rates at the first insemination (61.1 and 58%, respectively) on the days with the atmospheric pressure of 751–755 mm Hg. The maximum percentage of dry cows was registered during insemination of the animals on the indicated days. The highest daily milk yields were recorded in cows on the days of lactation, when the atmospheric pressure gradient did not exceed 775 mm Hg. Predominance of milk production over the milk yield obtained in the periods with the maximum atmospheric pressure comprised 3.1–3.6 kg (P > 0.99–0.999). The same trend could be observed in the dry matter content and the basic milk components. The survey outcomes show that conception rates and productive performance of the Red Steppe cattle are characterized by maximum values under the atmospheric pressure gradients (751–775 mm Hg) considered comfortable and suitable for animals.

The effect of Acot2 overexpression or downregulation on the preadipocyte differentiation in Chinese Red Steppe cattle

ABSTRACT The quality and nutritional value of beef is closely linked to its content of intramuscular fat (IMF). The differentiation of preadipocytes and the deposition of lipid droplets in the adipocytes are the key to regulate the IMF content. The differentiation of adipocytes is regulated by a series of transcription factors and genes. Acyl-CoA thioesterase 2 (Acot2) hydrolyzes the acyl-coenzyme A (CoA) into free fatty acids and CoA and has the potential to maintain the free fatty acids and acyl CoA at the cellular level. In this work, we detected the expression of the Acot2 gene during the adipocyte differentiation in Chinese Red Steppe cattle, and then interfered and overexpressed the Acot2 gene in the preadipocytes to explore its regulatory role in the adipocyte differentiation. The results showed that the expression and regulation of Acot2 mainly occurred at the later stage of the adipocyte differentiation. The interference with the Acot2 gene significantly inhibited the lipid droplets accumulation and triglyceride content, while its overexpression significantly promoted both of them. The results of this study show that the Acot2 gene is a positive regulator of the adipocyte differentiation and may become a new target to improve the beef quality.

Effect of ACSL3 Expression Levels on Preadipocyte Differentiation in Chinese Red Steppe Cattle

Domestic cattle are an important type of livestock, with beef production playing a major role in the agricultural economy. Adipocyte levels and fat content are interrelated, with meat quality being highly dependent on its fat content and distribution. Acyl-CoA synthetases of long-chain (ACSL) fatty acids (FAs) play an integral role in virtually every metabolic pathway in mammalian biochemistry, including complex lipid biosynthesis, protein modification, and β-oxidation processes. ACSL3 activity is also known to be associated with adipocyte differentiation; however, its biological mechanism of action is currently unclear. Gene expression in subcutaneous preadipocytes isolated from subcutaneous deposits of Chinese Red Steppe cattle has been studied using in vitro cell transfection, real-time polymerase chain reaction and western blot analysis. The lipid and triglyceride contents of lipid droplets have also been measured to verify the levels of gene expression. These combined studies show that ACSL3 is induced during adipocyte differentiation, with its overexpression promoting an increase in the triglyceride content of lipid droplets. Furthermore, mRNA and protein expression levels for adipocyte differentiation marker genes, such as peroxisome proliferator-activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha (C/EBPα), were markedly increased during mature adipocyte cell differentiation. Knockdown of ACSL3 expression using ACSL3 small interfering RNAs (siRNAs) resulted in a decrease in lipid content of cattle adipocytes, providing further evidence that ACSL3 plays a key role in the differentiation process.