Journal of Dairy Science最新文献

Dairy cows are highly motivated to use grooming brushes, and their use promotes expression of natural behavior. Although brushes are increasingly common on commercial dairy farms, little is known about how their mechanical properties, specifically swingability and rotation, influence cattle preferences for brush use. This study investigated adult dairy cow preferences for 3 brushes identical in physical and visual features but differing mechanically: (1) swinging and rotating, (2) swinging-only, and (3) stationary (neither swinging nor rotating). We predicted cows would prefer swinging brushes for their ability to reach multiple body regions and that rotation would further enhance engagement. Fourteen primiparous Holstein cows were habituated and individually exposed to all 3 brushes before testing. Over 9 d, each cow had simultaneous access to all brushes during 5-min sessions in a test arena. Brush interactions were video recorded and analyzed for first-choice preference, grooming duration, and body region contacted (head, neck, back, or rump); generalized linear mixed models accounted for zero inflation and repeated measures (back-transformed values with 95% CI). There was individual variation in brush preference; 10 of the 14 cows preferred the swinging-rotating brush, 3 preferred the swinging-only brush, and one preferred the stationary brush, based on total brush use duration. First-choice rates did not differ between swingintg-rotating and swinging-only brushes, but both were greater than first-choice rates for the stationary brush or no brush choice. Grooming time varied by brush type and body part. Cows used all brushes to groom the head for similar durations (approximately 113, 103, and 122 s for swinging-rotating, swinging-only, and stationary brushes, respectively), but the stationary brush was used almost exclusively for the head. Cows used the swinging-rotating and swinging-only brushes for similar durations to groom other body parts. To groom the neck, cows used the swinging-rotating brush more than the stationary brush (approximately 95 and 13 s, respectively), but not more than the swinging-only brush (approximately 59 s). To groom the back and rump areas, cows used the swinging-rotating brush (approximately 92 and 144 s, respectively) and swinging-only brush (approximately 31 and 81 s, respectively) more than the stationary brush (approximately 1 and 9 s, respectively). Overall, cows favored brushes that could swing, likely because this feature enabled grooming of multiple body regions. However, the stationary brush may offer more tactile precision for head grooming. Brush design, particularly swingability, strongly influences cow grooming behavior. Future research should explore how providing brush variety affects welfare and investigate the underlying motivations for individual preferences.

In dairy systems, β-LG, the predominant whey protein, is valued for its nutritional and techno-functional properties, yet it remains a major milk allergen. Modulating protein-ligand interactions presents a potential strategy to alter its characteristics. Although interactions between β-LG and polyphenols have been extensively studied, the binding mechanisms with other common food-grade molecules possessing diverse structural features remain less understood. Therefore, this study selected 3 such additives representing distinct chemical categories: galactooligosaccharides, sucrose fatty acid esters, and casein phosphopeptides, to explore how their unique functional group profiles (hydroxyl, amphiphilic, and phosphopeptide moieties, respectively) drive their interaction with β-LG. We employed a combined multispectroscopic and computational approach to build a qualitative, mechanistic portrait of these interactions. Our findings demonstrate that all 3 additives interact with β-LG, primarily via a static fluorescence quenching mechanism, which alters the protein's local microenvironment without significantly perturbing its secondary structure. These experimental observations are complemented by an in-depth computational analysis, including molecular docking, extensive molecular dynamics simulations, and binding free energy calculations. This integrated approach not only identified the specific binding modes and key interacting residues, but also quantitatively highlighted the crucial roles of hydrogen bonding and hydrophobic forces in stabilizing the complexes. Collectively, this work provides a theoretical basis for future efforts to modulate whey protein functionality and explore its potential impact on milk allergenicity.

Digital technologies and the internet determine our professional and private everyday life. This also applies to the dairy industry and veterinary practice. The objective of the presented study was to learn more about the perception of digital technologies by students of veterinary medicine (VetMed) and agricultural sciences (AgriSci) in Germany, Austria, and Switzerland. This next generation of farmers and veterinarians will have to deal with digital technologies in their later professional lives and they will have to face societal demands such as animal welfare and the reduced use of pharmaceuticals. We created an online survey comprising 6 sections: (1) demographic data, (2) questions about the participants' relationship to today's dairy industry, (3) participants' perception of digital technologies in everyday life and in the dairy industry, (4) associations based on the effects of images, (5) visions and expectations of the dairy industry in the future. Finally, the participants were asked whether they felt well prepared for the digital transformation in the dairy industry by their colleges. The survey link was sent to the students through their administration or student body of veterinary medicine and agricultural sciences colleges and faculties in Austria, Germany, and Switzerland. In total, 454 questionnaires were eligible for the final analysis, 318 from veterinary medicine students, and 136 from agricultural science students. In general students of both disciplines have a positive attitude toward the use of digital technologies as all participants of the study showed a high acceptance of cows being equipped with sensors. But the survey shows also areas in which the students are skeptical about the technological progress and especially VetMed students did not agree with some procedures in dairy cattle husbandry such as early cow-calf separation and an automatic feeding of calves. They also associated digital technologies with a reduction or even a loss of human-animal relationship. One reason for this can be seen in the preparation for the digital transformation in the dairy industry. Almost 50% of VetMed students were not "adequately prepared" for this transformation during their studies; among AgriSci students, it was one-third of the respondents. The current survey provides a fundament for discussing various topics against the background of digitalization in the dairy industry. Representative examples are veterinary education and the shortage of livestock veterinarians.

Due to its superior antioxidant and anti-inflammatory properties, milk thistle has been widely used in various applications. In the present study, the effects of milk thistle seeds (MTS) powder and its ethanolic bioactive compounds extract on fermented goat milk were investigated. Fresh goat milk was enriched with 0.5%, 1%, and 2% of MTS powder and its extract, and the obtained product was analyzed after 1 and 14 d of cold storage. The MTS bioactive compound-ethanolic extract displayed higher antioxidant activities (DPPH•, ABTS•⁺, and ferric reducing antioxidant power) and total phenolic compounds compared with those extracted by using homogenization, ultrasonication, or microwave. The fatty acid composition analysis of MTS oil revealed that linoleic, oleic, palmitic, and stearic were the predominant fatty acids. The results also show that the addition of MTS significantly affected different yogurt characteristics. The MTS extract-enriched samples had higher moisture content than MTS powder-enriched and the control samples. Yogurt color, texture, and volatile compounds profile were also influenced by the inclusion of MTS into yogurt formulation. The control yogurt samples displayed higher levels of 2,3-butanedione, 2-heptanone, 3-hydroxy-2-butanone, and 2-nonanone. In addition, MTS enhanced the antioxidant activities and microbial quality of goat milk yogurt.

Goat milk is valued for its rich nutritional composition; however, its distinct "goaty" flavor and limited oxidative stability restrict broader consumer acceptance. This study systematically compared thermal (65°C/30 min; 75°C/15 s) and ultrasonic (400-600 W/10 min) treatments on goat milk's lipidome and volatilome via integrated lipidomics and flavoromics. Headspace GC on mobility spectrometry revealed that ultrasound at 500 W boosted the abundance of aldehydes and esters, mitigating thermal degradation. Lipidomics showed the modulation of 213 species, upregulating functional lipids such as linolenic acid (18:3), PUFA, and diacylglycerols, while downregulating sphingolipids-contrasting thermal oxidation. These findings demonstrate ultrasound's enhancement of flavor and functional lipids of goat milk through metabolic modulation, providing mechanistic insights for its application in high-quality dairy.

Enteric methane emissions can be measured on male and female cattle, unlike traditional dairy production phenotypes where a sire's breeding value is estimated from the performance of his female relatives. It is, however, important to validate that young dairy sires are a good model for female dairy animals, by confirming that phenotypic differences in CH₄ emissions in bulls are observed in their daughters. Methane emissions and DMI were measured in a population of young dairy bulls (n = 486) in an indoor feeding trial for 5 wk. An estimated CH₄ breeding value (metEBV) of CH₄ production adjusted for the genetic variance of DMI was created and used to select 25 high metEBV and 25 low metEBV bulls to sire a cohort of heifers. The mean metEBV of the high and low sire groups, respectively, were 1.3 and -1.4 g CH₄/kg DM. There was a phenotypic difference in CH₄ yield of ∼8 g CH₄/kg DM; although the sire groups had a similar DMI, the low metEBV sire group had lower daily CH₄ production than the high metEBV sire group. A population of 393 daughters of high and low metEBV sires were subsequently measured for DMI and CH₄ production in an indoor feeding trial for 5 wk in 1 of 4 lots between 9 and 15 mo of age. The nonlactating heifers from low metEBV sires produced less methane per day, with a similar DMI compared with the nonlactating heifers from high metEBV sires. Furthermore, the daughters of low metEBV sires had a lower CH₄ yield (∼0.8 g CH₄/kg DM per day) compared with the daughters of high metEBV sires. This dataset provided further opportunity to explore phenotypic relationships between CH₄, CO₂, and DMI to scope proxies for future phenotype collection. Carbon dioxide production was investigated as a proxy measure for DMI, and the ratio of CH₄ to CO₂ was also calculated as a trait to be investigated as a proxy for CH₄ yield. A strong phenotypic correlation between CO₂ and DMI, and the CH₄ yield and CH₄: CO₂ ratio was identified for both sires and daughters, which requires further investigation in a larger dataset, but suggests these could be suitable proxies. Further research is required to measure the CH₄ emissions of these daughters during their first lactation, to confirm the phenotypic differences between the daughters of high and low metEBV are observed during lactation.

The focus of study was to investigate physicochemical, microbiological, and quality characteristics of raw standardized milk collected from different northern parts of India. Results showed that physicochemical test values for pH, acidity, moisture, fat, SNF, total soluble solids, protein were varied from 6.62 to 6.66, 0.133% to 0.121%, 84.17% to 86.01%, 5.09% to 6.59%, 8.47% to 9.23%, 13.56% to 15.82%, 36.45% to 36.78%, and 0.61% to 0.73%, respectively. These results were in accordance with Codex International Standard and the Food Safety and Standards Authority of India. The Reichert-Meissl value, Butyro-refractometer reading, and sodium content of raw standardized milk varied from 28.76 to 29.36, 41.31 to 41.63, and 432 to 597, respectively. Various adulterants tests were performed for different milk samples; negative results were obtained for all but 2 samples, which had adulterants such as sugar, skim milk, and antibiotic residues. The results of melamine and aflatoxin M₁ of standardized milk varied between 58.17 and 90.83 and 0.17 and 1.26, respectively. Microbiological analysis showed that in 6 samples of standardized milk, the aerobic plate count and SCC were found to be crossed the upper limit (i.e., 10 × 10⁵ and 25 × 10⁴, respectively). Two samples of standardized milk contained higher MA, TS, and psychotropic count as compared with world standards. The sensory scores for all but 3 standardized milk samples varied from 6 to 8. This study helps to analyze the quality of milk, which is being tainted with various adulterants because of a lack of supervision, unsanitary facilities, or for financial gain.

The objective of this study was to assess the potential benefit of a single-step GBLUP (ssGBLUP) genomic prediction approach to subclinical mastitis (SCM) and SCS traits in the early first lactation of heifers. Subclinical mastitis is highly prevalent during early lactation and poses significant challenges to both animal welfare and farm profitability. Given the low h² of SCM, ssGBLUP has emerged as an effective approach for the genomic prediction of such low-h² traits. This approach combines phenotypic data and genomic and pedigree information simultaneously through a hybrid relationship matrix to predict GEBV. In this study, accuracy and bias of GEBV for SCM (defined in 6 alternative ways) and SCS were assessed using the ssGBLUP approach in Canadian Holstein heifers early in their first lactation. A reference dataset, consisting of a large random sample of 544,221 heifers from 3,021 herds, containing records up to 2021, was truncated to create another dataset with records up to 2016, which were used for breeding value estimation and validation, while a smaller random sample of 137,518 heifers from 755 herds was used for genetic parameter estimation. Validation reliability and prediction bias of GEBV were estimated using ssGBLUP and were compared with the EBV derived from traditional BLUP. For constructing the hybrid relationship matrix used in the ssGBLUP, various scaling factors were tested for combining genomic and pedigree relationships. The incidence of 6 SCM trait definitions within 5 to 30 DIM ranged from 15.32% to 24.71%. Heritability was 0.047 to 0.069 for 6 SCM traits and 0.102 for SCS. Application of the ssGBLUP model substantially increased validation reliabilities of GEBV of young animals, with average gains of 0.28 (SCM traits) and 0.19 (SCS) points with optimal scaling factors. Furthermore, in comparison to EBVs obtained with a traditional BLUP method, the ssGBLUP model had slightly reduced bias in GEBV (overall with various scaling factors). Moreover, in terms of average theoretical reliabilities, gains of 0.22 and 0.27 and 0.20 and 0.28 were observed, respectively, for reference and truncated datasets of SCM traits and SCS, respectively. We concluded that ssGBLUP produced GEBV with increased reliability and less bias for young animals compared with EBV from a conventional BLUP approach. Hence, implementation of ssGBLUP in routine evaluation of SCM should be further considered within the context of the Canadian dairy industry.