Journal of Dairy Science

Bile acid profiles and mRNA abundance of bile acid-related genes in adipose tissue of dairy cows with high versus normal body condition

Besides their lipid-digestive role, bile acids (BA) influence overall energy homeostasis, such as glucose and lipid metabolism. We hypothesized that BA along with their receptors, regulatory enzymes, and transporters are present in subcutaneous adipose tissue (scAT). In addition, we hypothesized that their mRNA abundance varies with the body condition of dairy cows around calving. Therefore, we analyzed BA in serum and scAT as well as the mRNA abundance of BA -related enzymes, transporters, and receptors in scAT during the transition period in cows with different body conditions around calving.

Responses to incremental nutrient supply on energy and protein metabolism in pre-weaning dairy calves

Recently reviewed development objectives and feeding practices in young dairy calves require an adaptation of nutrient recommendations set for milk replacer (MR) composition. Nutrient requirements of calves younger than 21 d of age, and those of calves fed with high levels of milk replacer are insufficiently quantified. The efficiency at which macronutrients are utilized, particularly protein, substantially diminishes with age, and there is little data for the first weeks of life. In addition, in older (pre-)ruminants, protein and energy can be simultaneously limiting for protein gain.

High-resolution melting real-time PCR assays for subtyping of five diarrheagenic Escherichia coli by a single well in milk

Diarrheagenic Escherichia coli (DEC) is a kind of foodborne pathogen that poses a significant threat to both food safety and human health. To address the current challenges of high prevalence and difficult subtyping of DEC, this study developed a method that combined multiplex polymerase chain reaction (PCR) with high resolution melting (HRM) analysis for subtyping 5 kinds of DEC. The target genes are amplified by multiplex PCR in a single well, and HRM curve analysis was applied for distinct amplicons based on different melting temperature (Tm) values.

Ameliorating effect of 2ʹ-Fucosyllactose and 6ʹ-Sialyllactose on lipopolysaccharide-induced intestinal inflammation

Human milk oligosaccharides (HMO) affect gut microbiota during neonatal development, particularly with respect to the immune system. Bovine milk-based infant formulas have low oligosaccharide contents. Thus, efforts to fortify infant formulas with HMO are being undertaken. Two major HMO, 2ʹ-fucosyllactose (2ʹ-FL) and 6ʹ-sialyllactose (6ʹ-SL), exert anti-inflammatory effects; however, the associations between anti-inflammatory effects induced by 2ʹ-FL and 6ʹ-SL co-treatment and gut microbiota composition and metabolite modulation remain unclear.

Microbiological, physicochemical and sensory changes throughout ripening of an experimental soft smear-ripened cheese in relation to salt concentrations

To evaluate the sodium chloride content effect on microbiological, biochemical, physicochemical and sensorial characteristics, Munster cheeses were prepared from pasteurized milk seeded with 3 yeasts (Kluyveromyces marxianus, Debaryomyces hansenii, Geotrichum candidum) and 5 ripening bacteria (Arthrobacter arilaitensis, Brevibacterium aurantiacum, Corynebacterium casei, Hafnia alvei, and Staphylococcus equorum). Experiments were performed under 1.0%, 1.7% and 2.4% NaCl levels in cheese in triplicate.

Genetic parameter estimates for methane emission during lactation from breath and potential inaccuracies in reliabilities assuming a repeatability versus random regression model

Methane (CH4) emissions will be added to many national ruminant breeding programs in the coming years. Little is known about the covariance structure of CH4 traits over a lactation, which is important for optimizing recording strategies and to establish optimal genetic evaluation models. Our aim was to study CH4 over a lactation using random regression (RR) models, and to compare the accuracy to a fixed regression repeatability model under different phenotyping strategies. Data were available from repeated measurements of CH4 concentrations (ppm), recorded in the feed bins of milking robots, on 52 commercial dairy farms in the Netherlands.

Effects on mineral status and milking performance of feeding difructose anhydride to transition cows

The objective of this study was to assess the potential effect of difructose anhydride III (DFAIII) on calcemia, magnesemia, and milking performance of dairy cows. Sixty-six multiparous Holstein cows in late pregnancy (gestation days = 253.8 ± 2.13 d) were blocked according to their expected calving date and randomly assigned to either receiving no supplementation (Control) or receiving 40 g/d of DFAIII (DFA) between −14 and +7 d relative to calving following a complete randomized block design. Cows on Control received 640 g/d of a pellet containing no DFAIII, whereas DFA cows received the same pellet but containing 6.25%DFAIII.

A meta-analysis of the relationship between milk protein production and absorbed amino acids and digested energy in dairy cattle.

Milk protein production is the largest draw on AA supplies for lactating dairy cattle. Prior NRC predictions of milk protein production have been absorbed protein (MP)-based and utilized a first-limiting nutrient concept to integrate the effects of energy and protein, which yielded poor accuracy and precision (root mean squared error (RMSE) > 21%). Using a meta-data set gathered, various alternative equation forms considering MP, absorbed total essential AA (EAA), absorbed individual EAA, and digested energy (DE) supplies as additive drivers of production were evaluated, and all were found to be superior in statistical performance to the first limitation approach (RMSE = 14–15%).

Evaluation of the Protective Bioactivity and Molecular Mechanism Verification of Lactoferrin in an Alzheimer's Mouse Model with Ulcerative Enteritis

The development of new drug therapies for Alzheimer's disease (AD) is an important research topic today, but the pathogenesis of AD has not been thoroughly studied, and there are still several shortcomings in existing drug therapies. Therefore, this study aims to explore the molecular mechanism of lactoferrin in the treatments of AD and ulcerative colitis (UC) which are susceptible to AD, starting from the principle of “one drug, two diseases, and the same treatment.” This study used pathological staining and specific indicators staining to preliminarily evaluate the interventions of lactoferrin on UC injury and AD progression.

A living lab approach to understanding dairy farmers' needs of technologies and data to improve herd health: Focus groups from 6 European countries

For successful development and adoption of technology on dairy farms, farmers need to be included in the innovation process. However, the design of agricultural technologies usually takes a top-down approach with little involvement of end-users at the early stages. Living Labs offer a methodology that involve end-users throughout the development process and emphasize the importance of understanding users' needs. Currently, exploration of dairy farmers' needs of technologies has been limited to specific types of technology (e.g., smartphone apps) and adult cattle.

Alginate/whey protein isolate-based emulgel as an alternative margarine replacer in processed cheese: Impact on rheological, mechanical, nutritional, and sensory characteristics

Effects of partial or full replacement of margarine by alginate/whey protein isolate-based olive oil emulgel (E) on nutritional, physicochemical, mechanical, and rheological properties of processed cheese (PC) were investigated in this work. All formulated samples had the same amount of total fat, dry matter, and pH. According to the results of the fatty acids profile, the processed cheese sample in which the margarine was fully replaced by the emulgel (EPC100) had the highest (49.84%) oleic acid content and showed a reduction of 23.7% in saturated fatty acids compared with the control sample (EPC0: formulated just with margarine).

Signatures of positive selection after the introduction of genomic selection in the Finnish Ayrshire population

The Finnish Ayrshire (FAY) belongs to the Nordic Red breeds and is characterized by high milk yield, high milk components, good fertility, and functional conformation. The FAY breeding program is based on genomic selection. Despite the benefits of selection on breeding values, autozygosity in the genome may increase due to selection, and increased autozygosity may cause inbreeding depression in selected traits. However, there is lack of studies concerning selection signatures in the FAY after genomic selection introduction.

MECHANISMS BY WHICH FEEDING SYNTHETIC ZEOLITE A AND DIETARY CATION ANION DIFFERENCE DIETS IMPACT FEED INTAKE, ENERGY METABOLISM, AND MILK PERFORMANCE: PART II.

The objectives of this study were to assess the effects of feeding 2 different diets, a low dietary cation-anion difference (DCAD) or a diet with synthetic zeolite A to multiparous Holstein cows during the close-up period on DMI and energy metabolism, as well as evaluate colostrum and milk production. A hundred and 21 multiparous Holstein cows, blocked by lactation number and expected parturition date were enrolled at 254 d of gestation and randomly assigned to 1 of 3 dietary treatments: control (CON; +190 mEq/kg; n = 40), negative DCAD (DCAD, −65 mEq/kg; n = 41; Ultra Chlor; Vita Plus, Lake Mills, WI, USA), or a diet containing sodium aluminum silicate zeolite (XZ; +278 mEq/kg, fed at 3.3% DM, targeting 500 g/day; n = 40; X-Zelit, Protekta Inc., Lucknow, ON, Canada/Vilofoss, Graasten, Denmark).

MECHANISMS BY WHICH FEEDING SYNTHETIC ZEOLITE A AND DIETARY CATION ANION DIFFERENCE DIETS IMPACT MINERAL METABOLISM IN MULTIPAROUS HOLSTEIN COWS: PART I

The periparturient period is characterized by the increased demand for calcium (Ca) in dairy cows. This has resulted in the utilization of several different prepartal nutritional strategies to prevent hypocalcemia postpartum. The objective of our study was to determine the effects of feeding synthetic zeolite A (XZ), a negative dietary cation-anion difference (DCAD) diet, or a positive DCAD diet (CON) during the close-up period on peripartal mineral dynamics and hormones involved in calcium metabolism.

Genomic inbreeding coefficients using imputation genotypes: assessing the effect of ancestral genotyping in Holstein-Friesian dairy cows

The objective of this study was to assess the effect of using or not the genotypes of the parents of a cow for imputing single nucleotide polymorphisms (SNP), on the estimation of genomic inbreeding coefficients of cows. Imputation (i.e., genotyped plus imputed) genotypes from 68,127 Italian Holstein dairy cows registered in the Italian National Association of Holstein, Brown and Jersey Breeders (ANAFIBJ) were analyzed. Cows were genotyped with the HD Illumina Infinium BovineHD BeadChip and GeneSeek Genomic Profiler HD-150K, and the MD GeneSeek Genomic Profiler 3, GeneSeek Genomic Profiler 4, GeneSeek MD and the Labogena MD.

Ontario dairy producers' and veterinarians' perspectives: barriers to biosecurity implementation

Implementing biosecurity protocols is necessary to reduce the spread of disease on dairy farms. In Ontario, biosecurity implementation is variable among farms and barriers to biosecurity are unknown. Thirty-five semi-structured interviews were conducted between July 2022 and January 2023 with dairy producers (n = 17) and veterinarians (n = 18). Participants also completed a demographic survey. Thematic analysis was performed with constructivist and grounded theory paradigms. Thematic coding was done inductively using NVivo software.

Effects of feeding whole-cracked rapeseeds, nitrate, and 3-nitrooxypropanol on composition and functional properties of the milk fat fraction from Danish Holstein cows

The aim of this study was to determine the individual and combined effects of supplementing fat (FAT), nitrate (NITRATE) and 3-nitrooxypropanol (3-NOP) on compositional and functional properties of milk fat. An 8 × 8 incomplete Latin square design was conducted with 48 lactating Danish Holstein cows over 6 periods of 21 d each. Eight diets were 2 × 2 × 2 factorially arranged: FAT (30 or 63 g crude fat/kg DM), NITRATE (0 or 10 g nitrate/kg DM), and 3-NOP (0 or 80 mg 3-NOP/kg DM) and cows were fed ad libitum.

Can a gradual weaning and separation process reduce weaning distress in dam-reared dairy calves? A comparison with the two-step method.

The weaning and separation phase remains one of the biggest challenges for cow-calf-contact systems, but a gradual process that better mimics the naturally occurring reduction in milk intake has not yet been scientifically investigated. Therefore, the aim of our study was to compare behavioral and physiological indicators of distress in 3 mo-old dam-reared dairy calves (with previous full-time cow-calf contact) weaned and separated either via gradual reduction of contact time with the dam (GR, 1 week half day contact, 1 week morning contact, 1 week fence-line contact before complete separation, n = 18) or via 2-step weaning using a nose flap (NF, 2 weeks access to dam with a nose flap, 1 week fence-line contact before complete separation, n = 18).

An integrated approach to explore the microbial biodiversity of natural milk cultures for cheesemaking

The use of natural milk culture (NMC) represents a key factor in PDO Montasio cheeses, contributing to its distinctive sensory profile. The complex microbial ecosystem of NMCs is the result of heat treatment and incubation conditions, which can vary considerably among different production plants. In this study, the microbiota of NMCs collected from 10 PDO Montasio cheese dairies was investigated employing colony counts and metagenomic analysis. Furthermore, residual sugars, organic acids, and volatile profiles were quantitatively investigated.

Reduction in the antigenicity of beta-lactoglobulin in whole milk powder via supercritical CO2 treatment

Cows' milk allergy (CMA) is a common phenomenon experienced in early childhood (<5 years of age) with an average occurrence rate of roughly 2.5%. The most prevalent allergen in cows' milk is believed to be β-lactoglobulin (β-LG). The objective of this study was to evaluate the use of hydrophobic supercritical CO2 (ScCO2) to modify the chemical structure β-LG thus impairing its recognition by antibodies. Whole milk powder was selected because of its closest compositional resemblance to bovine fluid milk and its applications in reconstitution and in the beverage (infant, toddler, and adult), confectionary, bakery, and meat industries.

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