Search Results (620)

Heat stress is a major management challenge in dairy cows, leading to lower dry matter intake (DMI), reduced milk yield (MY), and changes in milk composition. A practical nutritional strategy is supplementing diets with live yeast (Saccharomyces cerevisiae) during hot periods. This meta-analysis evaluated the effects of live-yeast supplementation on DMI, MY, and milk components in heat-stressed dairy cows. Bibliographic searches for the period 2000 to 2025 were conducted. Based on the inclusion and exclusion criteria, 14 studies were selected. For each outcome, effect sizes were reported as the standardized mean difference (SMD) and the raw mean difference. Analyses were conducted using a random-effects model, and heterogeneity was assessed using the Q test and the I² statistic. Based on the SMD, live-yeast supplementation of the diets of heat-stressed dairy cows increased both DMI (p = 0.003) and MY (p < 0.001). Milk fat percentage (MFP; p = 0.104) and milk lactose percentage (MLP; p = 0.530) were not significantly affected, whereas milk protein percentage (MPP) tended to increase (p = 0.078). In contrast, milk fat yield, milk protein yield (MPY), and milk lactose yield (MLY) all increased significantly (p ≤ 0.001). Heterogeneity was significant only for DMI, MPY, and MLY. Overall, based on the available evidence, supplementing heat-stressed dairy cows with live yeast can improve DMI and MY, and increase milk component yields, without materially altering component percentages. Full article

This study was conducted to investigate the effects of dietary polyunsaturated fatty acid (PUFA) levels and FME (flavor and multiple enzymes) on the reproductive performance, nutrient digestion, and metabolism, immunity, and antioxidant capacity of sows and piglets. Forty primiparous sows [Duroc × (Landrace × York)] were randomly assigned from day 107 of gestation to day 7 post-weaning to one of four dietary treatments, low PUFA (4.6% tallow, LP), high PUFA (4.6% fish oil, HP), and LP and HP, each supplemented with 600 mg/kg FME (LP + FME, HP + FME). Results showed that dietary HP + FME supplementation significantly alleviated sow backfat loss during lactation (p < 0.05). Dietary FME supplementation significantly increased milk lactose and solids-non-fat (p < 0.05) on day 15. Meanwhile, milk protein and true protein contents were significantly lower in the LP treatment than in the LP + FME and HP treatments. The apparent total-tract digestibility (ATTD) of ash and phosphorus was improved (p < 0.05) by both HP diets and FME supplementation. The ATTD of energy and dry matter was significantly higher in LP + FME treatment than in LP and HP + FME treatments (p < 0.05). HP diets increased serum malondialdehyde (MDA, p < 0.01), total superoxide dismutase (p < 0.05) in sows, and increased serum MDA and decreased hydrogen peroxide (H₂O₂) contents in piglets (p < 0.05). Dietary FME supplementation decreased serum H₂O₂ contents and increased serum catalase activity of sows and/or piglets (p < 0.05). The serum immune markers, lipid, and protein metabolites of sows and piglets were altered (p < 0.05 or p < 0.10) by HP diets and/or FME supplementation. In conclusion, dietary fish oil (4.6% of diet replacing tallow) and FME (600 mg/kg) supplementation improved lactating performance by improving nutrient digestibility, body reserve mobilization, antioxidant capacity, and health state of sows and piglets. Full article

The aim of this study was to assess the influence of milk’s rennet coagulation properties (RCPs) on cheese yield and cheese-making losses in the production of Parmigiano Reggiano PDO cheese. Higher contents of citric acid (181.10 vs. 172.13 vs. 166.47 mg/100 g) and phosphorus (95.02 vs. 91.14 vs. 88.78 mg/100 g) in milk with optimal and sub-optimal RCPs, compared to milk with poor RCPs, respectively, positively affect the acidity of the milk, lowering the pH values (6.68 vs. 6.70 vs. 6.72, respectively), which results in a faster reaction between chymosin and casein and consequently a reduced time of milk coagulation. The lower values of curd firming time and the higher values of curd firmness, strength to cut (68.97 vs. 64.43 vs. 44.38 g), and strength to compression (31.48 vs. 30.49 vs. 25.70 g) for milk with optimal and sub-optimal coagulation, compared to milk with poor coagulation, result in a higher stress resistance across the technological steps of the cheese-making process, leading to lower fat losses (14.23 vs. 15.48 vs. 16.72%) in the whey and a higher cheese yield (8.79 vs. 8.56 vs. 8.08 kg/100 kg). Full article

The valorization of cull sheep and the incorporation of agro-industrial by-products into animal feeding represent effective approaches to enhancing the sustainability of small ruminant production systems. This study investigated the effects of dietary inclusion of 17% partially destoned olive cake (OC) in the concentrate fed to Valle del Belice ewes on carcass characteristics, as well as on meat and salami quality. A 14-week feeding trial was conducted on 124 animals allocated to a control (CTR) and an experimental (EXP) group, balanced for parity, days in milk, and daily milk yield. At the end of the trial, five animals per group were slaughtered and their meat was processed into three types of salami: 100% sheep meat (SM), 90% sheep meat with 10% beef heifer brisket (HB), and 90% sheep meat with 10% pork backfat (PB). Meat and salami were evaluated for chemical composition, fatty acid profile, polyphenol content, antioxidant capacity, lipid oxidation, microbiological status, textural properties, and sensory characteristics. Dietary OC supplementation resulted in increased carcass weight, separable fat, intramuscular fat content, and monounsaturated fatty acids—particularly oleic acid—along with higher polyphenol levels and antioxidant activity. Salami produced from OC-fed ewes exhibited reduced weight loss during ripening, lower lipid oxidation, an improved MUFA/SFA ratio, and satisfactory sensory attributes. Microbiological analyses indicated a dominance of lactic acid bacteria and coagulase-negative staphylococci, with no pathogenic microorganisms detected. Overall, the inclusion of olive cake in the diet enhanced meat and processed product quality, supporting the valorization of olive oil by-products within circular economy frameworks. Full article

Background/Objectives: Staphylococcus aureus is a multifaceted pathogen responsible for diseases in humans and in several animal species, including dairy cows. This study aimed to characterize and compare the genetic diversity, lineage distribution, and antimicrobial resistance profiles of S. aureus isolates from bovine milk with human-derived reference genomes to investigate host adaptation and inter-species transmission. Methods: Genomic analyses were performed on S. aureus isolates from quarter milk samples of dairy cows together with human-derived sequences from public databases. Whole-genome sequencing and multi-locus sequence typing (MLST) were used to determine sequence type (ST) distribution, and the presence of key antibiotic resistance genes and mobile genetic elements (MGEs) was assessed. Comparative genomics was applied to evaluate gene content, phylogenetic relationships, and lineage–host associations. Results: The dataset encompassed bovine-adapted lineages (CC97, CC133, CC151) and human-associated lineages (CC1, CC5, CC8, CC30, CC45), as well as livestock-associated ST398 in bovine samples and human-adapted ST5 and ST6 in animals. ST8 was the only ST shared between animal and human isolates and showed differing resistance profiles, with animal ST8 carrying resistance determinants absent from human ST8. Bovine-adapted strains were characterized by recurrent loss of human-associated virulence genes and acquisition of bovine-associated mobile genetic elements, and blaZ and mecA were rarely detected in bovine-adapted CC97 but were frequently present in human CC5 and CC8. Overall, animal isolates carried fewer resistance genes than human isolates. Conclusions: S. aureus from dairy cows and humans displayed substantial genetic diversity, with evidence of host-associated lineages and dynamic changes in gene and mobile element content. These findings support the need for integrated One Health surveillance to track shared and host-adapted lineages and their antibiotic resistance determinants. Full article

Reticuloendotheliosis virus (REV) is an immunosuppressive virus in poultry that can cause acute reticular neoplasms, chronic lymphoid tumors, stunting syndrome, and secondary infections. In many countries, the lack of effective vaccines has resulted in a high prevalence of REV infections and substantial economic losses. Enzyme-linked immunosorbent assay (ELISA)-based antibody detection is an important tool for monitoring the REV prevalence in poultry farms. ELISA coating antigens generally consist of either whole virus or viral protein; however, most commercially available REV antibody ELISA detection kits use whole virus as the coating antigen, which limits their applicability in certain diagnostic and research settings. In this study, the gp90 protein from a dominant REV strain was expressed and purified using 293F suspension cell eukaryotic expression system. Using recombinant gp90 protein as the coating antigen, an indirect ELISA for detecting gp90 antibodies (gp90-ELISA) was developed. After optimization, the optimal conditions were as follows: coating antigen concentration of 4 µg/mL with overnight incubation at 4 °C; blocking with 5% skim milk at 37 °C for 1.5 h; serum dilution of 1:200 with incubation at 37 °C for 45 min; secondary antibody dilution of 1:1000 with incubation at 37 °C for 30 min; and color development using TMB substrate at room temperature in the dark for 10 min. The cut-off value was defined as an OD₄₅₀ ≥ 0.22 for positive samples and <0.22 for negative samples. The developed gp90-ELISA specifically detected REV-positive sera at a maximum serum dilution ratio of 1:3200. Intra- and inter-assay variation coefficients were ≤10%, indicating that the gp90-ELISA had good specificity, sensitivity, and reproducibility. Laboratory serum testing showed that the gp90-ELISA successfully detected sera from chickens immunized with the gp90 protein or infected with REV. Furthermore, analysis of clinical serum samples demonstrated 100% concordance between the gp90-ELISA results and a commercial whole-virus-coated ELISA kit. These results indicate that the gp90-ELISA is a reliable supplementary method to whole-virus-coated ELISA and has potential utility in disease surveillance and evaluation of immune responses. Full article

Background: Postnatal growth failure in very preterm infants remains a major concern in neonatal care and clinical management is complicated by the lack of a standardized definition. This study aims to identify risk factors for growth faltering (GF) and undernutrition (UN) at hospital discharge, defined according to the latest consensus definitions established by the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN). Methods: We conducted a retrospective observational study of 416 preterm infants (gestational age < 32 weeks and/or birth weight < 1500 g). Growth was monitored using the Intergrowth 21st standards. In line with ESPGHAN criteria, GF was defined longitudinally as a weight for age (WFA) z-score decline ≥ 1 SD from birth, while UN was defined cross-sectionally as a WFA or length for age z-score < −2 SD at discharge. Logistic regression models were used to determine independent predictors for both growth phenotypes. Results: At discharge, the prevalence of GF and UN was 45.3% and 33.1%, respectively. In infants born without growth restriction (GR), UN was almost entirely driven by GF (89.7%). In contrast, 85.5% of infants born with GR remained undernourished at discharge. Multivariate analysis identified bronchopulmonary dysplasia and higher maximal postnatal weight loss as major independent risk factors for GF, while female sex and human milk feeding at discharge were associated with a lower risk of GF. For infants born with adequate weight, maternal hypertension, extremely low birth weight, and the co-occurrence of GF were the strongest predictors of UN. Conclusions: Nearly half of very preterm infants experience significant growth impairment before discharge. By assessing the dynamic process of GF and the static endpoint of UN, we identified distinct clinical trajectories. Standardized ESPGHAN criteria allow for the identification of high-risk “phenotypes”—particularly those with GR at birth or severe neonatal morbidity—enabling more targeted and intensive nutritional management during the critical developmental window. Full article

The effects of pelleting a total mixed ration (TMR) for dairy sheep were investigated in an experiment involving 24 lactating Assaf ewes, which were assigned to two groups and fed the same TMR ad libitum, offered either in pelleted (PTMR group, n = 12) or in unpelleted form (CTMR group, n = 12). The experiment lasted 28 days, during which feed intake, eating behavior (including meal frequency and size, meal duration, eating rate, between-meal interval), and milk yield were recorded daily. Body weight (BW) was recorded on days 1 and 28 and milk samples were collected on days 1, 8, 15, 22 and 28 for milk composition analysis. Blood acid-base status was determined at the beginning and at the end of the trial. Ewes fed the CTMR diet exhibited (p < 0.05) a higher meal frequency and longer meal duration, along with a smaller meal size and slower eating rate. However, feed intake in this group was less than that in ewes fed PTMR only during the final two weeks of the experimental period. Total eating time was also longer (p < 0.001) in the CTMR group, whereas the average time between meals was shorter (p < 0.002). No differences (p > 0.05) were observed between dietary treatments in blood acid-base status, milk yield or milk composition. However, a diet x day interaction (p < 0.05) was detected for milk yield, as during the last 2 weeks of the experimental period the ewes fed the PTMR yielded more milk than those fed the CTMR. Feed conversion ratio did not differ between groups (p > 0.05), but body weight loss was greater in ewes fed the CTMR diet (−3.00 vs. −0.58 kg; p < 0.05). A trend toward improved feed efficiency was observed in the PTMR group when calculated based on milk yield corrected for that theoretically derived from the mobilization of body reserves (1.98 vs. 1.41 g DMI/kg milk; p = 0.077), with estimated contributions from body reserves of 485 g/day in the CTMR group and 70 g/day in the PTMR group. In conclusion, the use of pelleted total mixed rations in high-yielding dairy ewes enhances feed intake, feed efficiency, milk yield, and energy balance without adversely affecting milk composition or animal health in the short term. Full article

This study was conducted to evaluate the effect of rumen-protected γ-aminobutyric acid (GABA) supplementation on milk productivity of lactating Holstein cows. Eighteen Holstein dairy cows (mean parity, 2.2 ± 1.0 year; mean milk yield, 34.3 ± 5.5 kg) were selected in a commercial dairy farm for the experiment. The experiment was conducted from 17 July 2024 to 11 September 2024 (56 days). Generally, THI 72 is set as a threshold since the productivity of Holstein cows starts to decrease. Animals were exposed to heat stress conditions (THI ≥ 72) during the experimental period. The basal diet was fed as a total mixed ration (TMR), and GABA was top-dressed onto the TMR. The treatments were basal diet (Control), basal diet supplemented with rumen-protected GABA 3 g/d (Treatment 1), and basal diet supplemented with rumen-protected GABA 6 g/d (Treatment 2) as a completely randomized design. Statistical significance was compared between the control and GABA treatment groups using the method of repeated measurement. Increased levels of rumen-protected GABA supplementation tended to mitigate the decline in milk yield associated with heat stress (p = 0.083). Milk fat content in the GABA supplementation groups was significantly greater than that in the control group (p = 0.036). Milk lactose content was significantly increased by GABA supplementation (p = 0.017). Blood metabolic profiles and cortisol did not differ significantly between the control and GABA supplementation groups. Activities in the GABA supplementation groups were significantly greater than those in the control group (p < 0.05). Rest and rumination times in the GABA supplementation group were significantly lower than those in the control group (p < 0.05). These results suggest that rumen-protected GABA can be a practical nutritional intervention for minimizing productivity losses in Holstein cows during periods of elevated ambient temperature. Full article

Phosphorus (P) is a key macromineral essential for numerous physiological processes, including energy metabolism, skeletal mineralization, and cellular signaling. In dairy cattle, its homeostasis is tightly regulated by parathyroid hormone, calcitriol, and fibroblast growth factor 23 (FGF23). Phosphorus deficiency is common during the transition period and is associated with reduced milk yield, anemia, muscle weakness, and immunosuppression in severe or prolonged cases. This review summarizes the current understanding of phosphorus metabolism in ruminants, emphasizing differences from monogastric species, hormonal regulation, and the clinical manifestations of deficiency. Particular attention is given to postpartum hypophosphatemia, its relationship with acute-phase proteins, and the pathogenesis of postpartum hemoglobinuria and recumbency. The review also discusses diagnostic methods for assessing phosphorus status, recent findings on FGF23 physiology in cattle, and including demonstrated effects of phosphorus imbalance on periparturient immune suppression and increased environmental phosphorus losses through manure. Maintaining optimal phosphorus nutrition is crucial for bovine health, productivity, and reduction in environmental phosphorus losses. Full article

This study investigated how corn processing and protein degradability affect ruminal fermentation and feeding behavior in lactating Holstein cows. Twenty cows (averaging 162 ± 70 days in lactation, 666 ± 7 kg body weight, and 36.0 ± 7.8 kg/day milk yield) were assigned in a Latin square design with four 21-day periods and four treatments arranged in a 2 × 2 factorial: corn processing [ground corn (GC) vs. steam-flaked corn (SFC)] and crude protein (CP) degradability [high (HCP) vs. low (LCP)]. Ruminal samples were collected at eight time points (0, 2, 4, 6, 8, 10, 12 and 16 h) post-feeding to analyze pH, ammonia, and short-chain fatty acids, while feeding behavior was recorded visually every 5 min for 48 h. Corn processing and protein degradability interacted to influence rumen ammonia nitrogen (p = 0.057), urinary pH, (p = 0.041), nitrogen secretion and efficiency (p = 0.538), and feeding (min/kg DM; p = 0.049) and rumination times (min/kg DM, p = 0.001; min/kg NDF, p = 0.001), reflecting changes in nitrogen metabolism. Steam-flaked corn decreased the acetate/propionate ratio and enhanced propionate production, improving nitrogen retention and reducing urinary N losses, while highly degradable protein increased ruminal NH₃-N and branched-chain VFA concentrations, particularly when combined with ground corn. Additionally, steam flaking reduced feed selectivity and increased rumination efficiency, supporting more effective use of nutrients for milk N secretion and overall nitrogen utilization efficiency in dairy cows. Overall, diets varying in corn processing and protein degradability altered ruminal metabolism, nutrient utilization, feeding behavior, and diet selectivity in lactating cows, highlighting their importance in optimizing dairy cow performance. Full article

This study evaluates the impact of high ambient temperature (HT) on milk production in Tunisian local goats using both fixed and random regression models with quadratic and cubic Legendre polynomials. Daily minimum (Tmin), maximum (Tmax), and average (Tavg) temperatures were tested as heat load indicators, measured on the milking day and averaged over the 1–3 preceding days. The deviance information criterion (DIC) consistently showed that models including temperature effects provided a better fit than a baseline model without heat load. Cubic polynomials showed superior accuracy compared with quadratic models, even if the differences were relatively small. The best model was obtained with Tavg on the milking day, followed closely by Tmax averaged across one or two preceding days. The population response showed a thermoneutral plateau at lower temperatures, followed by declines beyond the HT thresholds. For Tmax, moderate and severe thresholds were detected at 20–23 °C and 25–27 °C, respectively, while for Tavg, thresholds occurred at 11–13 °C and 16–19 °C. Milk losses ranged from 22 to 85 g/°C depending on the temperature indicator, representing an average 4–5% decline in daily yield per degree above thermoneutrality. High variability in individual responses was observed. Some goats maintained stable production, while others showed steep declines under HT, with slope differences reaching over 150 g/°C. Correlations of milk yield across contrasting thermal environments were low, indicating that animal ranking changes with temperature. High-producing goats are more affected by heat, showing the need for a balance between production and heat tolerance. Full article

Subclinical mastitis is a major but often overlooked constraint to dairy productivity, causing economic losses through reduced milk yield and quality. In Romania, comprehensive data on the bacterial etiology and antimicrobial resistance (AMR) of subclinical mastitis are limited. This study aimed to characterize the etiological agents and antimicrobial susceptibility profiles of major bacterial pathogens isolated from subclinical mastitis cases in dairy cows from Western Romania. Between 2021 and 2022, milk samples were collected from 117 lactating cows diagnosed with subclinical mastitis on three dairy farms. Bacterial isolation and differentiation were performed on ChromID^® CPS^® Elite Agar, and isolates were confirmed by standard biochemical tests. Antimicrobial susceptibility testing of Staphylococcus aureus and Escherichia coli isolates was conducted using the automated Vitek^®2 system, interpreted according to CLSI veterinary standards. Multidrug resistance (MDR) was defined as resistance to at least one agent in three or more antimicrobial classes. Bacterial growth occurred in 51 of 117 samples (43.6%). S. aureus subsp. aureus predominated (28.2%), followed by E. coli (4.3%), Klebsiella pneumoniae subsp. pneumoniae (2.3%), and Streptococcus uberis (2.3%). Mixed infections occurred in 6.0% of positive samples. Among S. aureus, the highest resistance rates were to fosfomycin (58.3%), penicillin (44.4%), clindamycin (44.4%), and tetracycline (41.7%), with 47.2% MDR isolates. E. coli showed resistance to amoxicillin/clavulanic acid (88.9%), ampicillin (55.6%), and cefotaxime (55.6%), with 66.6% MDR. S. aureus remains the leading cause of subclinical mastitis in Western Romania. The high MDR rates highlight the need for targeted antimicrobial stewardship, culture-based therapy, and continuous AMR monitoring under the “One Health” framework. Full article

Background/Objectives: After perinatal loss, namely stillbirth and neonatal death, many bereaved mothers continue to produce breast milk, facing the decision as to whether to suppress lactation or donate their milk. Our aims were to explore the experiences and views of Muslim mothers who had donated their breast milk following perinatal loss and examine the Islamic legal-ethical perspectives relating to milk donation. This research explores how milk donation serves as a coping mechanism and how Islamic teachings frame its permissibility and ethical considerations. Methods: A qualitative research methodology was employed, using a Interpretative Phenomenological Analysis (IPA). Nine bereaved Muslim mothers who had donated their breast milk and three Islamic religious scholars (an Imam, a Mufti, and a Muslim jurist) participated in in-depth interviews. Thematic analysis identified recurring patterns and insights. Results: Our findings revealed that mothers experienced milk donation as a coping mechanism, allowing them to maintain a symbolic connection with their lost child while contributing to other infants’ survival. Religious scholars who we interviewed agreed that milk donation is permissible in Islam, provided that milk kinship (rida’a) regulations are observed. Mothers reported a strong need for structured support from healthcare providers and religious leaders in order to assist in the informed decision-making process. Conclusions: Breast milk donation after perinatal loss aids in grief management for bereaved mothers while benefiting vulnerable infants. Healthcare providers should offer comprehensive lactation counseling for bereaved mothers, including milk donation options. Milk banks should implement processes in alignment with rida’a guidelines. Improving support systems for bereaved mothers can alleviate their grieving process while ensuring alignment with cultural and religious norms. Full article

Dual-purpose livestock farming in the Colombian low tropics faces nutritional limitations that affect productivity and increase enteric methane (CH₄) emissions. Therefore, it is necessary to evaluate supplementation strategies that optimize the use of nutrients and reduce environmental impacts. The objective of this study was to evaluate the effects of three types of dietary supplementation—mineralized salt (MS), proteinized salt (PS), and concentrated feed (CO)—on milk production, efficiency in the deposition of dairy nutrients, and enteric CH₄ emissions in dual-purpose grazing cows in the Colombian Amazon. Twenty-four F1 Holstein × Gyr cows were used in a completely randomized block design. Nutrient intake, digestibility, composition, and efficiency in the milk deposition of Ca, P, K, and N were measured; additionally, CH₄ emissions were assessed using a portable electronic spirometry mask. The results indicated that the treatments did not modify the total intake of dry matter or the production and composition of milk. CO and MS supplementation improved the efficiency of Ca and P (p < 0.03) deposition in milk, while no differences were observed for N and K. CH₄ emissions (196 ± 17.9 g/cow/day) were not affected by the supplements and were within the ranges reported for dual-purpose tropical systems. However, with the supplementation with CO was a lower losses of gross energy intake as CH₄ (Y_m) (p < 0.05). In conclusion, supplementation with the evaluated products did not impact milk production or CH₄ emissions, although with CO was lower energy losses as CH₄ and, CO and MS improved the use of Ca and P, which highlights the importance of adjusting supplementation to optimize nutritional efficiency without increasing greenhouse gas emissions. Full article