Journal of Dairy Science

Lactococcus lactis and Lactococcus cremoris strains play a vital role in dairy fermentations, yet their industrial use is threatened by bacteriophage infections that can lead to production failures. Replicative helicases are motor phage proteins driving viral genome replication, and their activity is often supported by accessory proteins involved in helicase recruitment, loading onto DNA, and reg…

The viable but non-culturable (VBNC) state is a stress adaptation strategy in bacteria, characterized by the loss of culturability and reduced metabolism, which may complicate both diagnosis and treatment. This review describes the potential transition of Staphylococcus aureus into a VBNC state during intramammary infections, and in dairy-associated food products. It further distinguishes VBNC ce…

Dairy cattle, particularly in Australia where dairy farming is predominantly pasture based, are experiencing an increased incidence of heat stress through rising global temperatures, causing a detrimental impact on productivity and welfare. Improving the thermotolerance of dairy cows through genetic selection is a potential proactive solution for mitigating the impact of heat stress for the dairy…

A meta-analysis and a meta-regression were conducted to compare DMI, production performance, feed efficiency (FE), and milk N efficiency (milk N yield/N intake) of Holstein and Jersey cows. Only experiments in which purebred Holsteins and Jerseys enrolled in the same study, under similar experimental conditions, were used to build the data sets (n = 30 peer-reviewed articles). The weighted raw me…

The dry period is a critical stage for fetal development, during which maternal nutritional and metabolic status are strongly associated with postnatal growth and organ development in calves. Among metabolic indicators, elevated maternal serum β-hydroxybutyrate (BHB) concentrations during this period have attracted increasing attention; however, their relationships with offspring rumen developmen…

Feruloyl esterase produced by certain microorganisms can help breakdown plant fiber. We investigated effects of inoculating feruloyl esterase-producing lactic acid bacteria (FLAB) in alfalfa silage on production performance and blood and liver markers of inflammation and oxidative stress in lactating dairy goats. Alfalfa was ensiled for 1 mo without additive (control, CON), with Limosilactobacill…

The objective of this study was to compare the cash flow of lactating Holstein cows randomized to health monitoring strategies that relied exclusively on automated health alerts or visual observation for selecting cows for clinical examination from 3 to 21 d in milk (DIM). Data from a randomized controlled trial was used to estimate total cash flow per cow and per slot up to 100 DIM. We expected …

Fermented products, particularly cheese, represent a susceptible reservoir of biogenic amines (BAs), which can pose health risks when present at elevated levels. This study aimed to detect the presence and concentration of 6 major BAs (histamine "Hist," phenylethylamine "Phenyl," cadaverine "Cad," spermine "Sper," spermidine "Sped," and putrescine "Putr") in selected Mediterranean dairy products,…

In the US, non-replacement calves born on dairies are often sold in the first days of life, and experience multiple transport events that increase their risk of disease as they enter the dairy-beef sector. The objectives of this cross-sectional cohort study were to evaluate the condition of dairy-beef calves on arrival at calf-raising farms in the Midwestern US and to identify factors associated …

The consumption of cheese is rapidly increasing, driven by its diverse nutritional and functional benefits. Consumers are shifting toward functional, minimally processed cheese products, enjoyed both on their own and as ingredients in various foods. As cheese undergoes heating processes like grilling and baking, its functionality (e.g., melt, flow, and stretch) become crucial factors in evaluatio…

Wine lees (WLs), a by-product of the wine industry, represent a promising source of bioactive compounds, including diketopiperazines (DKPs). This study aimed to extract, characterize, and evaluate the effects of DKP-enriched WL fractions on immune cell responses under in vitro thermal stress conditions using an ovine model. Wine lees from white, rosé, and red vinifications were subjected to micro…

A long-standing objective in ruminant nutrition is to ensure an adequate supply of the key trace metals Zn, Cu, and Mn, while accounting for bioavailability, nutritional interactions, and not exceeding tolerance. In practice, however, dietary supplementation often by far exceeds reference nutritional guidelines, largely as a precaution against the multiple uncertainties of trace mineral supply. C…

Dry matter (DM) intake (DMI) is one of the most limiting factors for milk production in pasture-based dairy production systems. The inclusion of white clover (Trifolium repens L.) in grass swards can increase voluntary DMI through improved sward nutritive quality and lower resistance to breakdown in the rumen. Feeding a total mixed ration (TMR) can support greater milk production from increased d…

17β-Estradiol (E2), an endogenous estrogen, can be present in milk and may accumulate during processing, potentially contributing to long-term dietary exposure that raises concerns for consumer health. Regulatory agencies have established intake limits to minimize risk, highlighting the importance of reliable monitoring. In this study, we developed a docking-guided dual-mode aptasensor for sensit…

This qualitative study was conducted to explore the perceptions of Canadian dairy veterinarians of continuing education (CE) programs and the factors that influence their participation. Five focus groups were conducted with a total of 20 dairy veterinarians in Canada to discuss their experiences, motivations, and barriers related to participation in CE. Three main themes were identified through a…

This study aims to determine the effects of feeding, management, and reproductive strategies used to reduce age at first calving (AFC) on production and reproductive performance through meta-analytic methods. A literature search using 3 search engines was conducted to identify prospective studies that evaluated AFC for data extraction. Inclusion criteria included specific dairy breeds, a treatmen…

Incretins such as glucagon-like-peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) play crucial roles in postprandial glucose management. GLP-1 and GIP stimulate insulin release in conjunction with meals and are responsible for up to 75% of the insulin secretion. Incretins are therefore very important for maintenance of normal blood glucose levels. Dairy foods are crucial fo…

Heat treatment of milk is an indispensable process for ensuring microbiological safety and extending the shelf life of milk. Ultra high temperature (UHT)-processed milk results in undesirable cooked flavors. An increasing trend exists toward approaches using multivariate analysis based on the concept that flavor is a composite of volatile compounds. This study evaluated whether alternating-curren…

Clinical mastitis (CM) is a complex disease, causing substantial losses to the dairy industry. Observed CM is a binary trait and due to its low incidence, genetic evaluation is challenging. On the other hand, somatic cell counts (SCC) are measured on a regular basis and may aid in the genetic evaluation of udder health. Determining the genetic architecture of udder health traits at different risk…

Energy balance (EB) can be an important health indicator in dairy cows, as a severe or prolonged period of negative energy balance is a key risk factor for metabolic disorders, impaired immune function, and reduced fertility. Understanding the biological mechanisms of energy balance is fundamental to developing strategies that improve energy intake, mitigate negative energy balance, and enhance t…