Journal of Dairy Research最新文献

The aim of this experiment was to investigate the differential proteomic characteristics of milk from high- and low-yielding Guanzhong dairy goats during the peak lactation period under the same feeding conditions. Nine Guanzhong dairy goats with high yield (H: 3.5 ± 0.17 kg/d) and nine with low yield (L:1.2 ± 0.25 kg/d) were selected for milk proteomic analysis using tandem mass tag technology. A total of 78 differentially expressed proteins were identified. Compared with L, 50 proteins including HK3, HSPB1 and ANXA2 were significantly upregulated in H milk, while 28 proteins including LALBA and XDH were significantly downregulated. Bioinformatics analysis of the differentially expressed proteins showed that galactose metabolism, purine metabolism, glycolysis/gluconeogenesis, MAPK signaling pathway, regulation of actin cytoskeleton and other pathways were closely related to milk yield. HK3, HSPB1, ANXA2, LALBA and XDH were important candidate proteins associated with the milk production characteristics of Guanzhong dairy goats. Our data provide relevant biomarkers and a theoretical basis for improving milk production in Guanzhong dairy goats.

This research paper addresses the hypotheses that Kluyveromyces marxianus can be cultured with good alcohol production on different whey-derived matrices, and that the fermented product can be used in order to develop alcoholic beverages with acceptable sensory characteristics by mixtures with yeast-fermented fruit-based matrices. Growth and fermentative characteristics of Kluyveromyces marxianus LFIQK1 in different whey-derived matrices were explored by culturing (24 h, 30°C) on reconstituted whey, demineralized whey, heat-treated whey and milk permeate media. High lactose consumption, ethanol production and yield were observed. Reconstituted whey matrix was selected for mixing with orange or strawberry juices fermented using Saccharomyces cerevisiae to obtain alcoholic beverages (W-OR and W-ST, respectively). Consumer evaluation of beverages was performed using acceptability and Check-All-That-Apply (CATA) questions. Good acceptance was observed, significantly higher for W-ST than for W-OR. CATA questions gave information about organoleptic characteristics of beverages. Penalty analysis showed W-R and W-ST were positively associated with smooth/refreshing and fruity/natural, respectively. Liking was represented, accordingly with penalty analysis, by natural/refreshing. A novel alternative for utilization of whey and whey-related matrices by alcoholic beverages production with natural ingredients is presented.

We investigated the antimicrobial components in cow milk at dry off and postpartum and their contribution in preventing new high SCC at quarter level. Milk samples from 72 quarters of 19 lactating cows were collected at last milking before dry off and at 7 d after parturition. Milk yield of each cow was recorded and SCC, IgG, IgA, lactoferrin, lingual antimicrobial peptide (LAP), and S100A7 concentrations in each quarter milk sample were measured. The postpartum milk yield was significantly higher than that at dry off. The IgG, IgA and lactoferrin concentrations in milk at dry off were significantly higher than those at postpartum, whereas the LAP concentration was lower. Quarters with SCC < 300 000 cells/ml at both dry off and postpartum were classified as persistent low SCC (PL) whereas those that rose above that same threshold postpartum were classified as new high SCC (NH). At dry off, IgG and LAP concentrations in milk were significantly higher in PL than in NH. These results suggest that high LAP concentrations during the dry period may contribute toward the prevention of new high SCC.

The purpose of this paper is to understand the milk processing system practiced in the Mongolian nomadic Khalkha groups of Su'qbaatar and Dornod Provinces in eastern Mongolia through a field survey, to compare it with surrounding areas of Qentiy and Dundgowi Provinces, and then to analyze the transmission of processing techniques by further comparison with those of Syria, Jordan, Iran and Iraq in West Asia. The milk processing techniques of fermentation, cream separation and additive coagulation are all used in Su'qbaatar and Dornod Provinces. In fermentation processes, the technique of alcohol fermentation with churning is mainly used for cow milk to process alcoholic sour milk, followed by further processing to spirit, butter oil and non-matured dry cheese. In cream separation processes, the technique of heating/cream separation is used, in which cream is first separated from milk and non-matured dry cheese is processed from skim milk. In additive coagulation processes, the technique of fermented milk coagulation which utilizes lactic acid fermented whey as a coagulant is used to process non-matured dry cheese. These techniques are widely shared in the eastern part of Mongolia. It is characteristic of Su'qbaatar Province that the processing of cow milk is dominated by the technique of fermentation processes, mainly alcohol fermentation with churning. It is presumed that the technique of churning sour milk transmitted from West Asia to eastern Mongolia, and then the function of churning originally for butter processing was converted to allow for alcohol fermentation under the cooler environment in North Asia.

The objective of this study was to determine the effect of dietary calcium soaps from garlic (Allium sativum) and willow (Salix babylonica) extracts on nematode loads, nutrient intake and digestibility, nitrogen balance and rumen fermentation kinetics in dairy goats. Nine adult non-lactating Saanen goats were grouped into a complete randomized block design with 3 treatments (n = 3) over a period of 28 d. Animals were fed a diet based on alfalfa hay and a concentrate that was supplemented (65 g/kg DM) with calcium soaps of safflower (control), garlic or willow. Intake of dry matter (DM), organic matter (OM) and neutral detergent fiber (NDF) were not affected by dietary calcium soaps. However, the highest digestibility of DM and OM were observed in willow supplemented goats. In vitro gas kinetics and fermentation profile were not affected by diets. Results from fecal egg count indicated a reduction in total count, Haemonchus spp. and Trychostrongylus spp. for both garlic and willow compared to control. Our results suggest that calcium soaps of garlic or willow extracts can be used to reduce gastrointestinal parasites in goats without compromising productive traits or rumen function.

Rapid diagnostic tests that differentiate between Gram positive, Gram negative and the absence of aerobic bacteria in milk samples from dairy cows with clinical mastitis can support antimicrobial treatment decisions and contribute to a more prudent use of antimicrobials in the dairy industry. The objective of this study was to evaluate the test characteristics of the novel rapid BACT mastitis test in discriminating causes of clinical mastitis under laboratory conditions. Test outcomes of 155 milk samples from clinical mastitis cases were incubated for 14-16 h in the BACT test and compared to results of bacteriological culture. The accuracy for detection of bacterial growth and Gram positive growth was 91 and 89%, respectively. The BACT test could provide an accurate and relatively fast decision tool for farmers to aid in antimicrobial treatment decisions in cases of clinical mastitis.

The study was carried out in dairy cows to elucidate whether treatment of clinical mastitis quarters with Spectramast® LC (ceftiofur hydrochloride, 125 mg, Zoetis) created a reason for discarding milk from adjacent untreated healthy quarters. The antibiotic was infused once daily in the affected mammary quarter for four days. Forty-nine cows were evaluated after diagnosis of clinical mastitis in three or fewer udder quarters. In all cases, quarters that did not receive treatment had milk samples collected one day after the end of treatment. All milk samples from untreated quarters were below the maximum permissible limit for the presence of antibiotic residues after analysis with the BetaStar S Combo test. Pharmacokinetic and pharmacodynamic characteristics may explain this finding. We conclude that it is feasible to use milk from untreated quarters of animals that have been treated with Spectramast® LC. We also reiterate the need to carry out tests with other pharmacological bases, and that the results found in this experiment cannot be extrapolated to other drugs.Dairy cattle have considerable importance in the development of the Brazilian economy, being directly linked to economic and social progress. In the first half of 2020, 12.1 billion liters of milk were produced in Brazil and in 2019, there was a new record of 25.01 billion liters produced (IBGE, 2020). This production comes from a wide variety of production systems, coming from smallholder farmers as well as from large companies that use the latest technologies available on the market. Dairy production is a complex activity. For one to obtain economical success, several aspects must be monitored. Maintaining the health of animals is a top priority, and the literature suggests that various diseases are a common challenge for dairy producers. Mastitis is the main disease that affects dairy cows, responsible for considerable economic loss and significant zootechnical and productive challenges (Ruegg, ). It is considered the second leading cause of cow culling in dairy herds, behind reproductive problems. Mastitis is characterized by infection of the mammary gland and may or may not occur with inflammation, generating changes in the mammary tissue and properties of the milk. It is classifield into clinical or subclinical mastitis, according to presence or absence of clinical signs, and into contagious or environmental based on the causative agent (Correa et al., ).

Our objectives were to quantify the dimensions of a fully 'closed' teat canal in dry cows and to describe recovery of the teat canal between milkings in lactating cows to assess whether and when full closure is attained, since this is an important determinant of udder health. Using an ultrasound scanner, teat canal length and diameter (proximal, midpoint and distal), teat cistern width, teat end width, whole teat width and teat wall thickness in 77 dry and 39 lactating dairy cows were measured. The dry cows represented a cross section of the dry population, with days since dry off ranging from 0 to 69 (median: 27). Data from lactating cows were recorded just before milking, and every 3 h post-milking. To control for location a cross-over (parlour vs. barn) study design was used. In dry cows, teat canal length and diameter did not vary by quarter or days since dry off, but multiparous cows had significantly wider teat canals than primiparous cows. The dry cow measurements can be used as baseline for dimensions for closed teats. In lactating cows, all teat dimensions except teat end width changed significantly during the 12-h milking cycle. Location (parlour vs. barn) did not affect the measurements, except teat end width and teat wall thickness. Teat canal length increased after milking and returned to pre-milking values by 9 h. Proximal and midpoint teat canal diameters decreased slightly just after milking and then progressively increased to above the pre-milking values by 9 h. Distal teat canal diameter increased after milking, partially contracting by 9 h. We found that during the dry period the teat canal is in a steady state, but its diameter is not zero, while during the lactation, the teat canal is in a near constant state of remodelling.