Milk Production Characteristics Research Articles

Effect of Rumen-Protected L-Tryptophan or L-Ascorbic Acid on Plasma Metabolites and Milk Production Characteristics of Lactating Holstein Cows during Summer Conditions.

This study investigated the effects of rumen-protected L-tryptophan or L-ascorbic acid supplementation on the productivity of lactating Holstein cows during a high-temperature period. Thirty cows were assigned to three dietary groups: control (CON), treatment 1 (TRT 1; rumen-protected L-tryptophan, 20 g/cow/d), and treatment 2 (TRT 2; rumen-protected L-ascorbic acid, 20 g/cow/d). As the high-temperature period progressed, the decrease in milk yield and dry matter intake (DMI) in the TRT 1 and TRT 2 groups was lower than that in the CON group. The total protein level in the plasma of the TRT 1 group was higher than that in the CON group (p < 0.05). Milk melatonin concentration was higher in the TRT 1 group than in the CON and TRT 2 groups (p < 0.05). Thus, the present results indicate that rumen-protected L-tryptophan or L-ascorbic acid has positive effects in preventing declines in DMI and milk yield by reducing heat stress in Holstein cows. In particular, rumen-protected L-tryptophan is considered effective in increasing the melatonin concentration in milk.

A Systematic Review on Buffalo Breeds, Lactation Performance, and Buffalo Milk Production Characteristics in Sri Lanka

Purpose: The current study aimed to systematically review the publications originating from Sri Lanka on buffalo milk to identify potential dairy buffalo breeds and their lactation performances, milk composition, physicochemical properties, and products originating from buffalo milk.Research Method: Articles published over the last 6 decades were found through Scopus and Google Scholar databases using keywords. Original Research articles which are relevant and published in English were only selected. The six-step selection process in line with the Preferred Reporting Items for Systematic Reviews and Meta-analysis Approach (PRISMA) was adopted.Findings: The majority of the publications focused on product development aspects rather than buffalo milk production aspects. Pure breeds of the locals, Murrah, Surti, and Nili-Ravi, and their crossbreeds are frequently cited in the literature. The daily average milk yields of Murrah, Local, Surti, and Nili-Ravi pure breeds were 4.7±2.3, 3.1±1.3, 3.0±1.19, and 1.2 L, respectively. Daily milk yields of the crossbreeds ranged from 1.1 – 5.0 L. Average lactation lengths were largely dependent on the breed in which Murrah recorded the highest (341±100 days). The average lactation length of the local breed was exceptionally shorter (156±27 days) than that of the exotic breeds (&gt;235 days). The calving interval of the Murrah and Local buffaloes was the same (636 d). Pure breeds of Surti and Nili-Ravi recorded calving intervals of 489 and 411 d, respectively. Whereas, it ranged from 417-477 d among crossbreeds. Studies focused on milk compositions and physicochemical properties were extremely rare. Curd and cheese were the most focused products originating from buffalo milk.Value: This study summarises the buffalo milk production aspects in Sri Lanka and identifies research gaps in the area. Current literature reflects a satisfactory level of information relevant to the buffaloes reared in the Dry-Zone. This study recommends more research in milk composition analysis and lactation performance of the breeds and buffalo production in the Low-Country Wet Zone and Up-Country regions.

Relationship of genetic Polymorphisms of FADS2 gene in some productive traits of Holstein cows in Iraq

The research was conducted at the Greater Khalis Cows Station in Diyala Governorate and the central laboratory of the College of Agriculture - Tikrit University for the period from 12/13/2020 to 2/1/2022, on a sample of 63 Holstein cows (dairy), with the aim of extracting the genetic material and identifying the genotypes polymorphism of the gene (FADS2) and the relationship of these genotypes to the characteristics of milk production and its components, as well as the study of the distribution ratios of its structures in the herd, the frequency of the obtained alleles, and the calculation of the chi-square value (χ2). Where the distribution percentage of the genotypes of the FADS2 gene in the cow sample studied was 25.40, 60.32 and 14.28 for the genotypes AA, AG and GG, respectively, the frequency of the A allele was 0.56, while the frequency of the G allele was 0.44 according to the analysis of the FADS2 gene in the study current. The effect of the FADS2 genotypes on the proportions of milk components was significant (P&lt;0.05), as cows with the hybrid genotype AG achieved the highest averages in the ratios of (non-fat solids, protein, lactose), which amounted to (7.79 ± 0.15), (2.85 ± 0.06) and (4.19 ± 0.09) respectively, while cows with a GG genotype gave the lowest averages for the mentioned traits respectively, which amounted to (7.34 ± 0.22), (2.67 ± 0.08) and (3.94 ± 0.13)%, for the FADS2 gene for the studied samples. It can be concluded from the study of genetic variation of the FADS2 gene that it is possible to develop plans for genetic improvement in milk-producing cows.

Long-term effects of 3-nitrooxypropanol on methane emission and milk production characteristics in Holstein-Friesian dairy cows

The objective was to determine the long-term effect of 3-nitrooxypropanol (3-NOP) on CH4 emission and milk production characteristics from dairy cows receiving 3-NOP in their diet for a full year, covering all lactation stages of the dairy cows. Sixty-four late-lactation Holstein-Friesian cows (34% primiparous) were blocked in pairs, based on expected calving date, parity, and daily milk yield. The experiment started with an adaptation period of 1 wk followed by a covariate period of 3 wk in which all cows received the same basal diet and baseline measurements were performed. Directly after, cows within a block were randomly allocated to 1 of 2 dietary treatments: a diet containing on average 69.8 mg 3-NOP/kg DM (total ration level, corrected for intake of nonsupplemented GreenFeed bait) and a diet containing a placebo. Forage composition as well as forage-to-concentrate ratio altered with lactation stage (i.e., dry period and early, mid, and late lactation). Diets were provided as a total mixed ration, and additional bait was fed in GreenFeed units (C-Lock Inc.), which were used for emission measurements. Supplementation of 3-NOP did not affect total DMI, BW, or BCS, but resulted in a 6.5% increase in the yields of energy-corrected milk and fat- and protein-corrected milk (FPCM). Furthermore, milk fat and protein as well as feed efficiency were increased upon 3-NOP supplementation. Overall, a reduction of 21%, 20%, and 27% was achieved for CH4 production (g/d), yield (g/kg DMI), and intensity (g/kg FPCM), respectively, upon 3-NOP supplementation. The CH4 mitigation potential of 3-NOP was affected by the lactation stage dependent diet to which 3-NOP was supplemented. On average, a 16%, 20%, 16%, and 26% reduction in CH4 yield (g/kg DMI) was achieved upon 3-NOP supplementation for the dry period, and early, mid, and late-lactation diets, respectively. The CH4 mitigation potential of 3-NOP was affected by the length of 3-NOP supplementation within a lactation stage dependent diet and by variation in diet composition within a lactation stage dependent diet as a result of changes in grass and corn silage silos. In conclusion, 3-NOP reduced CH4 emission from cows receiving 3-NOP for a year, with a positive effect on production characteristics. The CH4 mitigation potential of 3-NOP was influenced by diet type, diet composition, and nutrition value, and the efficacy of 3-NOP appeared to decline over time but not continuously. Associated with changes in diet composition, increased efficacy of 3-NOP was observed at the start of the trial, at the start of a new lactation, and, importantly, at the end of the trial. These results suggest that diet composition has a large effect on the efficacy of 3-NOP, perhaps even larger than the week of supplementation after first introduction of 3-NOP. More studies are needed to clarify the long-term effects of 3-NOP on CH4 emission and to further investigate what influence variation in diet composition may have on the mitigation potential of 3-NOP.

Impact of Using Oilseed Industry Byproducts Rich in Linoleic and Alpha-Linolenic Acid in Ruminant Nutrition on Milk Production and Milk Fatty Acid Profile.

Milk contains more than 400 different fatty acids, some of which play a positive role in promoting human health. The profile of fatty acids in milk can be enhanced by providing animals with plant-based resources that possess feeding characteristics adequate for favorable changes in the fatty acid composition and increasing healthy fatty acids in milk. This review summarizes the available 41 research studies on the utilization of oilseed industry byproducts rich in linoleic acid (hemp, pumpkin, sunflower) and alpha-linolenic acid (camelina and linseed) in dairy cow, sheep, and goat nutrition; their impact on milk production characteristics; and potential to improve fatty acid composition of milk through the diet. This review illustrates that incorporating byproducts into the diet for dairy ruminants generally does not have any adverse effects on both milk production and composition. A similar trend of improvement in milk fatty acid profile was observed when ruminants were fed diets supplemented with camelina, linseed, and sunflower byproducts, while no significant changes were noted with pumpkin byproducts. Hempseed byproducts showed potential for use as an alternative ingredient in dairy ruminant diets. Nevertheless, more in-depth research investigating the inclusion of selected byproducts is required before valid conclusions can be drawn regarding their value.

Milk proteomic analysis reveals differentially expressed proteins in high-yielding and low-yielding Guanzhong dairy goats at peak lactation.

The aim of this experiment was to investigate the differential proteomic characteristics of milk from high- and low-yielding Guanzhong dairy goats during the peak lactation period under the same feeding conditions. Nine Guanzhong dairy goats with high yield (H: 3.5 ± 0.17 kg/d) and nine with low yield (L:1.2 ± 0.25 kg/d) were selected for milk proteomic analysis using tandem mass tag technology. A total of 78 differentially expressed proteins were identified. Compared with L, 50 proteins including HK3, HSPB1 and ANXA2 were significantly upregulated in H milk, while 28 proteins including LALBA and XDH were significantly downregulated. Bioinformatics analysis of the differentially expressed proteins showed that galactose metabolism, purine metabolism, glycolysis/gluconeogenesis, MAPK signaling pathway, regulation of actin cytoskeleton and other pathways were closely related to milk yield. HK3, HSPB1, ANXA2, LALBA and XDH were important candidate proteins associated with the milk production characteristics of Guanzhong dairy goats. Our data provide relevant biomarkers and a theoretical basis for improving milk production in Guanzhong dairy goats.

Effects of evaporative cooling systems on the performance of lactating sows in a tropical climate.

This study evaluated litter performance, behavioral and physiological parameters, and milk characteristics of sows submitted to different thermal environments. Fifty sows were distributed in a completely randomized design with two treatments: an evaporative cooling system (ECS) and a conventional system (CS). Sow and its litter were characterized as an experimental unit. The animals were weighed at equalization and weaning. Feed intake, milk production, and bromatological characteristics of milk were measured; the sows respiratory rate, rectal, and surface temperature were monitored. Litter uniformity was determined at equalization and weaning. Behaviors of the sows and litters were monitored for 24 h on the 7th and 15th day of lactation. Temperature and relative humidity inside the maternity was 25.00 to 28.00 °C and 26.00 to 32.55 °C and 30.00 to 70.00% and 70.00 to 88.00%, respectively, considering ECS and CS. Nutritional quality of the milk remained stable during lactation in both systems evaluated. ECS improved the average weight of the piglets, weaning weight, and daily milk production by 0.038, 0.699, and 2.31 kg/day, respectively. Sows housed in the ECS had a reduction in physiological parameters and, increase in inactive alert behavior (1.79 percentage points) and breastfeeding behavior. Piglets showed a decrease of 2.43% in the range of feedings at night and 0.15% during the day. ECS provided better comfort to the sows at the expense of the CS and, consequently, better litter performance.

Productivity and milk quality indicators of cows of the created “Bashkir type” black-and-white breed with the introduction of the balanced energy complex “Felucen K1-2” into the diet

The volume and quality of milk are the determining indicators of the efficiency of dairy farming. The diet of dairy cows has a significant impact on the biological parameters of milk productivity and production characteristics of milk. The work was carried out to determine the optimal dosage of the energy complex “Felucen K1-2” in the diet of cows of the created “Bashkir type” black-and-white breed in the conditions of the agricultural production complex “Hero” of the Chekmagushevsky district of the Republic of Bashkortostan. To achieve this goal, milk productivity was determined for 100 days of lactation, for 305 days, and also determined the dynamics of average daily milk yield by month of lactation. For the experiment, 48 cows were selected, divided into 4 groups of 12 animals each. The energy complex “Felucen K1-2” was added to the diet of cows in the experimental groups in the amount of 250 g, 300 and 350 g of the additive per animal per day. The results of the studies indicate an increase in the mass fraction of fat and protein in milk from cows that consumed the energy complex. This is observed both in dynamics over the months of the experiment and in the total amount for the entire period of research. The use of the additive in the diet of animals showed its effectiveness and contributed to an increase in milk yield per cow and improvement in the quality of milk, while the maximum effectiveness was observed at an average dosage (300 g per day per cow).

Genome‐Wide Association Study for High Milk Yield in Saudi Arabian Dromedary using Whole Genome Sequencing

The camels have attracted scientific attention due to their unique agricultural characteristics and are used for a variety of purposes, including milk and meat production. To exploit their full potential, it is essential to improve our understanding of the genetic makeup of these animals. Advances in molecular breeding have expanded our knowledge of the genetic architecture of complex traits through genome‐wide association studies (GWAS). This study aimed to identify genome‐wide variants, annotate their functions, and examine the genetic variants linked to milk production in camels. We used whole‐genome sequencing data of 61 dromedary camels to perform a genome‐wide association study for investigated milk traits using a logistic regression model. After variant calling in all 61 genome samples and subsequent rigorous filtering processes, we identified 306,310 single nucleotide polymorphisms (SNPs) across all genomes. Among the 306,310 identified SNPs, a subset of 28 SNPs demonstrated statistical significance (p &lt; 5 × 10−4) in association with milk traits in dromedaries. These significant SNPs were found within 13 locations of candidate genes, namely TYRP1, DLC1, GPC5, SLC24A4, NEMP2, and SLC14A1, suggesting their potential relevance to milk production characteristics in this species. The results of our GWAS unravel the complex genetic landscape of milk production in dromedary camels and provide a list of significant SNPs and candidate genes, providing valuable information for further investigations to understand the molecular mechanisms behind this important economic trait.

A Research on Fertility, Herd Life, Milk Production and Milk Quality Characteristics of Simmental (Fleckvieh) Cows: 2. Milk Quality

The aim of this study was to determine the milk quality characteristics of Simmental (SIM) cows of Austrian origin, which have increased the interest of breeders in Türkiye in recent years. For this aim, the milk analysis results of a farm located in Menemen County, İzmir/Türkiye from 2012 to 2021 were used. Milk fat (MF, %), protein (MP, %), lactose (ML, %), total dry matter (TDM, %) contents and somatic cell count (SCC, cell/ml) were determined. In order to determine the current situation, milk samples were taken from the cows (90 heads) in August 2021, and in addition to the above milk components, the solid non-fat (SNF) and freezing point (FP) were determined. The effects of sampling season, calving month, lactation month, sampling season x calving month and sampling season x lactation month interactions were found to be statistically significant for all traits (P&lt;0.05). Parity and calving month effects on Log10SCC were also detected to be statistically significant (P&lt;0.05). The mean MF, MP, ML, TDM, FP and SCC of SIM cattle were 3.71±0.018%, 3.42±0.009%, 4.63±0.009%, 12.49±0.03, -0.535±0.003oC and 5.14±0.01 (138.038 cells/ml), respectively. It was concluded that the milk components of Austrian-origin SIM cattle are not very different from the Holstein-Friesian (HF) breed, however, in the low SCC average for many years, besides the important contribution of the measures taken against mastitis in the farm, the resistance against mastitis may be higher in this genotype. This situation is thought to be the reason why breeders in Türkiye prefer Austrian-origin SIM cattle in addition to high milk yield and carcass weight.

Relationship of the Mutation (C2006A) in the GDF9 Gene in the Productive Performance of Local and Shami Goats

This study was conducted at the Ruminant’s Research Station, Office of Agricultural Research, Ministry of Agriculture, Iraq, For the period from 20/12/2021 to 1/9/2022, to detect GDF-9 gene polymorphism in Local and Shami goat, The genetic material was separated and nucleotide sequencing technology was used to detect mutations in the studied segment of (GDF9) gene, to determine the relationship of the resulting genotypes to the characteristics of growth, milk production and Litter size. The results of the study showed the presence of the mutation (C2006A) in the GDF-9 gene in both local and Shami goats. And it appeared with two genotypes were identified, wild (CC) and hybrid (CA), as the percentage of individuals carrying the wild genotype was (90.91, 92.31)% compared to the hybrid individuals (9.09, 7.69)% in the local and Shami samples, respectively, and the allelic frequency of the wild allele C was superior in Both strains (95, 96% balanced by the mutant allele A (4,5%). The results showed a significant effect of the polymorphism of the mutation (C2006A) in the characteristics of the weaning weight and the current weight in the local sample and in favor of the individuals carrying the hybrid genotype CA (19.25, 38.19) kg, while in the Shami goat sample, a significant effect was found for the genetic variation caused by the mutation (C2006A) in weight at birth for the benefit of individuals carrying the hybrid genotype (2.93) kg, and the results showed a significant effect of the multiplicity of genetic manifestations of the mutation (C2006A) in producing Total milk and Litter size in local and Shami goats in favor of individuals carrying the hybrid genotype CA (454.23, 497.39) kg and (1.57, 1.89) Kids/litter, compared to individuals carrying the wild genotype CC (450.10, 441.27) kg (1.21, 1.11) Kids/litter in the local and Shami samples, respectively.

Association Between Genetic Polymorphism of Mutation (G5736A) in the BMP-15 Gene with Productive Performance of Local and Shami Goats

The study was conducted at the ruminant research station of the Agricultural Research Department / Ministry of Agriculture on a sample consisting of 44 local goats and 52 Shami goats, while the laboratory part was conducted in Scientific Progress Laboratory, for the period from 12/20/2021 to 9/1/2022. The nucleotide sequencing technique was used to detect mutations in The second exon region of the (BMP15) gene to determine the relationship of the resulting genotypes to economic traits (growth, milk production and litter size). The results showed that there are two genotypes, the wild (GG) and the hybrid (GA), as the percentage of individuals carrying the wild genotype was (90.91, 67.31) % compared to the hybrid individuals (9.09, 32.6) % respectively, in the local and Shami goat samples, and the allelic frequency of the wild allele G in both groupss was (0.95, 0.66)% compared to the mutant allele A (0.05, 0.34)%. for both groupss goats, the wild type individuals were superior in birth weight and did not show any significant effect of this mutation on the rest of the growth traits (19.03, 21.0) kg, as for the characteristics of milk production, the individuals carrying the wild genotype also excelled in the characteristic of total milk production in both groupss. (467.4, 490.4) kg compared to individuals carrying the hybrid genotype GG (422.1, 457.1) kg respectively, While no significant effect of the mentioned mutation appeared in litter size for both groups.

Comparative Analysis of Rumen Microbiota Composition in Dairy Cows with Simple Indigestion and Healthy Cows.

Simple indigestion in cows leads to substantial economic losses in the dairy industry. Despite ongoing efforts, an effective treatment for this issue remains elusive. Previous studies have emphasized the vital role of rumen microbes in maintaining ruminant health. To deepen our comprehension of the intricate interplay between rumen microbiota and simple indigestion, we undertook a study involving the analysis of rumen fluid from eight cows with simple indigestion and ten healthy cows. Additionally, we collected data pertaining to milk production, rumination behavior, and rumen characteristics. The results showed that cows with simple indigestion displayed significantly lower milk yield, reduced rumination duration, and weakened rumen contraction when contrasted with the healthy cows (p < 0.05). However, no significant difference in microbiota α-diversity emerged (p > 0.05). Principal coordinate analysis (PCoA) illuminated substantial variations in rumen microbial structure among the two groups (p < 0.05). Further analysis spotlighted distinctive bacteria in the rumen of the cows with indigestion, including Allisonella, Synergistes, Megasphaera, Clostridium_XIVb, Campylobacter, and Acidaminococcus. In contrast, Coraliomargarita, Syntrophococcus, and Coprococcus are the dominant bacterial genera in the rumen of healthy dairy cows. Importantly, these key bacterial genera also dominated the overarching microbial interaction network. The observation suggests that changes in the abundance of these dominant bacterial genera potentially underlie the principal etiology of cows with simple indigestion. The present findings can provide insights into simple indigestion prevention and treatment in dairy cows.

Potential of Endangered Local Donkey Breeds in Meat and Milk Production

The problem of the erosion of animal genetic resources is evident in certain local donkey breeds, and their long-term sustainability can be achieved by economically repositioning them. To develop alternative and sustainable commercial programs, the meat and milk production characteristics of Istrian donkey and Littoral Dinaric donkey breeds were investigated. The meat production characteristics were examined in mature males, whose carcasses were dissected, and meat composition was determined using NIT spectrophotometry and gas chromatography. Milk yield and milk composition were determined in jennies in second or subsequent lactations by measuring milk volume and using infrared spectrometry and gas chromatography. Compared to the Littoral Dinaric donkey, the Istrian donkey has a higher carcass weight and dressing percentage (p &lt; 0.001). The share of boneless meat in relation to live weight was 28.27% in the Istrian donkey and 26.18% in the Littoral Dinaric donkey. The absolute masses of primal cuts of meat in E, I, and II classes were significantly greater in Istrian donkeys than in Littoral Dinaric donkeys (p &lt; 0.01), although the differences in the proportions of primal cuts were not significant. The breed did not have a significant impact on the color, pH, or meat composition. A significant influence of breed on milk yield, lactose, protein, and the fat content of milk was observed (p &lt; 0.01). A significant influence of breed on the ratio of n-6/n-3 PUFA fatty acids in donkey milk was observed (p = 0.002). The values of the atherogenic and thrombogenic indexes were favorable, considering potential beneficial effects of donkey milk and meat on consumer health. The findings of this research suggest that local donkey breeds hold significant potential for meat and milk production, focusing on the uniqueness and quality of their products rather than the quantity of meat and milk they can produce.

Association of polymorphisms in IGF2, CLU and STAT5A genes with milk production characteristics in Chinese Holstein cattle

Reflecting the quality of milk at the molecular level is a frontier technology. The aim of this study was to analyze the polymorphisms of bovine insulin-like growth factor 2 (<i>IGF2</i>), signal transducer and activator of transcription 5A (<i>STAT5A</i>) and clusterin (<i>CLU</i>) genes in the raw milk from 507 Chinese Holstein cow using polymerase chain reaction (PCR)-restriction fragment length polymorphism techniques and to evaluate their correlations with the milk protein content (MPC), milk fat content (MFC), milk lactose content (MLC) and milk total solids content (MTSC). In <i>IGF2</i> gene, genotype GG was the most frequent genotype (51.68%) followed by the genotype GT (38.03%) and TT (10.29%). And the genotype TT of <i>IGF2</i> gene was superior to the other genotypes in MPC. In <i>CLU</i> gene, genotype GG was the most common genotype (63.99%) followed by the genotype GA (34.45%) and AA (1.56%). And the genotype AA of <i>CLU</i> gene had greater MFC and MLC, but lower MTSC than GA genotype individuals. For <i>STAT5A</i> gene, the frequency of genotype CC and CT was similar (45.30% and 45.08%), while the genotype TT had lowest frequency (9.62%). And the genotype TT of <i>STA5A</i> gene had highest MPC and lowest MLC. Thus, screening for the <i>IGF2</i>, <i>CLU</i> and <i>STAT5A</i> genes were available for evaluating milk quality and raw milk samples were graded according to the different genotypes.

Milk Production and Reproductive Performance of Holstein Friesian Dairy Cattle in the Working Area of ​​South Bandung Pangalengan Animal Husbandry Cooperative (KPBS) Bandung Regency

Increasing the population and productivity of dairy cows is one of the way to boost national milk production capacity. This study was aimed to determine and investigate the performance of milk production and reproduction of Friesian Holstein (FH) dairy cows in the Working Area of KPBS Pangalengan, Bandung Regency. This research used FH dairy cows with a complete milk production and reproduction record. In total, there were 90 heads of cows in the Pangalengan District and 178 heads of cows in the Kertasari District. This study used the survey method to collect the data. A Multistage Random Sampling Method was used in this research. Sampling was carried out in two stages, the first stage was sampling from two sub-district locations in Pangalengan and Kertasari Districts. In the second stage, two villages were selected from each district: Pangalengan and Margamukti Villages in Pangalengan District, and Santosa and Tarumajaya Villages in Kertasari District. Farmers and their cows were chosen by simple random sampling. Data on milk production and reproduction records were obtained from farmers and their cows through direct observation and interviews related to the identity of the cattle they owned. The results showed that the average performance of the milk production characteristics of FH dairy cows was: an average milk production of 3779.2±497.48 liters/head/day, an average length of lactation of 307.8±31.30 days, and an average dry period of 72.14±21.43 days. The lactation period had a significant effect (P&amp;lt;0.05) on milk production. The peak of milk production was reached in the fourth lactation period. The mean of reproductive traits consisting of the first postpartum mating was 77±20.5 days, the average length of days open was 96±26.4 days, the average number of services per conception was 1.8±0.85 times, and the average calving interval was 381.05± 24.5 days. In conclusion, FH dairy cows raised in Pangalengan and Margamukti Villages, Pangalengan District, Santosa and Tarumajaya Village, Kertasari District, in the working area of Pangalengan KPBS during the Covid-19 pandemic indicated a fairly good performance of milk production and reproduction characteristics.

Drdof the genotype of HSP70B gene in some characteristics of the components of milk

The study was conducted at Taj Al-Nahrain station in Al- Diwaniyah Governorate, which Is approximately 200 km from the center of Dhi Qar Governorate, for the period from 10/2/2021 to 1/4/2022.And the laboratory part of the study was conducted In the Molecular Genetics Laboratory of the Marshes Research Center at Dhi Qar University. The study includeincludeed 49 Holstein cows Imported in their third productive season, Blood samples were drawn from them for the purpose of separating the genetic material (DNA) from It and studying the heat shock protein HSPA6 gene and knowing Its relationship to milk production characteristics In Holstein cows ,The results showed the nucleotide sequence on the 475bp gene segment extracted from the HSP70B gene the presence of the point mutation G˃T.113 was detected In the third exon of the above gene In the cattle sample under study. And the mutation discovered In the studied piece of the HSP70B gene was a missense mutation and It worked to change the code for the amino acid valine to private code With the amino acid lucine .Three genotypes were shown: GG, GT, and TT. Groups of cows carrying the genotypes (GG, GT and TT) did not differ significantly among themselves in the characteristics of milk components, but an arithmetic superiority between the three genotypes was noticed and referred to in all the studied traits.

Study of the allelic frequency of HSPA6 gene and its genotypes and their effect on some characteristics of milk production in Holstein cows

The study was conducted at the Taj Al-Nahrain cattle station in Al-Diwaniyah Governorate, which is 200 km from the center of Dhi Qar Governorate. For the period from 10/15/2021 to 10/3/2022, 49 Holstein cows imported from Germany were used in this experiment, all in the third production cycle. And the laboratory part of the study was conducted in the laboratory of the Marsh Research Center \ Dhi Qar University for the purpose of separating the genetic material from cow blood samples and conducting genetic analysis on it and extracting the possible genotypes HSPA6 heat shock protein gene. The animals in the station were fed according to the season and the year in terms of the availability of fodder and the percentage of costs involved in raising the cows, as well as on the general state of the productivity of the cows, but in general they are provided with green fodder, which includes jet, barley, corn stalks and a percentage of each of the dry fodder (hay and hay). ) and concentrate (barley, bran and cake) according to what is available from them, as well as limestone and table salt. Data on milk production were collected from the station records, where the milk production was recorded weekly for the morning and evening fenugreek by the station, and the milk components were analyzed in the Abu Dairy Company Gharib / Research and Development Division by Milk Analyzer. 3 ml of blood was collected from the udder vein of each cow by 5 ml medical syringes, suitable for the size of the animal’s vein, and placed in collection tubes containing an anticoagulant substance (K2 EDTA) and transported in a cooler box for safekeeping Freezing at -18°C until extraction time.&#x0D; From the results obtained from this study, we can conclude that the mutation detected in the studied segment of the 6HSPA gene was a type of missense mutation and worked to change the code of the amino acid valine to the code of the amino acid leucine. Three genotypes were shown: GG, GT, and TT. It was found that there was a clear commonality of cows carrying the GG genotype with a rate of 88%, followed by the GT genotype with 8%, while the TT genotype got the lowest percentage and amounted to 4%, and with allelic recurrence Its value is 0.92 for the G allele and 0.08 for the T . allele&#x0D; Groups of cows carrying the genotypes (GG, GT and TT) did not differ significantly among themselves in the characteristics of milk production and its components, but an arithmetic superiority between the three genotypes was observed and referred to in all the studied traits.

Polymorphisms of the IL-17A Gene Influence Milk Production Traits and Somatic Cell Score in Chinese Holstein Cows.

The cow’s milk production characteristics are a significant economic indicator in the livestock industry. Serum cytokines such as interleukin-17 (IL-17) may be potential indicators for bovine mastitis concerning the milk somatic cell count (SCC) and somatic cell score (SCS). The current study aims to find previously undiscovered single nucleotide polymorphisms in the bovine (IL-17A) gene and further investigates their associations with milk production traits in Chinese Holstein cows. Twenty Chinese Holstein cows were randomly chosen from six farms in Jiangsu Province, China. The DNA was extracted from selected samples of bloods for PCR amplification Sequence analyses were used to find SNPs in the bovine (IL-17A) gene. The discovered five SNPs are g-1578A>G, g-1835G>A, and g-398T>A in the 5′UTR; g3164T>C and g3409G>C in the exon region. The genotyping of Holstein cows (n = 992) was performed based on Sequenom Mass ARRAY and SNP data. The connection between SNPs, milk production variables, and the somatic cell score was investigated using the least-squares method. Based on the results, SNP g-398T>A had a significant linkage disequilibrium with g3164T>C. SNPs were found to have significant (p < 0.05) correlations with the test-day milk yield. In conclusion, IL-17A affects cow’s milk production traits significantly.

DRY BREWER GRAINS AS REPLACEMENT FOR ALFALFA IN DIETS FOR LACTATING EWES

The settlement of small and medium breweries in cities leads to the production of nutrient-rich organic residues, the quick decomposition of which causes unpleasant odours and attracts large amounts of flies. Under the hypothesis that replacing alfalfa (lucerne) with dry brewer grains (DBG) for lactating ewes would modify their milk production and physicochemical quality. The aim was to determine the effect of the DBG supplementation in the feed of ewes in milk production and quality, as well as in the physical condition of the animals. Fifteen 18-month-old ewes from a cross between Friesian × Rambouillet resulting from a first birth (30 days on milk) were distributed into 3 treatments with 0, 150 or 300 g of DBG. The experiment had a duration of 30 days, in which milk production, feed intake and physicochemical characteristics of the milk (fat, non-fatty solids, density, cryoscopic point, protein, lactose, and salts) were measured and each week the intake of feed in dry mass and the change in body weight were registered. Milk production displayed no differences between treatments and a decrease was observed in the production of milk for all treatments between weeks one (462 mL) and four (162 mL). Physicochemical variables of the milk displayed no differences between treatments, and quality was not affected. The change in body weight was the highest in the 300 g DBG treatment, with a modification of approximately 12.8 ± 0.45 kg (p ≤ 0.05) during the trial time, daily weight gain was 440 ± 0.08 g d-1 (p ≤ 0.05). The implementation of DBG in the feeds of ewes reduced the intake of dry matter, food conversion improved, and the cost of feed per ewe was reduced by up to 33.8 %.