Milk Production Of Cows Research Articles

Milk production and composition in warm-climate regions: a systematic review and meta-analysis.

Milk production is a key component of the agriculture sector in the tropics and subtropics, contributing 47.32% to global milk production. This study aimed to quantify milk production and composition (fat and protein) in warm-climate regions located between 30 degrees north and south of the equator. A meta-analysis was conducted using the standardized mean (SM) for milk production, fat percentage, and protein percentage, all adjusted for dry matter intake (DMI), focusing on lactating ruminants. A total of 42, 11, 15, and 16 research papers were selected for cows, buffalo, sheep, and goats, respectively, encompassing 2421 animal records from experiments published between 1992 and 2024. The SM for milk production was 10.38, 9.77, 0.79, and 1.13kg/day/animal for cows, buffalo, sheep, and goats, respectively. Due to the significant variance between different cow breeds, the study divided the cows into three main groups based on breed type crossbreds, foreign, and local breeds. The SM for milk production per animal was 11.49kg/day for crossbreds, 22.95kg/day for foreign breeds, and 7.13kg/day for local breeds. The effect of DMI on the SM of milk production for cows, sheep, and goats was highly significant. For milk fat, the SM was 3.95, 6.64, 4.70, and 3.56% for cows, buffalo, sheep, and goats, respectively. Regarding milk protein, the SM was 3.36, 3.91, 4.34, and 3.45% for cows, buffalo, sheep, and goats, respectively. The results of this meta-analysis highlight that warm-climate regions are significant contributors to global dairy production. Furthermore, improving ruminant milk production and quality in hot climates need further efforts.

Lactation curves for milk, fat and protein in dairy cows under regenerative versus conventional farming practices

ABSTRACT Regenerative agriculture aims to utilise more diverse pasture species and enhance animal performance through sustainable soil management and pasture quality. This study evaluated the influence of regenerative and conventional farming on dairy cow performance and milk production under different pasture mixes and management strategies. Monthly herd test records were used to model individual lactation curves for daily milk, fat, and protein yield for the 2022–2023 season using random regression with third-order orthogonal polynomials. Total yields were calculated from predicted daily yield. Treatments were SPCM: Standard pasture under conventional management, DPCM: Diverse pasture mix under conventional management, and DPRM: Diverse pasture mix under regenerative management. Total milk yield was similar across treatments, averaging 3370 kg (SPCM), 3649 kg (DPCM), and 3626 kg (DPRM) for the 2022–2023 season. No significant differences were observed in fat, protein, milk solids yield, or milk composition. Cows on diverse pastures, regardless of management approach, showed heavier liveweights than those on standard pastures. DPCM and DPRM cows averaged 474 kg, significantly greater than SPCM cows at 464 kg (P < 0.0001), likely due to longer grazing rotation and higher post-graze mass. These findings suggest that pasture species diversity, regardless the management, enhances liveweight without affecting milk composition.

Environmental Footprints of Yogurt Production: A Case Study of a Small-Scale Manufacturing Process in Sri Lanka

This study investigated the life cycle environmental impacts of yogurt production from cradle to gate at the Pulathisi milk factory in Polonnaruwa, Sri Lanka. The functional unit considered was one kilogram of yogurt produced in the factory using existing technology. The defined system boundary encompassed raw milk production and transportation, machinery fabrication, standardization of milk, and standard unit operations of yogurt production. Material and energy usage data were collected through a series of observations, literature and Ecoinvent 3.7.1 databases. The ReCiPe 2008 method was employed for impact analysis, considering eighteen impact categories with SimaPro software. The inventory analysis included material consumption for machinery fabrication, energy consumption, and emissions for each unit operation in yogurt production. Results were characterized using midpoint indicators, and normalized impacts were calculated. The characterized outcomes of the yogurt production process contributed 2.48 kgCO2eq to climate change, 0.0297 kgSO2eq to acidification, 0.0002 kgPeq to eutrophication, and 6.9199 kg 1,4-DBeq to human toxicity. The study identified hotspots, emphasizing the significant contributions of cow milk production and electricity usage to environmental impacts. Potential mitigations, such as improved waste management in dairy farming and switching to renewable energy sources, are proposed to address these impacts. The normalized impacts provided insights for decision-makers and stakeholders to compare environmental performances and guide sustainable practices in yogurt production. The total impact was recorded as 0.014-person equivalent per year per one kilogram of yogurt.

Genetic Evaluation of Monthly Test-Day Milk Yields of Jersey Crossbred Cattle Under Farmers' Production System in Tamil Nadu, India.

Tamil Nadu, a state in southern India, is bereft of any native dairy or dual-purpose cattle breeds, and the state depends chiefly on crossbred cattle for milk production. Jersey crossbred cattle account for 90% of the state's milk production. This genetic evaluation study aimed to assess milk production traits, including test-day milk yields (TDMYs), total lactation milk yield (TMY), and 305-day milk yield (305MY), in these cattle reared under farmers' conditions. Data on monthly TDMYs (TDMY1 to TDMY10) of Jersey crossbred cows (n = 75,627) reared by the farmers over 11 years (2012-2022) were collected for evaluation. The influence of non-genetic factors viz., location (agroclimatic zones), period and season of calving, and parity on TDMYs, TMY and 305MY were assessed, and the variance and covariance components for genetic parameters (heritability and genetic correlation) of the traits were estimated by the method of restricted maximum likelihood (REML) under a multivariate animal model and by a random regression model (RRM). The overall means of various TDMYs ranged from 4.98 (TDMY10) to 9.95 kg (TDMY2), and for TMY and 305MY, the means were 2480.33 and 2393.71 kg, respectively. The heritabilities estimated by the multivariate animal model for TDMYs were moderate and ranged from 0.26 ± 0.02 to 0.37 ± 0.02 and the estimates were less variable throughout lactation, while the estimates obtained by RRM were medium to high and ranged between 0.29 ± 0.01 and 0.67 ± 0.02 for milk yield on day 5 to 305 (DIM 5-DIM 305). The heritabilities estimated for TMY and 305MY were 0.43 ± 0.02 and 0.43 ± 0.02, respectively. The estimates of heritability for mid-lactation yields were comparatively less than those at the beginning and the end of lactation. The moderate to high estimates of heritabilities for TDMYs, TMY, and 305MY obtained in the present study offer ample scope for improving milk production through selective breeding. Genetic correlations between TDMYs estimated by the multivariate animal model were positive and high, with a range between 0.75 ± 0.03 and 0.99 ± 0.00. Considerably higher estimates (0.98-0.99) were observed between adjacent TDMYs showing strong genetic associations. By RRM, genetic correlations estimated between DIMs were positive (except for DIM 5 with DIM 125 to DIM 185 and DIM 125 with DIM 305), and the magnitude of genetic correlation decreased with an increase in the interval between the DIMs. The high genetic correlation observed between the TDMYs (in the early stage of lactation) and total lactation milk yield suggested that these test-day yields could be used favorably for the early selection of cows for milk production, which facilitates reduction in the generation interval and consequently increases the annual genetic gain for the milk production traits.

Effect of Supplementation of Buffer salt on Milk Production in Dairy cows

Effect of Supplementation of Buffer salt on Milk Production in Dairy cows

Protected fats in feeding of highly productive cows

Highly productive animals experience energy deficiency at the beginning of lactation up to 30 % of their energy needs, since cows spend more energy on milk production than they intake with feed. Therefore, to maintain a high level of productivity and minimize live weight loss of cows, it is necessary to increase the energy supply of rations. For these purposes, along with the use of high-quality feed and a decrease in the proportion of starchy grain concentrates in the ration structure, various types of fats are used in feeding of cows, since their energy value is more than 2 times higher than proteins and carbohydrates. The purpose of the research was to study the eff ectiveness of using protected vegetable fats in feeding of highly productive lactating cows. Comprehensive studies were carried out to investigate the effectiveness of using new protected vegetable fats: hydrogenated (Ultra Feed F) and fractionated (Extra Feed F) in feeding of highly productive lactating cows and an assessment of the effectiveness of their use was given. It was recommended as a result of the research that in order to ensure milk productivity of cows at a level of more than 7000 kg of milk (7000–9000 kg), livestock farms should ensure the concentration of metabolic energy in the dry matter of the ration of at least 10.7 MJ/kg, with possible compensation for the deficit in the level of metabolic energy up to 11.0 MJ/kg with protected vegetable fats of domestic production (fractionated Extra Feed F and hydrogenated Ultra Feed F) in the amount of 300 g/head/day during the period of 21–120 days of lactation.

Effects of Oregano Aromatic Water (Oreganum onites L.) Supplementation on Diets of Lactating Dairy cows on Milk Production Performance, Metabolic Health and Antioxidative Defense Mechanism

This study aimed to validate the effect of oregano aromatic water (OAW) on blood parameters, oxidative stress, and production and composition of milk when used as a feed additive. Thirty lactating Holstein cows (average 570 kg), average 74 days in milk and 2.44 lactation number, were randomly divided into three groups for a period of 60-days. These groups included: (G1) control ration, (G2) control ration + OAW (10 mg/kg of DM), (G3) control ration + OAW (20 mg/kg of DM). Milk production (MP) were unaffected by OAW doses (P&gt;0.05). The supplementation of OAW did not affect the milk composition, and somatic cell count (SCC) (P&gt;0.05). OAW supplementation did not affect blood biochemical values except ketone and glucose. The glucose value increased as the ketone decreased with OAW supplementation (P&lt;0.05). The hematological blood values were not found to be significant. OAW significantly decreased Total oxidant capacity (TOC) and oxidative stress index (OSI) while increasing Total antioxidant capacity (TAC). The current study's findings indicated that OAW can be used as a feed additive to improve cow health and milk production.

A transgenerational study on the effect of granddam conception month on granddaughter test day records for milk production traits in Italian Simmental cattle

The consequences of climate change are becoming a relevant issue also for the livestock industry in temperate countries. Transgenerational studies outlined the effect of the ancestors’ calving season, considered as an indicator of the period during which pregnancy occurs, on their female progeny performance. The aim of this study was to evaluate the effect of great granddam (F0) calving month on their great granddaughters (F3) Test Day (TD) records for milk production. A total of 414,069 TD records of milk, fat, and protein yields from 27,224 Italian Simmental F3 cows was analysed with a mixed linear model with year of calving, parity, age at parity, F0 calving month, days in milk class, the interactions between DIM and F0 calving month and between parity and F0 calving month, F3 calving date and the random effects of herd-test date and animal. The F0 calving month significantly influenced F3 performance for the three considered traits; largest F3 TD records were obtained for F0 calvings occurring in October, smallest for February. The largest milk production of F3 cows were observed when their F1 conceptions occurred in winter. Results were confirmed by a further analysis considering the calving seasons of F0, F1 and F2. The effect of F0 calving month (associated with the conception of F1) on milk production decreased as F3 parity increased. Results of this study suggest that the period of ancestor pregnancy and conception affects milk production traits of further generations also in temperate climates.

Evaluation of the infl uence of inbreeding on milk productivity, reproductive traits and longevity of cows of Holstein breed

The purpose of the work was to evaluate the infl uence of inbreeding on milk productivity, reproductive traits and longevity of cows of Holstein breed. The studies were carried out under the conditions of the breeding farm Konstantinovo. The animals were divided into groups depending on the mating type such as outbreeding and inbreeding. Inbred animals were divided into groups depending on the level of inbreeding: remote, moderate and close. According to the results of the evaluation of the fi rst-calf cows by milk productivity, the highest milk yield, as well as the amount of fat and protein in milk was in cows from moderate inbreeding. It was found that the milk yield for the full and 305 days of lactation of inbred animals (9411 kg and 8408 kg) was higher compared to outbred animals by 1003 kg or 10.6 % and 1028 kg or 13.1 %, respectively. The yield of milk fat and protein in these groups was the highest 346.2 and 308.9 kg. The milk productivity of cows evaluated by the third lactation, the best indicators were in the group of animals with moderate inbreeding as well as in outbred animals. Thus, the milk yield for the full and 305 days of lactation was higher in the group of outbred cows by 876 kg or 9.0 % and 376 kg or 4.6 %. Analysis of reproductive traits of cows showed that live weight at fi rst insemination was higher in the group of inbred animals (373.4 kg), and higher compared to outbred animals by 0.7 %. The age in fi rst insemination in the group of inbred cows was lower by 2.1 months (p &lt; 0.001). It was established according to indicators of longevity and lifetime productivity of cows depending on the level of inbreeding that outbred animals were the best.

Study of the Effects of Alfalfa Bioactive Substances and Polysaccharides on the Lactation Performance and Immune Function of Dairy Cows

Background: The aim of this study was to investigate the effects of alfalfa polysaccharides on the lactation performance and immune function of dairy cows. Methods: A total of 84 healthy Holstein cows were selected and randomly divided into 7 groups, including the control Group A0, the alfalfa polysaccharide groups (AP1, AP2, AP3) and the alfalfa extract groups (AE1, AE2, AE3). Each group had three replicates and each replicate had four cows. The daily rations of the dairy cows in the AP group and the AE group were supplemented with alfalfa polysaccharide powder and alfalfa extract at concentrations of 1, 2 and 3 kg/t, those in the A0 group served as a control. Result: (1) the milk production of dairy cows in the AE groups was extremely significantly greater (p less than 0.01) than that in A0 group and AP groups. The milk protein content of cows in the AP2 and AE2 groups was significantly greater (P less than 0.05) than that in the A0 group (2) The interleukin-2 (IL-2) levels in the serum of cows in the AP2, AP3, AE2 and AE3 groups were greater than those in the A0 and AP1 groups and the IgM antibody levels in the AP group and the AE group were extremely significantly greater than those in the A0 and AP1 groups (P less than 0.01). The IgA antibody level in the serum of dairy cows in the AP2, AP3, AE2 and AE3 groups was significantly (P less than 0.01) greater than that in the A0, AP1 and AE1 groups. In summary, the alfalfa extract improved both the lactation performance and immunity of dairy cows, indicating comprehensive effects. Alfalfa polysaccharides at a concentration of 2 kg/t improved the immunity of dairy cows.

Studying the relationship of the type of higher nervous activity with the milk productivity of cows

The purpose of the presented research was to study the influence of the type of higher nervous activity (HNA) on the secretion of organic components of milk in various milking conditions. The studies were carried out in 2 periods. The first period was standard, and in the second there was a conditioned stimulus - the presence of an outsider. Black-and-white cows were assigned to four types of higher nervous activity: type 1 - strong, balanced; type 2 - strong, unbalanced; 3 - strong, inert; 4 - weak, inhibitory. In the first period, type 2 cows showed a significant decrease in the amount of milk, fat and glucose, but the mass fraction of protein in milk tended to increase separately for each milking by 0.22 %. The ratio of the mass fraction of protein to the percentage of lactose for two milkings was significantly higher by 0.06, in relation to type 1. In type 3, in general, for two milkings, an increase in lactose by 13.3 g, fat - by 7.0 g was noted, in contrast to the indicators of the first type. Animals of the fourth type tended to reduce milk secretion to 18.3 %. Also, the mass fraction of fat in milk was lower to 0.53 % (P &lt; 0.05) and protein to 0.28 %, and the proportion of lactose in milk, on the contrary, was consistently higher in both milkings by 0.25-0,26 % (P &lt; 0.05). In the second period (with a conditioned stimulus), cows of the second group showed a positive trend towards an increase in the mass fraction of protein in the morning with machine milking by 0.26 % (P &lt; 0.05), and with manual milking by 0.32 % (P &lt; 0.05), in relation to the first group. The mass fraction of fat during machine and manual milking in animals of the second type tended to decrease. In the third group, the indicators of milk of the first streams in the morning were higher by 0.99 % (P &lt; 0.05) - fat, by 0.33 % - protein, by 0.09 % - lactose, in relation to the first type of higher nervous activity. In cows with a weak, inhibitory nervous system, the influence of the conditioned stimulus contributed to a decrease in the ratios of the mass fraction of fat and protein in milk to lactose to 0.14 and 0.09, compared with type 1 cows.

Impact of diferent types of selection on the milk productivity of Kostroma breed cows

The article studies the influence of homogeneous and heterogeneous selection on the milk productivity of first-calf cows (milk yield, fat and protein content in milk). The object of research is cattle of the Kostroma breed. The research methods were zootechnical, population-genetic and analytical using computer programs IAS “SELEX” Multifarm and BON-MilkRegion. The modern cattle breeding base in the Kostroma region is represented by three breeding plants and two breeding reproducers. In 2022, the Karavaevo Breeding Farm JSC received 9,297 kg of milk per cow, the Minskoe LLC pedigree reproducer received 7,371 kg of milk, and the Rodina collective farm, Gridino and Agrofirma Planet LLC received more 6000 kg of milk. Record milk yields reach 15,000 kg of milk or more in 305 days of lactation. The following lines have been identified as promising in the Kostroma breed: lines Ladka 2537 and Kursa 3722, related groups Master 106902, Meridian 90927 and Concentrate 106157. To improve the productive qualities of dairy cattle, it is necessary to use both intraline selection and cross-lines, taking into account their compatibility. In breeding farms, using homogeneous selection, high productivity indicators were obtained: in terms of milk yield - from first-calf heifers of the related groups Laird, Concentrate and Meridian, in terms of fat and protein content in milk - Laird and Ladka. With heterogeneous selection, the best combinations were identified across farms.

Effect of Gestational Direct-Fed Microbials Supplementation on the Metabolic Profile in Periparturient Dairy Cows.

This study was conducted at a commercial dairy farm in Queensland, Australia to evaluate the effects of feeding a lactic acid bacteria-based direct-fed microbial (DFM) during gestation on the metabolic profile of periparturient dairy cows and its effects on milk production and body weight. A total of 150 multiparous Holstein cows were randomly selected based on parity (2.3) and days in milk (130 DIM) and divided into two groups of 75 cows each (control and DFM). The control cows were assigned to a basal diet consisting of a silage-based partial mixed ration (PMR), concentrate fed in the dairy twice a day, and ad libitum pasture. The DFM group received the same basal diet supplemented with three strains of Lactobacillus top-dressed in the feed. The DFM supplementation continued during both the dry period and the subsequent lactation. A subset of 82 cows (40 control and 42 DFM) were monitored during the calving season (March to July 2022) to assess the metabolic profile and postpartum performance. Blood samples were collected during the periparturient period (-4 to -2 w prepartum, around calving, and at weeks 1, 3, and 6 postpartum) to measure the levels of metabolites, enzymes, and minerals. Overall, the serum glucose, NEFA, and chloride levels were higher, while protein and urea were lower in cows supplemented with the DFM (p < 0.005). The pre-calving levels of glucose were higher and the total bilirubin, urea, and BHB were lower in cows supplemented with DFM than in the control (p < 0.05). The post-calving levels of glucose and Mg were also higher in the DFM cows than in the control cows (p < 0.05). Average milk production at 110 DIM was significantly higher in the DFM cows compared to control cows (p = 0.03). Although the total milk production over 305 days was numerically greater in the DFM cows, the difference was not statistically significant (p = 0.3), whereas the milk protein percentage was higher in the control cows (p = 0.03). The body weight of the DFM cows was greater during the periparturient period (p = 0.001) than that of the control cows. In the DFM cows, glucose levels had a positive correlation (r = 0.16) with milk yield, at 110 DIM, while serum total protein had a positive correlation with body weight (r = 0.32) (p < 0.05). In conclusion, feeding Lactobacillus-based DFM during gestation can positively influence the metabolic profile of periparturient cows, which, in turn, may affect the milk production and body weight of postpartum dairy cows.

Analysis of the zoonotic tick-borne encephalitis virus (TBEV) in raw milk and dairy products in mountain pastures of the Lombardy region, Italy.

Over the last few decades, tick-borne encephalitis (TBE) has become a growing public health problem in Europe. The tick-borne encephalitis virus (TBEV) is a zoonotic virus that affects the central nervous system (CNS). TBEV has been detected in 27 European countries, and the rise in TBE cases is mainly due to environmental and ecological factors, and factors that increase the risk of human exposure to infected ticks. The infection via the alimentary route is the second most common means of TBEV transmission to humans. Raw milk from infected goats, sheep, or cows has been identified as a source of human food-borne infections. This study aims to gather new information on the prevalence of tick-borne encephalitis virus (TBEV) in raw goat's and cow's milk and related raw products in the Lombard Alps (Italy). This is important due to the close proximity of Lombardy to the Triveneto region, where TBE is endemic, and southern Switzerland, where numerous TBEV-positive mammals have been found. Throughout 2023, a passive monitoring plan was implemented on samples delivered for TBEV analyses from the Alpine pastures. In total, 248 specimens including raw milk, raw milk cheese, and butter were tested. This is the first monitoring of food at risk of TBEV transmission in a non-endemic region with evidence of TBEV circulation. Despite testing a wide range of dairy products, no sample tested positive for RNA-TBEV by real-time RT-PCR. Preliminary results suggest that raw milk and raw dairy products do not pose a significant risk of TBEV transmission to humans in the territory of Lombardy.

Effect of the Temperature-Humidity Index on the Productivity of Dairy Cows and the Correlation between the Temperature-Humidity Index and Rumen Temperature Using a Rumen Sensor.

This study was conducted to evaluate the effects of high-temperature stress on dairy cow productivity and the correlation between rumen sensors. The data were collected on the temperature, humidity, milk productivity, milk components, blood components, and rumen sensor data from 125 dairy cows during the experimental period (1 May 2020 to 30 October 2020). High-temperature stress of dairy cows was evaluated based on the temperature-humidity index (THI). The correlations between the high-temperature stress, productivity, and sensor data were analyzed using SAS and R programs. The THI ranged from 46.9 to 81.0 during the experimental period, and a significant decrease was observed in the milk production of dairy cows during August (p < 0.05). Milk production was evaluated to decrease by 1.8% because of high-temperature stress during the experimental period. There was a significantly high negative correlation between the THI ratio of day and rumen temperature (r = 0.744; p < 0.001). The other rumen sensor data did not show a significant correlation with the productivity of dairy cows. The results can be utilized as a guideline for managing temperature and humidity to maintain dairy cow productivity on farms in high-temperature stress conditions.

A comprehensive analysis of the effects of DGAT1 K232A polymorphism on milk production and fertility traits in Holstein Friesian and Jersey cows reared in Türkiye

Abstract. Research on the diacylglycerol acyltransferase 1 (DGAT1) K232A marker in cattle shows inconsistent results across regions, largely due to small sample sizes, limited genetic variation, and data restricted to few lactations, which complicates establishing a reliable genotype–phenotype correlation. This research aimed to determine the effect of the K232A polymorphism of the bovine DGAT1 gene on milk production and quality traits in dairy cattle. We used 1104 cattle, including 828 Holstein Friesian and 276 Jersey cows. The analysis utilized extensive data from six lactations of cows raised on four commercial dairy farms. We genotyped the population using the polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) technique and Sanger sequencing for verification. We then evaluated the 305 d and test-day milk yields as well as fat and protein yields and percentages. The number of inseminations per conception and calving ease were also assessed as reproduction indices. Genotype–phenotype associations were quantified using linear mixed models. The AA genotype was absent in Jersey cows, and the heterozygous genotype was predominant in both breeds. The K232A marker was significantly associated with test-day milk yield, fat, and protein content in Jersey cows. Further, it substantially affected the fat percentage of milk in Holstein Friesian cows (p&lt;0.001). We found that the KK genotype is highly desirable for milk quality and especially fat content. This comprehensive assessment demonstrated that the KK genotype of the DGAT1 K232A polymorphism significantly influenced fat and protein contents in dairy cattle.

Sensitivity analysis of the INRA 2018 feeding system for ruminants by hybrid local and global approaches: Comparing the contribution of dietary input variables to multiple response prediction in dairy cattle

We conducted sensitivity analysis (SA) of the INRA 2018 feeding system for ruminants applied to dairy cows. We evaluated which dietary input variables contribute most to changes in each output variable, considering the potential interactions presence among input variables. A quantitative analysis (one-at-a-time analysis, OAT; i.e., local SA) and a relative comparative analysis (global SA, GSA) through variance-based SA considering potential interactions and non-monotonicity were applied. The 5 likely influential dietary input variables were selected: CP, Gross energy (GE), OM apparent digestibility (OMd), effective degradability of nitrogen assuming a passage rate of 6%/h (ED6_N) and true intestinal digestibility of nitrogen. The sensitivity of 5 selected animal responses (output variables) to input variables was analyzed: DMI, milk protein yield (MPY), energy in methane (ECH4), nitrogen utilization efficiency (NUE), and ratio between urine and total N excretion (UN/TN). Six diets for dairy cattle, reflecting the diversity of diets commonly used in practice, were formulated to meet 95% of the potential milk production (37.5 kg/d) of a multiparous dairy cow at wk 14 of lactation. For each diet, the 5 input variables were randomly sampled around the INRA 2018 feed table values (reference point), and the animal responses around this reference situation were calculated using the rationing software INRAtion®V5. In OAT, the sensitivity of animal responses was quantified by calculating the normalized tangent value at the reference point, and in GSA, the Sobol indices were calculated for relative influence of each input and their interaction. The influence of the 5 key input variables on the 5 main animal responses predicted from the INRA feeding system was consistent across both SA approaches. With the 6 diets, GE and OMd appeared as the main contributors to changes in DMI, MPY, ECH4, and NUE. Crude protein was the main contributor to changes in UN/TN and another major contributor to changes in NUE. When considering OAT, the sensitivity of outputs showed differences depending on diet, more particularly for DMI and MPY. With grass hay-based diets (GH diets), DMI was less sensitive and MPY was more sensitive to variations in input variables than other diets. When considering GSA, interactions between input variables were also noticeable for DMI and MPY; the interactions were high with the GH diets for DMI, and with fresh ryegrass and grass silage diets for MPY. On the other hand, for MPY, the non-GH diets were less sensitive to variations in input variables and the interaction between inputs was higher than with GH diets. In both cases, the interactions were mainly related to energy-related inputs (i.e., OMd and GE). Our results support the hypothesis that MPY, unlike DMI, is more responsive to energy-related factors at high PDI/UFL ratio (i.e., between metabolizable protein and NEL, e.g., GH diets >117 g PDI/UFL), than at lower PDI/UFL ratio. Hence, hybridizing the SA methods can help to interpret the system and facilitate a more precise evaluation thereof, especially GSA, which is amenable to non-monotonic models such as those characterizing complex feeding systems integrating multiple nutritional and animal factors.

Effect of dietary fat source and concentration on feed intake, enteric methane and milk production in dairy cows

Dietary fat can be used in dairy cow nutrition to reduce enteric methane (CH4), but studies with multiple dietary fat concentrations are scarce. Among fat sources, rapeseed is easily accessible in Europe and North America, and palm kernel fat has been shown to be a potent inhibitor of ruminal methanogenesis. Forty-eight cows (half primiparous and half multiparous) were used in a 6 × 6 Latin square design, with 6 periods of 21 d each. Six treatments were used: a control, 3 fat concentrations (low, medium and high) of rapeseed (RS), and 2 fat concentrations (low and medium) of palm kernel fatty acids (PK). The total crude fat concentrations ranged from 3 to 7% of DM. The cows were fed the treatments as partial mixed ration, and they received additional concentrate from GreenFeed units (1 unit for 12 cows) used to measure CH4 production. Increased dietary crude fat concentration of both RS and PK reduced DMI. The reduction in DMI was stronger in cows fed medium concentration of PK than for any RS concentration, which was comparable to previous studies for both RS and PK. Digestibility of OM was highest at low fat concentration of both fat sources, and lowest at high RS concentration. Digestibility of NDF was reduced by 2 percentage units when cows were fed medium PK concentration instead of the control treatment. Rapeseed supplementation with dietary crude fat up to 5.7% of DM increased milk and energy corrected milk (ECM) yields, but the equivalent PK concentration reduced ECM. Increased fat supplementation decreased CH4 yield (g CH4/kg of DMI) linearly when RS was used, and quadratically when PK was used. Medium PK concentration reduced CH4 yield more than medium RS concentration, but there was no difference for CH4 intensity (g CH4/kg of ECM). Rapeseed fat supplementation with dietary crude fat above 5.7% of DM could reduce further CH4 yield, but fat supplementation was not accompanied by an increase in productivity. The fat source has to be accounted for when considering enteric methane reduction, as the PK provided stronger effect than RS, but the associated reduction in milk production did not support the use of PK for methane reduction.

Effect of Replacing Corn Grain and Soybean Meal with Field Peas at Different Levels on Feed Intake, Milk Production, and Metabolism in Dairy Cows under a Restrictive Grazing.

This study assessed the effects of replacing soybean meal (SBM) and corn grain with field peas in the concentrate of grazing dairy cows on milk production, intake, ruminal fermentation, and blood indicators. Twelve multiparous lactating Holstein-Friesian cows were utilized in a replicated 3 × 3 Latin square design, comprising three periods and three treatments: (1) Pea-0 (Control diet): 6 kg dry matter (DM) of fresh pasture, 7.2 kg DM of grass silage, and 7 kg DM of a concentrate containing 0% pea; (2) Pea-30: Control diet with the concentrate composed of 30% pea; (3) Pea-60: Control diet with the concentrate composed of 60% pea. The effect of treatments on productive and metabolic parameters was evaluated using linear-mixed models. Pasture and total DM intake, milk production, and composition were unaffected by treatments. Despite the concentrates being isonitrogenous and isoenergetic, crude protein (CP) intake was slightly higher in Pea-30 and significantly higher in Pea-60 due to higher pasture CP content in the pasture grazed by these groups, leading to higher milk urea content, though within recommended ranges. Blood parameters showed no significant changes, except for plasma β-hydroxybutyrate, which was lowest in the Pea-60 treatment; however, all values were within ranges not indicative of subclinical ketosis. Ruminal fermentation parameters were similar across treatments. These findings support the use of field peas as a viable alternative to replace SBM and corn grain in concentrates, enabling similar milk production and composition in grazing dairy cows.

Comparative time series analysis of Anatolian water buffalo stock in Türkiye

Water buffalo holds an important place in the livestock heritage in Türkiye. In the current study, buffalo numbers between 2023 and 2032 were estimated by using buffalo number data from 1991 to 2022. In the study, FAOSTAT data between 1961 and 2021 and TÜİK data for 2022 were used to obtain the time series. ARIMA modeling method was used in the study conducted in R programming language. ARIMA is a time series model that can make predictions from time series based on explaining univariate data. According to the results of the analysis made in the study, it is seen that the number of buffaloes in Türkiye will continue to decrease. According to the results obtained, it is estimated that the number of buffaloes will be 157,755 heads in 2023, 96,851 heads in 2027 and 19,136 heads in 2032. The disease resistance of buffaloes, their high adaptability, the high demand for water buffalo products, the preference for high-yielding cows for milk production despite government support payments, increasing mechanization, the reduction of buffalo habitats and the increase in input costs have led to a decline in Anatolian water buffalo populations. To prevent the Anatolian water buffalo from being threatened with extinction, the population decline must be halted and improved. To ensure this, the decline of the pastures that form the buffalo’s habitat must be halted, pasture areas must be increased, and existing pastures rehabilitated, government subsidies for buffalo and calf rearing must be increased and market opportunities for buffalo products must be expanded.