JOURNAL OF DAIRY SCIENCE乳品科学杂志
JOURNAL OF DAIRY SCIENCE(英文缩写 J DAIRY SCI),ISSN 0022-0302,eISSN 1525-3198,中文译名:乳品科学杂志 是一本学术期刊。本页汇总该期刊的最新影响因子、分区信息以及最新收录于 PubMed 的文献,帮助您快速了解期刊全貌。
发文量统计区间：2025-11-01 至 2026-10-31，按本站收录文献的发表日期统计。
期刊介绍
历年影响因子趋势
| JCR 数据年份 | 影响因子 | JCR 分区 |
|---|---|---|
| 2021 | 4.225 | Q1 |
| 2022 | 3.500 | Q1 |
| 2023 | 3.700 | Q1 |
| 2024 | 4.400 | Q1 |
| 2025 | 4.700 | Q1 |
JOURNAL OF DAIRY SCIENCE 最新收录文献
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1. Effects of phytogenic supplementation at different dietary protein concentrations on performance, rumen fermentation, and nutrient digestibility in lactating dairy diets.
PMID:日期:2026-09-21We aimed to evaluate the effects of phytogenic supplementation at different dietary protein concentrations in lactating dairy cattle diets. We hypothesized that phytogenic supplementation with a blend of several plant-based ingredients providing saponins, encapsulated cinnamaldehyde, curcumin, capsaicin, and piperine would act synergistically with dietary protein supply to maintain or enhance lactational performance when CP is adequate. Twenty-four lactating Holstein dairy cows were used in a 4 × 4 Latin Square design with 4 28-d experimental periods (21 d adaptation + 7 d collection) and 4 treatments in a 2 × 2 factorial arrangement (CP concentrations and phytogenic supplementation): 16.5% without or with phytogenic and reduced CP concentration at 14.5% without or with phytogenic supplementation. Phytogenic supplement was top-dressed (7 g/d) on the TMR. Intake and milk yield were recorded daily, and milk samples were collected during the last week of the experimental period for milk components and FA analysis. Data were analyzed using PROC GLIMMIX of SAS 9.4 and the statistical model included the main effects of protein, phytogenic supplement and their interaction and period as a fixed effect, and cow nested in square as a random effect. Significance was declared at P ≤ 0.05 and tendencies were discussed at 0.05 <P ≤ 0.10. Milk yield (MY) and feed efficiency (MY/DMI) were greater with adequate protein diets whereas phytogenic supplementation had no main effect on these variables; however, DMI increased with phytogenic supplementation in reduced CP diets. Phytogenic supplementation increased milk fat concentration and yield, 3.5% FCM, ECM, and the proportions of de novo and preformed FA, while mixed FA tended to increase. In summary, phytogenic supplementation, irrespective of dietary CP concentration, enhanced FCM, milk fat concentration and yield, as well as the proportion of de novo and preformed FA. Additionally, adequate protein diets, regardless of phytogenic supplementation, increased milk yield and improved feed efficiency.
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2. Stakeholder perspectives on dairy calf management challenges in North America.
2. 利益相关者对北美奶牛犊牛管理挑战的看法PMID:日期:2026-09-21Calf morbidity is common on dairies, yet stakeholders who troubleshoot these challenges possess critical experiential knowledge regarding which practices to prioritize during outbreaks. This study evaluated calf experts' perceptions of management practices most critical to address when dairies experience a high prevalence of diarrhea (>25%), bovine respiratory disease (BRD; > 15%), and umbilical infections (>5%) in calves up to 90 d of age. An online survey used a snowball sampling strategy to recruit North American calf experts (n = 70; veterinarians, extension professionals, nutritionists, and consultants) who had no financial stake in a dairy and had troubleshot calf health on ≥3 commercial farms within the past year. Respondents scored the relevance of 8 management domains from 0 to 100; domains scoring > 80 triggered "drill-down" questions where experts ranked specific management failures. Garrett scores assessed consensus within rankings, with scores > 60 indicating important factors and ≥70 indicating strong consensus. Overall, 51% (36/70) of experts reported working with farms experiencing high BRD, followed by diarrhea (47%; 33/70) and umbilical infection (13%; 9/70). For BRD, calf housing/environment had the greatest mean relevancy, followed by colostrum management and nutrition. Strong consensus emerged that restricted nutrition, specifically feeding a low quantity of milk solids (≤0.5 kg/d or ≤4 L/d), is a pivotal management failure to address during BRD outbreaks (Garrett Score = 74.75). Other critical BRD contributors included inadequate colostrum volume (≤2 L; Garrett Score = 67.94), large social groups (>10 calves; Garrett Score = 62.05), and poor winter ventilation (<4 air exchanges/h; Garrett Score = 61.60). For diarrhea, sanitation had the highest perceived relevancy, followed by colostrum, housing, and nutrition. Experts demonstrated near-consensus that large social groups (Garrett Score = 68.90) and low milk solids (Garrett Score = 68.90) exacerbate diarrhea challenges, alongside a lack of sanitation standard operating procedures (SOPs; Garrett Score = 64.36) and low colostrum volume (Garrett Score = 64.00). For umbilical infections, clear consensus linked outbreaks to a lack of umbilical cord dipping (Garrett Score = 73.60), with poor maternity pen hygiene as another contributor (Garrett Score = 68.80). These findings uniquely highlight that experts view nutritional restriction and protocol gaps as central drivers of disease severity. This study identified that dairy stakeholders such as veterinarians, extension/academics, consultants, and nutritionists believe that calf disease challenges on farm are linked to a lack of standard operating procedures for sanitation, colostrum and umbilical cord care. Moreover, underfeeding calves at ≤4 L/d milk, and housing more than 10 calves in a pen was perceived as being related to high disease pressure herds struggling with neonatal calf diarrhea and bovine respiratory disease. This suggests that future North American research should move beyond isolated risk factors to investigate how group-housing dynamics and formalization of management (such as SOP implementation) interact to influence calf disease resilience.
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3. Characterizing dairy cows based on their daily behavior deviation patterns relative to the herd using a clustering approach.
3. 基于奶牛相对于牛群的日常行为偏差模式，利用聚类方法对奶牛进行特征分析PMID:日期:2026-09-21Large variability in the behavioral patterns among individual cows has been reported in previous studies, which compromises the interpretation of herd behavioral patterns. Assessing the behavioral variability of cows at the subgroup level may make the interpretation clearer. The aims of the current study were (1) to assess the individual behavioral variability among cows by clustering individuals based on deviations from herd level patterns in lying duration, number of steps, and number of posture changes at the daily level and during specific time periods within a day, separately for periods without and with pasture access, and (2) to characterize the identified clusters according to their behavioral variables and parity. Accelerometer data, including lying duration, number of steps, and posture changes in 15-min intervals of 185 individual cows in the year 2019, were retrieved from one commercial dairy farm in the Netherlands. From the behavioral data, 13 variables describing the behavioral deviation from the herd level in lying duration, number of steps, and posture changes were extracted per individual cow, including absolute deviation across a day and signed deviation in specific time periods within a day. K-means clustering based on the extracted variables was performed to cluster individual cows in periods without pasture access and with pasture access separately. In both clustering analyses, the same 4 types of individual cow clusters were identified. The behavioral deviation patterns of the 4 types of clusters were further characterized based on the mean values of variables of individual cows per cluster: 1) locomotive; 2) standing; 3) restless; 4) lying. Cows in the locomotive cluster had shorter lying duration and higher number of steps than the herd level. Cows in the standing cluster had shorter lying duration, lower number of steps, and fewer posture changes than the herd level. Cows in the restless type cluster had higher lying duration, number of steps, and more posture changes than the herd level. Cows in the lying cluster had higher lying duration and lower number of steps than the herd level. 72.4% of the individual cows were consistently clustered in the same type of cluster, independent of whether cows were on pasture or not. The majority of cows in parity 1 were clustered in the locomotive type of clusters. Most cows in parity 2 were clustered in the standing type of clusters, whereas most cows in parity 3 or greater (parity 3) were clustered in the lying type of clusters. In conclusion, 4 distinct types of behavioral deviation patterns were observed among individual cows via a clustering approach and were generally consistent in periods without and with pasture access. In general, the cows in parity 2 and parity 3 had lower number of steps and posture changes than cows in parity 1. This study demonstrates the potential to use clustering to improve interpretation of individual behavioral variability and patterns.
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4. Indoor-housed dairy heifers' motivation to access an additional space.
4. 舍饲条件下的奶牛后备牛获取额外空间的动机PMID:日期:2026-09-21Dairy heifers are often housed in confined environments that can limit the range of behaviors they express. Previous studies have assessed the motivation of indoor-housed dairy cows for specific resources, such as pasture or brushes, by comparing the weight animals are willing to push to access these resources relative to an empty space. However, little is known about how much confined cattle value access to additional space itself. We assessed the use of, and motivation to access, additional space in dairy heifers housed in a freestall barn. Holstein heifers (n = 48; mean age: 7.1 ± 0.74 mo; mean BW: 279.8 ± 32.57 kg) were housed in 4 groups of 12 in pens (7 m x 12 m) containing 13 lying stalls, a waterer and 35 cm of feed bunk space per animal. Groups were given 3h/d access to an additional space (23 × 2 m, sand-bedded) adjacent to the home pen under both a free access phase (i.e., with no restriction) and a weighted gate phase (i.e., requiring heifers to push a progressively heavier weight). All heifers used the additional space when provided free access, but the number of animals entering the space declined when access was restricted via a weighted gate. Variation among groups and individuals was observed in both how much time heifers spent in the space and expressed motivation, with maximum weight pushed ranging from 1.5 to 22.5 kg. Heifers willing to push the most weight actually spent less time using the space when access was free. Additionally, heifers' use of the additional space appeared to be influenced by the movements of herd mates. These findings indicate that dairy heifers housed in freestall barns are motivated to access additional space, suggesting that greater opportunities for movement should be considered in housing design and that "empty space" may not represent an appropriate negative control in motivation studies.
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5. Assessing the potential of UV-C as a nonthermal alternative to pasteurization in milk powder processing at pilot-scale for the retention of nutrients.
PMID:日期:2026-09-21This study evaluated UV-C (UV-C) treatment as a non-thermal alternative to pasteurization for cow's milk, with a focus on the retention of nutritionally relevant components during liquid and powder processing. The milk was thermized and subsequently processed either by conventional pasteurization (72°C, 15 s) or UV-C irradiation (3,900 J/m at 4°C), followed by evaporation and spray drying. Microbial inactivation, lipase activity, protein denaturation, amino acid profile, in vitro protein digestibility, immunoglobulin A (IgA) and G (IgG), and vitamin stability were assessed. UV-treated milk showed no significant changes in protein denaturation, amino acid profile and in vitro digestibility compared with raw milk. In contrast to pasteurization, UV-C treatment preserved lipase activity in liquid milk, although no residual activity was detected after evaporation and spray drying. Retention of IgA and IgG was significantly higher in UV-treated liquid milk and milk powder than in pasteurized counterparts. UV-C treatment increased vitamin D concentration in milk preserving its bio-accessibility. Overall, UV-C processing preserved key nutritional and bioactive milk components supporting its potential application in dairy processing.
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6. Supply of a histidine-rich bypass protein source improves productive performance and N efficiency independently of metabolizable Met and Lys.
6. 提供富含组氨酸的过瘤胃蛋白源可在不依赖可代谢蛋氨酸和赖氨酸的情况下改善生产性能和氮效率PMID:日期:2026-09-21The milk protein equation of the Nutrient Requirements of Dairy Cattle 8th Revised Edition includes additive effects of the metabolizable (m-) supply of Met, Lys, Leu, Ile, and His. However, additive effects of those AA in dietary studies have not been reported. This study aimed to evaluate the relationship between dietary level of mHis and of mMet, mLys, and mLeu as a group (MKL) on lactation performance, N efficiency, and metabolism, with a 2 × 2 factorial arrangement of treatments. The 4 diets consisted of low (L) or high (H) mHis (HIS; 2.2 vs 2.7% MP) and L or H levels of mMet (2.4 vs 2.8% MP) and mLys (8.0 vs. 9.0% MP). Although mLeu was aimed to increase along with Met and Lys, higher than expected Leu content in the HIS diet resulted in similar increase for both factors. Thirty-two multiparous lactating Holstein cows (77 ± 17 DIM) were enrolled by DIM and parity in a 4 × 4 Latin square study replicated 8 times with 4 periods of 28 d. The 4 experimental diets contained the same inclusion level of corn silage, alfalfa silage, cottonseed, dry corn grain, fat supplement, urea, and vitamins and minerals, while varying inclusion levels of corn gluten meal, a blood meal-based protein mix, and rumen-protected Met and Lys to increase the metabolizable supply of targeted AA. The L-HIS/L-MKL diet was 15% MP deficient while meeting requirements for NEL. Data were analyzed with a mixed model containing fixed effects of HIS, MKL, HIS × MKL interaction, period, and square, and the random effect of cow within square. Both factors increased DMI to a similar extent (+1 kg/d), but no further increase was observed when combined, indicating antagonistic effects between factors. Accounting for DMI, H-HIS increased the supply of mHis and mLeu by 17 and 21 g/d, respectively, compared with L-HIS. Meanwhile, compared with L-MKL, H-MKL increased the supply of mMet, mLys, and mLeu by 15, 44, and 20 g/d, respectively. Both factors increased circulating concentrations of their respective AA in plasma, except for Leu, and decreased glucose to a similar extent (-2.7 mg/dL), without affecting the concentrations of insulin, nonesterified fatty acids, or triglycerides. The yields of milk, lactose, and > 16C fatty acids were increased only by HIS. The yields of ECM (HIS 1.7 kg/d, MKL 0.9 kg/d), true protein (HIS 74 g/d, MKL 45 g/d), fat (HIS 46 g/d, MKL a trend of 31 g/d), and < 16C and = 16C (a trend for HIS) fatty acids were additively increased by the 2 factors. Plasma and milk urea N concentrations, urinary urea N, and total urinary N outputs were increased by MKL. Meanwhile, HIS only increased MUN and tended to increase urinary urea N output. Under L-MKL, HIS maintained gross N use efficiency, while it recovered the drop induced by H-MKL. Despite non-additive effects on DMI, increasing mHis supply, in addition to mMet, mLys, and mLeu, increased milk protein yield and improved N use efficiency, contradicting the limiting AA theory.
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7. Fusing heterogeneous sensor data using artificial intelligence hybrid models for dairy cattle health anomaly detection.
PMID:日期:2026-09-21This observational study evaluated a hybrid artificial intelligence framework for same day anomaly detection in dairy cows using multimodal sensor data collected under commercial farm conditions. The framework integrated thermal video recorded during routine milking, milking-system measurements, and rumen bolus sensor data from 88 cows. Thermal recordings were processed to extract region-level temperature statistics and deep visual-temporal features using residual convolutional networks and Transformer-based temporal modeling. These thermal features were temporally aligned with production and physiological variables, including somatic cell count, milk yield, electrical conductivity, blood indicators, milk flow, internal body temperature, activity, rumination, and bolus event flags. The fused feature sets were evaluated using several machine-learning classifiers under different modality configurations to assess the contribution of thermal, milking, and bolus data. Model performance depended strongly on modality selection and decision-threshold optimization. The best selected configuration achieved a receiver operating characteristic area under the curve of 0.934 and an F1-score of 0.890, indicating strong discrimination between normal and anomalous health states. Results suggest that production and physiological sensor variables provide strong predictive information, whereas thermal imaging adds complementary value when combined with structured farm data. The proposed framework demonstrates the potential of multimodal artificial intelligence systems to support same day health anomaly detection and decision-support tools for dairy cow health monitoring in real farm environments.
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8. Meta-analysis to predict the effects of extended lactations on milk production and reproductive performance of dairy cows.
8. 用于预测延长泌乳期对奶牛产奶量和繁殖性能影响的Meta分析PMID:日期:2026-09-21The effects of extended lactation (EXTL) on milk production and reproductive performance of dairy cows were quantified using a meta-analysis approach. A systematic literature review was conducted to identify studies that compared milk yield and reproductive performance between cows managed within EXTL systems and those managed under conventional lactation length, resulting in 21 studies eligible for inclusion in the meta-analysis. Data collected from those studies included calving interval (CInt), voluntary waiting period (VWP), parity, breed, farm type (experimental vs. commercial), and whether cows were selectively assigned to EXTL based on production and cow characteristics or randomly allocated. Corresponding treatment means were extracted for energy-corrected milk yield per calving interval day (ECM/CInt), first service conception rate, and number of inseminations per conception. Mixed-effects models were developed for each outcome, with study as a random effect. The models included CInt as the main predictor for ECM/CInt and VWP for first service conception rate and number of inseminations per conception, along with other covariates that were retained if significant. A separate subgroup analysis was conducted to compare studies using selective versus random assignment to EXTL. The relationship between CInt length and ECM/CInt differed by parity, where each 10-d increase in CInt was associated with a 0.08 kg/d increase in ECM/CInt in primiparous cows, while no effect of CInt length on ECM/CInt was observed in multiparous cows. Selective assignment of multiparous cows to EXTL, based on individual cow characteristics and production traits, tended to be associated with 1.9 kg/d higher ECM/CInt compared with randomized allocation, although production of cows selectively assigned to EXTL was similar to that of conventionally managed cows. In addition, criteria used to identify cows suitable for EXTL were variable between studies, and no consistent or clearly effective selection method could be determined. Reproductive performance improved with extended VWP across parities; each 10-d increase in VWP was associated with a 0.02 unit decrease in inseminations per conception and higher odds of first service conception (1.1 × in multiparous cows and 1.04 × in primiparous cows). Overall, the results of this meta-analysis indicate that EXTL improves measures of reproductive performance in both parity groups and increases ECM/CInt in primiparous cows, whereas the response in milk yield of multiparous cows depends on whether the EXTL strategy was selectively implemented. These results indicate that EXTL, if implemented, should be applied as an individualized rather than a herd-level strategy.
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9. Climate-smart dairy practices and perceptions across 2 global dairy producing countries.
9. 全球两个乳制品生产国的气候智慧型乳业实践与认知PMID:日期:2026-09-21Both in the United States and internationally, the dairy sector has set ambitious targets to reduce greenhouse gas emissions and implement climate-smart agriculture practices. Despite this, little research has explored dairy producer perceptions or adoption of climate-smart practices, especially across contexts. This study presents the first comparison study of dairy producer adoption and perceptions around climate-smart practices across 2 major dairy-producing countries, New Zealand and the United States. Data were collected through 2 online surveys (deployed in 2023 US and 2025 in New Zealand), which were developed to reflect contextual differences for each respective country and included current and anticipated adoption of climate adaptation and mitigation practices, beliefs around climate change and anticipated climate impacts on the dairy industry, herd information, and producer demographics. We find that while dairy producers are adopting climate-smart practices relevant to the production systems in both countries, NZ producers (n = 306) displayed higher likelihood of adoption of emerging enteric mitigation strategies such as feed additives, selective breeding, and methane-inhibiting vaccines, as well as a higher proportion of anthropogenic climate change belief, compared with US producers (n = 920, approximately 700 full responses). Across both countries, cow welfare, farm profitability, and ensuring a viable farming operation for future generations were the top considerations when adopting new practices, suggesting these are critical to support farmers' climate-related strategy adoption. Despite having greater policy support and incentive programs for climate-smart practices, US producers were more likely to perceive initial cost and equipment barriers, to adopting climate-smart practices, while NZ producers were more likely to perceive information and technical assistance barriers. Finally, producers in both countries had high levels of uncertainty about how climate change may impact their operations, indicating that local and regionally appropriate climate risk extension and outreach engagement is important. These results provide key insights for stakeholders who seek to increase adoption of climate-smart dairy practices to meet industry and government expectations.
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10. Investigation of laparoscopic ovum-pickup in juvenile heifers followed by in vitro embryo production and embryo transfer in dairy cattle.
10. 对青年母牛进行腹腔镜活体采卵后进行体外胚胎生产及胚胎移植的研究PMID:日期:2026-09-21The objectives of this pilot study were (1) to investigate the potential application of juvenile in vitro fertilization and embryo transfer (JIVET) in seasonal pasture based dairy systems and (2) to provide insights into donor and recipient management that might be useful in designing future studies. Oocytes were collected from the ovaries of elite Holstein Friesian donor calves (n = 49) by laparoscopic ovum pickup. Following in vitro maturation, oocytes were fertilized with frozen-thawed X-sorted semen from a panel of proven fertility Holstein Friesian sires (n = 8) and cultured for 7 d. A total of 87 embryos were transferred fresh to Holstein Friesian heifers or lactating dairy cows that had been synchronized using a progesterone-Ovsynch protocol. Pregnancy diagnosis was carried out using transrectal ultrasound at d 35 after synchronized estrus and was confirmed at d 63. Pregnancy loss was characterized as loss between d 35 and d 63. Gestation length (GL), birthweight (BiW), calving difficulty (CD) and vitality scores were recorded from the resulting calves (n = 21) and a contemporaneous cohort of calves derived from artificial insemination (AI; n = 44). Blood samples were collected from a subset (n = 35) of these calves for hematological analysis on d 0 and biochemical analysis on d 0 and d 14. There was evidence that the number of blastocysts produced (0.3 vs 2.1), and blastocyst yield (percentage of presumptive zygotes that formed blastocysts; 0.8% vs 15.1%) were both less for donors that had experienced a health event before LOPU than for those that had not. Fewer oocytes were recovered from donors that were in the bottom 25% category for plasma anti-Müllerian hormone (AMH) compared with those in the middle 50% category, and these in turn had lower oocyte recovery compared with donors in the top 25% category (3.9, 8.1 and 26.9, respectively). Fewer transferrable embryos were produced from donors that were in the bottom 25% category for plasma AMH compared with those in the middle 50% and the top 25% category (0.6, 1.1 and 4.4, respectively). Mean serum concentration of pregnancy specific protein-B (PSPB) on d 21 was lowest in recipients that were diagnosed not pregnant on d 35 (0.16 ng/mL) and was greatest in recipients that maintained the pregnancy to term (0.96 ng/mL). Gestation length and BiW were similar for calves derived from AI and JIVET. Calving difficulty and calf vigour scores were not affected by calf origin. In conclusion, donor calf health before LOPU and plasma AMH concentration were associated with subsequent embryo yield, and calves derived from JIVET had similar GL, BiW, CD and calf vigour scores to AI-derived calves.