Lactation Period In Cows Research Articles

Identification of the polymorphism of the <i>APAF1</i> gene and its association with economically useful traits of Holstein cattle

A decrease in the reproductive ability of cows leads to losses in dairy farming, as dairy production decreases due to the lack of a lactation period in cows. Haplotype HH1 is responsible for a mutation in the protein apoptotic protease-activating factor 1 (APAF1), as a result of which its structure is shortened, resulting in a decrease in fertility, an increase in the number of embryonic mortality and abortions in Holstein dairy cattle. To study the polymorphism of the APAF1 gene (SNP p.Q579X [c.1741C>T]) and its associations with economically traits, we used data and DNA from 254 cows of Holstein population of indigenous selection of Breeding Farm Integrated Agricultural Production Center of the Republic of Tatarstan. As a result, 2 alleles (Q and X) and 2 genotypes (QQ and QX) were identified in the APAF1 – BstC8 I gene locus in cattle. It was established that the dominant population is represented by carriers of the homozygous QQ genotype of the APAF1 gene - 98.0 %, and the frequency of the Q allele reached 0.990. The percentage of QX-type animals is minimal - 2.0 % of the total number of cows subjected to the study, as a result of which the occurrence of the X allele was only 0.010. An assessment of the influence of APAF1 gene polymorphism on economically significant traits showed that, depending on the genotype, such reproduction traits as the age of the first fertile insemination, the duration of the dry period and the Doha fertility index vary statistically significantly. Analysis of dairy productivity traits that cows with the QQ genotype are significantly superior to individuals with the QX genotype in all compared positions, with the exception of the content of the mass fraction of fat. Through selection using genetic marking, damage to livestock farms can be reduced by reducing the frequency of carriers of lethal alleles in the parent generation. This research was supported by FASO Russia project, registration number 122011800138-7.

The Concentrations of Selective Endocrine Disruptors in Milk from Different Lactation Periods of Cows

The Concentrations of Selective Endocrine Disruptors in Milk from Different Lactation Periods of Cows

A comparison of the milk yield and morphometrics of Irtysh type Simmental cows and their Holstein and Simmental crosses in East Kazakhstan

Abstract. Nusupov AM, Sambetbaev AA, Kozhebaev BZ, Nurzhanova KH, Gorelik OV. 2021. A comparison of the milk yield and morphometrics of Irtysh type Simmental cows and their Holstein and Simmental crosses in East Kazakhstan. Biodiversitas 22: 3663-3670. Cattle breeding is still a significant part of agriculture manufacture both in milk and beef production. Dairy manufacture needs more and more modifications to increase milk productivity and produce milk with better nutrition properties. The authors present a comparison of the dairy cattle of the Simmental breed (Kazakhstan Irtysh type) and its cross-breeds with red-piebald Holstein and Simmental breeds. All the animals' breeds were studied at the time of the first lactation period in cows at the “Kamyshinskoye” farm, Shemonaikha District, East Kazakhstan region. We studied the milk productivity, exterior parameters, and reproductive indicators for the control animal group (Simmental breed Irtysh type) and the crosses (cross-breeds) of the red-piebald Holstein when collecting the research results and Irtysh type and Simmental and Irtysh type. All data obtained in this study have been fully compared with the indicators of the first lactation period of Simmental cows of the Irtysh type. As a result of the study, authors have created the curve of the 305-day lactation period, studied the exterior of the animals, the morphological structures of the udder, and the annual capacity cycles of the tested cows' group. The milk yield obtained in the first complete lactation period from the red-piebald Holstein cross-animals was 240 kg or 4.2% more than the control mother group, but the average milk fat percentage has been 0.09% less. On the contrary, the cross of the Irtysh and Simmental breed has a yield less by 258 kg or 4.7% (5277 kg), but a fat milk percentage has been 0.1% more.

МОЛОЧНАЯ ПРОДУКТИВНОСТЬ КОРОВ ПРИ ИСПОЛЬЗОВАНИИ В РАЦИОНАХ БЕЛКОВОЙ ДОБАВКИ «БЕЛКОФФ-М»

The disclosure of the genetic potential and milk productivity of cows of the Holsteinized Black-and-White breed largely depends on the use of certain feeding factors. The lack of protein and the imbalance of its quality indicators, the lack of amino acids in diets is one of the most important problems in feeding dairy cattle in modern animal husbandry. The synthesis of microbial protein in the rumen is limited and provides only up to 50% of the cows' protein needs, the remaining 50% must be supplied to the animal's body with protein that is not degradable in the rumen. But, since traditional feeds have a low content of it, it is necessary to enrich the main diet with high-protein supplements. To solve this problem, we used the method of introducing into the diet of cows of the experimental group an additive with a "protected" protein - "Belkoff-M". The study was conducted on the basis of the dairy complex LLC "Modern Agrotechnologies" "Ryzhovo" of the Moscow region, Podolsky district, the village of Babenki. 20 dairy cows of the Holsteinized Black-and-White breed were selected by the method of pair-analogues, taking into account the breed, age, live weight, productivity and date of the last calving. Animals received the same diet in the preliminary period. By the beginning of the experiment, the lactation period of cows ranged from 123 to 215 days. Then they were divided into two groups, one of which received a protein supplement instead of part of the feed. The results in the groups were determined in accordance with the data of control milkings and chemical analysis of milk on the 19th, 47th and 76th day of the experiment. Studies have shown the effectiveness of the protein supplement "Belkoff-M" in feeding highly productive cows. Was reduced part of the feed in the diet and increased the amount of non-degradable protein in the rumen. Thus, it was possible to reduce the exorbitant level of cleavable protein, which ultimately led to the normalization of metabolic processes in the animal body and an increase in the productivity of cows.

Protective effect of chitosan oligosaccharide against oxidative damage of peripheral blood mononuclear cells in dairy cows induced by diethylenetriamine/nitric oxide via NF-κB signalling pathway

Excessive production of nitric oxide (NO) during the lactation period of cows leads to oxidative stress and inflammatory reactions. Chitosan has enhanced effects on antioxidant and immune function, but the mechanism of this effect is unclear. The current study investigated the underlying mechanism of the protective effect chitosan oligosaccharides (COS) exert against oxidative damage of peripheral blood mononuclear cells (PBMCs) in dairy cows. PBMCs were allocated to receive one of treatments: CTR: control treatment without COS addition; COS40, COS80, COS160, and COS320 received 40, 80, 160, and 320 μg/mL of COS; PBMCs were then treated with 200 μmol/L diethylenetriamine/nitric oxide (DETA/NO) for 4 h. Compared to the CTR group, the cell viability of the COS pre-treated group increased with increasing COS concentration. The activities of antioxidant enzymes including superoxide dismutase, catalase, and glutathione peroxidase and the thioredoxin reductase content showed an upward trend in a dose-dependent manner and COS at a concentration of 160 μg/mL exhibited the strongest effect. COS decreased the content and gene expressions of interleukin-1β and tumour necrosis factor-α, the mRNA and protein expression and activity of the inducible nitric oxide synthase, and NO production compared with the values observed in the CTR group. The expression of genes and proteins related to the nuclear factor kappa-B (NF-κB) pathway also showed a downward trend. Based on these indicators, we concluded COS has a protective effect against oxidative damage caused by DETA/NO, and we speculated that COS may play a protective role by inhibiting the NF-κB pathway. Highlights In vitro experiments simulated changes in antioxidant and immune functions caused by increased NO in dairy cows’ PBMCs in vivo. We showed that chitosan has a protective effect against oxidative damage and a regulatory effect on immune function in vitro. The regulation of chitosan against oxidative stress and immune responses may be related to the NF-KB signalling pathway.

Effect of postpartum administration of ketoprofen on proinflammatory cytokine concentration and their correlation with lipogenesis and ketogenesis in Holstein dairy cows.

Early lactation period in dairy cows could be harmful to their health since it is challenging and demanding. Proinflammatory cytokine concentrations are increased in the early phase of the inflammatory response and during the early lactation period in cows. The aim of this study was to determine if ketoprofen treatment in the first days following parturition would decrease proinflammatory cytokine concentration and their correlation between lipid mobilization, ketogenesis and metabolic parameters in cows. The study was conducted on 30 cows divided into two groups of 15 cows each. The experimental group was treated with 3 mg × kg.bw.-1 ketoprofen for three consecutive days after parturition. The blood samples were collected on the first day of treatment and in the first and second week postpartum and they were analyzed for biochemical parameters such as non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHBA), glucose, cholesterol and total bilirubine and inflammatory parameters such as tumour necrosis factor-α (TNF-α), interleukin-1α (IL-1α) and interferon-γ (IFN-γ). The results suggested that ketoprofen- treated cows had a significantly lower concentration of TNF-α, IL-1α, IFN-γ, NEFA and BHBA in the first and second postpartum week compared to the control group. Ketoprofen administration increased glucose levels (the first week, p⟨0.05), increased cholesterol levels (the second week, p⟨0.01) and decreased serum total bilirubin levels (second week, p⟨0.01) compared to the control group of cows. A positive correlation was found between TNF-α and NEFA and total bilirubin, significantly more expressed in the control than in experimental group of cows (p⟨0.01) and it was also found between IL-1α and NEFA (p⟨0.01). A negative correlation was found between TNF-α and glucose and cholesterol, significantly more expressed in the control than in experimental group of cows (p⟨0.01). A positive correlation was also found between IL-1α and glucose (p⟨0.01). Ketoprofen given parenterally to Holstein cows immediately after calving could reduce inflammation and decrease the relation between inflammatory response and lipogenesis and ketogenesis in postpartum cows.

<b>Body size and its effects on productive efficiency of cows with predominant Nellore genetic composition

This study was developed to evaluate productive efficiency during the lactation period of cows with predominant Nellore genetic composition based on their body size. Cows were divided into the following categories: light (≤ 316 kg), moderate (≥ 317 and ≤ 400 kg), or heavy (≥ 401 kg). Body weight change and total gain from birth to 210 days of age of calves born from heavy cows (0.155±0.03 and 111.6±5.1 kg) were higher than those of calves born from light (0.064±0.03 and 91.0±4.3 kg) and moderate (0.144±0.03 and 97.7±4.0 kg) cows. Calf production index differed (p < 0.05) with the herd of heavy cows (93.5±3.2 kg), producing 57.4 and 19.7% more kilograms of calf than light (59.4±2.7 kg) and moderate (78.1±2.4 kg) cows, respectively. Heavy Nellore cows produce heavier calves and have a better reproductive performance, which lead to a better calf production index. However, they require a larger area for the same herbage allowance. Calves born from heavier Nellore cows gain more weight from birth to 210 days of age and are heavier from 210 to 270 days of age.

PRODUCTIVE QUALITIES OF ANIMALS OF DIFFERENT BREEDS OF CATTLE

Increasing the number and improving the quality of milk and meat are the main goal and main focus of cattle breeding. The purpose of our research was to study milk and meat productivity of animals of different breeds which are bred in Western Ukraine.
 The researches were conducted at eight farms in Western Ukraine with cows and bulls of Ukrainian Black-and-White Dairy, Ukrainian Red-and-White Dairy Red, Ayrshire, Red Polish, Simmental, Carpathian Brown, Limousin and Volyn Beef breeds.
 Evaluation of milk production of cows of dairy and dual-purpose breeds (yield, fat content in milk, the amount of milk fat) was carried out according to the data of zootechnical accounting (during the past 20 years) for the I, II, III, IV, V and the best lactation. The chemical composition of milk was determined in 2-3 months of lactation period in cows of full-age (the III lactation) for each breed using milk analyzer "EKOMILK TOTAL".
 Researches of meat quality were conducted based on a control slaughter of 3 bulls at the age of 15 months for each breed. Live weight before slaughter was determined after a 24-hour hunger exposure. Weight of pair carcasses, internal fat weight, slaughter weight, carcass yield, the output of internal fat, and slaughter output were determined after slaughter by G. T. Shkuryn method. Weights of flesh, bones and tendons were determined in the semi-carcasses. Ratio of meatiness, calculated as the ratio of flesh to bones and tendons, and muscle-bone ratio, calculated by dividing flesh weight to weight of bones, were determined to assess meat quality. Average sample of mincemeat from three ribs cuts was selected for the chemical analysis. The samples were tested on contents of moisture, dry matter and ash by conventional techniques, of protein content – by Kjeldahl method, fat content – by Soxhlet method.
 The results of the researches were processed by method of variational statistics using Microsoft Excel and "Statistica 6.1" by N. A. Plohynskiy.
 It was established that cows of the studied breeds differed in terms of milk production; it is primarily due to the fact that some of them belong to the specialized breeds, others – to local (less productive). However, all of them by milk yield, fat content in milk and the butterfat number prevailed relevant standards of these breeds (exception – fat content in milk during the first lactation of the Ayrshire cows). Highest milk yield was observed during the third lactation at the most animals of the studied breeds and only for Ukrainian Red-and-White Dairy and Simmental breeds – during the fourth lactation. Milk yield of Ukrainian Black-and-White Dairy cattle, depending on lactation was within 3970.9-4537.9 kg, fat content in milk – within 3.67-3.71% and the number of milk fat – within 149.5 -168.0 kg; Ukrainian Red-and-White Dairy – in accordance within 3503.0-4471.8; 3.76-3.78 and 132.4-168.6; Red Polish – within 2838.4-3698.4; 3.70-3.73 and 107.9-138.6; Ayrshire – within 4034.3-4337.0; 4.0-4.12 and 165.4-181.7; Simmental – within 3026.4-3810.2; 3.76-3.81 and 113.6-145.0 and Carpathian Brown breed – within 2700.5-3384.4 kg; 3.69-3.85% and 99.8-125.9 kg.
 The results of the control slaughter indicated that the bulls of the studied breeds differed in slaughter qualities and morphological composition of carcasses. The Ukrainian Red-and-White Dairy bulls among dairy breeds were characterized by the highest slaughter output (55.2%) and carcass yield (56.7%), the Simmental bulls (58.1 and 59.7% respectively) – among the dual-purpose breeds, and the Limousins (63.2 and 61.4%) – among the beef breeds. The highest percentage of flesh was observed at the semi-carcasses of these animals. Higher contents of protein and fat in meat of the Polish Red bulls were observed among the dairy breeds and in meat of the Simmentals – among the dual-purpose ones. Higher protein content was in meat of the Limousins among the beef breeds and fat content – at the animals of Volyn Beef breed.
 Ratio of meatiness at the animals of the dairy breeds was within 3.18-3.27, muscle-bone ratio – within 3.83-4.00, these figures were 3,38-3,51 and 4,15-4,33 respectively at the bulls of the dual-purpose breeds, and for the beef breeds – 6,42-6,78 and 6,26-6,59.

Lactogenic hormones alter cellular and extracellular microRNA expression in bovine mammary epithelial cellculture.

BackgroundBovine milk contains not only a variety of nutritional ingredients but also microRNAs (miRNAs) that are thought to be secreted by the bovine mammary epithelial cells (BMECs). The objective of this study was to elucidate the production of milk-related miRNAs in BMECs under the influence of lactogenic hormones.ResultsAccording to a microarray result of milk exosomal miRNAs prior to cellular analyses, a total of 257 miRNAs were detected in a Holstein cow milk. Of these, 18 major miRNAs of interest in the milk were selected for an expression analysis in BMEC culture that was treated with or without dexamethasone, insulin, and prolactin (DIP) to induce a lactogenic differentiation. Quantitative polymerase chain reaction (qPCR) results showed that the expressions of miR-21–5p (P = 0.005), miR-26a (P = 0.016), and miR-320a (P = 0.011) were lower in the DIP-treated cells than in the untreated cells. In contrast, the expression of miR-339a (P = 0.017) in the cell culture medium were lower in the DIP-treated culture than in the untreated culture. Intriguingly, the miR-148a expression in cell culture medium was elevated by DIP treatment of BMEC culture (P = 0.018). The medium-to-cell expression ratios of miR-103 (P = 0.025), miR-148a (P < 0.001), and miR-223 (P = 0.013) were elevated in the DIP-treated BMECs, suggesting that the lactogenic differentiation-induced secretion of these three miRNAs in BMECs. A bioinformatic analysis showed that the miRNAs down-regulated in the BMECs were associated with the suppression of genes related to transcriptional regulation, protein phosphorylation, and tube development.ConclusionThe results suggest that the miRNAs changed by lactogenic hormones are associated with milk protein synthesis, and mammary gland development and maturation. The elevated miR-148a level in DIP-treated BMECs may be associated with its increase in milk during the lactation period of cows.

Temporal changes in plasma concentrations of hormones and metabolites in pasture-fed dairy cows during extended lactation

This experiment measured variations in plasma concentrations of metabolic hormones and metabolites in cows undergoing extended lactations of up to 670 d at 2 planes of nutrition. Thirty-seven Holstein-Friesian cows that calved in late winter were selected for varying milk yield and then managed for a lactation of 670 d by delaying breeding until approximately 450 d in milk (DIM). Cows grazed fresh pasture supplemented with pasture silage or hay and crushed wheat or triticale grain. Dietary intake was reduced by approximately 1.8kg (dry matter) grain/cow per day for 19 of the cows from 300 DIM until the end of lactation to assess the effect of restricted energy intake on the persistency of milk production. Samples of blood were collected monthly from each cow to measure plasma concentrations of selected hormones and metabolites. Dietary restriction beyond 300 DIM reduced yields of milk, protein, and fat, but did not alter the proportion of cows reaching the 670-d lactation target. Dietary restriction had no effect on cow BW or plasma concentrations of any hormones or metabolites. Overall, blood plasma concentrations of insulin-like growth factor-I, leptin, and glucose were elevated from 301 to 600 DIM compared with 0 to 300 DIM, whereas concentrations of growth hormone and nonesterified fatty acids were lower after 300 DIM. Plasma concentrations of insulin and prolactin were unaffected by stage of lactation, but prolactin concentrations increased during summer. These changes were consistent with a decrease in milk yield and an increase in the partitioning of nutrients to body tissue gain, primarily adipose tissue, throughout the later stages of the extended lactation. Cows that continued milking beyond 600 DIM had increased plasma concentrations of growth hormone and decreased concentrations of glucose and leptin compared with cows that milked <600 DIM. These differences, coupled with reduced body weight gain, indicated an increased priority for nutrient partitioning to milk production at the expense of body tissue gain throughout the extended lactation period in cows with greater lactation persistency.

Kinetics of anti-Fasciola IgG antibodies in serum and milk from dairy cows during lactation, and in serum from calves after feeding colostrum from infected dams

A study was carried out to compare anti- Fasciola hepatica IgG levels in blood serum and mammary secretions during the entire lactation period in dairy cows experimentally infected with different numbers of F. hepatica metacercariae. The kinetics of specific antibodies passively transferred to the offspring was also studied. The MM3-SERO ELISA, a specific and sensitive method of detecting antibodies against F. hepatica, was used to detect antibodies in milk and serum samples. The progress of infection was monitored by use of the MM3-COPRO ELISA, an immunoassay for detecting Fasciola antigens in faecal samples. The optical density of serum and milk from uninfected control cows remained low throughout the study. In the infected animals, a similar pattern of anti- F. hepatica IgG kinetics was observed in serum and milk throughout the entire observation period. This IgG response was characterized by the early appearance of high levels of specific antibodies in serum (detectable 1–4 weeks pi) and in milk (detectable at the beginning of lactation) and remained invariably high throughout the entire lactation period in cows infected with low-to-moderate infective doses (≥50 metacercariae). However, in animals administered very low infective doses (≤25 metacercariae) the levels of specific antibodies were variable, and would be difficult to interpret if only sporadic analyses were carried out. The MM3-SERO ELISA proved to be highly sensitive for use with milk samples, as it enabled detection of antibodies in cows infected with very low infective doses (≤25 metacercariae) and therefore harbouring very few flukes (probably < 10). Moreover, specific antibodies were able to be detected at any stage of lactation, in milk from cows infected with ≥50 metacercariae, even when samples were diluted al least 1:8. In newborn calves fed colostrum from infected dams, the levels of anti- Fasciola antibodies increased rapidly, then decreased sharply and were no longer detected in calves >12 weeks old. The results indicate that the detection of antibodies in milk samples may provide useful information about the status of F. hepatica infection in dairy herds if repeated analyses are carried out. Analysis of bulk samples may also be an inexpensive way of identifying herds infected with F. hepatica, provided highly sensitive tests are used.

A bivariate gamma mixture distribution

In this paper we construct a bivariate gamma mixture distribution by allowing the scale parameters of the two marginals to have a generalized Bernoulli distribution. We study the statistical properties of this distribution and discuss the estimation of the parameters. The distribution is then fitted to two bivariate data sets. Data on the age and lactation period of cows are described well by the proposed model, but it fails to fit Johansen's bean data properly because of theoretical constraints on the correlation.

The Effect of Environmental Temperature on the Percentage of Fat in Cow's Milk

The great variation in the composition of cow's milk is a matter of common observation. Studies of the causes of this variation, with regard to the fat content of milk, are numerous and have been summarized by Turner (30), who states that there are two fundamental causes of the variations. The first is the hereditary variation due to the genetic makeup of the breed and individual. The second cause appears to be due to physiological changes in the animal, caused by such factors as management, environment, lactation, reproduction and age. To the second cause Woodward (33) and Clothier (11) would add feed as a factor, and Eckles (12) adds the factor of condition of cow at time of calving. The effect of environment, or more specifically, environmental temperature, is considered in this paper. The relation between season of the year and the per cent of fat in milk is generally known. • It was shown by Eckles (13) in 1909 from a study of 240 lactation periods of cows in the Missouri and Iowa Experiment Station herds. He found that, regardless of when the lactation began, the percentage of fat when plotted followed a curve for the year, being lowest during June and July and gradually rising to the highest point in December and January, and then declining again till midsummer. White and Judkins (32) concur in this opinion, presenting data taken on 49 cows over a period of seven and one-half years. They conclude that the milk tests lower in fat content in the