Milk Weight Research Articles

Human Milk-Based or Bovine Milk-Based Fortifiers Differentially Impact the Development of the Gut Microbiota of Preterm Infants.

Background: Preterm infants are exposed to different dietary inputs during their hospitalization in the neonatal intensive care unit (NICU). These include human milk (HM), with a human milk-based (HMF) or a bovine milk-based (BMF) fortifier, or formula. Milk consumption and the type of fortification will cause changes in the gut microbiota structure of preterm infants. This study aimed to characterize the gut microbiota of PT infant according to the type of feeding and the type of HM fortification and its possible association with infant's growth.Methods: Ninety-seven infants born ≤33 wks of gestation or <1,500 g were followed during the hospitalization period in the NICU after birth until discharge. Clinical and dietary information was collected, including mode of delivery, pregnancy complications, mechanical ventilation, use of antibiotics, weight, and type and amount of milk consumed. To characterize the gut microbiota composition, weekly stool samples were collected from study participants. The V3–V4 region of the 16S rRNA bacterial gene was Sequenced using Illumina MiSeq technology.Results: After birth, black maternal race, corrected gestational age (GA) and exposure to pregnancy complications, had a significant effect on gut microbial diversity and the abundance of Enterococcus, Veillonella, Bifidobacterium, Enterobacter, and Bacteroides. Over the course of hospitalization, corrected GA and exposure to chorioamnionitis remained to have an effect on gut microbial composition. Two different enterotypes were found in the gut microbiota of preterm infants. One enriched in Escherichia-Shigella, and another enriched in uncharacterized Enterobacteriaceae, Klebsiella and Clostridium sensu stricto 1. Overall, HM and fortification with HMF were the most common feeding strategies. When consuming BMF, PT infants had higher growth rates than those consuming HMF. Milk and type of fortification were significantly associated with the abundance of Clostridium sensu stricto 1, Bifidobacterium and Lactobacillus.Conclusions: This observational study shows the significant association between milk consumption and the exposure to HMF or BMF fortification in the fecal microbiota composition of preterm infants. Additionally, these results show the effect of other perinatal factors in the establishment and development of PT infant's gut microbiota.

525 Late-Breaking: Late Gestational Nutrient Restriction of Primiparous Beef Heifers Decreases Milk Yield and Pre-weaning Calf Growth

Abstract Fall-calving Hereford-SimAngus heifers (single-sired; BW: 451 ± 28 [SD] kg; BCS: 5.4 ± 0.7) bred to a single sire were individually-fed 100% (control; CON; n = 12) or 70% (nutrient restricted; NR; n = 13) of NASEM net energy and metabolizable protein requirements for maintenance, pregnancy, and growth from d 160 of gestation to calving. Post-calving, all females were limit-fed chopped tall-fescue hay supplemented to meet lactational nutrient requirements in Calan gates to constrain calves’ diets to milk only until d 147. Four-hour milk yields were measured 5 times; calf size was determined every 21 d. Data were analyzed with treatment, calving date, and calf sex (when P &amp;lt; 0.25) as fixed effects; day and day x treatment were included for milk yield. From calving to d 147, CON cows had greater (P ≤ 0.003) BW, BCS, and backfat, but NR cows gained more (P ≤ 0.004) BW, BCS, and backfat. Milk weight and volume was 15% less (main effect; P &amp;lt; 0.04) for NR cows. Calf size did not differ at birth (P ≥ 0.27). From d 42 to 147, calves born to NR dams had lower (P ≤ 0.02) BW. Heart, abdominal, and flank girths were less (P ≤ 0.07) for NR calves through d 147. Calf ribeye area tended to be less (P ≤ 0.11) in NR calves at d 42, 84, and 126. Nutrient restricted calves had less shoulder to rump length (d 63 to 147; P ≤ 0.08), shoulder height (d 63 to 126; P ≤ 0.02), cannon length (d 42 to 105 and 147; P ≤ 0.09), and cannon circumference (d 63 and 105 to 147; P ≤ 0.06). These data indicate that even when dams are fed to meet lactational requirements, milk yield and calf growth are reduced by late gestational nutrient restriction.

EFFECT OF TRANSGLUTAMINASE TREATMENTON TRANSITION OF SOLIDS FROM MILK TO CHEESE

Transglutaminase is an enzyme that forms cross-links between protein molecules and affects such protein properties as the ability to gel, thermal stability, water retention, etc. One of the important tasks of the food industry is to increase the yield of products, in particular soft cheeses, in the production of which a significant part of the whey with dissolved substances is separated from milk. Therefore, the aim of the work was to study the effect of transglutaminase on the transition of milk solids to cheese, depending on the stage of application of the enzyme. Transglutaminase in an amount of 0.05% by weight of milk (1.6 units in terms of 1 g of protein) was introduced in two versions: simultaneously with the milk-clotting enzyme and after cutting the clot. It was found that the use of transglutaminase does not affect the duration of acid-rennet coagulation of milk. The data obtained indicate that when transglutaminase is introduced into milk simultaneously with the milk-converting enzyme, the transition of milk solids to cheese increases by 5.15%, including fat by 3.07%, compared to samples without transglutaminase. When transglutaminase is added at the stage of processing the clot, a denser consistency of cheese is formed.

Genetic parameters of differential somatic cell count, milk composition, and cheese-making traits measured and predicted using spectral data in Holstein cows

Mastitis is one of the most prevalent diseases in dairy cattle and is the cause of considerable economic losses. Alongside somatic cell count (SCC), differential somatic cell count (DSCC) has been recently introduced as a new indicator of intramammary infection. The DSCC is expressed as a count or a proportion (%) of polymorphonuclear neutrophils plus lymphocytes (PMN-LYM) in milk somatic cells. These numbers are complemented to total somatic cell count or to 100 by macrophages (MAC). The aim of this study was to investigate the genetic variation and heritability of DSCC, and its correlation with milk composition, udder health indicators, milk composition, and technological traits in Holstein cattle. Data used in the analysis consisted in single test-day records from 2,488 Holstein cows reared in 36 herds located in northern Italy. Fourier-transform infrared (FTIR) spectroscopy was used to predict missing information for some milk coagulation and cheese-making traits, to increase sample size and improve estimation of the genetic parameters. Bayesian animal models were implemented via Gibbs sampling. Marginal posterior means of the heritability estimates were 0.13 for somatic cell score (SCS); 0.11 for DSCC, MAC proportion, and MAC count; and 0.10 for PMN-LYM count. Posterior means of additive genetic correlations between SCS and milk composition and udder health were low to moderate and unfavorable. All the relevant genetic correlations between the SCC traits considered and the milk traits (composition, coagulation, cheese yield and nutrients recovery) were unfavorable. The SCS showed genetic correlations of -0.30 with the milk protein proportion, -0.56 with the lactose proportion and -0.52 with the casein index. In the case of milk technological traits, SCS showed genetic correlations of 0.38 with curd firming rate (k20), 0.45 with rennet coagulation time estimated using the curd firming over time equation (RCTeq), -0.39 with asymptotic potential curd firmness, -0.26 with maximum curd firmness (CFmax), and of -0.31 with protein recovery in the curd. Differential somatic cell count expressed as proportion was correlated with SCS (0.60) but had only 2 moderate genetic correlations with milk traits: with lactose (-0.32) and CFmax (-0.33). The SCS was highly correlated with the log PMN-LYM count (0.79) and with the log MAC count (0.69). The 2 latter traits were correlated with several milk traits: fat (-0.38 and -0.43 with PMN-LYM and MAC counts, respectively), lactose percentage (-0.40 and -0.46), RCTeq (0.53 and 0.41), tmax (0.38 and 0.48). Log MAC count was correlated with k20 (+0.34), and log PMN-LYM count was correlated with CFmax (-0.26) and weight of water curd as percentage of weight of milk processed (-0.26). The results obtained offer new insights into the relationships between the indicators of udder health and the milk technological traits in Holstein cows.

Evaluation of breeding groups by living weight of over-age cows depending on breeding

The assessment of cattle of black-and-white, red steppe, Simmental breeds, differentiated by live weight, was carried out. Three groups were formed: selection, production, and marriage. The selection parameters are calculated using the standard deviation. The calculated parameters of selection of animals of breeding groups by live weight in full-aged cows of the black-and-white breed are 527–472 kg, red steppe-595–514, Simmental breed from the Novosibirsk region – 555–447, the Republic of Khakassia – 610–475, Hereford – 570–462 kg. The animals of the breeding group of the black-and – white breed have an average live weight of 552.5 kg, the red steppe – 641.1 kg, the Simmental Novosibirsk region – 576.7 kg, the Republic of Khakassia – 648 kg, and the Hereford Region-591.1 kg. The analysis of interbreed differences of cows of breeding groups shows that animals of Simmental and Red steppe breeds surpass their peers in most measurements. Animals of the black-and-white breed are the leaders in milk yield and milk content index, Red steppe-in milk fat content and milk fat, Simmental cows bred in the Republic of Khakassia – in live weight. The assessment of production groups of animals by live weight allows us to note that the black-and-white breed surpasses its peers in milk productivity and is characterized by broadness; the red steppe breed – by live weight and fat content of milk and is characterized by elongation; the Simmental breed has a greater development of high-altitude measurements. Evaluation of breeding groups of animals by live weight allows us to note its relationship with other productive traits. The formation of a breeding group with a high live weight allows you to create a tall and stretched array of cattle.

Технологические особенности производства синбиотического кисломолочного продукта

Introduction. Many strains used in dairy industry are antagonists of harmful microflora. Logically, a successful combination of several cultures can enhance the bactericidal effect. The present research objective was to develop a fermented milk drink using a prebiotic to stimulate a multicomponent starter culture.&#x0D; Study objects and methods. The research featured pure strains of Bifidobacterium bifidum strain No. 791 and Lactobacillus acidophilus (VZ-AP), as well as Bio-fi Pro WR 400 beet fiber. The study involved standard and conventional research methods.&#x0D; Results and discussion. The first stage defined the optimal ratios of B. bifidum and L. acidophilus for a two-component starter culture, as well as the optimal production method and their antibiotic activity. The second stage featured the functional and technological properties of the prebiotic beet fiber and its effect on the development of microorganisms in the starter. The study resulted in the main production parameters and a technological scheme for the production of fermented dairy product.&#x0D; Conclusion. The paper introduces a new technology for production of a functional fermented milk product fortified with probiotics and prebiotics, as well as approved technical documentation. The new functional fermented dairy product was based on a starter&#x0D; culture that combined a liquid concentrate of B. bifidum strain No. 791 and a starter culture of L. acidophilus (VZ-AP). The optimal ratio of microbial cultures was 5:1, respectively. The starter strain proved to have a high antibiotic activity. Prebiotic beet fiber Bio-fi Pro WR 400 could be recommended as a product stabilizer at the optimal amount of 0.7% by weight of standardized milk.

The Deviation between Dairy Cow Metabolizable Energy Requirements and Pasture Supply on a Dairy Farm Using Proximal Hyperspectral Sensing

This study aimed at determining the extent to which the deviation of daily total metabolizable energy (MEt) requirements of individual cows from the metabolizable energy (ME) supplied per cow (DME) varied throughout the production season in a pasture-based dairy farm using proximal hyperspectral sensing (PHS). Herd tests, milk production, herbage and feed allocation data were collected during the 2016–2017 and 2017–2018 production seasons at Dairy 1, Massey University, New Zealand. Herbage ME was determined from canopy reflectance acquired using PHS. Orthogonal polynomials were used to model lactation curves for yields of milk, fat, protein and live weights of cows. Daily dietary ME supplied per cow to the herd and ME requirements of cows were calculated using the Agricultural Food and Research Council (AFRC) energy system of 1993. A linear model including the random effects of breed and cow was used to estimate variance components for DME. Daily herd MEt estimated requirements oscillated between a fifth above or below the ME supplied throughout the production seasons. DME was mostly explained by observations made within a cow rather than between cows or breeds. Having daily estimates of individual cow requirements for MEt in addition to ME dietary supply can potentially contribute to achieving a more precise fit between supply and demand for feed in a pasture-based dairy farm by devising feeding strategies aimed at reducing DME.

Maternal Worry About Infant Weight and its Influence on Artificial Milk Supplementation and Breastfeeding Cessation.

Maternal worry about infant weight has inconsistently been reported as a breastfeeding barrier. Weight monitoring is a critical tool to assess adequacy of infant feeding. Yet, little is known about the intensity of maternal worry about infant weight or associated breastfeeding outcomes. To examine (1) the frequency and intensity of maternal worry about infant weight; (2) the relationship between worry about weight and use of artificial milk; and 3) the relationship between worry about weight and breastfeeding cessation. A prospective cross-sectional design was used. A questionnaire was completed by women in the United States (N = 287) from 12 web-based maternal support groups. Sixty-three percent of women (n = 182) had some worry about infant weight. Participants breastfeeding for the first time had more worry (p = .035). Participants still breastfeeding had less worry about weight compared to those who had stopped (67%, n = 147 vs. 41%, n = 28). Exclusive breastfeeding participants had less worry (p < .001) compared to those who supplemented with artificial milk. Increased worry was associated with the use of artificial milk within 1 week of birth (p < .001) and early breastfeeding cessation (p < .001). Worry about weight is a significant breastfeeding barrier. It is associated with first time breastfeeding, less exclusive breastfeeding, use of artificial milk, and earlier breastfeeding cessation. Lactating mothers need anticipatory guidance about expected neonatal weight changes and interventions to help relieve worry about infant weight.

The possible use of probiotics in the biotechnology of food products

The article represents the results of the research aimed to study the possible use of probiotics in the development of biotechnology for producing soft rennet cheeses with increased biotechnological value. The researchers found that the use of yeast consisting of L. Lactis and B. Subtilis made cheeses ripen faster and achieve the desired values of active and titratable acidity quicker. In control and experimental samples the ripening process took 8 hours while for other rennet cheeses with other probiotic consortiums including L. Lactis it took 12–14 hours to ripe. The addition of B. Subtilis to soft rennet cheese makes cells of probiotic cultures grow faster and more abundantly in comparison to the control sample. However, the microbiological analysis showed that at the end of the ripening process the number of L. Lactis bacteria cells, as well as B. Subtilis in experimental samples was higher than in the control sample by 0.5 and 1.2l g CFU/g respectively. The organoleptic evaluation showed that among seven samples of cheese the sixth sample had the best colour, smell, taste, consistency, pattern, and appearance. The sample had a sweetish cheesy taste, a tender homogeneous plastic consistency, a uniform white colour with holes of irregular, angular, slotlike, and oval forms of 1–2mm. The most rational concentration of Bacillus subtilis (strain 534) bacteria is 5 %. In this case 1ml contains 480 thousand microbial cells. This concentration gives a product a moderately marked cheesy, spicy taste that is inherent to soft cheeses. This indicates the feasibility of using Bacillus subtilis bacteria (strain 534) in the 5 % amount by milk weight.

Cumulative dairy cow genetic change from selection and crossbreeding over the last 2 decades in New Zealand closely aligns to model-based predictions published in 2000

A deterministic model was developed in 1998 to evaluate the concurrent effects of selection and crossbreeding on the rate of genetic gain and increases in productivity of New Zealand dairy cattle over the ensuing 25-yr period. The predictions of today's breed composition of the national dairy herd and genetic trends for body weight and lactation yields of milk, fat, and protein are compared with today's actual values. Selection was assumed to use an index that included live weight and lactation yields of milk, fat, and protein. Mating strategies involving the Holstein-Friesian (F), Jersey (J), and Ayrshire (A) breeds were evaluated. Effects of heterosis and age were included to calculate phenotypic live weight and yields of milk, fat, and protein per cow. At the time the model was developed, New Zealand had an across-breed evaluation system, but only straightbred bulls were used after progeny testing based on records of straightbred and crossbred daughters. The model predicted that if crossbred cows and bulls could be considered as bull parents, faster rates of genetic gain may result because of increased selection intensities in the cow to breed bull selection pathway. This scenario transpired, and the best bulls and cows for farm profit were used regardless of breed. Under that mating strategy for the 2018 birthyear, the model predicted the national breed composition would be 11% F, 34% J, 52% F×J, and 2% A; the actual breed composition was 36% F, 9% J, 53% F×J, and 1% A. The model-predicted annual genetic gains would be 16.7 L of milk, 1.2 kg of fat, 1.5 kg of protein, and −0.7 kg of body weight; the realized annual improvements were 13.6 L of milk, 1.31 kg of fat, 1.17 kg of protein, and −0.36 kg of body weight. Predicted long-term responses to selection can closely mirror realized improvements, confirming the value of modeling to inform animal breeding decision-making.

Alteration of fatty acid profile of milk in Holstein cows fed Bacillus coagulans as probiotic: a field study.

Probiotics may improve milk quality and the general health status of animals. The effects of dietary Bacillus coagulans PRM101 on milk components, milk fatty acids (FA), and some health indicators of dairy cows were investigated. The probiotic was added to the feed of 12 Holstein cows (2 g/cow: 2 × 1011 CFU/cow) for 63 days compared to a control group fed on the basal ration (n=11). Milk and blood samples were taken on days 0, 21, 42, and 63. The yields of milk and energy corrected milk (ECM; computed from milk weight and its fat and protein content) decreased linearly and similarly (P=0.60) in both groups. The treatment cows, however, showed quadratic increases in the weights of milk (P=0.03) and ECM (P=0.04) at d42 of the study. Energy corrected milk (d42, P<0.05) and crude protein content of milk (d42, P<0.05; d63, P<0.1) were higher in the cows receiving the probiotic. The proportions of heptadecanoic (C17:0; P=0.002) and linoleic (C18:2; P=0.077) acids in milk fat (g/100 g fat) were higher in the treatment cows on d63. Milk total antioxidant capacity (TAC), malondialdehyde (MDA), and similarly, amyloid A (AA) and haptoglobin (Hp) of milk and blood were not affected. Total antioxidant capacity and MDA were negatively correlated in the control group (r=-0.669, P=0.005). Heptadecanoic acid correlated negatively with milk MDA (r=-0.611, P=0.035) and positively (r=0.591, P=0.043) with serum Hp in the treatment cows. Dietary B. coagulans PRM101 may improve the proportions of C17:0 and C18:2 FA in milk. Some improvements in milk protein and the health status of the cows may also be anticipated.

Evaluation of Agolin&amp;lt;sup&amp;gt;&amp;amp;reg&amp;lt;/sup&amp;gt;, an Essential Oil Blend, as a Feed Additive for High Producing Cows

There is a growing demand for feed additives that can not only reduce dairy enteric methane emissions but also increase milk production and feed efficiency. Just one product is currently commercially available which accomplishes both of these goals. The purpose of this study was to confirm the performance benefits of the product (Agolin?, Agolin SA, Biere, Switzerland) in high producing mid-lactation dairy cows under United States feeding conditions. Four matched pens of approximately 150 mid-lactation cows/pen and averaging over 50 kg of milk/cow/day were enrolled in a side-by-side study. All pens received a common total mixed diet ad libitum, and the essential oil blend was administered via a concentrated farm pack to provide 1 g/cow/day to cows in the 2 test pens. Milk weights were determined, and samples were collected for compositional analysis over the last 2 days of the pretrial (May 11 and 12, 2020) and end of the trial (July 18 and 19, 2020) periods. Dry matter intake was measured by pen daily for the last 10 days of each feeding period. Milk fat and milk protein yields were greater (P 0.05) for cows receiving added Agolin. There was a tendency (P = 0.06) for energy corrected milk/dry matter intake to be greater for cows receiving the Agolin (1.88) relative to the control diet (1.76). The trial showed that Agolin assisted in improving production parameters of economic importance to dairy producers.

Effects of supplementary feeding lucerne hay and barley grain to Angora does during the last third of pregnancy and lactation, and of litter size on pasture, birth weight, live weight, parasitism, milk production, milk composition and mohair production

The effects of feeding lucerne hay (Medicago sativa) and or barley grain to grazing reproducing Angora does on birth weight, live weight, body condition, quality and production of milk and mohair and gastrointestinal parasitism were investigated in does and kids. The design was supplementation for the last 8 weeks prepartum to 8 weeks postpartum with 5 levels of whole barley grain (GL: 0, 115, 230, 345, 460 g/d/doe) × 2 levels of hay supplementation (HL, 380 g/d/doe 8 weeks prepartum, 0 g/d postpartum; HH, 830 g/d/doe 8 weeks prepartum, 800 g/d/doe 8 weeks postpartum) × 2 randomised blocks. This provided 20 experimental plots, 10 for each level of hay and 4 for each GL. Each plot contained one dry doe, three single litter does, and one twin litter doe. Pastoral conditions were poor with low availability of green pasture until late spring. Does kidded in early August. Important results were: GL affected kid live weight, milk production, composition and secretion of milk solids, total mohair production and some mohair quality measures but GL increased fibre diameter and incidence of medullated fibres in kid mohair; optimum performance at day 40 of lactation was GL 345 which produced 2325 g/d milk corrected to 4% fat. HH increased secretion of milk protein and total solids compared with HL. Twin litters had greater persistence in lactation to day 100 of lactation compared with single litters. There was evidence that high levels of barley feeding reduced faecal egg count. Dry does gained more live weight, grew 26 % more mohair which was 1.7 μm coarser compared with does with single litter. The results indicate that feeding lucerne hay even under adverse seasonal conditions was of little value. The lactation performance of these grazing Angora does was substantially less than their potential. Optimum barley feeding was GL 345 g/d/doe. There was evidence of substitution of pasture for hay. The results quantified the production responses and penalties of Angora does when litter size was increased from non-pregnant status (zero) to 2.

КОНЦЕПЦИЯ СОЗДАНИЯ ЦИФРОВОЙ СИСТЕМЫ УПРАВЛЕНИЯ ПРОЦЕССОМ НОРМИРОВАННОЙ ВЫДАЧИ КОНЦЕНТРИРОВАННЫХ КОРМОВ ЖИВОТНЫМ

Currently used systems for normalized distribution of concentrated feed to animals based on volumetric dispensers have a number of disadvantages that reduce their functionality and efficiency of practical use. (Research purpose) The research purpose is in developing the concept and main components of a digital control system for the process of normalized distribution of concentrated animal feed with automatic weight portion dosing of individual doses. (Materials and methods) The article proposes the concept of a system for managing the process of normalized distribution of concentrated animal feed, which consists in automatic calculation of individual feed doses taking into account the weight of animals, monitoring productivity, lactation periods, milk and feed quality, and generating digital data corresponding to the calculated doses. (Results and discussion) The article presents the concept of building a digital system for managing the processes of normalized distribution of concentrated animal feed. The article presents its structure and technological scheme. Author developed functional and schematic diagrams of the basic components: a code converter to an analog pneumatic signal, a system for addressing pneumatic signals, a device for comparing moments of forces; algorithms for the functioning of the system and its unified basic components. (Conclusions) The automatic concentrate feeding system allows for more accurate and balanced feeding of each animal. The portion, weight normalized distribution of concentrated feed to animals according to the schedules established by the zootechnical services of enterprises contributes to the development of their genetic potential and the preservation of animal health. The power supply and control signals of individual mechatronic, weight, and portion dispensers have a single physical nature and level, which simplifies and increases the reliability of the “Ration” system.

Longitudinal study on the effects of intramammary infection with non-aureus staphylococci on udder health and milk production in dairy heifers

We conducted a longitudinal study to evaluate the effect of non-aureus staphylococci (NAS) causing subclinical intramammary infections (IMI) on quarter milk somatic cell count (qSCC) and quarter milk yield (qMY). In total, 324 quarters of 82 Holstein Friesian heifers were followed from calving to 130 d in milk (DIM) and were sampled 10 times each at 14-d intervals. The IMI status of each quarter was determined based on bacterial culture results at the current and previous or next sampling day, or both. The qSCC was determined on each sampling day and the average qMY on sampling day was available through stored daily milk weight data in the management program of the automatic milking system. A transient IMI (tIMI) was defined as a case where a specific pathogen was isolated from a quarter on only one sampling day and not on the previous or next sampling day. When the same bacterial strain, as defined by random amplification of polymorphic DNA-PCR, was isolated from the same quarter on multiple sampling days, it was defined as a persistent IMI (pIMI) status on those sampling days; a pIMI episode was defined as the combination of multiple consecutive pIMI statuses with the same bacterial strain on different sampling days. During this study, 142 subclinical IMI with NAS occurred in 116 different quarters from 64 animals, yielding in total 304 NAS isolates belonging to 17 different species. The prevalence of NAS was highest in the first 4 DIM. Overall, the predominant species was Staphylococcus chromogenes (52% of the isolates), followed by S. epidermidis (9.2%), S. xylosus (8.2%), and S. equorum (5.9%). Staphylococcus chromogenes was the only species for which an effect on qSCC and qMY could be analyzed separately; the other NAS species were considered as a group because of their low prevalence. Eighteen out of 40 IMI (45%) caused by S. chromogenes persisted over at least 2 sampling days, whereas only 10 of 102 (9.8%) IMI caused by other NAS species persisted for at least 2 sampling days. The average duration of pIMI episodes was 110.4 d for S. chromogenes and 70 d for the other NAS species. Remarkably, 17 of the 18 pIMI episodes with S. chromogenes started within the first 18 DIM. The qSCC was highest in quarters having a pIMI with a major pathogen, followed by quarters having a pIMI with S. chromogenes, and a pIMI with other NAS. Transient IMI with other NAS or with a major pathogen caused a small but significantly higher qSCC, whereas the qSCC in quarters having a tIMI with S. chromogenes was not statistically different compared with noninfected quarters. No significant differences in qMY were observed between quarters having a pIMI or tIMI with S. chromogenes or with the other NAS species compared with noninfected quarters, despite the higher qSCC. Quarters having a pIMI with major pathogens showed significantly lower daily milk production. Surprisingly, quarters that cured from an IMI with S. chromogenes had a significantly lower qMY than noninfected quarters.

Investigation of dairy cow performance in different udder health groups defined based on a combination of somatic cell count and differential somatic cell count

Mastitis is still the costliest disease in milk production. In particular, its subclinical form, which may spread unnoticeably within a herd, is a major challenge. Somatic cell count (SCC) is broadly used as an indicator for mastitis and thus the basis for udder health management programmes, e.g. through dairy herd improvement (DHI) testing. Since recently, differential somatic cell count (DSCC, representing the combined proportion of polymorphonuclear neutrophils and lymphocytes as a percentage of total SCC) is available in addition. Our study was aimed to investigate dairy cow performance in four newly defined udder health groups (UHG) based on SCC and DSCC results from DHI testing. In total, 961,835 test-day results generated in Austria, China, Estonia, Germany, and Spain between January 2019 and March 2020 were available for data analyses. Cows were categorised into four UHG depending on test day SCC and DSCC results (UHG A: healthy/normal, ≤200,000 cells/mL and ≤65 %; B: suspicious, ≤200,000 cells/mL and >65 %; C: mastitis, >200,000 cells/mL and >65 %; D: chronic/persistent mastitis, >200,000 cells/mL and ≤65 %). Linear mixed effect models were used to compare the performance of cows between the UHG based on the parameters milk weight, energy-corrected milk, fat, protein, lactose, and estimated milk value. Highest performance was found for cows in UHG A and ranged between 21.4 (Austria) and 38.3 kg per cow and day (Spain). Interestingly, cows in group B were significantly less productive (0.9–2.4% less daily milk production) compared to those in group A. Cows in groups C (6.0–9.8% less daily production compared to group A) and D were, as expected, even less productive with a particularly significant drop for cows in group D (17.5–38.5% less daily production). These trends could be observed in all countries involved in this study. Proportions of cows in the four different UHG differed between countries, changed slightly within countries depending on season, differed depending on parity and days in milk, and were seen to vary hugely between herds. In conclusion, this study demonstrates changes in performance of dairy cows depending on their udder health status as defined based on the combination of SCC and DSCC. In particular cows in UHG B and D are of interest as they cannot be identified working with SCC only. Nevertheless, the actual udder health management measures that could be taken based on the new UHG still require further investigation.

Evaluation of the new differential somatic cell count parameter as a rapid and inexpensive supplementary tool for udder health management through regular milk recording

Mastitis, particularly in its subclinical form, is the costliest disease in milk production causing substantial financial losses to the dairy industry, impairing animal welfare, and one of the main reasons for treating dairy cows with antimicrobials. Somatic cell count (SCC) is broadly used as an indicator for mastitis or intramammary infection (IMI) and is the basis for udder health management programmes, e.g., through monthly dairy herd improvement (DHI) testing. While SCC shows the total number of cells in milk, the new Differential SCC (DSCC) shows also the combined proportion of polymorphonuclear neutrophils (PMN) and lymphocytes as a percentage of the total SCC. In this study, we investigated the test characteristics of DSCC as a new supplementary indicator for mastitis screening. We collaborated with 11 herds totalling 969 dairy cows and collected metered DHI samples once a month over four months. The IMI status was assessed through analysis of aseptic composite hand-stripped samples using culture and followed by species identification using MALDI-ToF. The pathogens detected were categorised as ‘no’, ‘minor’, ‘major’, or ‘other’ pathogens. The results of our study showed that the DSCC parameter was significantly associated with the IMI status and the cow’s parity but not with days in milk or test-day milk weight. On the other hand, SCC was associated with all these four factors. DSCC counts were significantly higher in samples of cows with IMI caused by major pathogens as compared to cows with no IMI or IMI by minor or other pathogens. SCC alone, DSCC alone, and the combination of DSCC and SCC were further compared based on test characteristics using exemplary cut-offs. For example, working with a cut-off of 200,000 cells/ for SCC alone compared to working with the combination of DSCC of 65 % and/or 200,000 cells/mL to classify cows as infected by major pathogens, the sensitivity increased from 78 % to 92 % and the specificity decreased from 87 % to 66 %. With the combination, the positive predictive value changed from 52 % to 34 %, and the negative predictive value stayed at the same level (96 % vs 98 %). In summary, our study provides first insights on test characteristics of the DSCC parameter used in combination with the well-established SCC for monitoring udder health using DHI testing. This combination opens up the possibility to further improve udder health monitoring programmes (e.g., improved identification of IMI caused by major pathogens) but more work on the subject is needed.

Modeling the Process of Heat Treatment of Liquid Products in a Plate Heat Exchanger Using an Integrated Energy-Substituting Installation

Introduction. Currently, the issue of reducing electrical energy consumption in the technologies of processing agricultural products, in particular, milk is topical. In large part, these costs are associated with the implementation of heat treatment processes. The reduction of electrical energy consumption can be achieved in several ways, one of which is the development and application of solar-powered installations. In this case, the consumption of traditional electrical energy is significantly reduced, but the manufactures have the task of coordinating the installation parameters and the real production conditions of enterprises. Materials and Methods. The study examined energy consumption in milk processing technologies, plate heat exchanger operation modes and heliocollector performance indicators. The heating temperature of the coolant and the product was determined with an instrument complex that allows registering the temperature values in 8 different control points and transmitting the received signals to the personal computer hard disk. The method for defining the parameters of the plant for preparing the coolant in the technologies of milk processing with the use of a complex energy-substituting unit is proposed. The new technique provides a reduction of electric energy consumption from 30 to 70%. Results. The consumption of electrical energy for thermal processes can be reduced by using solar energy. To solve the problem of optimizing the ratio of product consumption, heating area in the heat exchanger, the area of the solar collectors of the energy-substituting installation, it is recommended to use the obtained graphical dependencies and the formula for determining the area of the solar collectors. Discussion and Conclusion. It is possible to determinate the area of solar collectors of complex energy-substituting installation for real production conditions through using the obtained analytical dependence taking into account the dependence the specified parameter on a temperature mode of heating, the area of a surface of heating in the heat exchanger, and weight of milk being processed per unit of time. The obtained graphical dependencies make it possible to determine the product consumption and heating area for the given heating temperature values.

Evaluation of cervical and uterine size, at 4weeks postpartum, as a predictor of subsequent fertility in Jersey cattle.

Uterine and cervical size of Holstein dairy cows is reported among reasons for a decline in dairy cow fertility. Therefore, the objectives of this study were to (a) determine whether size of the cervix and uterus at 4weeks postpartum impacted subsequent fertility at first service in Jersey cattle, (b) determine whether progesterone level at 4weeks postpartum impacted cyclicity and (c) the association of the presence of corpus luteum and uterus and cervix size. Body condition scores at calving, presence of postpartum diseases, parity number and milk weights were taken from lactating Jersey dairy cows (N=147) for 28days postpartum. During the fourth week postpartum, a blood sample was obtained for progesterone concentration, and transrectal ultrasonography was performed by a high-resolution ultrasound machine to determine cervical and uterine horn diameter, as well as ovarian structures measurements. Correcting for parity number, BCS at calving, presence of diseases and milk yield, cows with a cervix >2.54±0.63cm and uterine horn >2.25±0.59cm were less likely to become pregnant at first service (p=.04 and p=.003, respectively). The cows with larger cervix had a trend to be less likely to have a corpus luteum present at the 4th week of lactation (p=.067). Cows with larger uterine horn size were less likely to have a corpus luteum present at the 4th week of lactation (p=.015). It is concluded that a larger cervix and/or uterus during the postpartum was associated negatively with fertility and cyclicity in Jersey cows.

Modeling weight loss of cheese during ripening and the influence of dairy system, parity, stage of lactation, and composition of processed milk

The yield, flavor, and texture of ripened cheese result from numerous interrelated microbiological, biochemical, and physical reactions that take place during ripening. The aims of the present study were to propose a 2-compartment first-order kinetic model of cheese weight loss over the ripening period; to test the variation in new informative phenotypes describing this process; and to assess the effects on these traits of dairy farming system, individual farms within dairy system, animal factors, and milk composition. A total of 1,211 model cheeses were produced in the laboratory using individual 1.5-L milk samples from Brown Swiss cows reared on 83 farms located in Trento Province. During ripening (60 d; temperature 15°C, relative humidity 85%), the weight of all model cheeses was measured, and cheese yield (cheese weight/processed milk weight, %CY) was calculated at 7 intervals from cheese-making (0, 1, 7, 14, 28, 42, and 60 d). Using these measures, a 2-compartment first-order kinetic model (3-parameter equation) was developed for modeling %CY during the ripening period, as follows: [Formula: see text] , where %CYt is the %CY at ripening time t; %CYi and %CYf are the modeled %CY traits at time 0 d (%CYi = initial %CY) and at the end of a ripening period sufficient to reach a constant wheel weight (%CYf = final %CY after 60 d ripening in the case of small model cheeses); kCY is the instant rate constant for cheese weight loss (%/d). Cheese weight and protein and fat losses were calculated as the % difference between the model cheeses at 0 and after 60 d of ripening. The variation in cheese pH was calculated as the % difference between pH at 0 and after 60 d. Dairy system, individual herd within dairy system, and the cow's parity and lactation stage (tested with a linear mixed model) strongly affected almost all the traits collected during model cheese ripening. Milk fat, protein, lactose, pH, and somatic cell score also greatly affected almost all the traits, although kCY was affected only by milk protein. After including milk composition in the linear mixed model, the importance of all the herd and animal sources of variation was greatly reduced for all traits. The proposed model and novel traits could be tested, first, with the aim of establishing new monitoring procedures enabling the dairy industry to improve milk quality-based payment systems at the herd level and, second, with a view to exploring possible genetic improvements to dairy cow populations.