Invited review: Enhancing quality of dairy cattle research through adequate power analysis. By Wang et al., page 8981. Animal research necessitates controlled experiments and statistical hypothesis testing to evaluate treatment effects and answer specific research questions. Given the logistical challenges of sampling entire dairy cow populations, selecting an appropriate group with sufficient sample size is vital for reliable results. Power analysis, which evaluates the probability of detecting true treatment effects, is critical for designing robust experiments.

This study aimed to investigate the associations among early postpartum estrous characteristics (EPEC) and reproductive outcomes in dairy cows fitted with automated monitoring devices (AMD). We hypothesized that EPEC within 41 DIM reflects cows' physiological resilience and serve as predictors of subsequent fertility. Furthermore, we trained and tested algorithms predicting the fertility potential of cows and compared the reproductive performance of cows classified as low, moderate, and high fertility.

The aim of this study was to determine the effect of embryo origin (artificial insemination [AI] vs. in vitro embryo production [IVP]), calf breed, and calf sex on gestation length (GL), birthweight (BiW), calving difficulty (CD) score and perinatal mortality. Lactating dairy cows (n = 1,106) were randomly assigned to be bred by timed AI (frozen-thawed semen) or timed embryo transfer (ET) with fresh or frozen IVP dairy (Holstein Friesian [HF] or Jersey [JE]) or beef breed (Angus, [ANG] or Limousin [LM]) embryos.

Fermented goat milk with kiwifruit (FGMK) and without kiwifruit (FGML) were prepared using 8 isolated lactic acid bacteria strains. Both FGML and FGMK samples showed viable cell counts of 5.70 to 7.14 log cfu/mL and 5.74 to 7.23 log cfu/mL, respectively. After fermentation, milk became brighter and greener. The pH and water-holding capacity results indicated that combining isolated strains and commercial starter cultures gave fermented goat milk good acidification and coagulation properties. Additionally, the incorporation of kiwifruit lowered pH value, increased the titratable acidity, and promoted ketones and esters generation during fermentation.

The aging process is associated with detrimental effects on the integrity of the intestinal barrier, consequently elevating susceptibility to various diseases. Qula exhibits outstanding nutritional composition and has a characteristic taste profile, positioning it as a prime candidate for probiotic exploration given its rich reservoir of probiotic potential. In the present study, a probiotics screening strategy was developed based on the production of short-chain fatty acids (SCFA) to reverse aging-related intestinal barrier dysfunction.

Streptococcus uberis is a common mastitis pathogen that lacks an effective vaccine in the United States and often requires antibiotic therapy. Supplementation of feed with Saccharomyces cerevisiae fermentation products (SCFP) has been associated with decreased SCC in dairy cows. The objective of this randomized clinical trial was to evaluate the effect of oral supplementation with SCFP on clinical and production outcomes in lactating dairy cows in response to intramammary challenge with Streptococcus uberis.

Mongolian horses are famous for their lactation traits. Their milk contains a high protein content and low levels of fatty acids. Given their superior milk composition and historical use in dairy production across Inner Mongolia and Central Asia, Mongolian horses serve as a valuable model for understanding lactational biology. Multiple factors regulate the lactation process; however, a detailed study of this biological process has not been performed with single-nucleus RNA sequencing (snRNA-seq) technology.

To investigate the effects of different heat treatment processes, infusion technology (INF) and UHT, on the physicochemical properties and structural changes of casein and whey protein from bovine milk. Two sterilization conditions, INF (156°C to 158°C, 0.09 s) and UHT (135°C, 4 s) to treat bovine milk and isolate whey protein and casein from milk were selected. This study evaluated the particle size, milk composition, and storage stability of different milk samples, and assessed the structural and property changes of proteins.

Bovine milk (BM) is a common nutrient-rich food, but also a potential allergen for infants with milk allergy. In this study, a method for the preparation of deeply hydrolyzed whey proteins or caseins (DH-WP and DH-CN, respectively) was proposed and residual antigenicity was assessed. The optimal conditions for preparation of DH-WP were hydrolysis with flavorzyme for 5 h at 55°C, pH 6.5, and an enzyme–substrate ratio (E/S) of 10,000 U/g, whereas those for DH-CN were hydrolysis with neutrase for 4 h at 50°C, pH 7, and an E/S of 10,000 U/g.

This study aimed to evaluate sperm morphofunctional characteristics and the ability of spermatozoa to bind to oviduct epithelial cell (OEC) aggregates as predictors of male field fertility. Based on pregnancy per artificial insemination (P/AI) data of 1,833 services in Holstein cows from a commercial dairy herd, sires were classified as of higher (HF, P/AI = 35.0% [362/1,034], n = 3) or lower (LF, P/AI = 21.4% [171/799], n = 4) fertility. Semen quality was assessed based on sperm motility (by computer-assisted sperm analysis, plasma and acrosome membrane integrity, mitochondrial membrane potential, membrane lipid peroxidation, and membrane fluidity [by flow cytometry], and OEC binding).

Heat stress has a myriad of negative effects on dairy production through a disruption in animal homeostasis that often lingers past the exposure. Yet, the effects of heat stress on cellular processes are not fully elucidated. In the present study, we used an electric heat blanket (EHB), pair-feeding heat stress model to investigate the direct effects of heat stress on mitochondrial function and milk production. Multiparous Holstein cows (n = 24, 2.80 ± 0.84 lactations; mean ± SD) were assigned to 1 of 2 treatment groups: EHB-induced heat-stressed (HS) or pair-fed thermoneutral (PFTN) groups.

Listeria monocytogenes is a significant foodborne pathogen capable of surviving various stress conditions encountered during food processing. The aim of this study was to evaluate the influence of osmotic pressure induced by NaCl (4% and 6%) on the phenotypic antibiotic resistance, biofilm-forming capacity, and slime production of L. monocytogenes isolates from food processing environments. A total of 10 isolates of L. monocytogenes were subjected to osmotic stress. Antimicrobial resistance was assessed using the disk diffusion method and MIC, and biofilm and slime production capacities were determined through biofilm production indices (BPI), and culture on stainless-steel 304 and polyurethane coupons and Congo red agar, respectively.

Hispanic-style cheeses (HSC), particularly fresh soft varieties, have been associated with numerous outbreaks of Listeria monocytogenes, highlighting the need to identify product characteristics or interventions that could mitigate L. monocytogenes growth. This study characterized the behavior of L. monocytogenes in commercial HSC, specifically queso fresco (QF) and queso cotija (QC), with the goal of identifying compositional characteristics that could be used as a potential control measure to reduce foodborne illness risks associated with these products.

Bovine chymosin is a protease of commercial interest in the food industry for milk clotting during cheese production. Today, chymosin is mainly produced by recombinant DNA technology in fungi. The methylotrophic yeast Komagataella phaffii (syn. Pichia pastoris) represents one of the best microbial platforms for heterologous protein production in the context of industrial biotechnology. Regulated gene expression in K. phaffii is typically based on the use of the inducible alcohol oxidase I promoter (PAOX1), which relies on the presence of methanol, a toxic and flammable compound.

Dietary microbial additives often benefit production performance in dairy cows. The objectives were to determine the effects of microbial additives on rumen microbial diversity, total-tract digestibility, incorporation of dietary N into milk N, and serum metabolites. One-hundred and 17 cows at 61 d postpartum (31–87 d) were blocked by parity group and pretreatment ECM yield. Within block, cows were randomly assigned to receive 100 g of corn meal containing no microbial additive (CON; n = 40), 100 g of corn meal containing 5 g of a mixture of Clostridium beijerinckii and Pichia kudriavzevii (G1; 4 × 107 cfu of C.

Neonatal dairy calves are highly susceptible to Mycobacterium avium ssp. paratuberculosis (MAP) infection, but data remain limited on early infection prevalence and transmission drivers. This study aimed to estimate the true prevalence of MAP infection and identify associated risk factors in Chilean dairy calves younger than 60 d of age. Fecal and environmental samples were collected from 579 calves across 39 dairy herds. The MAP detection used a phage-based method (PhMS-qPCR) that selectively identifies viable bacteria, and a Bayesian model was used to account for biased diagnostics test results.

An accurate estimation of metabolizable energy (ME) content is critical for optimizing dairy cattle nutrition and improving feed efficiency. This meta-analysis used data from studies conducted in Wageningen (the Netherlands) using Holstein cows and in Nebraska using Jersey cows to refine predictive models of dietary ME content (kJ/kg DM) based on total-tract digestible nutrients. In the Wageningen studies (except for one study), apparent total-tract digestibility of nutrients was estimated using chromium oxide as an external marker included in the concentrate.

The study aimed to investigate the regulatory effects of exopolysaccharides (EPS) derived from Pediococcus acidilactici S1 on the cell physiological functions of Lactobacillus plantarum FQR during the freezing process. Results demonstrated that the addition of 70 mg/mL EPS as a cryoprotectant achieved a maximum survival rate of 91.99 ± 3.52%. The EPS effectively mitigated cell wall and membrane damage, reduced membrane permeability, and stabilized membrane fluidity. Furthermore, EPS decreased the freezing point of the solution from −17.37°C ± 0.19°C to −17.08°C ± 0.20°C, thereby inhibiting ice crystal formation and maintaining post-freeze-drying stability in DNA structure, membrane structure, cell wall protein structure, and unsaturated fatty acid composition within cells.