Journal of Dairy Science最新文献

{"title":"Dutch bovine viral diarrhea virus control program: Evaluation 2018–2023","authors":"E.E.C. Strous ,&nbsp;P.I.H. Bisschop ,&nbsp;G. van Schaik ,&nbsp;M.H. Mars ,&nbsp;H.W.F. Waldeck ,&nbsp;C.G.M. Scherpenzeel ,&nbsp;B. de Roo ,&nbsp;P. Wever ,&nbsp;I.M.G.A. Santman-Berends","doi":"10.3168/jds.2024-25798","DOIUrl":"10.3168/jds.2024-25798","url":null,"abstract":"<div><div>Since 2018, Dutch dairy farmers have been obliged to opt for 1 of 4 routes to achieve bovine viral diarrhea virus (BVDV) freedom in the national BVDV eradication program. This observational study evaluated efficacy of the total BVDV program using indicators such as the number of persistently infected (PI) cattle, the percentage of dairy herds with a BVDV-free status, and the percentage of BVDV-free dairy herds with evidence of introduction of BVDV, as well as a cost calculation per route. The Dutch BVDV program appeared to be successful, as the percentage of BVDV-free dairy herds increased from 59% at the start of the program to 89% by the end of 2023. The number of PI detected each quarter declined from 500 PI in the third quarter of 2019 to 83 PI in the last quarter of 2023. The percentage BVDV-free dairy herds with evidence of (re)introduction of BVDV decreased from 1.29% per quarter in the first year of the mandatory program to 0.25% per quarter by the end of 2023. In Europe, BVDV control program designs are often tailored to the country's specific situation, such as the prevalence at the start of eradication, risk profile of a country or herd, desired speed of eradication, and available funds. These results show that the Dutch approach, in which multiple routes can be followed toward BVDV freedom, is successful.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2780-2794"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142862671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of different doses of 3-nitrooxypropanol combined with varying forage composition on feed intake, methane emission, and milk production in dairy cows","authors":"Morten Maigaard ,&nbsp;Martin R. Weisbjerg ,&nbsp;Christer Ohlsson ,&nbsp;Nicola Walker ,&nbsp;Peter Lund","doi":"10.3168/jds.2024-25343","DOIUrl":"10.3168/jds.2024-25343","url":null,"abstract":"<div><div>The objective of this study was to investigate the effect of combining different doses of 3-nitrooxypropanol (3-NOP) with varying forage composition on gas emission and production performance of dairy cows. Seventy-two lactating Danish Holstein cows (36 primiparous and 36 multiparous) were enrolled in a continuous randomized block design with an initial 2-wk covariate period followed by application of treatments for 12 consecutive weeks. Initial DMI and ECM yield were 23.8 ± 3.34 kg/d (mean ± SD) and 38.3 ± 7.12 kg/d, respectively. Cows were blocked according to parity and DIM. Treatments were organized in a 2 × 3 factorial arrangement. The first factor was diet type, reflecting 2 different forage compositions of the diet. The ratio of grass-clover silage to corn silage was 60%:40% of total forage DM in grass-based diets and 40%:60% in corn-based diets. In total, forage constituted 56% of the DM in the partial mixed rations. The second factor reflected 3 doses of 3-NOP: 0, 60, or 80 mg 3-NOP/kg DM. Gas emissions were measured using GreenFeed systems and feed intake by using Insentec Roughage Intake Control bins. Weekly averages from the last 10 wk were analyzed by using a mixed model including fixed effects and interactions among diet type, 3-NOP dose, week, and parity, and included a covariate term and accounted for repeated measures. Methane yield (g/kg DMI) was reduced by 34% and 31%, and CH₄ intensity (g/kg ECM) was reduced by 34% and 32% at 60 and 80 mg 3-NOP/kg DM, respectively, and we found no difference in CH₄ yield or intensity between the 2 doses. The corn- and grass-based diets were similar in NDF and starch levels, and we found no interaction between dose of 3-NOP and diet type for CH₄ yield or intensity. Total DMI was reduced by 9% in cows fed 80 mg 3-NOP/kg DM across diet types, whereas we found no effect on DMI at 60 mg 3-NOP/kg DM. Similarly, ECM yield was reduced by 5% in cows fed 80 mg 3-NOP/kg DM compared with no 3-NOP supplementation, and these cows had a 42% lower BW increase over the experiment compared with no supplementation. In conclusion, 3-NOP at 60 mg/kg DM was efficient in reducing CH₄ without compromising feed intake and milk production, whereas 80 mg 3-NOP/kg DM negatively affected production performance.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2489-2502"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142862673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"United States dairy farms and global warming","authors":"C. Alan Rotz ,&nbsp;Frank Mitloehner","doi":"10.3168/jds.2024-25360","DOIUrl":"10.3168/jds.2024-25360","url":null,"abstract":"<div><div>Several metrics have been developed for combining the warming effects of various GHG. The metric used can affect the life cycle assessment and comparison of dairy production systems due to the weighting placed on long- versus short-lived gases in the atmosphere. Global warming potential (GWP) with a time horizon of 100 years (GWP-100) has become the standard, but metrics are also available for other time horizons. Metrics for 20-, 100-, and 500-year horizons gave average farm-gate emission intensities of 2.08, 0.98, and 0.50 kg of CO₂ equivalents per kilogram of fat- and protein-corrected milk produced for current US dairy farms. Compared with the use of GWP metrics, which represent energy absorption, use of global temperature change potential (GTP), combined global temperature change potential (CGTP), or global warming potential star (GWP*) reduced the warming effect of methane relative to other GHG. These metrics representing temperature change reduced the warming potential of US dairy farms by 17% to 49% compared with the use of GWP-100. The metrics used also affected the comparison of individual production systems, providing different life cycle assessments of management practices. Use of GWP-100 metrics indicated that warming from GHG emissions of US dairy farms increased 11 % to 15% between 1971 and 2020, whereas the use of GTP, CGTP, and GWP* metrics showed little or no effect on global temperature change over the 50-year period. Use of GWP-100 metrics indicated that GHG emissions related to milk production on dairy farms represented 1.6% of all US GHG emissions in 2020 whereas use of other metrics ranged from 0.9% to 1.8%. Although all approaches for representing the integrated warming impact of GHG have benefits and challenges, approaches such as CGTP and GWP*, which account for the rate of methane emission relative to the oxidation rate in the atmosphere, provide a more process-based assessment of the long-term impact of dairy farms on global temperature and perhaps offer a more scientifically sound approach for assessing strategies to mitigate the warming effect of dairy farms.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2610-2619"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142862676","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Food labeling and Chinese consumer preference for naturalness: A new way to differentiate grass-fed dairy products","authors":"Jingjing Wang ,&nbsp;Chenguang Li ,&nbsp;Xiaoxia Dong ,&nbsp;Zhifeng Gao ,&nbsp;Eileen R. Gibney ,&nbsp;Shuhua Yang ,&nbsp;Lauren McGuinness ,&nbsp;Nessa Noronha ,&nbsp;Emma L. Feeney","doi":"10.3168/jds.2024-25576","DOIUrl":"10.3168/jds.2024-25576","url":null,"abstract":"<div><div>Due to the lack of recognized differentiation for grass-fed dairy products, producers of quality products have failed to capture consumer premiums. This study investigates Chinese consumers' preferences for the naturalness attributes of grass-fed dairy products as potential criteria for grass-fed milk product differentiation. We examine how grazing conditions (e.g., pasture grazing), animal feed (e.g., fed grass), functional improvement (e.g., increasing CLA, n-3, and vitamin B content), and imagery properties (healthy, natural, tasty, and sustainable) affect consumers' preferences and willingness to pay. Interestingly, consumers reported higher premiums for grazing conditions, animal feed, and functional improvements compared with imagery property attributes. Contrary to the conventional belief that functional improvement attracts the highest consumer premium, we found that for the majority of respondents (who have high preference for naturalness), grazing conditions were the most important factor. This study provides evidence for consumer preferences for the subattributes of grass-fed products, and therefore develops a potential framework to differentiate grass-fed products using naturalness criteria.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2340-2353"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142875711","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Grape pomace supplementation reduced methane emissions and improved milk quality in lactating dairy cows","authors":"A. Akter ,&nbsp;X. Li ,&nbsp;E. Grey ,&nbsp;S.C. Wang ,&nbsp;E. Kebreab","doi":"10.3168/jds.2024-25419","DOIUrl":"10.3168/jds.2024-25419","url":null,"abstract":"<div><div>Grape pomace (GP) is a byproduct of the viticulture industry and shows promise for feeding dairy cattle as well as reducing enteric methane (CH₄) emissions. This study investigates the potential of using fresh GP in dairy cow feeding and its effects on CH₄ emissions. Multiparous Holstein dairy cows (n = 24, 205 ± 39 DIM) were housed in freestall barns and provided rations consisting of alfalfa hay, wheat hay, almond hulls, cottonseed, and grain mix. After a 2-wk adaptation period, cows were randomly assigned to one of the 3 treatments: a control diet (CON), a diet with 10% grape pomace (10% GP), and a diet with 15% GP (15% GP) on a DM basis. Treatments were arranged in a 3 × 3 Latin square design, where cows received 3 treatments over 3 periods, each period lasting for 4 wk. Rations were provided twice daily and gas emissions from cows were measured using an automated GreenFeed system. Milk production was recorded both in the morning and evening, and milk samples were collected weekly for fat, protein, lactose, SNF, MUN, and SCC analysis. For fatty acids analysis, milk samples were collected on the last 3 d of each 28-d period. Data were checked for normality and were analyzed using a mixed model ANOVA in proc GLIMMIX in SAS. Dry matter intake was reduced in GP-fed cows, where CON had the highest DMI followed by 10% and 15% GP. Methane and H₂ emissions were reduced in GP-supplemented group compared with CON group. On the other hand, CO₂ emissions was found higher in the GP-supplemented groups compared with the CON group. Milk yield was not different among different GP treatments. Although no differences were observed in fat, protein, lactose, SNF, and SCC, we did observe that MUN was lower in the 10% and 15% GP groups compared with the CON group. The reduction in CH₄ emissions in the GP-supplemented groups suggests that the chemical components of GP were effective in reducing CH₄ emissions. In contrast, the lower DMI in GP-supplemented groups indicates that DMI can act as an indicator of lower CH₄ production. No effects on fat, protein percentage, and milk yield indicated that GP did not negatively affect milk production. Total PUFA and linoleic acid in milk fat were greater in 10% and 15% GP groups compared with the CON group. In conclusion, GP supplementation helped reduce enteric CH₄ emissions from cows without affecting milk production.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2468-2480"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142875712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic associations of colostrum yield with antibody concentrations and gross composition for selective breeding in Italian Holsteins","authors":"Arianna Goi ,&nbsp;Angela Costa ,&nbsp;Mauro Penasa ,&nbsp;Martino Cassandro ,&nbsp;Maurizio Marusi ,&nbsp;Raffaella Finocchiaro ,&nbsp;Massimo De Marchi","doi":"10.3168/jds.2024-25527","DOIUrl":"10.3168/jds.2024-25527","url":null,"abstract":"<div><div>The quality of bovine colostrum (BC), primarily determined by the concentration of IgG, is essential for the transfer of passive immunity and the development of the gastrointestinal tract in neonates. High IgG concentration in BC is pivotal for the calf at the first meal, but neonates often refuse to voluntarily drink the recommended amount in the first hours of life, and dams frequently fail to produce a sufficient volume of colostrum at first milking. This study seeks to estimate the h² of colostrum yield (CY) and its genetic correlations with total Ig and IgG, protein, and fat concentrations for the first time in the Italian Holstein population. Colostral Ig concentration and gross composition were assessed on individual samples collected using ad hoc near-infrared spectroscopy prediction models. The infrared-predicted traits, along with the measured CY, were used as phenotypes (n = 2,938) for the estimation of genetic parameters through linear animal models. Parity, photoperiod at calving, and classes of CY significantly altered colostral composition, with parity having the most important influence. Colostrum of older cows, in fact, had greater total Ig, IgG, and protein concentrations than colostrum of younger cows. Colostral quality and CY were higher when calvings occurred in months with decreasing photoperiod. Also, CY was maximum in second-parity cows. Heritability estimates of IgG and total Ig concentrations were 0.225 ± 0.05 and 0.211 ± 0.05, approximately twice the h² estimate for CY (0.101 ± 0.03). The correlation between CY and IgG concentration was positive (0.219 ± 0.032) at the phenotypic level and negative at the genetic level (−0.147 ± 0.190). Spearman rank correlations between EBV of the colostrum traits and official EBV and indexes, for which selection is ongoing in the Italian Holstein breed, were generally weak or moderate and not always significant. Specifically, CY was unfavorably associated with the PFT (production, functionality, and type; −0.300) and the IES (economic health; −0.335) indexes, and IgG concentration was favorably linked to the official indexes for udder health/mastitis resistance (0.154) and fertility (0.166), mirroring those calculated for total Ig. Selection toward an intermediate optimum for CY at calving can be potentially pursued in the Italian Holstein breed through a balanced index without incurring additional costs for IgG concentration.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2697-2709"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Invited review: Recent developments in understanding the rehydration characteristics of high-protein dairy powders","authors":"S. Roy,&nbsp;J.K. Amamcharla","doi":"10.3168/jds.2024-25699","DOIUrl":"10.3168/jds.2024-25699","url":null,"abstract":"<div><div>The use of dairy-based ingredients is increasingly prominent in the food industry due to their functional and nutritional benefits. High-protein powders are highly attractive due to their superior nutritional (e.g., high protein, calcium) and functional benefits (e.g., gelation, emulsification, foaming). Complete rehydration is essential for achieving optimum functionalities. However, poor wettability, slower rehydration, and the presence of insoluble particles are observed in high-protein dairy powders, especially in casein-rich powders, such as milk protein concentrate and micellar casein concentrate. The low solubility of these powders can cause processing difficulties, such as clogged filters and processing lines, leading to a loss of nutritional and functional properties and increased operating costs. Therefore, it is crucial to measure rehydration characteristics before application. Characterizing the different phases of rehydration helps in identifying the rate-limiting stages and strategies to improve them. Various methods for measuring each rehydration stage are discussed in detail in this review. Methods based on changes in conductivity, turbidity, particle size, and rheological properties during powder reconstitution are examined. Various imaging techniques, ultrasound-based methods, and nuclear magnetic resonance techniques that have been used for characterizing rehydration behavior are also expanded upon here. Apart from these techniques, the methods suitable for in-line application in the industry are also mentioned. In addition to dairy powders, the rehydration of infant formula is discussed. The rehydration of infant formula is important for ease of end-user application and for delivering proper nutritional values. This review discusses common methods such as the insolubility index and wetting time, as well as some newer techniques based on focused beam reflectance measurement, electric resistance tomography, and Lumisizer. Overall, this review elucidates the existing industrial methods and recently developed techniques for characterizing rehydration, their applicability for in-line measurement, and their advantages and disadvantages.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2133-2151"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"When to pair: Effects of different pairing ages on dairy calf health, behavior, and performance","authors":"M.S. Moroz ,&nbsp;C.C. Martin ,&nbsp;J.H.C. Costa ,&nbsp;R.R. Daros","doi":"10.3168/jds.2024-25686","DOIUrl":"10.3168/jds.2024-25686","url":null,"abstract":"<div><div>Pair housing presents an alternative to individual or larger group housing systems, though the effects of different pairing ages on calf welfare are not well understood. In this study, we examined the effect of pairing age on the performance, health, and behavior of dairy calves. A total of 140 Holstein female calves (n = 70 pairs) were used, paired at 3 stages: early (6–7 d; 48 calves), intermediate (29–30 d; 48 calves), and late (49–50 d; 44 calves). Calves were housed individually before pairing and weaned at 78 ± 2 d of age. Weight measurements were recorded at birth, 30, 50, and 60 d, and at weaning. Calves' behavior was assessed 5 times per week through scan sampling after milk feedings from d 6 to 7 until weaning, and a food neophobia test was conducted at 50 to 51 d. Health assessments were performed 3 times per week by a veterinarian using Wisconsin clinical scores to diagnose diarrhea and bovine respiratory disease, with pulmonary ultrasonography at 55 d. The results suggest no association between pairing age and the prevalence of diarrhea or bovine respiratory disease, although the statistical power was limited. The number of calves with lung consolidation scores above 2 was also unaffected by pairing age. Early-paired calves exhibited more exploration and play behaviors and less idleness, stereotypies, and nonnutritive oral behaviors than late-paired calves. No differences were observed in cross-suckling likelihood across pairing ages. Early-paired calves also showed a shorter latency to touch a novel feed in the food neophobia test, higher calf starter intake during the first 15 d, and greater ADG up to 50 d. Although overall ADG did not differ among pairing ages, early-paired calves were more homogeneous in weaning weight than late-paired calves. In conclusion, early pairing supports calves' initial development, promoting early feeding behavior and growth and enhancing behaviors associated with positive affective states without adverse effects on health or undesirable behaviors.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2839-2855"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942164","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Milk feeding and calf housing practices on British Columbia dairy farms","authors":"Elizabeth R. Russell,&nbsp;Marina A.G. von Keyserlingk,&nbsp;Daniel M. Weary","doi":"10.3168/jds.2024-25561","DOIUrl":"10.3168/jds.2024-25561","url":null,"abstract":"<div><div>Decades of research have helped inform practices on how to care for calves, but little is known about how well these practices are adopted on commercial dairy farms. The primary aim of this study was to describe rearing practices of dairy calves in British Columbia, Canada. Measures of calf growth are sometimes used to assess success in calf rearing, so a secondary aim was to describe methods used to assess calf growth on these farms. All 437 dairy farms in the province were invited to participate in a survey distributed via email from the British Columbia Ministry of Agriculture and Food from June to December 2023. A total of 63 completed responses were received (i.e., 14.4% of those invited). Milking herd size averaged (± SD) 167 ± 172 cows, and the primary breed was Holstein for 84.1% of respondents. Most (63.5%) farms housed calves individually before weaning; the remainder used either just social housing (groups of 2 or more; 25.4% of farms) or a combination of individual and social housing (11.1% of farms). Maximum milk allowance averaged 9.5 ± 2.7 L/d, with 86.4% of respondents offering &gt;8 L/d. Teat feeding was used on 71.6% of farms, and 13.1% of farms used automated milk feeders. Two participants reported feeding calves via the dam or nurse cows. Weaning age averaged 75.8 ± 16.3 d, with calf age being the primary criterion for weaning. About half (52.4%) of farms reported monitoring calf growth, and 31.7% of farms reported having a target growth rate. Our results suggest that rearing practices are changing, in that calves are now often fed higher milk rations via a teat, and many farms use social housing. However, individual housing remains prevalent, suggesting research is needed to understand the barriers to adopting social housing on farms. Our findings also suggest the opportunity to improve methods for monitoring calf growth; improved measures may facilitate evidence-based evaluations of calf rearing and weaning protocols on farms.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2875-2882"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In-laboratory inactivation of H5N1 in raw whole milk through milk acidification: Results from a pilot study","authors":"Beate M. Crossley ,&nbsp;Craig C. Miramontes ,&nbsp;Daniel Rejmanek ,&nbsp;Rodrigo Gallardo ,&nbsp;Richard Pereira","doi":"10.3168/jds.2024-25985","DOIUrl":"10.3168/jds.2024-25985","url":null,"abstract":"<div><div>Avian Influenza virus H5N1 2.3.4.4.b has recently been detected in cattle, with milk from infected animals reported to contain a high viral load, serving as a potential source for shedding and dissemination of this virus. Currently, pasteurization is the only widely recognized method for on-farm inactivation of H5N1 in milk. A current concern is that according to <span><span>USDA</span></span> data, less than 50% of large dairy farms pasteurize nonsaleable milk, with a much lower percentage occurring in medium and small dairy farms. The objective of this pilot study was to evaluate the effect of milk acidification to a pH of ∼4.0 to 4.4 and lactoperoxidase system (LP system) on the inactivation of low pathogenic avian influenza (LPAI) and highly pathogenic avian influenza (HPAI) in raw whole milk. Initial trials in our study used the LPAI H6N2 virus as a surrogate for HPAI H5N1. For the acidification trials, citric acid was used to acidify milk. For evaluation of milk acidification and LP system, milk samples were inoculated with LPAI H6N2, with samples collected before and after treatment at various times. Evaluation of virus viability was conducted using specific-pathogen-free embryonated chicken eggs and viral quantification using real-time quantitative PCR. Three acidification experiments were conducted using milk spiked with LPAI H6N2. Given the positive outcome observed in the inactivation of LPAI with citric acid, a fourth trial was conducted with milk containing a high load of H5N1 originating from actively infected cows. Our results indicated that milk acidification with a pH between 4.1 and 4.2 resulted in the inactivation of LPAI H6N2 and HPAI H5N1 virus in milk after 6 h of treatment. Milk treatment with the LP system was not effective for the inactivation of the H6N2 virus, and no further trials were conducted for this treatment option. This is the first study reporting the effectiveness of milk acidification for the inactivation of HPAI H5N1 in milk originating from animals infected with H5N1. Milk acidification is an effective, accessible, and easy-to-use alternative to milk pasteurization, and future studies should evaluate the on-farm effectiveness of acidification of nonsaleable milk to inactivate H5N1.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 3","pages":"Pages 2264-2275"},"PeriodicalIF":3.7,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143073225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}