Journal of Dairy Science

Impact of a native rumen microbe supplement provided in feed on production performance and enteric methane emissions in lactating dairy cows

The objective of this randomized controlled study was to evaluate the effects of a native rumen microbial feed supplement on production performance (milk production, milk composition, and feed efficiency). Additionally, the effects of the microbial supplement on enteric methane emissions were assessed. Forty-six second-, third-, and fourth-parity Jersey cows at 59 ± 8 DIM were blocked by baseline milk yield and randomly assigned to control (no microbial supplementation) or treatment (GF-MFS; TMR containing 5 g/cow per day of a native rumen microbial feed supplement containing a minimum of Clostridium beijerinckii at 2 × 106 cfu/g, Pichia kudriavzevii at 2 × 107 cfu/g, Ruminococcus bovis at 2 × 107 cfu/g, and Butyrivibrio fibrisolvens at 2 × 107 cfu/g).

Multidimensional evaluation of the similarity between infant formulas and human milk based on macronutrients, fatty acid composition and positional distribution, and sn-2 palmitoyl triacylglycerols

A multidimensional similarity evaluation was conducted between 12 commercial infant formulas (6 1,3-dioleoyl-2-palmitoylglycerol [OPO]-fortified samples; 6 nonfortified samples) and 205 human milk samples from Hainan Island, China, in this study. The results showed that 12 brands of infant formulas had high similarity scores to human milk at the nutrient composition and energy supply (GNE > 88), total fatty acid composition (GFA > 80), and sn-2 palmitoyl triacylglycerol (GOPO and GOPL > 82) levels.

Use of milk powders to manufacture panela cheese by a wheyless cheesemaking process

Manufacturing cheese using only milk powders (not liquid milk) and a wheyless process could be highly beneficial for developing nations, owing to the limited availability of fresh milk and the lack of proper whey handling equipment. A wheyless process, using milk powders, is very challenging for semihard cheeses because it requires the rehydration of milk powders to very high protein levels (≥20%). The solubility and rennet coagulation properties of a range of commercial high-protein milk powders were evaluated.

Associations of diarrhea and bovine respiratory disease with growth, feed intake, and mortality during the preweaning period of Holsteins and beef-on-dairy calves

Diarrhea and bovine respiratory disease (BRD) are the most common illnesses affecting calves during the preweaning period. This retrospective cohort study aimed to evaluate the associations of diarrhea and BRD with ADG, relative ADG (relADG; % of ADG relative to mid-point BW), milk replacer refusal (MRR), starter intake, and mortality in Holstein and beef-on-dairy (BxD) calves during the first 56 d of life. A total of 240 newborn calves (114 Holstein and 126 BxD) were enrolled between September 2023 and March 2024, and were housed individually for 56 d, bottle-fed with 6L/d of milk replacer and had ad libitum access to calf starter and water.

Prediction and genetic analysis of blood β-hydroxybutyrate based on milk mid-infrared spectra in Fleckvieh dairy cows

Hyperketonemia is a common metabolic disorder in early-lactation dairy cows that impairs milk performance and health. The gold-standard indicator for diagnosis is the blood metabolite BHB. However, measuring blood BHB on a large scale is cumbersome and expensive, resulting in a paucity of available phenotypes, therefore precluding hyperketonemia from most genetic evaluation systems. An alternative approach is the prediction of blood BHB concentration from milk mid-infrared (MIR) spectra. Thus, the objectives of the present study were to develop prediction equations for blood BHB concentration using milk MIR spectroscopy and to estimate genetic parameters of and among MIR-spectra-predicted BHB (MIR-BHB), milk production traits, blood BHB, and clinically diagnosed ketosis.

Automatic milking unit preference of Holstein, Jersey, and Holstein-Jersey crossbred cows in a batch milking system

The efficiency of automatic milking systems depends on the continuous flow of cows, which may be affected by specific cow conducts, including milking unit preference. Moreover, providing resources that favor the expression of natural cow behaviors during the milking process may result in improved animal welfare. The objective of this study was to analyze the selection behavior for automatic milking units, comparing preference consistency across the lactation of 3 genetic groups (Holstein [HO], Jersey [JE], and Holstein × Jersey [HJ]) in a multibreed organic dairy farm using a batch milking system.

Effect of cutting height on the nutritive value, dry matter yield, and fermentation profile of whole-plant corn forage and silage through a meta-analysis

The objectives of this study were to (1) evaluate the effect of cutting height during harvest on the nutrient composition, fermentation profile, and DM yield of whole-plant corn forage and silage and (2) evaluate the effect of cutting height on these variables at different DM at harvest categories. Data from 35 studies and 151 observations met the selection criteria, and 33 studies and 134 observations reported DM at harvest or DM of silage. Data were classified as low (LO; <32% DM; 42 observations from 15 studies), average (AVG; 32% to 37% DM; 52 observations from 14 studies) or high (HI; >37% DM; 29 observations from 9 studies) DM at harvest and the effect of cutting height was evaluated within each subset of DM at harvest, in addition to the full dataset.

Antibiotic resistance profile and molecular mechanism of enterococci in traditional fermented yogurts

Enterococci are present in traditional fermented foods, but their potential role as reservoirs of antibiotic resistance and virulence genes has raised concerns about food safety. To evaluate the prevalence of antibiotic-resistant enterococci in traditional fermented yogurt, microbial sequencing and culture methods were used to analyze the microbiota and Enterococcus composition in a total of 75 yogurts from Xinjiang Uygur Autonomous Region (Xinjiang, China). Enterococcus faecium and Enterococcus durans were the predominant enterococcal species and belonged to 20 and 5 biotypes, respectively, according to randomly amplified polymorphic DNA PCR analysis.

Impact of farming systems and welfare indicators on enteric methane emissions calculated from infrared-predicted milk fatty acids in Parmigiano Reggiano Consortium farms

Enteric methane emissions (EME) are the main source of anthropogenic GHG in the dairy industry. Certified food products, such as Parmigiano Reggiano cheese, are particularly interested in monitoring their environmental impact. To achieve this, a rapid, cost-effective method, applicable at the population level, is to estimate EME from predicted milk fatty acids obtained by milk mid-infrared spectroscopy. The aim of this study was to evaluate the variation in EME-derived traits according to dairy system and farm-level animal welfare indicators in farms belonging to the Parmigiano Reggiano Consortium.

Effect of feeding almond hulls on energy partitioning, nutrient balance, milk yield, and methane emissions in lactating dairy goats

Almond hulls are a rich source of triterpenoids (betulinic, urosolic, and oleanolic acids), flavonols, phenolics, catechins, and other polyphenolic compounds, some of which have antibacterial and antioxidant activity. The aim of this study was to evaluate the effects of incorporating almond hulls into the compound feed of diets for dairy goats on milk performance, methane emissions, and energy partitioning. Ten Murciano-Granadina dairy goats (n = 5/group) in late lactation were used in a crossover design experiment (2 treatments across 2 periods).

Characterization of thermostable β-glucosidase immobilized on linen fabric

In this study, a thermostable β-glucosidase derived from a hot spring metagenome was successfully immobilized on linen fabric to create an eco-friendly and reusable biocatalyst for lactose hydrolysis. The enzyme is derived from a metagenome of the high-temperature Pisciarelli hot springs, an extreme environment known to yield robust biocatalysts with industrial relevance. Two immobilization strategies were employed: direct covalent binding (Lf-β-glucosidase) and binding via a spacer arm (LfEG-β-glucosidase).

Graduate Student Literature Review: Screening, degradation mechanisms, and applications in dairy products of cholesterol-lowering lactic acid bacteria—A review*...

Hypercholesterolemia, a key culprit in cardiovascular diseases, poses challenges due to the limitations of current therapies, including adverse effects and poor long-term adherence. Lactic acid bacteria (LAB), lauded for their safety, versatile mechanisms, and broad applicability across food, pharmaceutical, and livestock sectors, emerge as a promising natural alternative for cholesterol management. This study provides a comprehensive overview of the role of cholesterol and the risk of high intake, screening of cholesterol-lowering LAB and their in vitro and in vivo degradation mechanisms, and further summarizes the potential of their application in dairy products.

Effects of different vaccination schedules prior to dry-off on systemic inflammation, immunity, and subsequent performance of dairy cows

This study aimed to evaluate the effects of different vaccination schedules before dry-off (DO) on systemic inflammation and immunity during the early dry period and performance in the subsequent lactation in primiparous (PRIM) and multiparous (MULT) Holstein dairy cows in a commercial dairy farm. Farm standard operating procedure included administering vaccines (Enviracor J-5, ScourGuard 4KC, Ultrabac 7/Somubac, Zoetis) 2 d before DO and relocating to pasture where cows were fed only hay and milked once per day until DO.

Using time-temperature recorder data on dairy farms to identify short-term factors associated with increased free fatty acids in bulk tank milk

Elevated concentrations of free fatty acids (FFA; ≥1.20 mmol/100 g of fat) reduce milk quality by changing milk sensory and functional properties. Bulk tank FFA levels vary between milk pickups, and there is limited research to identify factors associated with these short-term fluctuations in FFA. A time-temperature recorder (TTR) may be used on dairy farms to identify milk quality concerns through producer alarms related to milk cooling, storage, and contact surface sanitization. The objective of this study was to investigate whether specific TTR alarms could be associated with short-term increases in bulk tank milk FFA.

Enteric methane, manure composition, and anaerobic digestor methane potential in lactating cows fed diets differing in substitution of dried distillers grains and solubles

Two experiments were conducted to evaluate enteric methane, manure composition, and digestor methane potential in lactating cows fed diets differing in substitution of dried distillers grains and solubles (DDGS). The objectives of experiment 1 were to examine the effects of feeding DDGS by reducing dietary starch, NDF, and forage NDF (fNDF) on enteric methane production, feed intake, energy and N utilization, manure output, and milk production in lactating Jersey cows. Twelve multiparous Jersey cows (98 ± 6.5 DIM and weighing 441 ± 26.9 kg) were arranged in a triplicated 4 × 4 Latin square design consisting of 4 periods of 28 d.

Scalar methods to deregress and split genomic predictions, and associated behavior of simple regressions, for later use in combined prediction and validations

Scalar deregressions are used in dairy cattle to postprocess genetic evaluations into early and late, or separate, pieces of information. These separate pieces of information are in turn used, for example, to include foreign information or for validation of the genomic evaluation procedure. Here we detail the scalar algebra to separate “partial” evaluations from “whole,” with associated breeding values and reliabilities, into equivalent deregressed proofs (pseudophenotypes) and equivalent record contributions (pseudonumber of observed phenotypes).

Supplemental UV-B lighting to naturally enhance the vitamin D content of milk of housed dairy cows

The increasing incidence of vitamin D deficiency in Europe has generated interest in naturally enhancing vitamin D levels in commonly consumed foods, such as milk, by biofortification (defined here as increasing the concentration of a specific nutrient in a food by changing the diet or management of an animal). Endogenous, solar-driven biosynthesis of vitamin D is a potentially modifiable option for boosting vitamin D concentrations in milk. The objective of this study was to quantify milk and plasma vitamin D responses in housed cows exposed to artificial UV-B light over 12 wk.

Udder health management, bacteriological culturing and antimicrobial use: Knowledge, implementation, attitude, and opinion among Flemish bovine dairy producers

Through an online questionnaire, we evaluated knowledge, implementation, interest, attitudes, and opinion regarding udder health management, bacteriological culturing (BC) of milk samples, and antimicrobial use among Flemish bovine dairy producers. Data were analyzed using descriptive statistics, contingency tables, and multiple correspondence analysis. Most strikingly, 75% of the 126 participants were not able to differentiate clinical mastitis (CM) from subclinical mastitis (SCM) despite many years of knowledge dissemination through a multitude of channels.

Impact of lactose and soluble milk salts on the heat stability of milk proteins

Our objective was to determine the separate effects of lactose, soluble mineral concentration, and added dipotassium phosphate (DKP) on the heat stability of milk protein beverages made from rehydrated milk protein concentrate (MPC) with 85% crude protein on a DM basis (MPC85). Seven batches of rehydrated (7.5% protein) liquid MPC were made from each of 2 lots of MPC85 powder. Treatment 1 was 7.5% MPC85 in deionized (DI) water. Treatment 2 was 7.5% MPC85 that was rehydrated with 4°C Jenness–Koops (JK) buffer, a mix of salts that simulate milk salts.

Dairy farmers' perception of barriers associated with the uptake of educational programs: A qualitative focus group study in Ontario, Canada

This qualitative study explored Ontario dairy farmers' perceptions of educational programs and the factors that influenced their participation. Five focus groups were conducted with 20 dairy producers in southern Ontario to discuss their experiences, motivations, and barriers related to educational program participation. Through applied thematic analysis, 3 main themes were identified: (1) strategies for effective outreach and engagement, (2) perceived value of education as a driver for progress, and (3) participation in educational programs: motivators, barriers, and preferences.

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