Milk Production Performance Research Articles

Effects of higher plasma growth hormone levels on subclinical ketosis in postpartum Holstein cows

Abstract Ketosis is a major metabolic disorder that can lead to huge economic losses in postpartum dairy cows by influencing milk production and reproduction performance. Therefore, it is very important to understand the characteristics and significance of plasma GH levels and dynamic changes in postpartum dairy cows for finding pathogenesis of subclinical ketosis (SK). The present study aimed to determine the role of growth hormone (GH) from the onset of SK to the fifth week postpartum and to explain the variations in GH, and metabolic markers namely, β-hydroxybutyric acid (BHBA), non-esterified fatty acid (NEFA) and glucose (GLU) at early and later SK stages in postpartum Holstein cows. A 5-wk test and an intraday 12-h test were conducted in postpartum Holstein cows. Both tests were carried out every three hours from 10:00–22:00 for 7–14 days postpartum (12-h test: n = 16) to determine plasma concentrations of GH, BHBA, NEFA and GLU. The 5-wk test results showed that GH, BHBA and NEFA concentrations were significantly higher in the SK group during the five-weeks postpartum (p < 0.01); GLU concentration was significantly lower in the SK group (p < 0.01). Intraday 12-h test results revealed that the feeding time affected the plasma concentrations of GH, BHBA, NEFA and GLU. After 1-h of feeding time, GH concentrations decreased, while BHBA, NEFA and GLU concentrations increased. After 4-h of feeding time GH, BHBA and NEFA had the highest plasma concentrations, and GLU the lowest. In both experiments, GH was positively correlated with BHBA, NEFA, and negatively correlated with GLU. It can be suggested that GH has a potential role in development and aetiology of subclinical ketosis.

Effects of dietary concentrate to forage ratio on milk performance, milk amino acid composition and milk protein synthesis of lactating donkeys

The purpose of this experiment was to compare the effects of the dietary concentrate-to-forage ratio on lactating donkey milk production performance, milk protein synthesis and milk amino acid composition by replacing part of low-quality roughage with alfalfa. The second objective was to investigate the possible mechanism by which the dietary concentrate-to-forage ratio affects donkey milk protein synthesis. These results will provide a theoretical basis for the rational preparation of feed and optimization of the amino acid composition of donkey milk. This experiment adopted a single-factor randomized trial design. Sixteen Dezhou donkeys with similar ages (6.73 ± 1.16 years), weights (250.84 ± 27.21 kg), parities (3.25 ± 1.12 foals) and lactation days (40 ± 4 days) were selected and evenly (n = 8 per group) divided into a low forage feed group (LF) and a high forage feed group (HF). The LF group was fed a diet with a concentrate to forage feed ratio of 40:60, and the HF group was fed a diet with a concentrate to forage feed ratio of 30:70. The energy and protein levels of the two diets were the same, and the test period lasted 8 weeks. Compared with the LF group, the concentrations of total protein, prolactin and hydrocortisone in the serum of donkeys in the HF group were increased (P < 0.05); the apparent digestibility of dry matter, neutral detergent fiber and energy digestibility and energy metabolic of the donkeys in the HF group were improved (P < 0.05); the concentrations of albumin, epidermal growth factor and urea phosphate tended to decrease (0.05 < P < 0.10); the concentrations of threonine (Thr), lysine (Lys), methionine, histidine, proline and limiting amino acids (LAAs) in the plasma and nitrogen metabolism of the donkeys in the HF group were increased (P < 0.05); milk yield, production and synthesis efficiency of milk protein and most amino acid (AA) production in milk (except serine and valine) were increased (P < 0.05); the proportions of Thr, Lys phenylalanine and LAA in donkey milk were increased (P < 0.05); the final body weight and the body weight gain of donkey foals in the HF group was improved. Under the condition of feeding the same energy and nitrogen levels, increasing the proportion of forage from 60% to 70% by replacing part of low-quality forage with alfalfa promoted the protein and energy metabolism, increased milk protein synthesis efficiency, milk production efficiency and milk production performance, improved the proportion of LAAs and optimized the AA composition of donkey milk.

Herd level economic comparison between the shape of the lactation curve and 305 d milk production.

Herd milk production performance is generally evaluated using the herd's average 305-day milk production (HM305). Economic comparisons between herds are also often made using HM305. Comparing herds is thus based on summarized milk production, and not on the form of the lactation curves of the cows within the herd. Cow lactation curve characteristics can be aggregated on a calendar year basis to herd lactation curve characteristics (HLCC) (herd magnitude, herd time to peak yield and herd persistency). Thus far, no literature has evaluated whether the shape of the lactation curve (described by HLCC) is better able to explain the economic variation of herds than summarized milk production such as HM305 does. This study aims to determine whether HM305 or HLCC is better able to explain the variation in economic performance between herds. To do so, we evaluated 8 years of Dutch longitudinal data on milk production and the financial accounts of 1,664 herds. Cow lactation curve characteristics were calculated through lactation curve modeling and aggregated to HLCC on a calendar year basis for two parity groups (primiparous cows and multiparous cows). Using income over feed cost per cow (IOFC-cow) or per 100 kg milk (IOFC-milk) as the dependent variable separately, we developed four linear mixed models. Two models were used to analyse the association between herd economic performance and HLCC; the other two models were used to analyse the association between herd economic performance and HM305. A Cox test and J test were used to compare two non-nested models to investigate whether HM305 or HLCC better explain IOFC. The average IOFC-cow was €2,305 (SD = 408) per year, while the average IOFC-milk was €32.1 (SD = 4.6). Results showed that HLCC and HM305 explain the same amount of variance of IOFC-cow or IOFC-milk. IOFC-cow was associated with HM305 and HLCC (except herd time to peak yield for primiparous cows). Herd magnitude was most strongly associated with IOFC-cow, followed by herd persistency and herd time to peak yield of multiparous cows. IOFC-milk was not associated with HM305 or HLCC (except for a weak negative association with herd persistency for primiparous cows). IOFC-cow and IOFC-milk were driven most by time effects. In conclusion, HLCC and HM305 explain the same amount of variance in IOFC-cow or IOFC-milk. HLCC is more computationally expensive, while HM305 is more readily available.

The effect of ensiled paulownia leaves in a high-forage diet on ruminal fermentation, methane production, fatty acid composition, and milk production performance of dairy cows

BackgroundThe use of industrial by-products rich in bioactive compounds as animal feeds can reduce greenhouse gas production. Paulownia leaves silage (PLS) was supplemented to dairy cows' diet and evaluated in vitro (Exp. 1; Rusitec) and in vivo (Exp. 2, cannulated lactating dairy cows and Exp. 3, non-cannulated lactating dairy cows). The study investigated the PLS effect on ruminal fermentation, microbial populations, methane production and concentration, dry matter intake (DMI), and fatty acid (FA) proportions in ruminal fluid and milk.ResultsSeveral variables of the ruminal fluid were changed in response to the inclusion of PLS. In Exp. 1, the pH increased linearly and quadratically, whereas ammonia and total volatile fatty acid (VFA) concentrations increased linearly and cubically. A linear, quadratic, and cubical decrease in methane concentration was observed with increasing dose of the PLS. Exp. 2 revealed an increase in ruminal pH and ammonia concentrations, but no changes in total VFA concentration. Inclusion of PLS increased ruminal propionate (at 3 h and 6 h after feeding), isovalerate, and valerate concentrations. Addition of PLS also affected several populations of the analyzed microorganisms. The abundances of protozoa and bacteria were increased, whereas the abundance of archaea were decreased by PLS. Methane production decreased by 11% and 14% in PLS-fed cows compared to the control in Exp. 2 and 3, respectively. Exp. 3 revealed a reduction in the milk protein and lactose yield in the PLS-fed cows, but no effect on DMI and energy corrected milk yield. Also, the PLS diet affected the ruminal biohydrogenation process with an increased proportions of C18:3 cis-9 cis-12 cis-15, conjugated linoleic acid, C18:1 trans-11 FA, polyunsaturated fatty acids (PUFA), and reduced n6/n3 ratio and saturated fatty acids (SFA) proportion in milk. The relative transcript abundances of the 5 of 6 analyzed genes regulating FA metabolism increased.ConclusionsThe dietary PLS replacing the alfalfa silage at 60 g/kg diet can reduce the methane emission and improve milk quality with greater proportions of PUFA, including conjugated linoleic acid, and C18:1 trans-11 along with reduction of SFA.Graphical Graphical abstract of the experimental roadmap

Coupling genetic and mechanistic models to benchmark selection strategies for feed efficiency in dairy cows: sensitivity analysis validating this novel approach

Coupling genetic and mechanistic models is appealing to explore the impact of energy trade-offs on the expression of feed efficiency traits in dairy cattle and predict selection response. The objective of this study was to evaluate the sensitivity of genetic (co)variances among milk production and feed efficiency (FE) traits simulated with a mechanistic dairy cow model depending on the genetic variability assumed for input parameters. The cow model was calibrated for a grass-based production and included a genetic module. Four genetically driven input parameters described the energy acquisition and allocation to different biological functions of cows. In each simulation, a population of 20 000 cows from 200 unrelated sires was simulated. The nutritional environment was an input of the model and was tailored by modulating feed offer and quality. A non-limiting nutritional environment was simulated to mimic a situation of ad libitum feeding and was used as a reference. Two other scenarios were simulated by imposing a moderate and a high DM intake restriction on simulated cows. Five phenotypes related to milk production and FE were considered: milk production, BW at calving, DM intake, lactation efficiency and body reserves during early lactation. These traits were estimated both in first and third lactations. A baseline scenario was defined considering a heritability of 0.35 and a phenotypic CV of 10% for acquisition and allocation parameters (AAPs). Different scenarios were explored by reducing the heritability to 0.15 or increasing CV to 20 and 30% or both. Heritabilities and genetic correlations between simulated traits were estimated using animal linear mixed models. Each scenario was replicated 20 times. Simulated performance and genetic parameters for these traits were compared across scenarios using an ANOVA. The heritability of AAPs only influenced the heritability of simulated traits. The phenotypic CV of AAPs mainly influenced the variability of simulated traits. However, increasing the CV also affected the number of cows reaching first and third lactation, due to the early culling of females with extreme AAPs profiles. Compared to other input parameters, the nutritional environment had the largest effect on both performance and genetic correlations between traits. Using a heritability value of 0.35 and a CV of 10% for all four AAPs enabled the simulation of milk production and FE performance with a realistic mean, variance and genetic correlations among traits in the three considered environments.

The relationship of negative energy balance (NEB) and energy metabolism, milk production and reproductive performance during early lactation in dairy cows in Heilongjiang, China

Negative energy balance (NEB) causes economic losses to dairy farms around the globe. The aim of this study was to investigate the effect of NEB on energy metabolism, reproduction, etc. during early lactation in dairy cows on intensive farms in Heilongjiang, China. According to β- hydroxybutyric acid (BHBA), glucose (GLU), Non-esterified fatty acid (NEFA) levels, and clinical manifestations 14-21 days postpartum, 118 cows were divided into a positive energy balance (PEB) group (BHBA&lt;1.2, GLU&gt;2.8, NEFA&lt;0.7 mmol/L, n=67) and an NEB group (BHBA&gt;1.2, GLU&lt;2.8, NEFA&gt;0.7 mmol/L, n=51). These indicators were analyzed by cross-sectional research methods combined with Pearson correlation analysis and a prospective cohort study. The results showed that at 14-21 days postpartum, compared with the PEB, the body condition score, body condition loss (BCL), milk urea nitrogen, BHBA, NEFA, the interval from calving to first estrus (ICFE), pregnancy per artificial insemination (P/AI), and calving interval were higher (P&lt;0.05), and daily lactation (DL), milk protein and GLU, estrus rate and conception rate were lower in NEB cows. BCL was positively correlated with ICFE and P/AI (P&lt;0.05), and negatively correlated with estrus and conception rate (P&lt;0.05). DL was negatively correlated with the P/AI (P&lt;0.05). There was a positive association between NEB and anestrus (χ2 M-H=12.63, P=0.0004), the risk of anestrus caused by NEB rose by 3.67 times that of PEB. The conclusion showed that NEB is closely related to BCL, which is a factor in the decline of lactation and reproductive performance in dairy cows. NEB is a risk factor for anestrus in dairy cows.

Review on milk production performance, challenges, and opportunities of dairy cows production in oromia regional state, Ethiopia

This review was conducted to review the information on milk production performance, challenges, and opportunities of dairy cattle production in Oromia. Supported management practices, marketing situations, feed sources, and feeding systems the foremost milk production systems are identified as rural milk production, peri-urban, and concrete milk production. Ethiopia holds large potential for dairy development mainly thanks to an acceptable environment and large cattle number that contains 65.35 million cattle populations. While there is a large milk cow population and favorable climatic conditions, self-sufficiency in milk production is low. The mean values of daily milk yield (DMY) range from 1 to2.8 liter/day with lactation length (LL) of 6.78 to 9.13 months for indigenous breeds, 6.5 to fifteen liters/day with lactation length of 7.52 to 11.67 months for crossbreed cows respectively. Both DMY and LL were significantly stricken by breed, parity, and year of calving. Challenges for dairying vary from one location to a distinct one. The foremost challenge that affects milk production performance of cattle in Oromia includes feed shortage, high feed cost, land shortage for farming of improved forage, insufficient veterinary services, no operational breeding strategy and policy, and low productivity of the indigenous cattle breeds are the foremost important factor limiting dairy products within the region. Therefore, to enhance these milk production performances of the dairy cow to determine genetic improvement policy, strategy, and breeding program and implement well management practices.

Effect of milking environment enrichment through music on production performance and behaviour in cattle.

Enrichment of milking environment through music has been proposed to help animals to cope with divergent stressors. In sight of the above, a study was conducted to evaluate the effect of Indian instrumental music-based environmental enrichment played in yaman raga on milk production performance and behaviour in cattle. A total of 21 lactating dairy cattle (Vrindavani crossbred cows) having similar parity and stage of lactation were selected in three groups - T1, T2 and T3, each consisting of seven animals. The T1 and T2 groups were exposed to instrumental flute and sitar, respectively, 10min prior to the start of milking and continued till completion of milking; while the T3 group served as control. Musical enrichment of the environment was done using recorded-tape of flute and sitar was played in yamen raga at 40-60 (dB) decibel intensity. The results revealed a non-significant difference in milk yield, rectal temperature, respiration rate, T3 (triiodothyronine) and T4 (thyroxine) hormones. However, there exhibited a significant (p < 0.05) difference in milking time, milking speed, cortisol hormones and behavioural parameters such as milk let-down in the animals exposed to music compared to the control group. Thus, the results have significant implications relating to the behavioural fitness and welfare of dairy animals and reducing residual milk.

Influence of human capital on the performance of organic milk production

Over the past decade, a growing interest of consumers in the consumption of organic milk has been recognized, mostly because of its positive effect on human health, besides other various positive effects. The main goal of organic milk production is to bring agricultural production in close alignment with the requirements of a sustainable system. Human capital in organic farming is an important factor as it significantly influences production and financial results. As an important factor in the production, socio-economic characteristics of producers considerably determine possibilities of the future development of this system of production in a certain country. Focusing on the aspect of human capital, this paper examines the possibilities of the development of organic agricultural production in the Republic of Serbia. The research has been conducted on the territory of Serbia on individual farms which are certified for organic farming. Following the findings, the authors conclude that human capital in organic milk production of the Republic of Serbia does not represent a limiting factor in the future development of this system and that human capital in terms of learning and education, experience and expertise, innovation and creativity, and sources of knowledge has a positive relationship with the business performance.

Replacing the Concentrate Feed Mixture with Moringa oleifera Leaves Silage and Chlorella vulgaris Microalgae Mixture in Diets of Damascus Goats: Lactation Performance, Nutrient Utilization, and Ruminal Fermentation.

Simple SummaryMoringa oleifera and Chlorella vulgaris microalgae have a good balance of amino acids with high protein contents; however, complementary and synergic effects between proteins can improve their nutritive value compared to the individual additive. Replacing a concentrate mixture at 20% to 40% levels with a mixture of M. oleifera and microalgae improved nutrient digestibility, ruminal fermentation characteristics, milk production, composition and the fatty acid profile of goats. Inclusion of M. oleifera and microalgae mixture to partially replace concentrates may enhance milk production performance and milk quality without affecting animal health.Exploring suitable alternatives for high-cost concentrate feeds is a critical factor for successful livestock production. The present experiment aimed to evaluate the dietary inclusion of Moringa oleifera silage and Chlorella vulgaris microalgae (at 1% of total diet, DM basis) in a quintuplicate 3 × 3 Latin square design for milk production performance, nutrient utilization and ruminal fermentation in Damascus goats. Fifteen lactating Damascus goats were divided into three groups to be fed a diet composed of a concentrate mixture and rice straw at 60:40 (DM basis) in the control group and fed for 30 days in each period. The concentrate mixture in the control treatment was replaced with M. oleifera silage and C. vulgaris microalgae at 20% (MA20 treatment) or 40% (MA40 treatment). Treatments did not affect total feed intake but increased (p < 0.01) crude protein (CP) and fiber intakes while decreasing nonstructural carbohydrates intake. The digestibility of CP and acid detergent fiber increased due to silage supplementation compared to the control treatment. Treatments increased (p < 0.05) ruminal pH and the concentrations of total volatile fatty acids, acetate, and propionate; however, they decreased (p < 0.05) the concentrations of ammonia-N. Treatments increased (p < 0.05) the concentrations of serum glucose and antioxidant capacity. Both MA20 and MA40 treatments increased the daily milk production, the concentrations of milk fat and lactose, and feed efficiency compared to the control treatment. Additionally, MA20 and MA40 treatments increased the proportions of total polyunsaturated fatty acids and total conjugated linoleic acids. It is concluded that the concentrate feed mixture in the diet of lactating goats can be replaced up to 40% (equals to 24% of total diet) with M. oleifera silage to improve feed intake and nutrient utilization, and milk production performance.

Growth rates of contract-reared versus home-reared replacement dairy heifers

Successful heifer rearing is dependent on achieving optimal average daily gain (ADG) targets to calve for the first time at 24 months. Whilst dairy farmers internationally have traditionally managed their heifers on-farm to achieve these targets, recent dairy herd expansion within Europe has resulted in increased demand for labour-saving heifer-rearing strategies, such as off-farm contractrearing. However, loss of direct influence on the day-to-day management decisions affecting the ability of heifers to grow adequately to achieve this age of first calving may represent a potential barrier to uptake. Hence, the aim of this longitudinal observational study was to compare the growth rates of contract- vs home-reared heifers. Approximately 6 500 heifers from 120 commercial Irish dairy farms were enrolled in a 3-year study. For 65 of these farms, heifers were reared at a contract-rearing facility. For the remaining 55 farms, heifers were reared on their home farm. Over the course of 20 months from birth until precalving, heifers were examined and weighed at four farm visits. The relationship between several independent variables (farm type, herd size, heifer breed, economic breeding index (EBI) and health events) and ADG at different time points was investigated and analysed utilising linear mixed models. Overall ADG for heifers throughout the rearing period was 0.71 kg/day. There was a significant association between farm type and ADG for all five linear ADG models; home-reared heifers grew, on average, 0.025, 0.039, 0.11 and 0.059 kg/day more than contract-reared heifers between visit 1 and visit 4 (overall ADG), visit 1 and visit 2, visit 2 and visit 3 and visit 1 and visit 3, respectively. The occurrence of diarrhoea during farm visit 2 (median age 8.5 months) was associated with a significant reduction in ADG between visit 3 and visit 4. Calf-hood disease (diarrhoea, respiratory disease or navel ill) was not associated with the growth rate during any of the subsequent visit periods. While home-reared heifers had greater ADG during four of the five periods studied, median heifer ADG in both cohorts exceeded the minimum published target weight gains at each developmental stage required for heifers to reach puberty, conceive at 15 months and calve for the first time at 24 months. Importantly, there was wide variation both within enterprises and between farms. It was concluded that while the absolute difference in daily growth rates of home- and contract-reared heifers was minimal, when considered in the context of the entire heifer-rearing period, these growth rate differences have the potential to impact the future reproductive and milk production performance of heifers.

Novel Insight Into the Role of ACSL1 Gene in Milk Production Traits in Buffalo.

Understanding the genetic mechanisms underlying milk production traits contribute to improving the production potential of dairy animals. Long-chain acyl-CoA synthetase 1 (ACSL1) plays a key role in fatty acid metabolism and was highly expressed in the lactating mammary gland epithelial cells (MGECs). The objectives of the present study were to detect the polymorphisms within ACSL1 in Mediterranean buffalo, the genetic effects of these mutations on milk production traits, and understand the gene regulatory effects on MGECs. A total of twelve SNPs were identified by sequencing, including nine SNPs in the intronic region and three in the exonic region. Association analysis showed that nine SNPs were associated with one or more traits. Two haplotype blocks were identified, and among these haplotypes, the individuals carrying the H2H2 haplotype in block 1 and H5H1 in block 2 were superior to those of other haplotypes in milk production traits. Immunohistological staining of ACSL1 in buffalo mammary gland tissue indicated its expression and localization in MGECs. Knockdown of ACSL1 inhibited cell growth, diminished MGEC lipid synthesis and triglyceride secretion, and downregulated CCND1, PPARγ, and FABP3 expression. The overexpression of ACSL1 promoted cell growth, enhanced the triglyceride secretion, and upregulated CCND1, PPARγ, SREBP1, and FABP3. ACSL1 was also involved in milk protein regulation as indicated by the decreased or increased β-casein concentration and CSN3 expression in the knockdown or overexpression group, respectively. In summary, our present study depicted that ACSL1 mutations were associated with buffalo milk production performance. This may be related to its positive regulation roles on MGEC growth, milk fat, and milk protein synthesis. The current study showed the potential of the ACSL1 gene as a candidate for milk production traits and provides a new understanding of the physiological mechanisms underlying milk production regulation.

Association analysis for SNPs of MSTN and IGFBP-3 genes with body size and other production traits in Liaoning Cashmere Goats

Liaoning cashmere goat (LCG) have tall bones, high cashmere production and outstanding meat production performance. In recent years, good breeding progress has not been made in terms of body size, meat yield, milk yield and other properties in terms of production. The study focused on the correlation between the SNPs of MSTN and IGFBP-3 genes with the body size performance, cashmere production and milk performance. The MSTN and IGFBP-3 gene sequence alignment and PCR-Seq polymorphism were used to detect the potential SNPs, and the correlation with production performance was analyzed by SPSS and SHEsis software. The results showed that the TT genotype at the T1662G locus of the MSTN gene is dominant and has significant advantages in body measurements such as sacrum height, chest width, and waist height. The C allele at the C4021T locus of IGFBP-3 gene shows an advantage in the body measurement performance. Among the haplotype combinations, H2H2:TGTC is preponderant combination for body size performance, H2H2:TGTC and H1H2:TGCC are preponderant combinations for cashmere production performance, H1H3:GGCC is preponderant combination for milk production performance. It may be a molecular marker for future selection and breeding.

Factors affecting fertility traits and milk yield of Holstein cattle with different origins raised in Trakya region

This study was conducted with Holstein heifers imported from the United States (US), Germany, and the Czech Republic to a private dairy farm in Kırklareli/Lüleburgaz region in Turkey to evaluate their adaptation in terms of milk production and fertility performance. The first insemination age of the herd was 490.62 days, and the first calving age was 804.24 days. The number of inseminations required per pregnancy was calculated as 3.99, gestation length as 279.72 days, and service period as 213.99 days. The rate of abortion and twin births were higher in those of US origin. Increased first calving age was observed in heifers of German origin due to delayed insemination. The mean actual lactation milk yield in the first lactation periods was 11834.75 Lt, 305 days milk yield was 8573.31 Lt, lactation length was 419.61 days, the dry period was 63.02 days. Milk yield performance of Holsteins of US origin was higher in the first lactation period. In conclusion, milk production was profitable; however, the fertility performance of the herd was poor in general. Poor fertility performance was due to poor herd management and adaptation problems. Therefore, after the calving period, more attention should be paid to oestrus monitoring and insemination activities. In Turkey, the success of live animal imports should be well investigated; in particular, problems occurring during animal selection for importation should be evaluated, and short-/long-term national strategies should be developed.

Association analysis of single-nucleotide polymorphism in prolactin and its receptor with productive and body conformation traits in Liaoning cashmere goats.

The results of this study showed that the single-nucleotide polymorphism (SNP) sites of the PRL and PRLR genes have a certain association with the milk production performance, body size and cashmere performance of Liaoning cashmere goats (LCGs). Through our designed experiment, the potential SNPs of LCG were detected by sequence alignment, and two SNPs were found on two genes. The CC genotype of the PRL gene is the dominant genotype among the three genotypes. The GG genotype of the PRLR gene is the dominant genotype among the two genotypes. At the same time, the two genotypes also have good performance in cashmere production and body size. Through the screening of haplotype combination, the milk fat rate 7.6 %, the milk protein rate 5.6 %, the milk somatic cell number 1500 10 mL, the cashmere fineness 15.75 m, the chest girth 105 cm, the chest depth 33 cm, and the waist height 67.5 cm are considered as screening indexes for comprehensive production performance of Liaoning cashmere goats. It is concluded that the GCGC type is the dominant haplotype combination. According to our research data, we found that the biological indicators of Liaoning cashmere goat milk are higher than the national standards, so we think it is very significant to study the milk production performance of our experiment. Further research can be done on goat milk production and body conformation traits around PRL gene and PRLR gene.

Non-genetic factors affecting phenotypic parameters of milk production and reproductive performance in lactating Egyptian buffaloes

Non-genetic factors affecting phenotypic parameters of milk production and reproductive performance in lactating Egyptian buffaloes

Effect of feed supplementation through multi nutrient feed block (MNFB) on milk production, composition and reproductive behaviour of buffaloes (Bubalus bubalis) – A field study in Arid Rajasthan

The Buffalo rearing is adopting faster rate in arid region of Rajasthan due to its multifaceted utility for both milk and meat. Despite of better management practice are adopted for buffaloes, they also depend upon grazing and poor quality of fodder to meet out their total dry matter intake. The concept of balanced feed with respect to mineral and vitamins are not aware by farmer’s community. Thus, the alternative low cost balanced feed was adopted in buffaloes under field condition to augment the milk production with optimum reproductive efficiency. MNFB was developed at feed technology unit of CAZRI, as solidified block of wheat bran, guar meal, dolomite, -minerals and vitamins mixture powder, salt, molasses and urea solution. The study evaluated feeding effect of multi-nutrient feed block on milk production and reproduction performances of lactating buffaloes. The Buffaloes under treatment were divided randomly into two groups and assigned to two dietary treatments under village condition. After calving, all the buffaloes in treatment group were dewormed with albendazole 3 gms and feeding of MNFB 2 blocks (2 kgs each)/week for 3 months during March to May. The control group received diet containing bajara (Pearl millet) kuti, dry grasses, crushed cotton and til (sesame) cake. Milk production, peak milk yield were increased highly significant. Fat percentage was significantly increased. All Observations were monitored as per format. In reproductive performances were like sign of oestrus, conception and post partum reproductive complication 90%, 86.6% and 0.06% in treatment group and 70%, 60% and 30% in Control group respectively. It was concluded that MNFB feeding improved milk yield, milk fat, general health status and reproductive performance of buffalos, as it is a good source of protein, energy, and minerals. It is recommended that MNFB should be used as a supplementation in lactating buffaloes when they area fed with low quality fodder in arid and semi arid region.

Environmental Assessment of Austrian Organic Dairy Farms With Closed Regional Production Cycles in a Less Favorable Production Area

Extensive dairy production in less favorable production areas has a long tradition in Austria. Nevertheless, dairy production also contributes considerable environmental impacts (EIs), e.g., greenhouse gas emissions, nutrient losses, and land use. Therefore, 20 organic dairy farms located in the Lungau region in Austria were assessed concerning their EIs via life cycle assessment (LCA). Cumulative exergy demand (CExD), normalized eutrophication potential (EP), aquatic ecotoxicity potential (AE), and global warming potential (GWP) were considered as impact categories to describe the farms' EIs. The farms were part of a pilot project aiming to produce high-quality dairy products and keep production cycles closed within the project region. Consequently, the purchase of key off-farm resources was only possible within the project region. We adapted existing life cycle inventories to account for those regional resource purchases. Subsequently, the EIs of the 20 farms were related to the functional units (FUs) of 1 kg energy-corrected milk (ECM) and 1 ha agricultural area for milk production and compared to a representative model dairy farm (MDF) that was created based on statistical data and average production values of organic Austrian dairy farms. Compared to the MDF, results show an ~58% lower EP per ha and 44% per kg ECM of the Lungau farms. Further, the CExD per ha was about 24% lower due to a lower use of resources caused by the lower production intensity of the Lungau farms. Regarding GWP, Lungau farms are favorable considering 1 ha as the FU, whereas the MDF seems advantageous if 1 kg ECM is used as the FU. However, caused by a high variation of purchased roughage and the lower production intensity, the Lungau farms cause higher AE, regardless of the FU. Overall, we identified three principal production parameters determining the environmental performance of milk production in a closed production cycle in a less favorable area, namely, (1) the stocking rate, (2) the fed concentrate, and (3) the purchased roughage. Using those inputs at moderate intensity, the extensively managed Lungau farms can competitively contribute to producing food, thus highlighting the importance of site-adapted agriculture.

Effect of Season Year Milk Production in Different Breeds of Dairy Cows in Badghis Province

The experiment was conducted on three breeds the total 30 breeds of dairy cows and the number of animal of different breeds was 10 holistan, 10 garai and 10 Cross-bred (CB) during 2019 and 2020. The objective of this study was to know the impact of seasonal on milk production performance of Holistan, Garsi and CB or doragh. The average highest seasonal milk production of Garsi and CB was in spring and summer season, 9.22 and 9.02 liter, respectively and Holistan was highest in spring and summer season (8.261 liter), respectively. The overall average milk production of CB, Holistan and Garsi were 8.86, 7.98 and 7.37 respectively. The seasonal variation and milk production performance of all three breeds were found highly significant. Because the other season production was low. The average milk production of 2470 ± 37 L milk production in spring season followed by 2427 ± 41 L in summer and lowest in winter, as 2403 ± 82 L respectively. The average milk production of Garsi breed in different seasons was estimated and it was noticed that the highest average of 2460 ± 35 L milk production in spring season followed by 2434 ± 14 L in summer and lowest in winter, as 2413 ± 62 L respectively. The average milk production of CB Doragh breed in different seasons was estimated of 2540 ± 35 L milk production in spring season followed by 2457 ± 25 L in summer and lowest in winter, as 2432 ± 20 L respectively.

Developmental programming: prenatal and postnatal consequences of hyperthermia in dairy cows and calves

With global warming, the incidence of heat stress in dairy cows is increasing in many countries. Temperatures outside the thermoneutral zone (heat stress) are one of the environmental factors with the greatest impact on milk production and reproductive performance of dairy cows. In addition to several biological mechanisms that may contribute to the effects of fetal programming, epigenetic modifications have also been investigated as possible mediators of the observed associations between maternal heat stress during late gestation and performance and health later in life. In utero programming of these offspring may coordinate changes in thermoregulation, mammary gland development, and milk production ability at different developmental stages. This review examines the effects of prenatal and postnatal hyperthermia on the developmental outcomes of dairy cows, as well as the physiological and molecular mechanisms that may be responsible for the negative phenotypic consequences of heat stress that persist throughout the neonatal and adult periods and may have multigenerational implications. The physiological and molecular mechanisms underlying the negative phenotypic consequences of heat stress are discussed. Research challenges in this area, future research recommendations, and therapeutic applications are also discussed. In summary, strategies to reduce heat stress during the dry period should consider not only the productivity of the pregnant cow but also the well-being of the newborn calf.