Early detection and prompt treatment of lame cows are crucial for proactive lameness management. This study aimed to evaluate a fully automated 2-dimensional imaging system for real-time lameness detection using artificial intelligence. Data were collected from 11 dairy farms in the UK Four trained veterinarians performed 42 mobility scoring sessions using a 0–3 4-grade scoring system, with scores 2 and 3 representing lameness. On each session, individual weekly average scores were calculated. This resulted in 40,116 paired human mobility scores (HMS) and weekly average mobility scores generated using artificial intelligence (AIMS) matched to a cow ID.

The aim of this cross-sectional observational study was to assess whether nulliparous Holstein heifer fertility is associated with (1) energy reserve-related traits, such as body condition score (BCS) and body weight (BW); (2) ovarian reserve-related traits, such as Anti-Müllerian hormone (AMH) and antral follicle count (AFC); and (3) development-related traits, such as anogenital distance (AGD) and vulval length (VUL). From August 2022 through July 2023, we used a prospective approach in which the phenotypic traits (BCS, AMH, AFC, AGD, BW, and VUL) of 698 Holstein heifers were measured once at approximately 12 mo of age (at the beginning of the breeding program).

Niacin, a key component of pyridine nucleotides, plays a vital role in over 200 metabolic reactions, including carbohydrate, lipid, and AA metabolism. This meta-analysis aimed to evaluate the effects of niacin supplementation on lactational performance in dairy cows. We hypothesized that niacin supplementation during the transition or lactating periods would enhance the productive performance of dairy cows. A systematic review identified 41 experiments, comprising 128 treatment means and 1,992 cows, which were included in the meta-analysis.

High nonesterified fatty acid (NEFA) concentrations in cows with clinical ketosis lead to metabolic dysfunction in mammary cells, resulting in oxidative stress. Studies have shown that autophagy is impaired in the mammary glands of ketotic cows, while enhancing autophagy mitigate oxidative stress in these animals. Cullin3 (CUL3), an E3 ubiquitin ligase, is integral for maintaining cellular homeostasis, particularly regulation of oxidative stress and autophagy. Whether CUL3 is involved in mitigating NEFA-induced oxidative stress is unknown.

Undigested P and N are excreted and contribute to the environmental impacts of dairy farming. Degradation of phytate in the rumen has been shown to be high but variable, leading to incomplete phytate-P utilization and resultant antinutritional impacts of phytate along the gastrointestinal tract. We investigated the effect of a novel bacterial 6-phytase (PhyG) on the apparent total-tract digestibility (ATTD) and excretion of DM, phytate-P (PP), P, CP and NDF in lactating dairy cows. Forty-eight lactating Holstein-Friesian cows were assigned to 3 treatments with 16 cows per treatment in a randomized block design.

Accurate prediction of intestinal digestible flows of EAA (DigFlowEAA) is a crucial step for adequately balancing EAA supply to reduce the amount of CP fed to dairy cows, without compromising either milk production or the health status of the animals. The objective of this meta-analysis was to compare the performance of 3 dairy feed evaluation systems (FES) to predict DigFlowEAA (NRC; National Academies of Sciences, Engineering and Medicine [NASEM]; and Cornell Net Carbohydrate and Protein System version 6.5.5 [CNCPS]) in relation to observed net portal appearance (NPAobs) of EAA.

The negative energy balance (NEB) state in dairy cows is a critical factor affecting health, reproduction, and production, particularly during early lactation. Multiple blood and milk biomarkers change when dairy cows are in the NEB state. Direct measurement of NEB is impractical for large-scale use due to costs, necessitating reliance on indirect predictors such as milk mid-infrared (MIR) spectrometry-based predicted biomarkers. However, the genetic relationships between NEB and its potential biomarkers remain unclear.

Ammonia (NH3) originating from agriculture substantially contributes to the environmental nitrogen load and threatens sensitive ecosystems by inducing eutrophication and acidification of the soil. To strategically minimize NH3 emissions, this study aimed to develop a model to predict urinary nitrogen (UN) excretion (g/d), the major NH3 source of cows of different dairy breeds, based on an easy-to-determine proxy as an on-farm tool. For that purpose, dietary characteristics were not considered. One such proxy would be the MUN content, which could be determined in tank milk samples from dairy farms.

Whey is a liquid byproduct from the dairy industry that is not fully utilized and can be problematic to dispose of. Based on its composition, there is potential to upcycle whey into fermented beverages for human consumption. Most focus to date has been upon alcoholic fermentation to generate alcohol for distillation, or use of kefir grains to make acidic beverages. Kombucha fermentation is analogous to kefir, with a solid-state inoculum that is backslopped from one batch to the next, but yields a different profile of organic acids when applied to its typical substrate of tea sweetened with sucrose.

Well-developed clinical communication is crucial for dairy practitioners in providing effective herd health and production management (HHPM) advisory services, as they have potential to enhance farmer satisfaction and adherence to veterinary advice. However, there is limited knowledge regarding specific communication skills (CS) veterinarians use during HHPM visits. Understanding veterinarians' communication is essential for developing targeted educational interventions to enhance veterinarian-farmer interactions during HHPM visits.

The objective of this study was to investigate the association of postcalving IMI with milk production and SCC during the first 3 test days after calving, as well as the risk of clinical mastitis occurrence and culling within the first 100 DIM in first-lactation Holstein dairy cows. This retrospective cohort study was conducted at one commercial dairy farm in New York. Postcalving IMI was assessed by means of bacteriological testing of composite milk sample aseptically obtained from all quarters at the day of calving or between 7 and 13 DIM.

Mycobacterium avium subspecies paratuberculosis (MAP) is the causative agent for Johne's disease (JD), a chronic, progressive enteritis in ruminants that may lead to substantial weight loss, reduction in milk yield, and eventual death. Due to the very long incubation period, many cattle are culled before presenting signs of clinical infection. Furthermore, poor sensitivity of diagnostic tests results in subclinically infected cattle contributing to the transmission of JD, but otherwise going undetected.

A healthy uterine environment is essential for establishing and maintaining pregnancy and normal embryo development after insemination. In this context, the primary objectives of this study were to assess the genetic background of vaginal discharge score (VDS) traits during the voluntary waiting period in Holstein cows and to identify genomic regions and candidate genes influencing postpartum uterine health based on the integration of phenotypic, genomic, and transcriptomic data sets. Genetic parameters of 5 VDS traits defined according to lactation stage (VDS1, VDS2, VDS3, VDS4, and VDS5) were estimated based on VDS records from 64,241 Holstein cows that calved between 2019 and 2023 and genomic information from 2,489 cows.

Raw milk is known to harbor a complex microbial community, including microorganisms of technological and human health interest. However, it can also be a source of pathogenic and spoilage bacteria, such as spore-forming bacteria and Pseudomonas spp. Despite cleaning and disinfection procedures, biofilms in milking machines are difficult to remove and represent a major source of milk contamination. This work aims to describe biofilms in milking machines at both the laboratory and farm scales. Encouraging studies on the microbiota of milking machine biofilms, the parameters influencing changes in biofilm composition, and the methods used to characterize them are essential for managing the formation and composition of these biofilms.

The fecal metabolome comprises metabolites that are excreted or not absorbed by the animal. This study examined the changes in the fecal metabolome of dairy cows from the end of one lactation period, through the dry period, and into the subsequent lactation. Twelve Holstein cows (BW = 745 ± 71 kg, BCS = 3.43 ± 0.66) were housed in a tie-stall barn from 7 wk before to 15 wk after parturition, with dry-off occurring approximately 6 wk before the expected calving date (mean dry-off time = 42 d). Fecal samples were taken at wk −7, −5, −1, +1, +5, +10, +15 relative to calving.