Improve Milk Quality Research Articles

The quality of meat in milk fed lambs is affected by the ewe diet: A review

Several scientific publications have highlighted the importance of feeding management practices in improving the nutritional properties of milk from dairy ewes. Meat production quality from suckling lambs is based on the use of milk as exclusive or near exclusive dietary component. There is considerable evidence that lamb meat contains many important nutrients and bioactive compounds that play an important role in consumer health. This paper examines the different quality characteristics of lamb meat from ewes fed different diets to improve milk quality. To conduct this research, we consulted different scientific databases and acquired relevant documents that studied the relationships between the dietary treatment of lactating ewes and the performance of their suckling lambs (growth and carcass traits) as well as the meat quality in terms of nutrient content (fat and protein in particular), bioactive compounds content (fatty acids, vitamins, and antioxidant molecules), color, odor and flavor. The extent of change in meat carcass traits and meat quality of suckling lambs due to different feeding strategies applied to ewes was evaluated and discussed. This overview of the knowledge on the relationship between the milk quality and suckling lamb quality can be useful for production and communication strategies development for the lamb meat industry.

Effect of bovine subclinical mastitis on milk production and economic performance of Brazilian dairy farms

This review summarized the significant results from Brazilian studies published in peer-reviewed scientific papers about the effect of bovine subclinical mastitis (SM) on economic performance and milk production. Different approaches were considered for (i) disease detection (indirect measurement of somatic cell count (SCC) and directly using microbiological culture) and (ii) milk sampling strategy (mammary quarters, composite cow samples, and bulk milk tank). Globally, bovine mastitis is the most common disease of dairy herds, and the subclinical presentation is the most frequent. Dairy farmers usually underestimate the economic losses associated with SM because no visual changes in milk and quarters, udder, and systemic symptoms are observed. SM reduces milk yield and quality, reducing dairy herds’ profitability. The estimation of losses depends on the causative pathogen, the lactation stage, and the parity of affected cows. Thus, estimating the economic caused by SM in milk production and economic performance in dairy herds can be used to decide which mastitis control strategies to adopt. Mastitis control involves adopting specific measures associated with the characteristics of each herd, the period of the highest frequency of cases, the transmission form, and the profile of the pathogens involved in cases of intramammary infection. Thus, using individual SCC, the microbiological identification of pathogens causing SM, adopting efficient drying-off protocols, and other management practices are essential for mastitis control, improved milk quality, and greater profitability of dairy herds.

Management Practices of Bovine Mastitis and Milk Quality on Egyptian Dairies.

Milk production continues to be the main source of income for dairy producers, and mastitis continues to be the major health challenge for dairy cows worldwide. The objective of the current study was to describe the different management practices implemented in Egyptian dairies, which may influence mastitis and improve milk quality. An in-person survey was completed with herd managers and owners of 20 Egyptian dairies selected using a stratified random sample from four of Egypt's milk sheds. The questionnaire included 80 questions that inquired about herd demographics, mastitis status and control, milking practices, and management practices of the study dairies. Statistical analyses included descriptive statistics, multiple factor analysis (MFA), and hierarchical clustering to identify the important principal components and different dairy clusters. Of the surveyed herds, 69.50% had less than 500 lactating cows, with Holstein as the main cow breed. The reported average milk production on the study herds was 31.1 (SE ± 1.10) Kg/cow/day. Housing of lactating, dry, and close-up cows was in open lots. The majority of the dairies milked cows were three times per day (90.63%), the remaining milked cows four (5.00%) or a mix of four and three times per day. Furthermore, herringbone parlor design was the most common parlor design (66.79%) in the study dairies. The most common disinfectants used for both pre- and post-milking teat dip were iodine-based, 90.0% and 95.0%, respectively, while 52.16% of the dairies reported that their milkers wore gloves during milking. The reported mean annual percentage of mastitis was 52.3%, as a percent of the milking herd. The study dairies reported the inspection of udder health through either visual inspection (95.00%), udder hygiene score (86.88%), teat end score (71.88%), and/or using CMT (54.91%). Contagious mastitis pathogens were reported in 45.2% of the study herds. More than 50% of the study herds relied on importing pregnant cows or pregnant heifers as replacements. Multiple factor analysis identified 20 questions and represented 5 components of variability related to mastitis on dairies. The current survey of Egyptian dairies described the herd demographics and different management practices related to mastitis control and prevention. All the study dairies relied on the blanket intramammary antimicrobial drugs at dry off when current research elsewhere has identified selective dry cow therapy as an integral component of antimicrobial stewardship on dairies. Further research is required to identify the association between different management factors and the occurrence of mastitis.

Multiple roles of LncRNA-BMNCR on cell proliferation and apoptosis by targeting miR-145/CBFB axis in BMECs

Bovine mastitis is one of the most serious and costly disease affecting dairy cattle production. The present study explored the inflammatory response and autoprotective mechanism of a novel specific high expression BMNCR (bovine mastitis related long non-coding RNA) in S. aureus induced mastitis by miR-145/CBFB axis in dairy cows from the perspective of molecular genetics. In bovine mammary epithelial cells, we preformed loss of function experiments to detect changes in cytokine, proliferation and apoptosis by qRT-PCR, western blot, flow cytometry and EdU staining. The results demonstrated that BMNCR significantly increased cell apoptosis, and inhibited cell proliferation. However, the secretion of IL-1α, IL-2, IL-6, IL-8 and IL-12 were enhanced after knock-down BMNCR. Bioinformatics analysis demonstrated that BMNCR could target 8 miRNAs, in-depth analyses indicated that BMNCR acts as a molecular sponge for bta-miR-145 and CBFB was one of 23 target gene of bta-miR-145 . The results of the present study demonstrated that the role of BMNCR in S. aureus induced mastitis can be mediated by sponge bta-miR-145 activating CBFB expression. BMNCR could be a potential target for mastitis diagnosis and therapy, which may enrich the theoretical research of therapeutic intervention, and further increase milk yield and improve milk quality.

Maternal sodium acetate supplementation promotes lactation performance of sows and their offspring growth performance.

Milk yield and composition are critical determining factors for the early growth and development of neonates. The objective of this experiment was to comprehensively evaluate the effects of dietary sodium acetate (SA) supplementation on the milk yield and composition of sows and the growth performance of their offspring. A total of 80 sows (Landrace×Yorkshire, 3 to 6 parity) were randomly assigned to 2 groups (with or without 0.1% SA) from d 85 of gestation to d 21 of lactation. The result shows that maternal 0.1% SA supplementation significantly increased sows milk yield, milk fat, immunoglobulin A (IgA) and IgG content in milk (P<0.05), with the up-regulation of short-chain fatty acids receptors (GPR41 and GPR43) expression and the activation of mammalian target of rapamycin complex C1 (mTORC1) signaling pathway. Consistently, in our invitro experiment, SA also activated mTORC1 signaling in porcine mammary epithelial cells (P<0.05). Furthermore, the improvement of milk quality and quantity caused by maternal SA supplementation led to the increase in body weight (BW) and average daily weight gain (ADG) of weaning piglets, with the improvement of gut health and colonization of the beneficial bacteria (P<0.05). In conclusion, maternal supplementation of 0.1% SA improved the lactation performance (milk yield and milk fat) of sows, possibly with the activation of GPR41/GPR43-mTORC1 signaling. Furthermore, enhanced milk quality improved growth performance, gut health and the colonization of beneficial microbial flora of their piglets.

Mastitis prevention and control: Integration of microbiological and management approaches

Mastitis is a common cause of reduced dairy productivity in cows and poor milk quality. This paper considers a set of approaches based on microbiological studies and risk analysis aimed at reducing the number of cows with mastitis and improving milk quality. The study is aimed at examining microbial agents isolated from the milk of sick cows and means of ensuring udder health, and identifying the main dangers that arise due to errors in the implementation of mastitis prevention measures. The study included microbiological tests of milk, wipes and udder dipping using chromogenic media. For a qualitative risk assessment, a survey of consulting managers and veterinarians was conducted. The paper presents the results of microbiological tests of 115 samples of milk, 45 reusable napkins, and 111 samples of udder dips using conventional and chromogenic media. The most common microorganisms in milk samples were Streptococcus spp. 34.4% (S. agalactiae and S. disgalactiae), Staphylococcus aureus 31.1%, and Escherichia coli 28.9%. Staphylococcus aureus and Streptococcus spp. it is associated with infectious mastitis, and Escherichia coli – with sanitary mastitis. To reduce the incidence of mastitis, it is important to apply targeted measures aimed at various categories of pathogens. Udder wipes were contaminated with pathogens associated with the development of mastitis. The use of laundry detergent containing bactericidal components is crucial to minimise contamination of reusable udder wipes. Among the dips under study, 40.6% of the samples had a complete bactericidal effect, and 9.9% had no bactericidal effect. 3 factors of high risk of environmental mastitis and 6 factors of sanitary mastitis were identified. The results of the studies were tested on two dairy farms. Correction of high-risk risk factors led to an increase in the quality of milk in terms of somatic cells and the number of bacteria. The results obtained can be useful for improving the system of prevention and optimisation of mastitis treatment on dairy farms

VETERINARY AND SANITARY EVALUATION OF HOLSTEIN MILK

Livestock in Kazakhstan occupies about 43% of the total gross agricultural output, is the main source of employment, nutrition and income of the rural population and its development is one of the main strategic economic objectives of the Republic. The dairy industry has always been and remains the leading sector of the Republic's agro-industrial complex, accounting for about 20% of the volume of food produced in Kazakhstan. The provision of the population with quality products is closely connected with the development of cattle breeding; in turn, the provision of dairy products largely depends on the efficiency of dairy cattle breeding and the fullest use of its potential. To date, the main task in dairy cattle breeding is to increase cow productivity, as well as to improve milk quality: to increase the amount of fat, protein and dry matter. The development of the dairy industry in the Republic of Kazakhstan has a positive trend. The range of dairy products is wide and is approaching European standards in terms of quality. New brands using high-tech production lines have emerged in Kazakhstan's domestic market, which creates a special demand from consumers for competitive advantages in terms of product quality.

CircRNA-02191 regulating unsaturated fatty acid synthesis by adsorbing miR-145 to enhance CD36 expression in bovine mammary gland

CD36 functions as a receptor for long-chain fatty acids, promoting the absorption and transport of long-chain unsaturated fatty acids. However, the regulatory influence of upstream circRNAs or miRNAs on its expression in cow mammary gland remains unclear. Herein, we performed high-throughput sequencing to screen for differentially expressed miRNAs and mRNAs in bovine mammary tissue during the late-lactation and the dry period to screen and conducted bioinformatics analysis to identify 420 miRNA/mRNA pairs, including miR-145/CD36. Experimental results indicate that miR-145 can directly target CD36 and inhibit its expression. Additionally, the circRNA-02191 sequence is predicted to contain a miR-145 binding site. As shown by dual luciferase reporter system detection, circRNA-02191 bound to miR-145 and its overexpression significantly reduced the expression of miR-145. Furthermore, the overexpression of miR-145 inhibited triglyceride accumulation, while circRNA-02191 enhanced the expression of the miR-145 target gene CD36. The above results indicate that circRNA-02191 can regulate triglyceride and fatty acid components by binding miR-145 and subsequently alleviating the inhibitory effect of miR-145 on the expression of CD36. Taken together, these findings present a novel approach to improve milk quality by analyzing the regulatory effect and mechanism regulating the circ02191/miR-145/CD36 pathway on fatty acid synthesis in the mammary gland of dairy cows.

Associations among Milk Microbiota, Milk Fatty Acids, Milk Glycans, and Inflammation from Lactating Holstein Cows.

Milk oligosaccharides (MOs) can be prebiotic and antiadhesive, while fatty acids (MFAs) can be antimicrobial. Both have been associated with milk microbes or mammary gland inflammation in humans. Relationships between these milk components and milk microbes or inflammation have not been determined for cows and could help elucidate a novel approach for the dairy industry to promote desired milk microbial composition for improvement of milk quality and reduction of milk waste. We aimed to determine relationships among milk microbiota, MFAs, MOs, lactose, and somatic cell counts (SCC) from Holstein cows, using our previously published data. Raw milk samples were collected at three time points, ranging from early to late lactation. Data were analyzed using linear mixed-effects modeling and repeated-measures correlation. Unsaturated MFA and short-chain MFA had mostly negative relationships with potentially pathogenic genera, including Corynebacterium, Pseudomonas, and an unknown Enterobacteriaceae genus but numerous positive relationships with symbionts Bifidobacterium and Bacteroides. Conversely, many MOs were positively correlated with potentially pathogenic genera (e.g., Corynebacterium, Enterococcus, and Pseudomonas), and numerous MOs were negatively correlated with the symbiont Bifidobacterium. The neutral, nonfucosylated MO composed of eight hexoses had a positive relationship with SCC, while lactose had a negative relationship with SCC. One interpretation of these trends might be that in milk, MFAs disrupt primarily pathogenic bacterial cells, causing a relative increase in abundance of beneficial microbial taxa, while MOs respond to and act on pathogenic taxa primarily through antiadhesive methods. Further research is needed to confirm the potential mechanisms driving these correlations. IMPORTANCE Bovine milk can harbor microbes that cause mastitis, milk spoilage, and foodborne illness. Fatty acids found in milk can be antimicrobial and milk oligosaccharides can have antiadhesive, prebiotic, and immune-modulatory effects. Relationships among milk microbes, fatty acids, oligosaccharides, and inflammation have been reported for humans. To our knowledge, associations among the milk microbial composition, fatty acids, oligosaccharides, and lactose have not been reported for healthy lactating cows. Identifying these potential relationships in bovine milk will inform future efforts to characterize direct and indirect interactions of the milk components with the milk microbiota. Since many milk components are associated with herd management practices, determining if these milk components impact milk microbes may provide valuable information for dairy cow management and breeding practices aimed at minimizing harmful and spoilage-causing microbes in raw milk.

Rationale for the prevention of mastitis in cows during the dry period and after calving

Testing cows for mastitis before starting and treating all milch cows with a long-acting antimicrobial agent is an important component of the preventive preparation of animals for the dry period. In addition, determining the sensitivity of pathogens isolated on the farm and rotating antimicrobials increases the effectiveness of therapy and reduces the risk of resistant strains of microorganisms. The purpose of this study was to determine the preventive and therapeutic effects of preparations based on povidone-iodine and cefquinome sulfate for cows with mastitis. The following methods were used in the study: calculation of the total number of somatic cells by flow cytometry; California test; sensitivity to antimicrobial agents by agar disks; clinical and physiological method; statistical method. During the examination of cows for mastitis, it was identified that in the control group the number of somatic cells averaged 450 thousand/cm3, the total number of microorganisms was 130 thousand. In cows of the experimental group, productivity was 23.6%, the number of somatic cells was 600 thousand/cm3, microorganisms – 550 thousand CFU/cm3. It was identified that the isolated microflora showed high sensitivity to the preparation based on povidone-iodine and cefquinome sulfate. Therefore, udder conservation for cows of the experimental group with signs of mastitis was conducted with a product based on povidone-iodine, which affected the increase in lactation and improvement of milk quality after calving. The criteria for milk in the experimental group at the end of the experiment corresponded to the grade extra – 30%, top – 60%, and first – 10%. As a result of the therapy, lactation improved in cows, and the quality of milk corresponded to the first grade. At the end of the study, the quality of milk in cows of the control group corresponded to the extra Grade – 10%, top – 40%, and first – 50%. The practical value of the study lies in the prevention of mastitis on the farm, improving the quality of the resulting products, reducing the cost of veterinary care and culling animals

The role of power relationships, trust and social networks in shaping milk quality in Kenya

The objective of this study was to examine social networks in dairy value chains (DVCs) in Kenya and understand how DVC actors’ power relationships and trust influence their behaviour regarding milk quality. We conducted a stakeholder analysis using the Net-Map tool in Laikipia, Nakuru and Nyandarua counties in Kenya. VisuaLyzer software was used to analyse the social networks. Thematic content analysis of the discussions, recorded during the mapping exercise, was undertaken using ATLAS.ti. Formal DVC had more actors and dense social networks characterised by vertical and horizontal integration, high levels of power asymmetries between actors, limited trust and short-term contractual arrangements. Informal DVC was characterised by fewer actors and less dense social networks, low levels of power asymmetries between actors and a high level of trust due to the existence of reciprocal personal relationships. Milk was perceived to be of higher quality in the formal value chain reflecting top-down enforcement of milk standards, bottom-up collective action, power asymmetries and contractual relationships. Poor milk quality management in the informal DVC underscores the need for powerful actors, e.g. regulatory agencies, and buyers such as processors, to influence other DVC actors’ behavioural change. Understanding and leveraging DVC social networks and actors’ power and addressing power asymmetries and enhancing trust between actors will increase compliance with milk quality standards. There is an urgent imperative to design policies and interventions which empower DVC actors, by providing economic incentives, enhancing their skills and knowledge and their access to infrastructure which facilitates milk quality improvement.

Hygiene products for udder health of lactating cows

The introduction of the “Milking Protocol” on the farm is a mandatory condition for preventing intramammary infections, maintaining cows' productivity, and improving milk quality. Treating udders with hygiene products is an effective preventive udder care measure in most dairy herds. The choice of an antiseptic agent for udder health should be based on its proven effectiveness, which is necessary to register the drug as a veterinary medicinal product. The purpose of the study was to get acquainted with the current literature on the use of hygiene products for the health of the udder of lactating cows. While writing this review article, we got acquainted with the results of modern scientific research, conducted their analysis and theoretical justification, and summarized the data obtained on using hygienic means for sanitizing the udder of lactating cows. For this purpose, the Polissia National University scientific library funds, scientific search systems Science-Direct, and PubMed were used. This means that sanitation of the mammary gland should have an antiseptic effect and keep the breasts in good condition. Declared composition of registered drugs in Ukraine: iodine, chlorhexidine, organic acids. Hygienic products include cosmetic surfactants that soften the skin and form a moisturizing hydrophilic layer on the skin. Means for udder hygiene, as a rule, are products of chemical origin, and using these drugs creates a risk of chemical elements entering the milk. An alternative to these potential dangers can be probiotic-based products that are environmentally friendly and harmless to the animal body. In the conditions of war and economic troubles, the specialists of the dairy industry are offered preparations of plant origin for the disinfection of cow udders, where medicinal plants are used as raw materials, from which infusions, decoctions, water extracts, alcohol- and oil-based solutions are prepared. Applying dipping procedures is an integral part of the preventive measures of the anti-mastitis program. The choice of means for disinfecting udders after milking must be made depending on the circulation of pathogens in the herd and consider all factors in the conditions of a specific product. In this regard, I believe that a promising direction of scientific research is the use of nanotechnology in the development of new antiseptics, the study of their effect on the health of the udder of lactating cows, the use of probiotics as a dip, as an alternative to substances of chemical origin.

Genome-wide analysis for the melatonin trait associated genes and SNPs in dairy goat (Capra hircus) as the molecular breeding markers.

Previous studies have reported that the endogenous melatonin level is positively associated with the quality and yield of milk of cows. In the current study, a total of 34,921 SNPs involving 1,177 genes were identified in dairy goats by using the whole genome resequencing bulked segregant analysis (BSA) analysis. These SNPs have been used to match the melatonin levels of the dairy goats. Among them, 3 SNPs has been identified to significantly correlate with melatonin levels. These 3 SNPs include CC genotype 147316, GG genotype 147379 and CC genotype 1389193 which all locate in the exon regions of ASMT and MT2 genes. Dairy goats with these SNPs have approximately 5-fold-higher melatonin levels in milk and serum than the average melatonin level detected in the current goat population. If the melatonin level impacts the milk production in goats as in cows, the results strongly suggest that these 3 SNPs can serve as the molecular markers to select the goats having the improved milk quality and yield. This is a goal of our future study.

Effect of a 60-day organic selenium-supplemented diet on the decrease of somatic cell counts in goat milk.

Selenium is an important element in nutrition, showing great potential in the udder health of dairy goats and in the control of subclinical mastitis. However, there are few studies that evaluated the influence of selenium supplementation on subclinical mastitis in goats. The aim of this study was to evaluate the incidence of subclinical mastitis in dairy goats supplemented with organic selenium (Se yeast) in a semi-arid region. Sixteen Saanen × Toggenburg crossbred lactating goats were allocated randomly into two treatments: with and without addition of organic selenium (Se) to the concentrate. Milk samples were collected every 20days from each udder half to determine the somatic cell count (SSC), chloride content, pH, electrical conductivity, microbiological isolation, composition, and selenium contents. The highest serum selenium concentrations in the blood of these goats occurred at 42days of supplementation (P < 0.001). Goats which received organic selenium supplementation had higher serum selenium concentrations (P < 0.05). The milk composition variables did not differ (P > 0.05) between the tested treatments, teats, and collections. After 60days of supplementation, a difference was observed (P < 0.05) between treatments for SSC, chloride content, and pH. Addition of organic selenium to the diet of dairy goats after 60days of supplementation was promising in reducing the somatic cell count, consequently improving milk quality.

Synergies of feed, management trainings, and genetics on milk production of dairy cows in the tropics: The case of Ethiopian smallholder farmers

Efforts made so far to increase milk production of indigenous cattle by upgrading with exotic genotypes through crossbreeding under smallholder farmer conditions in Ethiopia have resulted in limited improvement. This study was conducted to determine if combining improved feed and management-related trainings with Holstein genetics will synergistically increase the milk production of dairy cows, and to examine the degree to which the increase or improvement is related to the level of exotic genetics involved. A total of 96 smallholder dairy farmers were purposively selected and allocated to one of three treatments reflecting differing degrees of capacity building support: (1) no training and no material support (Control); (2) training provided by another project (PAID) but without material support; (3) enhanced training plus material support (Feed-Mgt). Sixteen extension development agents and eight livestock experts were selected to provide training and weekly on-farm data collection, monitoring, technical support, and messaging reinforcement visits. Enhanced training addressed a broad range of topics related to feed and feeding, improved forage production, milk production and handling, construction and use of improved dairy housing, disease control, and dairy farm record keeping. Material support was in the form of formulated dairy concentrate feed and improved forage planting materials (seeds/seedlings). Data collection included variables describing animal performance, management practice adoption, and milk and butter quality. Tail hair samples for genetic profiling of breed makeup were also collected from all cows in the study. Results showed that there was a very significant effect of treatment (P &amp;lt; 0.001) on milk production, as well as treatment by week interaction (P = 0.034), with the effect of treatment markedly increasing over time (P = 0.032). That is, cows in Feed-Mgt group had up to 26.6% greater milk production compared to those in the Control group. Region and region by treatment interaction have no effects. Cows used in the experiment had varying proportions of Holstein-Friesian genome that ranged between 0 and 100%, suggesting prevalence of indiscriminate crossbreeding. Cows with a high proportion of Holstein genetics in treatment 3 produced more milk as compared to those in control group. Besides, supplemental feed improved body condition, reduced number of services per conception and resulted in higher lactation length of cows on treatment 3 compared with those on treatments 1 and 2 (P &amp;lt; 0.001). Overall, our findings suggest that an integrated approach of improved feed, feeding practices, and management training for smallholder dairy that goes beyond the improvement of genetics will increase milk production, improve milk quality and body condition, and resulted in higher length of lactation.

Efficacy of feeding hydroxy-selenomethionine on plasma and milk selenium in mid-lactation dairy cows

In this study, we aimed to determine the amount of Se transferred to milk and blood of mid- to late-lactation dairy cows when supplemental Se from hydroxy-selenomethionine (OH-SeMet) was fed compared with an unsupplemented group and a group supplemented with a seleno-yeast (SY). Twenty-four lactating Holstein cows (178 ± 43 d in milk) were used in a complete randomized block design for 91 d (7-d covariate period and 84-d treatment period). Treatments were (1) basal diet with an analyzed Se background of 0.2 mg of Se per kg as-fed (control); (2) basal diet + 0.3 mg of Se/kg as-fed from SY (SY-0.3); (3) basal diet + 0.1 mg of Se/kg as-fed from OH-SeMet (OH-SeMet-0.1); and (4) basal diet + 0.3 mg of Se/kg as-fed from OH-SeMet (OH-SeMet-0.3). During the trial, plasma and milk were analyzed for total Se, and plasma was analyzed for glutathione peroxidase activity. The mean plasma and milk Se concentrations exhibited the same relationship, where OH-SeMet-0.3 resulted in the highest values (142 µg/L of plasma and 104 µg/kg of milk), followed by SY-0.3 (134 µg/L and 85 µg/kg), OH-SeMet-0.1 (122 µg/L and 67 µg/kg), and the control group had the lowest values (120 µg/L and 50 µg/kg). The increment of Se in milk induced by OH-SeMet-0.3 (+54 µg/kg) was 54% higher than that induced by SY-0.3 (+35 µg/kg). Additionally, dietary supplementation of 0.2 mg/kg Se from OH-SeMet in the total mixed ration was estimated to be similar to 0.3 mg/kg Se from SY in the total mixed ration when considering the level of Se in the milk. There was no difference in plasma glutathione peroxidase activity between groups; however, OH-SeMet-0.3 significantly decreased somatic cell count. The results confirmed that supplementation with organic Se increases milk and plasma Se concentrations. Moreover, when administered at the same level of supplementation, OH-SeMet was shown to be more efficient than SY in improving milk quality by increasing Se content and decreasing milk somatic cell count.

Predicting milk protein fractions using infrared spectroscopy and a gradient boosting machine for breeding purposes in Holstein cattle

In recent years, increasing attention has been focused on the genetic evaluation of protein fractions in cow milk with the aim of improving milk quality and technological characteristics. In this context, advances in high-throughput phenotyping by Fourier transform infrared (FTIR) spectroscopy offer the opportunity for large-scale, efficient measurement of novel traits that can be exploited in breeding programs as indicator traits. We took milk samples from 2,558 Holstein cows belonging to 38 herds in northern Italy, operating under different production systems. Fourier transform infrared spectra were collected on the same day as milk sampling and stored for subsequent analysis. Two sets of data (i.e., phenotypes and FTIR spectra) collected in 2 different years (2013 and 2019-2020) were compiled. The following traits were assessed using HPLC: true protein, major casein fractions [αS1-casein (CN), αS2-CN, β-CN, κ-CN, and glycosylated-κ-CN], and major whey proteins (β-lactoglobulin and α-lactalbumin), all of which were measured both in grams per liter (g/L) and proportion of total nitrogen (% N). The FTIR predictions were calculated using the gradient boosting machine technique and tested by 3 different cross-validation (CRV) methods. We used the following CRV scenarios: (1) random 10-fold, which randomly split the whole into 10-folds of equal size (9-folds for training and 1-fold for validation); (2) herd/date-out CRV, which assigned 80% of herd/date as the training set with independence of 20% of herd/date assigned as the validation set; (3) forward/backward CRV, which split the data set in training and validation set according with the year of milk sampling (FTIR and gold standard data assessed in 2013 or 2019-2020) using the "old" and "new" databases for training and validation, and vice-versa with independence among them; (4) the CRV for genetic parameters (CRV-gen), where animals without pedigree as assigned as a fixed training population and animals with pedigree information was split in 5-folds, in which 1-fold was assigned to the fixed training population, and 4-folds were assigned to the validation set (independent from the training set). The results (i.e., measures and predictions) of CRV-gen were used to infer the genetic parameters for gold standard laboratory measurements (i.e., proteins assessed with HPLC) and FTIR-based predictions considering the CRV-gen scenario from a bi-trait animal model using single-step genomic BLUP. We found that the prediction accuracies of the gradient boosting machine equations differed according to the way in which the proteins were expressed, achieving higher accuracy when expressed in g/L than when expressed as % N in all CRV scenarios. Concerning the reproducibility of the equations over the different years, the results showed no relevant differences in predictive ability between using "old" data as the training set and "new" data as the validation set and vice-versa. Comparing the additive genetic variance estimates for milk protein fractions between the FTIR predicted and HPLC measures, we found reductions of -19.7% for milk protein fractions expressed in g/L, and -21.19% expressed as % N. Although we found reductions in the heritability estimates, they were small, with values ranging from -1.9 to -7.25% for g/L, and -1.6 to -7.9% for % N. The posterior distributions of the additive genetic correlations (ra) between the FTIR predictions and the laboratory measurements were generally high (>0.8), even when the milk protein fractions were expressed as % N. Our results show the potential of using FTIR predictions in breeding programs as indicator traits for the selection of animals to enhance milk protein fraction contents. We expect acceptable responses to selection due to the high genetic correlations between HPLC measurements and FTIR predictions.

Relationships between body- and udder-related type traits with somatic cell counts and potential use for an early selection method for water buffaloes (Bubalus bubalis).

Water buffalo milk is a reliable source of high-quality nutrients; however, the susceptibility of mastitis in buffaloes must be taken into consideration. An animal with somatic cell count (SCC) of greater than 250,000 cells/mL is reported to be likely to have mastitis which has serious adverse effects on animal health, reproduction, milk yield, and milk quality. Type traits (TTs) of water buffalo can affect SCC in animal milk to some extent, but few reports on the correlation between SCC and TTs are available. In this study, a total of 1908 records collected from 678 water buffaloes were investigated. The general linear model was used to identify factors associated with phenotypic variation of the somatic cell score (SCS) trait, including parity, lactation length, calving year, and calving season as fixed effects. Using PROC CORR analysis method, taking calving year and lactation length as covariates, the correlation co-efficient between TT and SCS was obtained. Our results showed that correlation co-efficients between the 45 TTs with SCS ranged from 0.003 to 0.443 (degree of correlation). The correlation between udder traits and SCS was greater than that between body structure traits and SCS. Among udder traits, distance between teats (including front and rear teat distance [r = 0.308], front teat distance [r = 0.211], and teat crossing distance [r = 0.412]) and teat circumference (r = 0.443) had the highest correlation with SCS, followed by the leg traits including rear leg height (r = -0.354) and hock bend angle (r = -0.170). Animal with high rear legs (>48 cm) and short teat crossing distance (<17 cm), and narrow teat circumference (<11 cm) exhibited low SCS. Using four nonlinear models (Von Bertalanffy, Brody, Logistic, and Gompertz), the optimal growth curves of the TTs highly correlated with the SCS (rear leg height and teat crossing distance) were fitted, and the correction co-efficients of these two TTs rear leg height and teat crossing distance of animal from young age (2 mo old) to first lactation (35 mo old) were attained for establishment of early selection method for water buffaloes with low SCS. This study provides theoretical support for early selection of low-SCS water buffaloes and lays a foundation for improving milk quality and promoting healthy development of water buffalo's dairy industry.

Adaptation of breeding goats for the milk purposes to climate conditions

This article presents valuable opinions on the importation of purebred young goats from foreign countries and its impact on various aspects of dairy goat breeding. The importation of purebred young goats plays a significant role in the establishment of farm subjects specializing in dairy goat breeding. One aspect highlighted in the article is the importance of introducing purebred young goats to improve the genetic pool of local dairy goat populations. By bringing in high-quality genetics from foreign countries, dairy goat breeders can enhance the productivity, milk yield, and overall performance of their herds. This can lead to increased milk production and improved milk quality, benefiting the dairy industry as a whole. Furthermore, the article discusses the significance of adapting imported dairy goats to the local natural climatic conditions. Importing goats from foreign countries may expose them to different climates, which can impact their health and productivity. Proper adaptation measures are essential to ensure the well-being of these animals and their successful integration into the local environment. Moreover, the article explores clinical signs and morphological characteristics of blood in mother goats during the process of adaptation to the natural climatic conditions. Monitoring and understanding these physiological changes are crucial for ensuring the well-being and health of the mother goats, as well as the successful rearing of their offspring.

Efficiency of probiotic culture consortium application for disinfection of dairy farm premises and prevention of mastitis in cows.

In this work, the effect of probiotics on the state of the microbial background of the livestock building, on the state of udder teats, and on the prevalence of latent mastitis was investigated. Long-term use of the consortium has bactericidal activity against all cultures studied, especially the causative agent of mastitis, Staphylococcus aureus, except Proteus mirabilis, Proteus vulgaris, and Escherichia coli. The washes from animal housings and milk samples were collected from the dairy farms "Astana-Onim" Joint Stock Company and "Rodina" Limited Liability Partnership (Kazakhstan). The cleaning solutions and probiotic agents were applied directly to the udder teats of cows before and after milking. Diagnosis of subclinical mastitis was performed using the Kenotest rapid mastitis test. Directly counting the number of somatic cells in the collected milk samples from each cow was performed on a somatic cell counter. Pathogenic microorganisms, including S. aureus bacteria (50% of samples) and bacteria of the E. coli group, Enterobacter aerogenes, and P. mirabilis (36% of samples), were detected on the udder skin and milk wipes. Using a consortium of probiotic microorganisms positively affects the mammary gland more quickly than using mastitis prevention agents alone. Probiotic use for a month resulted in a significant improvement in udder teat condition, with 60.7% of teats showing normal physiological reaction to milking, a decrease in complicated hyperkeratosis, and an increase in uncomplicated mastitis. The studies showed that in the experimental group, there was a 1.5-fold reduction in the number of cows with clinically pronounced mastitis. The experimental group showed no significant changes in the number of animals with high somatic cell levels before and after the study, while the control group without probiotics had a significant increase in diseased animals after 1 month. The use of a probiotic consortium has shown promising results in reducing the incidence of mastitis and improving milk quality in cows.