Journal of Dairy Science最新文献

{"title":"Influence of feeding systems on the microbial community and flavor characteristics of raw milk: A comparative analysis","authors":"Yang Yang ,&nbsp;Xiaoyan Wu ,&nbsp;Yanwei Xu ,&nbsp;Quan Shuang ,&nbsp;Ya Nan Xia","doi":"10.3168/jds.2024-25959","DOIUrl":"10.3168/jds.2024-25959","url":null,"abstract":"<div><div>This study analyzed the composition of the microbial community in raw milk and its effects on flavor compounds by comparing samples from cows raised on pasture (PXN) and in housing (HXN). In August 2023, 9 raw milk samples from Holstein cows were collected from a pasture in the Xilin Gol League, Inner Mongolia, China, and labeled as the PXN group. Simultaneously, 9 raw milk samples were collected from Holstein cows raised by individual farmers in the region and labeled as the HXN group. Metagenomic sequencing technology was used to detect and analyze the dynamics of microbial community in milk samples. At the same time, headspace solid-phase microextraction, electronic nose, and electronic tongue technology were used to monitor the flavor characteristics of raw milk under the 2 feeding conditions and to analyze the correlations between them. The results showed that raw milk protein (PXN, 3.43%; HXN, 3.36%) and fat (PXN, 4.01%; HXN, 3.79%) content in pasture group were higher than that in the housed group, and lactose content (PXN, 4.98%; HXN, 5.12%) and total solid content (PXN, 4.98%; HXN, 5.12%) were lower than that under the housed system. However, there was no significant difference between nonmilk fat solid contents of the 2 groups. The W1C, W5C, W5S, and W2S sensors of the electronic nose played an important role in distinguishing the 2 groups of samples. The sour taste of raw milk in the pasture group was different from that of the in-house feeding group. There were significant differences in the microbial communities of the 2 groups, with <em>Macrococcus caseolyticus</em> (39.85%) in the PXN group and <em>Lactococcus lactis</em> (49.59%) in the HXN group being the dominant bacteria. The volatile compounds of raw milk in the PXN and HXN groups were detected by a headspace solid-phase microextraction method. A total of 62 and 53 flavor compounds were detected in the PXN and HXN groups, respectively. Terpenoids, esters, and aldehydes were dominant in the PXN group, and acids were dominant in the HXN group. The saturated fatty acid content in the HXN group (76.13%) was higher than that in the PXN group (72.47%). The CLA content in the PXN group (3.56 g/100 g) was higher than that in the HXN group (1.32 g/100 g). The dominant strains, that is, <em>Macrococcus caseolyticus</em>, <em>Lactococcus lactis</em>, and <em>Lactococcus cremoris</em>, in both PXN and HXN groups exhibited positive effects on the formation of alcohols, esters, phenols and unsaturated fatty acids. In addition, <em>Macrococcus caseolyticus</em> in the PXN group showed significant positive correlation with calcium lactate. This study comprehensively describes the microbial community structure and flavor quality of raw milk under different feeding methods, which may serve as a reference to control the quality of raw milk.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 4693-4708"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The relationship between milk urea nitrogen content and urinary nitrogen excretion as determined in 4 Swiss dairy breeds","authors":"A. Burren ,&nbsp;M. Terranova ,&nbsp;M. Kreuzer ,&nbsp;T. Kupper ,&nbsp;S. Probst","doi":"10.3168/jds.2024-25915","DOIUrl":"10.3168/jds.2024-25915","url":null,"abstract":"<div><div>Ammonia (NH₃) originating from agriculture substantially contributes to the environmental nitrogen load and threatens sensitive ecosystems by inducing eutrophication and acidification of the soil. To strategically minimize NH₃ emissions, this study aimed to develop a model to predict urinary nitrogen (UN) excretion (g/d), the major NH₃ source of cows of different dairy breeds, based on an easy-to-determine proxy as an on-farm tool. For that purpose, dietary characteristics were not considered. One such proxy would be the MUN content, which could be determined in tank milk samples from dairy farms. We therefore investigated the UN and MUN values from 21 different feeding experiments performed in Switzerland with 4 contrasting dairy breeds. These were 162 Brown Swiss (BS), 348 Holstein (HO), 44 Jersey (JE), and 50 Swiss Fleckvieh (SF) cows. We investigated the relationship between the coefficients of the UN and MUN using various linear mixed models. The forward model selection demonstrated that it is essential to consider the interaction between MUN and breed, as well as BW and breed, when modeling UN. Furthermore, there was a pronounced heteroscedasticity between UN and MUN for higher MUN values (&gt;14 mg/dL). This heteroscedasticity must be accounted for, either through explicit modeling or log transformation. The final model included fixed effects, MUN, BW, and breed, the interactions, MUN × breed and BW × breed, as well as the experiment as random effect. This model also considered the heteroscedasticity. In the final model, R² was high, at 81.2%. The regression coefficients and highest posterior density intervals were 7.28 (5.42; 9.02), 10.41 (9.16; 11.65), 9.00 (6.20; 11.94) and 11.79 (9.15; 14.25) g/d of increase in UN per mg/dL of MUN for BS, HO, JE, and SF, respectively. The estimated regression coefficients for BW and highest posterior density intervals were 0.09 (−0.01; 0.19), 0.17 (0.11; 0.27), 0.51 (0.21; 0.80) and 0.28 (0.03; 0.53) for BS, HO, JE, and SF, respectively. The estimated marginal means ± SE for UN (g/d) were 117 ± 12, 147 ± 12, 119 ± 14, and 135 ± 14 for BS, HO, JE, and SF, respectively. These results confirm MUN content to be a useful tool to predict UN excretion in lactating dairy cows, as suggested by previous studies. However, in contrast to previous findings, our results underscore the necessity of accounting for breed and BW in the predictive model. The established model improves the accuracy of mass flow models that estimate NH₃ emissions based on the UN excretion of livestock at the beginning of the manure management chain.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 5342-5360"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptation strategies to manage summer forage shortages improve animal performance and better maintain milk and cheese quality in grass- versus corn-based dairy systems","authors":"M. Bouchon ,&nbsp;B. Martin ,&nbsp;C. Bord ,&nbsp;A. Ferlay ,&nbsp;J.M.G. Bloor ,&nbsp;M. Eugène ,&nbsp;A. Delacroix-Buchet ,&nbsp;C. Cebo ,&nbsp;M.C. Michalski ,&nbsp;B. Graulet ,&nbsp;I. Verdier-Metz ,&nbsp;C. Delbès","doi":"10.3168/jds.2024-25730","DOIUrl":"10.3168/jds.2024-25730","url":null,"abstract":"<div><div>In semi-mountainous grass-based dairy systems, summer droughts frequently reduce grass availability, with implications for animal performance as well as milk and cheese quality. The objective of our study was to investigate the effect of a simulated summer forage shortage in a traditional semi-mountainous grass-based system versus a corn-based system with part-time grazing. During a 19-wk experiment, 26 Prim'Holstein and 14 Montbéliarde cows were blocked in 4 balanced groups of 10 cows. During the first 8 wk, 2 groups were fed a grass-based diet (75% of grazed grass, 25% of hay and concentrates) and the remainder were fed a corn-based diet (75% mixed ration, 25% of grazed grass). During the following 11 wk, one group in each feeding system was subjected to a reduction in grazed grass intake and a corresponding increase in indoor feeding, resulting in 50% of grazed grass for grass-fed cows and removal of grazed grass for corn-fed cows. Milk yield and composition were recorded during the whole trial, in addition to indoor individual intake. Grass intake was modeled to calculate feed efficiency and estimate methane emissions. At the end of the experiment, bulk milk from each group was sampled for physicochemical and microbiological analyses and processed into Cantal-type cheeses. After 9 wk of ripening, cheeses underwent physicochemical, microbiological and descriptive sensory analyses. Results showed that the complete removal of grazed grass in corn-based system had no effect on milk production but impaired feed efficiency; grass reduction in the grass-based diet better maintained milk yield, enhanced feed efficiency, and reduced methane emission intensity. Cheese softness increased with proportion of grass in the diet, and it was positively correlated with primary proteolysis (α_S1-casein and β-casein breakdown) but negatively correlated with the C16:0/C18:1 ratio and the calculated fat melting point. Cheese from cows fed with more grazed grass were the yellowest and had the most pronounced flavors, as well as higher counts of heterofermentative lactobacilli and lactic acid bacteria. Removal of grazed grass from the corn-based diet led to cheese that was less yellow and had less flavor, in line with lower levels of secondary proteolysis. In conclusion, our study suggests that maintaining fresh herbage in corn-based diets is crucial for maintaining cheese quality without impairing animal performance. In grass-based systems, complementation with indoor feeding may have limited effects on product quality but promotes the maintenance of animal performance.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 4796-4817"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dairy farm management factors associated with clinical observations in young dairy calves sold at auction markets in Québec, Canada: A cross-sectional study","authors":"Sébastien Buczinski ,&nbsp;Gilles Fecteau ,&nbsp;Anne-Sophie Perrault ,&nbsp;Salvatore Ferraro ,&nbsp;Julie Arsenault ,&nbsp;Younes Chorfi ,&nbsp;Marcio Costa ,&nbsp;Jocelyn Dubuc ,&nbsp;David Francoz ,&nbsp;Marjolaine Rousseau ,&nbsp;Marianne Villettaz-Robichaud","doi":"10.3168/jds.2024-26118","DOIUrl":"10.3168/jds.2024-26118","url":null,"abstract":"&lt;div&gt;&lt;div&gt;In Québec, Canada, nonreplacement calves are generally sent at a young age to auction markets to be sold for veal or dairy beef production. Various clinical observations found during the calves' journey, either at an auction market or on arrival at a calf raiser farm, have been associated with increased risk of morbidity, such as dehydration or umbilical problems. The objective of this cross-sectional study was to quantify associations between calf raising management strategies at the dairy farm level and clinical observations at auction markets during sale. For this purpose, during 8 different sale days, the 2 largest auction markets in Québec were visited, and all calves sold on those days were systematically examined. The number of clinically relevant findings (CRF) present per calf (among presence of umbilical cord, wet umbilical area, umbilical pain, umbilical swelling, persistent cervical skin fold ≥2 s, sunken eyes, eye or nasal discharge, ear drop, limb anomaly, emaciation or dirty hide) was recorded. After the sale, farm owners were contacted to answer a specific questionnaire on calf management. The total number of CRF from all sold calves from the same farm (dependent variable) was modeled using Poisson multivariable regression, with questionnaire answers as potential covariates and the number of calves sold per farm during the observation period as an offset. The questionnaire was completed during a standardized phone call and focused on farm characteristics and characteristics of calves sold, including calving management, calf care at birth, nutrition, housing, and transportation. A total of 3,656 calves from 1,349 different sellers were examined. The questionnaire information was obtained from 409 different farms representing 847 calves. The median number of calves sold per farm was 2 (range: 1–19). The umbilical cord was visually present in 376 calves (44%). Among the most commonly observed CRF, eye discharge (n = 290, 34%), umbilical swelling (n = 144, 17%), and presence of dehydration signs (persistent cervical skin fold ≥2 s [n = 111, 13%] or sunken eyes [n = 83, 9.8%]) were the most commonly reported anomalies. According to the final multivariable Poisson regression model, the incidence rate ratio (IRR) of CRF for farms that sold calves at a mean age &lt;8 d was higher than for farms that sold calves at a mean age of &gt;10 d (IRR = 1.21, 95% CI: 1.04–1.41). The IRR was also higher for farms that did not give colostrum to calves within 1 h following birth compared with calves receiving colostrum within 1 to 2 h (IRR = 1.73, 95% CI: 1.24–2.49), 2 to 6 h (IRR = 1.48, 95% CI: 1.06–2.14) and more than 6 h (IRR = 1.59, 95% CI: 1.06–2.44) after birth. The IRR were higher for farms using milk replacer to feeding sold calves versus raw milk (IRR = 1.2, 95% CI: 1.06–1.37) and higher for farms where calves typically receive their last meal &gt;3 h before transportation to the auction market versus calves receiving their last me","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 5170-5181"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of preweaning milk allowance on long-term metabolism in Holstein heifers","authors":"L.N. Leal ,&nbsp;J.B. Daniel ,&nbsp;J. Doelman ,&nbsp;B.R. Keppler ,&nbsp;M.A. Steele ,&nbsp;J. Martín-Tereso","doi":"10.3168/jds.2024-26005","DOIUrl":"10.3168/jds.2024-26005","url":null,"abstract":"<div><div>Suboptimal preweaning nutrition of dairy calves has been causally associated with impaired adult metabolic health and lactation performance. However, the biological mechanisms linking early life nutrient supply and future performance remain insufficiently understood. Thus, the objective of this study was to characterize growth, reproductive performance, glucose metabolism, and the metabolic profile of growing heifers fed a restricted (RES) or an elevated (ELE) milk supply preweaning. Heifer calves (n = 86) born from a single herd of ∼120 dairy cows were blocked in pairs by the dam's parity and birth date. Within block, calves were fed an identical colostrum supply and randomly assigned to a milk replacer (MR) allowance level treatment of either 5.41 Mcal of ME in 8 L of MR/d (ELE) or 2.71 Mcal of ME in 4 L of MR/d (RES). The MR (150 g/L), containing 24% crude protein, 18% crude fat, and 45% lactose, was fed from d 2 after birth until calves were stepped down by 50% at d 49 and fully weaned at d 56. All calves were kept in individual hutches until wk 10 and had ad libitum access to fresh pelleted calf starter, chopped wheat straw, and water. Starting from wk 8, heifers from both treatments were fed and managed in the same way, and preweaning treatments were blind to caretakers. Blood samples for metabolomics analysis were collected at 330 d of age, and an insulin-modified intravenous glucose tolerance test was conducted at 370 ± 12 d of age. Heifers fed the ELE diet exhibited higher average daily gain in the preweaning period, leading to higher body weight at 70 d of age (+ 9 kg). At 330 d of age, growth advantages were no longer significant, and preweaning nutrition had no effect on age at first service, first service conception rates, age at conception, or number of services per conception. The metabolomic serum data sampled at 330 d of age revealed that carnitine, glycerolipid, and purine metabolism were predicted to be significantly affected by preweaning nutrient supply, reflecting long-term metabolic programming. At 370 d of age, during the first 20 min following the glucose infusion, blood insulin levels were greater (10.3 ng/mL vs. 7.7 ng/mL), the area under the curve for insulin tended to be greater, and insulin sensitivity was lower in RES heifers. Increasing the amount of MR fed to calves preweaning had a sustained impact on metabolic processes, but long-term differences could not be detected in growth or reproductive performance, potentially due to the low number of animals.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 4988-4999"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143727228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A focus group study exploring necessary competencies and contextual factors for effective antimicrobial stewardship on dairy farms","authors":"Devon J. Wilson ,&nbsp;Elizabeth M. Parker ,&nbsp;Rafael Portillo-Gonzalez ,&nbsp;Pamela L. Ruegg ,&nbsp;Gregory G. Habing","doi":"10.3168/jds.2024-25302","DOIUrl":"10.3168/jds.2024-25302","url":null,"abstract":"<div><div>There is a need for improved antimicrobial stewardship on dairy farms, and changes will be largely enacted by the farm workers who are responsible for carrying out farm procedures. For this reason, efforts directed at educating and enabling farm workers in antimicrobial stewardship are necessary for compliance with farm-level antimicrobial usage policies. Therefore, the objectives of this research were (1) to determine the competencies needed by dairy farm workers to implement antimicrobial stewardship and to inform educational resource development and (2) explore the farm contexts that influence farm worker antimicrobial stewardship capabilities. Initially, focus group discussions were conducted in person with 6 groups of veterinarians at 3 independent conferences held in the United States. To gain additional perspectives, 2 focus groups were conducted via video link with dairy producers from the midwestern United States. The focus groups had 4 to 8 participants and 2 to 4 facilitators each, and were audio recorded and transcribed for analysis. Discussions were audio recorded, transcribed, and evaluated using inductive thematic analysis, with 9 key themes identified. Participants emphasized that farm workers needed to be willing to learn, to be responsible, and to be consistent in their execution of tasks. Furthermore, farm workers needed knowledge about the rationale behind antimicrobial use strategies and disease mitigation practices. General skills needed by farm workers included good communication, excellent observation, and the ability to follow protocols and keep records. Technical skills required by farm workers related to the handling of animals, attention to cleanliness, ability to properly administer pharmaceutical products, and farm equipment maintenance. The skills and knowledge required differed among farm workers depending on their responsibilities and experience, with greater expectations for herd managers compared with employees who specialized in a specific task such as milking. Farm contexts that affected antimicrobial stewardship included the farm size, which had an impact on the 3 other themes: workplace culture, leadership, and tools. Workplace culture encompassed having an approachable environment and clear responsibilities, and leadership encompassed managerial capacity and veterinary support. Important tools for effective antimicrobial stewardship included relevant and up-to-date protocols, technology, equipment, and a proficient workforce. The evidence provided through these focus groups is useful for informing competency-based educational efforts aimed at improving antimicrobial stewardship on dairy farms.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 5182-5192"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565653","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Use of termination events and mortality data recorded during the lactation as a proxy to predict the genetics of resilience and health of dairy cattle","authors":"M. Haile-Mariam ,&nbsp;M.E. Goddard ,&nbsp;Joanna Newton ,&nbsp;Michelle Axford ,&nbsp;Gert Nieuwhof ,&nbsp;M. Khansefid","doi":"10.3168/jds.2024-25812","DOIUrl":"10.3168/jds.2024-25812","url":null,"abstract":"<div><div>Increasing production and environmental challenges in dairy cattle means that selecting for resilience is becoming more important. This study explored whether data on cows that exit before completing their lactation and those that die during lactation can be used to predict resilience. To identify predictors of resilience, exiting the herd by 60, 120, 180, and 240 d were defined as traits. Additional traits were defined by including all the cows that died during the entire lactation with the cows that exited at different times up to 240 d of lactation. For all traits, cows that exited the herd or died were coded as 1, otherwise as 0, at the end of the lactation. We used performance and exit data of Holstein (HOL) and Jersey (JER) cows that calved between 1998 and 2023. The data were analyzed using a multitrait sire model to estimate heritability and correlations with milk yield (MY), SCC, calving interval (CIN), and selected type traits. The results showed that the proportion of cows that exited by 60 d was 2%, increasing by about 2% every 2 mo until exit by 240 d. The trend over the years in the proportion of exits, taking exit by 180 d and exit by 180 d + death as an example, showed an undesirable increase from 5.6% in 2000 to 9.4% in 2022. Heritability of all exit traits was low, increasing from below 1% for exit by 60 d to 2.8% for exit by 240 d + all deaths over the lactation. The genetic correlation of early exit (i.e., 60 or 120 d) with first test-day MY was positive (unfavorable) and higher at the beginning (0.4), decreasing over time to be favorable in JER (−0.2) and near zero in HOL (0.1) by the end of the lactation. In contrast, the genetic correlation of exit with first test-day SCC became stronger (favorable) at the end of the lactation (0.3 to 0.4). Exit at any time during the lactation had the strongest genetic correlation with CIN (i.e., fertility). The genetic correlation of exit traits with BCS and angularity showed that the likelihood of cow exit, especially up to 180 d, was higher for thin and more angular cows. The genetic correlation estimates imply that cows with high potential for MY, poor fertility, poor BCS, and high scores for angularity are more likely to exit early due to metabolic stress. The change in genetic correlation between exit and MY early from unfavorable to favorable in JER due to more culling for milk and less for fertility and udder health is leading to an undesirable genetic trend for exit by 180 d as well as exit by 180 d + all death. However, the increasing phenotypic trend of exit rates in both breeds suggests a need for close monitoring. The selective use of exit data can help to develop genetic evaluations for resilience and health traits and validate and complement data collected to improve health and welfare during the transition period.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 5076-5091"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143073135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Immunoglobulin G absorption dynamics in neonatal calves: An investigation of the effects of casein presence in colostrum","authors":"E.V. Lopez-Bondarchuk ,&nbsp;J.M.V. Pereira ,&nbsp;G. Mazon ,&nbsp;J.V.R. Lovatti ,&nbsp;A.J. Geiger ,&nbsp;J.H.C. Costa","doi":"10.3168/jds.2024-25785","DOIUrl":"10.3168/jds.2024-25785","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Casein presence in colostrum may affect the absorption of immunoglobulins in neonate dairy calves. This randomized controlled trial investigated the effect of casein presence in colostrum replacer on serum IgG dynamics on calves. Seventy-one calves (BW: 45.3 ± 5.9 kg) were randomly assigned to 1 of 3 colostrum treatments: colostrum replacer with casein addition to match the maternal colostrum (CR+C; n = 23; 85 g/L of IgG; Premolac Plus, Zinpro; 95 g/L of casein); colostrum replacer without casein addition (CR-C; n = 23; 85 g/L of IgG; Premolac Plus, Zinpro); and maternal colostrum (MC; n = 25; 85 g/L of IgG). Dystocia scores were recorded, and 3 h after birth, calves received 3.7 L of solution via tube feeding. Blood samples and calf vigor assessments were conducted at colostrum feeding (0 h) and 6, 12, 18, 24, 36, 48, and 72 h after colostrum feeding. Serum was analyzed for IgG concentration (g/L) and serum total protein (g/dL; STP). In addition, apparent efficiency of absorption of IgG (%; AEA), maximum IgG concentration (g/L; Cmax), time to maximum IgG concentration (h; Tmax), IgG area under the curve (g/L × h; AUC), and the apparent IgG persistency (%; AIP) were calculated. An ordinal logistic model was used to evaluate the odds of treatment improving a calf's vigor category from colostrum feeding (3 h of age) to 72 h after colostrum feeding. Vigor score was categorized as abnormal (≤4), average (5), or alert (≥6), with hour as a fixed effect. Mixed linear models were used to evaluate the effect of colostrum treatments on serum IgG, STP, AEA, Cmax, Tmax, AIP, and AUC, with time, dystocia score, calf sex, BW, and a treatment by time interaction as fixed effects. Calf vigor scores were not influenced by colostrum treatments. Treatment and time interaction affected serum IgG and STP levels after colostrum feeding. Serum IgG was lower for CR with casein addition (CR+C- compared with CR-C-treated calves) from 6 to 72 h. No difference was observed for serum IgG between CR+C- and MC-treated calves, regardless of time. Additionally, treatment affected AEA, with CR+C-treated calves exhibiting reduced AEA compared with CR-C calves (CR-C = 36.7 ± 2.0%, CR+C = 27.4 ± 2.1%, MC = 31.3 ± 2.1%). Treatment affected the Cmax, with CR+C-treated calves exhibiting reduced Cmax compared with CR-C and MC calves (CR-C = 29.5 ± 1.3 g/L, CR+C = 21.1 ± 1.3 g/L, MC = 26.2 ± 1.4 g/L). No differences were observed between treatments for Tmax and AIP. The AUC was lower for CR+C- compared with CR-C- and MC-treated calves (CR-C = 2,641.2 ± 117.5 g/L × h, CR+C = 1,719.3 ± 120.6 g/L × h, MC = 2,197.5 ± 124.4 g/L × h). For STP, no differences were observed between CR+C- and CR-C-treated calves (from 6 to 72 h). However, calves fed CR+C and CR-C displayed lower STP levels compared with MC-treated calves (from 12 to 24 h). These findings suggest that casein presence in colostrum replacer influences calf serum IgG concentration, STP levels, and AEA in neonatal calves.&lt;/d","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 5209-5217"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143727239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Time to presumptive conceptus attachment and subsequent pregnancy loss in pasture-based lactating dairy cows following artificial insemination with conventional or X-sorted semen or embryo transfer","authors":"A.D. Crowe ,&nbsp;J.M. Sánchez ,&nbsp;S.G. Moore ,&nbsp;M. McDonald ,&nbsp;F. Randi ,&nbsp;A. Santos ,&nbsp;T. Minela ,&nbsp;J. Branen ,&nbsp;J. Furlong ,&nbsp;J.R. Pursley ,&nbsp;P. Lonergan ,&nbsp;S.T. Butler","doi":"10.3168/jds.2024-25725","DOIUrl":"10.3168/jds.2024-25725","url":null,"abstract":"<div><div>The objective of this study was to determine the effect of the timing of presumptive conceptus attachment (pCA) and its relationship with subsequent pregnancy loss (PL) in lactating dairy cows following timed artificial insemination with conventional (TAI-C) or X-sorted (TAI-S) semen or timed embryo transfer (TET) with frozen-thawed in vitro–produced (IVP) embryos. Lactating cows (n = 417, predominantly Holstein-Friesian) located in 3 herds were blocked based on parity, calving date, and economic breeding index and randomly assigned to receive TAI-C (n = 136), TAI-S (n = 136) or TET with a single, grade-1 frozen-thawed IVP blastocyst (n = 145). Cows were synchronized with a 10-d Progesterone-Ovsynch protocol, and were either inseminated (TAI-C, TAI-S) 16 h after the second GnRH or received TET on d 7 after presumptive estrus. Serum progesterone was measured in all cows on d 7 after expected ovulation. For all cows that had not returned to estrus, serum pregnancy-specific protein B (PSPB) was measured on d 7, 17, and daily from d 19 through 28 after expected ovulation to characterize the timing of pCA. The day of pCA was defined as the first day of an increase in PSPB of ≥12.5% from baseline (d 17) followed by 2 more consecutive days of ≥12.5% increase from the previous day. Pregnancy was diagnosed in cows that had not returned to estrus via ultrasound examination on d 32, 62, and 120 postovulation, and calving data were recorded. Day of pCA (mean; 95% CI) was earlier for TAI-C (20.0; 19.7, 20.3) compared with TET (20.6; 20.3, 20.9), and TAI-S (20.3; 19.9, 20.6) was not different from the other 2 treatments. Calving/service event (C/SE) was greater (83.2% vs. 54.4%) and PL during the interval from pCA to expected calving date was less (16.8% vs. 45.6%) for cows with early pCA (≤d 20; 23/137) compared with cows that had late pCA (≥d 21; 36/79). The incidence of PL was greater for cows assigned to TAI-S (30.7%) and TET (33.8%) than TAI-C (16.4%). Consistent with previous studies, measuring time to pCA provides new insights into understanding early pregnancy establishment and PL in lactating dairy cows. The timing of pCA was later for TET compared with TAI-C and may be associated with increased risk of PL. Further research into the regulatory mechanisms underlying conceptus attachment is warranted.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 5420-5432"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Changes in microbial community structure during adaptation of kombucha symbiotic culture of bacteria and yeast to fermentation of sweet and acid whey","authors":"Alyssa Thibodeau ,&nbsp;Patrick Reardon ,&nbsp;Bjarne Bartlett ,&nbsp;Christopher Curtin","doi":"10.3168/jds.2024-25859","DOIUrl":"10.3168/jds.2024-25859","url":null,"abstract":"<div><div>Whey is a liquid byproduct from the dairy industry that is not fully utilized and can be problematic to dispose of. Based on its composition, there is potential to upcycle whey into fermented beverages for human consumption. Most focus to date has been upon alcoholic fermentation to generate alcohol for distillation, or use of kefir grains to make acidic beverages. Kombucha fermentation is analogous to kefir, with a solid-state inoculum that is backslopped from one batch to the next, but yields a different profile of organic acids when applied to its typical substrate of tea sweetened with sucrose. Notably, some kombucha symbiotic cultures of bacteria and yeast (SCOBY) harbor a lactose-fermenting yeast species, <em>Brettanomyces anomalus</em>, rendering it possible that a SCOBY system could be adapted to lactose-containing whey substrates. The objective of this research was to apply a <em>B. anomalus</em>-containing kombucha SCOBY to the fermentation of sweet and acid whey. Sequential batch fermentations were performed to determine changes in microbial community structure and fermentation outcomes during adaptation to whey substrates. Metabarcoding targeting the fungal ITS2 region and the bacterial 16S V4–V5 domain was used to assess fungal and bacterial communities, respectively. We used ¹H nuclear magnetic resonance to determine the chemical composition of fermentations. The <em>B. anomalus</em>-containing kombucha SCOBY was able to perform repeat backslop-inoculated whey fermentation, with the major fermentation products being those characteristic to kombucha fermentation (acetic acid and ethanol). The whey-adapted SCOBY was characterized by replacement of the original main fungal taxa, <em>Brettanomyces bruxellensis</em>, by the lactose-fermenting <em>B. anomalus</em>, whereas the bacterial community remained more diverse.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 5","pages":"Pages 4761-4784"},"PeriodicalIF":3.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}