Journal of Dairy Science最新文献

{"title":"The effect of meloxicam at the time of treatment of hoof-horn lameness in pasture-grazing dairy cattle on time to lameness soundness, pregnancy risk, and time to conception: A randomized control trial","authors":"W.A. Mason ,&nbsp;J. Laidlaw","doi":"10.3168/jds.2024-25537","DOIUrl":"10.3168/jds.2024-25537","url":null,"abstract":"<div><div>The aims of this study were to assess the effect of meloxicam at the time of lameness treatment for hoof-horn (HH) lesions in dairy cattle on (1) time to lameness soundness after trimming and block application and (2) reproductive success. Five seasonal-calving pasture-based dairy farms located in the Waikato region of New Zealand were enrolled into a randomized clinical interventional trial. Farmers were tasked with identifying lame animals over a period of approximately −4 to 6 wk relative to the herd start of mating (HSM), with lameness subsequently confirmed with lameness score (LS) by trained technicians (0–3 scale, where ≥2 are considered lame). Animals with a LS ≥2 were examined by a veterinarian who then enrolled animals if they presented lame with HH (white line or sole) lesions. This same veterinarian then provided therapeutic hoof trimming, and application of wooden blocks, to the enrolled lame animals. Randomization into either meloxicam (0.5 mg/kg s.c.) or negative control groups was conducted after trimming, with animals blocked by farm and lesion. Following lameness treatment, animals were lameness scored at a median interval of every 4 d until sound (LS = 0), with scoring occurring regardless of block retention status; blocks were not removed at any stage. Animals had conception date and pregnancy status confirmed via rectal ultrasound. Outcomes were number of days to soundness (animals may still have block on) and number of days from HSM to conception, and binary outcomes of pregnant within 6 wk of the breeding period and final pregnancy status. Cox proportional-hazard methods were used to analyze the time-to-event outcomes, with binary outcomes analyzed using multivariable logistic regression methods. A total of 241 animals were enrolled, 123 into the meloxicam group and 118 into the control group. The majority of lesions were described as white line (225; 93%), with 207 (86%) animals receiving wooden blocks on the nonlame hoof. No improvement in the time to soundness was reported between animals in the 2 treatment groups (hazard ratio 0.78; 95% CI 0.56–1.03 for meloxicam-treated animals compared with control animals), with most scoring events occurring with a block present. From the 229 animals with reproductive outcome data (117 meloxicam treated and 112 control treated), the hazards of conception in meloxicam-treated animals were 1.42 (95% CI 1.06–1.90) times that for the control animals. Meloxicam-treated lame animals had 15% greater predicted probabilities of conceiving within the first 6 wk of the breeding period and final pregnancy status, respectively, compared with control lame animals. The addition of meloxicam to the treatment regimen of lame dairy cattle with HH lesions can significantly improve reproductive outcomes, despite no apparent difference in time to soundness.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3991-4004"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942190","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 effect of the biohydrogenation-induced milk fat depression in dairy cows on milk odd- and branched-chain fatty acids across multiple studies","authors":"M. Arif,&nbsp;E. Palmer ,&nbsp;M. Baldin ,&nbsp;D.E. Rico ,&nbsp;K.J. Harvatine","doi":"10.3168/jds.2024-25572","DOIUrl":"10.3168/jds.2024-25572","url":null,"abstract":"<div><div>Diet-induced milk fat depression (MFD) caused by UFA and low-fiber diets results in an increase in alternate rumen biohydrogenation intermediates. The effect of these MFD-inducing diets on milk odd- and branched-chain fatty acids (OBCFA) is not well known. The first objective of this study was to characterize the time course of changes in OBCFA in milk fat during induction and recovery of MFD induced with a high-UFA and low-fiber diet in 3 separate experiments. In the first experiment, milk OBCFA were quantified in a previous experiment that sampled milk fat every other day during induction and recovery of MFD. Induction of MFD decreased all OBCFA in milk fat except <em>iso</em> 17:0, which was increased by 15%. The temporal response varied among OBCFA, with <em>iso</em> 15:0, <em>anteiso</em> 15:0, 17:0, <em>anteiso</em> 17:0, and total <em>anteiso</em> FA and OBCFA progressively decreasing after the first day, while <em>iso</em> 14:0, <em>iso</em> 16:0, and total <em>iso</em> FA decreased after d 5. The OBCFA progressively increased during recovery, and most were similar to the control by d 3. Two additional experiments investigated the change in milk OBCFA during recovery from MFD with diets that differed in UFA, fiber, or monensin supplementation. The effect of MFD on milk OBCFA was similar to the results from experiment 1 and the temporal response during recovery was similar to recovery of normal rumen fermentation. The second objective was to characterize the response across MFD experiments conducted in our research group. The database included 7 experiments that fed either a control diet or a diet that caused MFD through either a change in fiber, UFA, or both. The MFD diet decreased most OBCFA in milk fat, including <em>iso</em> 14:0, 15:0, <em>iso</em> 15:0, <em>anteiso</em> 15:0, <em>iso</em> 16:0, 17:0, <em>anteiso</em> 17:0, and the sum totals of <em>iso</em> FA, <em>anteiso</em> FA, and OBCFA. However, <em>iso</em> 17:0 and <em>cis</em>-9 17:1 were not different between the control and MFD diets. In conclusion, milk OBCFA other than <em>iso</em> 17:0 and <em>cis</em>-9 17:1 are reduced when feeding a diet that causes biohydrogenation-induced MFD and the temporal response was similar to the alternate rumen biohydrogenation intermediates and likely indicates the time course of adaptation of rumen microbial populations and fermentation during these diet alterations.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3544-3559"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942194","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":"Early-life nutrition and its effects on the developing heifer: Growth, nutritive intakes, and metabolism","authors":"E.M. Ockenden ,&nbsp;V.M. Russo ,&nbsp;B.J. Leury ,&nbsp;K. Giri ,&nbsp;W.J. Wales","doi":"10.3168/jds.2024-25546","DOIUrl":"10.3168/jds.2024-25546","url":null,"abstract":"<div><div>We aimed to assess the effects of preweaning nutrition and postweaning growth rates on the metabolic characteristics of replacement dairy heifers until 20 mo of age. At birth, heifers were allocated to 1 of 4 treatment groups, which were a combination of preweaning (high or low preweaning nutritional treatment) and postweaning treatments (high or low postweaning growth rate). In the preweaning phase (birth until weaning at 10 wk of age), heifers were subject to either a high (8 L/d) or a low (4 L/d) milk feeding strategy; then, at weaning, either a high or a low postweaning growth rate. Heifers in the high preweaning treatment groups recorded greater growth rates until weaning compared with heifers in the low preweaning treatment groups. Heifers in the high preweaning groups consumed approximately twice the amount of milk and half the amount of concentrate. Blood samples taken at 6 wk of age had lower BHB and higher glucose and IGF-1 concentrations in the high preweaning treatment in the preweaning phase; these differences disappeared postweaning. Additionally, insulin levels were also higher, and quantitative insulin sensitivity check index (QUICKI) results were lower for heifers on the high preweaning treatment and for those on the high postweaning treatment at 6 wk and 13 mo of age. No differences between treatments were detected at 8 mo of age. Results indicate a positive effect of accelerated preweaning nutrition and postweaning growth rate (at 13 mo of age) on these metabolic biomarkers; however, these treatment effects were independent of one another and reflected the nutritional input at the time.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3515-3528"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142942257","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 low-phosphorus diets on phosphorus balance, plasma concentrations of 25-hydroxyvitamin D3, and carboxy-terminal collagen crosslinks during the transition period in dairy cows","authors":"P. Keanthao ,&nbsp;R.M.A. Goselink ,&nbsp;J. Dijkstra ,&nbsp;A. Bannink ,&nbsp;J.T. Schonewille","doi":"10.3168/jds.2024-25463","DOIUrl":"10.3168/jds.2024-25463","url":null,"abstract":"<div><div>Our aim was to determine the effects of P intake on P balance, serum parathyroid hormone (PTH) levels, and bone resorption during the final 4 wk prepartum and the first 8 wk of lactation. Sixty pregnant multiparous Holstein Friesian dairy cows were assigned to a randomized block design with repeated measurements and dietary treatments arranged according to a 2 × 2 factorial design. The experimental diets contained 3.6 (high phosphorus [HP]) or 2.2 (low phosphorus [LP]) g P/kg DM during the dry period (Dry-HP and Dry-LP, respectively), and 3.8 or 2.9 g P/kg DM during 56 d after calving (Lac-HP and Lac-LP, respectively). The level of dietary P of Dry-LP, expressed as g/kg DM, was 18% greater than recommended by the Dutch Central Bureau for Livestock Feeding (The Hague, the Netherlands), whereas the P content of Lac-LP was, across the 8 wk of lactation, 24% lower than recommended. Both P intake and fecal P excretion decreased in the dry period to increase again in subsequent lactation. Cows fed high dietary P excreted more P in the feces than cows fed low dietary P pre- and postpartum. Cows in both Dry-HP and Dry-LP were in positive P balance in the dry period. Cows in both Lac-LP and Lac-HP were in negative P balance after calving, with the negative P balance being more pronounced in Lac-LP than in Lac-HP. Serum concentrations of PTH and apparent total-tract OM and NDF digestibility were neither affected by any 2-way or 3-way interaction between time of sampling and dietary treatments nor by the P concentration of the experimental diets during the pre- and postpartum period. Before calving, serum carboxy-terminal collagen crosslink (CTX) concentrations were basically similar between Dry-HP and Dry-LP. After calving, serum CTX concentrations increased, with a more pronounced increase when Lac-LP was fed compared with Lac-HP. The results suggest that when feeding diets containing low P (2.9 g/kg DM) postpartum, cows excreted less P in the feces than at recommended dietary P (3.8 g P/kg DM) without a negative impact on OM and NDF digestibility. The increase in serum CTX concentrations, without increasing serum PTH concentrations upon feeding low P, indicate a prominent role of bone resorption to meet P demands in the first 8 wk postpartum. The present trial focused on the final 4 wk of gestation and the subsequent 8 wk of lactation, but long-term effects of low dietary P during early lactation on serum PTH and on bone P dynamics in mid and late lactation need to be further investigated.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3602-3612"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142997714","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 a functional milk powder supplemented with rhizoma drynariae extracts on bone health in growing and ovariectomized rats: More effective for lumbar vertebrae?","authors":"Wenjing Wu ,&nbsp;Mengqi Yu ,&nbsp;Yan Liu ,&nbsp;Xiaoya Wang ,&nbsp;Liang Wang ,&nbsp;Qijie Wei ,&nbsp;Haotian Feng ,&nbsp;Jinyao Chen","doi":"10.3168/jds.2024-25896","DOIUrl":"10.3168/jds.2024-25896","url":null,"abstract":"<div><div>Bone health is vital through all life stages and has become a growing public health concern. The role of rhizoma drynariae (RD) as a traditional Chinese medicine for bone injury recovery has been widely investigated. Still, there is little research related to RD as a functional component in food to improve calcium bioavailability and bone health. Milk powder is a daily vital food source of dietary calcium. The present study aimed to investigate and compare the effects of a functional milk powder reinforced with RD extracts (RDE) or vitamin D, vitamin K₂, and calcium, or both, using Sprague-Dawley rats, with both low calcium growing rat model and low calcium ovariectomized (OVX) rat model. For growing rats, RDE increased bone mineral density (BMD) and improved the microstructure of bone trabecula in the femur and lumbar vertebrae. The levels of serum bone turnover markers C-telopeptide of type Ⅰ collagen (CTX-I), procollagen type Ⅰ amino-terminal peptide (PINP), and osteocalcin (BGP) were increased with RDE supplementation. The tartrate-resistant acid phosphatase staining suggested a decrease in the number of osteoclasts in the femur. Immunohistochemistry showed that the osteoclast-related protein RANKL was downregulated, and the osteogenic-associated proteins RUNX2 and OSX significantly increased in the lumbar vertebrae. Similarly, in OVX rats, RDE improved BMD and microstructure in lumbar vertebrae, and the levels of CTX-I, PINP, and BGP were also increased. In conclusion, the novel functional milk powder supplemented with RDE facilitated osteogenesis and inhibited osteoclast in rats at both stages, especially with lumbar vertebrae in growing rats. Our findings provide new prospects and a more precise target for enhancing bone health by incorporating RDE as a functional component in milk powder.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3480-3498"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143073254","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":"Hypoxia-inducible factor 2α mediates nonesterified fatty acids and hypoxia-induced lipid accumulation in bovine hepatocytes","authors":"Fanrong Kong ,&nbsp;Lin Lei ,&nbsp;Lin Cai ,&nbsp;Jinxia Li ,&nbsp;Chenchen Zhao ,&nbsp;Menglin Liu ,&nbsp;Dandan Qi ,&nbsp;Jie Gao ,&nbsp;Enzhu Li ,&nbsp;Wenwen Gao ,&nbsp;Xiliang Du ,&nbsp;Yuxiang Song ,&nbsp;Guowen Liu ,&nbsp;Xinwei Li","doi":"10.3168/jds.2024-25839","DOIUrl":"10.3168/jds.2024-25839","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Ketosis is a metabolic disorder frequently occurring in the perinatal period, characterized by elevated circulating concentrations of nonesterified fatty acids (NEFA) due to negative energy balance, resulting in fatty liver in dairy cows. However, the mechanism of hepatic steatosis induced by high concentrations of NEFA in ketosis remains unclear. Hypoxia-inducible factor 2α (HIF-2α), which mediates adaptation to hypoxic stress, plays a critical role in regulating lipid metabolism. In this study, we investigate whether HIF-2α is involved in NEFA-driven hepatic lipid accumulation in dairy cows with ketosis. Liver and blood samples were collected from 10 healthy cows (blood BHB concentration &lt;1.2 m&lt;em&gt;M&lt;/em&gt;) and 10 ketotic cows (blood BHB concentration &gt;3.0 m&lt;em&gt;M&lt;/em&gt; with clinical symptoms) with similar lactation numbers (median = 3, range = 2–4) at 3 to 9 DIM (median = 6). In cows with ketosis, serum concentrations of NEFA and BHB were greater, but serum concentrations of glucose were lower. Moreover, hepatic triglyceride content increased significantly. In the liver of ketotic cows, which was accompanied by upregulated HIF-2α expression. To determine the potential association among hypoxia, HIF-2α, and the formation of hepatocellular steatosis in vitro, we isolated hepatocytes from healthy calves for the following experiments. First, hepatocytes were treated with 0, 0.6, 1.2, or 2.4 m&lt;em&gt;M&lt;/em&gt; NEFA (52.7 m&lt;em&gt;M&lt;/em&gt; stock NEFA solution was diluted in RPMI-1640 basic medium supplemented with 2% fatty acid-free BSA to achieve the specified concentrations) for 18 h, showing that HIF-2α expression and cellular hypoxia occurred in a dose-dependent manner. Next, hepatocytes were infected with HIF-2α (encoded by &lt;em&gt;EPAS1&lt;/em&gt;) small interfering RNA (Si-HIF-2α) for 48 h and then treated with 1.2 m&lt;em&gt;M&lt;/em&gt; NEFA for 18 h. Results indicated that silencing HIF-2α decreased NEFA-induced lipid accumulation in bovine hepatocytes. Subsequently, hepatocytes treated with or without NEFA were placed in an AnaeroPack System, mimicking a hypoxic condition, for 0, 12, 18, or 24 h. Results showed that hypoxia could induce and further exacerbate lipid accumulation in bovine hepatocytes. Meanwhile, normal or NEFA-treated hepatocytes were cocultured with or without PT2385, a specific HIF-2α inhibitor, showing that hypoxia promoted steatosis through HIF-2α. Activating transcription factor 4 (ATF4) is an endoplasmic reticulum (ER) stress and hypoxia-inducible transcription factor. Here, bovine hepatocytes were treated with NEFA or hypoxia following transfecting ATF4 small interfering RNA, which demonstrated that ATF4 knockdown alleviated the extent of lipid accumulation in bovine hepatocytes. In addition, we found that ATF4 expression was correlated with HIF-2α levels in both liver tissue and cultured hepatocyte models. Moreover, overexpression of ATF4 weakened the beneficial effects of HIF-2α inhibition. Overall, these data suggest that NEFA-induced ","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 4062-4078"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143073273","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 clove (Syzygium aromaticum) extract on antibacterial activity, phytochemical properties, and storage quality of flavored milk beverages","authors":"Maha M. Bikheet ,&nbsp;Hanaa M. Hassan ,&nbsp;Maha O.A. Omar ,&nbsp;Waled M. Abdel-Aleem ,&nbsp;Salma M. Galal ,&nbsp;Sameh A. Korma ,&nbsp;Salam A. Ibrahim ,&nbsp;Khaled S. Nassar","doi":"10.3168/jds.2024-26023","DOIUrl":"10.3168/jds.2024-26023","url":null,"abstract":"<div><div>The antibacterial efficacy of clove extracts (<em>Syzygium aromaticum</em>) prepared using 80% ethanol and water against pathogenic bacteria was evaluated, along with the development of a novel antimicrobial milk beverage incorporating these extracts. Seven flavored milk beverage (FMB) treatments were prepared: a control and 6 with clove extracts at 0.5%, 0.7%, and 1% for each solvent. The effects on physicochemical, phytochemical, antioxidant, microbiological, color, and sensory properties were assessed over 15 d of storage at 4 ± 1°C. The ethanolic clove extract exhibited significantly higher antimicrobial activity against <em>Staphylococcus aureus, Listeria monocytogenes, Escherichia coli</em> O157, <em>Salmonella typhi,</em> and <em>Klebsiella pneumoniae</em>, with inhibition zone diameters of 20 mm, 21 mm, 20 mm, 19 mm, and 20 mm, respectively, compared with the aqueous extract. On d 0, the sample of 1% ethanolic clove extract (FMB3) showed the highest proximate analysis values, including TS (22.41%), protein (4.61%), fat (4.58%), ash (0.97%), and gross energy (108.65 Kcal). It also showed the highest pH (6.7), flavor score (19.20), texture score (9), and overall acceptability score (39.50), and the lowest carbohydrate content (12.27%), lightness value (69.60), and yellowness value (97.47). Over the 15-d storage period, the total phenolic content (TPC), total flavonoid content (TFC), and total antioxidant capacity (TAC) increased, with the FMB3 sample exhibiting the highest TPC (58.70 mg/100 g), TFC (46.15 mg/100 g), and TAC (487.10 mg/100 g). All beverages remained free from yeasts and molds, and FMB3 exhibited the lowest bacterial count (5.13 log cfu/mL). The results indicate that ethanolic clove extract effectively inhibits spoilage and pathogenic organisms and enhances the sensory and functional properties of FMB. This finding offers a promising approach for improving the quality and safety of dairy products.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3300-3313"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143412719","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 role of glutathione S-transferase mu 2 in mitigating fatty acid–induced hepatic inflammation in dairy cows","authors":"Jinxia Li ,&nbsp;Chenchen Zhao ,&nbsp;Dandan Qi,&nbsp;Fanrong Kong,&nbsp;Menglin Liu,&nbsp;Jie Gao,&nbsp;Enzhu Li,&nbsp;Wenwen Gao,&nbsp;Xiliang Du,&nbsp;Yuxiang Song,&nbsp;Xinwei Li,&nbsp;Haihua Feng,&nbsp;Lin Lei","doi":"10.3168/jds.2024-25740","DOIUrl":"10.3168/jds.2024-25740","url":null,"abstract":"<div><div>Fatty liver is a major metabolic disorder in perinatal dairy cows, characterized by elevated plasma concentrations of nonesterified fatty acids (NEFA) and hepatic inflammation. Glutathione S-transferase mu 2 (GSTM2), a phase II detoxification enzyme, regulates cellular antioxidant and detoxification processes in nonruminants. However, its involvement in NEFA-induced hepatic inflammation in dairy cows with fatty liver remains unclear. This study aimed to elucidate the role of GSTM2 in mediating hepatic inflammation caused by elevated NEFA levels in dairy cows with severe fatty liver. An in vivo study was conducted using 10 healthy cows (hepatic triacylglycerol [TG] content &lt;1%) and 10 cows with severe fatty liver (hepatic TG content &gt;10%), matched for the number of lactations (median = 3, range = 2–4) and DIM (median = 9 d, range = 3–15 d). Liver tissue and blood samples were collected before feeding. Compared with healthy cows, cows with severe fatty liver had higher plasma concentrations of NEFA, BHB, haptoglobin (HP), plasma amyloid A (SAA), and lower plasma concentration of glucose. These cows also showed significantly lower abundance of hepatic GSTM2 and overactivated hepatic inflammatory pathways, as indicated by increased abundance of phosphorylated inhibitor of κB (IκB)α and nuclear factor κB (NF-κB) p65, NLR family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein containing CARD (ASC), and caspase-1 (CASP1), as well as mRNA levels of tumor necrosis factor α (<em>TNFA</em>), <em>IL6</em>, and <em>IL1B</em>. In vitro, hepatocytes isolated from 5 healthy calves (1 d old, fasted female, 30–40 kg of BW) were used to determine the effects of GSTM2 on hepatic inflammation. First, hepatocytes were treated with NEFA (1.2 m<em>M</em>) for varying durations (0.5, 1, 3, 6, 9, 12, 15, or 18 h). The NEFA treatment significantly increased the phosphorylation of IκBα and NF-κB p65, protein abundance of NLRP3, ASC and CASP1, and mRNA levels of <em>TNFA</em>, <em>IL6</em> and <em>IL1B</em>, peaking at 9 and 12 h. Second, hepatocytes were treated with different concentrations of NEFA (0, 0.6, 1.2, or 2.4 m<em>M</em>) for 9 h, which decreased GSTM2 protein and mRNA abundance. Meanwhile, GSTM2 was silenced using small interfering RNA or overexpressed using adenovirus for 48 h in hepatocytes, followed by NEFA treatment. Silencing GSTM2 augmented the NEFA-induced increase in phosphorylation of IκBα and NF-κB p65, as well as protein abundance of NLRP3, ASC and CASP1, and mRNA levels of <em>TNFA</em>, <em>IL6</em> and <em>IL1B</em>. Conversely, overexpression of GSTM2 mitigated these inflammatory signals upon NEFA treatment. In summary, these findings indicate that GSTM2 plays a crucial role in modulating NEFA-induced hepatic inflammation. Targeting GSTM2 may offer new strategies to treat or prevent fatty liver disease in dairy cows.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 4149-4162"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143412732","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":"Associations between days open and dry period length versus milk production, replacement, and fertility in the subsequent lactation in Holstein dairy cows","authors":"Michael W. Overton ,&nbsp;Steve Eicker","doi":"10.3168/jds.2024-26055","DOIUrl":"10.3168/jds.2024-26055","url":null,"abstract":"&lt;div&gt;&lt;div&gt;A retrospective, observational approach was used to investigate the association between days open and dry period length in one lactation, and survivability, production, and reproductive performance in the subsequent lactation. Animal-level data from 60 intensively managed, year-round-calving US Holstein herds were collected. A subset of this larger dataset was identified that also had recorded genomic test results including Dairy Wellness Profit Index (DWP$). Data from 109,374 cows comprised the larger dataset (AllCows), and 37,680 cows comprised the genomics subset (GenCows). Average days open of the previous lactation (PDOPN) was 114 d, and the average dry period length (PDDRY) before the lactation of interest was 58. Response outcomes had a standard endpoint of 90 DIM of the subsequent lactation and included proportion replaced, cumulative milk production (CUM90), and proportion pregnant. Proportion replaced and proportion pregnant were analyzed using multivariable logistic regression. Milk production was analyzed using a linear mixed model. Continuous explanatory variables included previous lactation 305-d ME milk (P305ME), wk-36 milk (WM36), PDOPN, PDDRY, and DWP$ (GenCows only). Categorical variables included previous lactation parity group (PLCTGP 1, 2, or 3+), calf type (female, male, or twins), and number of clinical mastitis (NMAST) or clinical lameness (NLAME) events recorded in the previous lactation. Both diseases were classified based on the number of cases recorded (0, 1, or 2+ cases). Important 2-way interactions were also considered. Increases in PDOPN were associated with increased odds of replacement, whereas the effect of PDDRY varied in a curvilinear manner, with shortest and longest PDDRY associated with highest odds of replacement. Odds of replacement increased with each increase in PLCTGP and with higher levels of recorded mastitis or lameness. Calf type was significant; delivery of twins was associated with a higher risk of replacement than a male calf. A female calf had the lowest risk of replacement than either male calf or twins. Higher P305ME was associated with lower odds of replacement. Increasing values of DWP$ were associated with reduced odds of replacement. Higher P305ME was associated with greater CUM90. Both NMAST and twins were associated with reduced CUM90. Higher DWP$ was associated with greater CUM90. The lowest PDOPN and PDDRY were associated with the highest risk of pregnancy, but the magnitude of the negative effect of PDOPN increased as PLCTGP increased. Increasing levels of P305ME had a small negative statistical association with risk of pregnancy, which is biologically insignificant. Twins, NMAST, and NLAME each had large negative effects on the odds of pregnancy by 90 DIM. Meanwhile, increases in DWP$ were associated with increased odds of achieving pregnancy. Despite significant differences between parity groups, the overall conclusion is that cows should be managed to conceive earlier ra","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3764-3779"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143475953","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":"Invited review: Management of genetic defects in dairy cattle populations","authors":"John B. Cole ,&nbsp;Christine F. Baes ,&nbsp;Sophie A.E. Eaglen ,&nbsp;Thomas J. Lawlor ,&nbsp;Christian Maltecca ,&nbsp;M. Sofía Ortega ,&nbsp;Paul M. VanRaden","doi":"10.3168/jds.2024-26035","DOIUrl":"10.3168/jds.2024-26035","url":null,"abstract":"<div><div>When related animals are mated to one another, genetic defects may become apparent if recessive mutations are inherited from both sides of the pedigree. The widespread availability of high-density DNA genotypes for millions of animals has made it possible to identify and track known defects as well as to identify and track previously unknown defects that cause early embryonic losses. Although the number of known defects has increased over time, the availability of carrier information has been used to dramatically reduce the frequency of many disorders. The economic impact of known genetic defects in the US dairy cattle population has decreased by ∼2/3 since 2016, due largely to the avoidance of carrier-to-carrier matings. Effective population management requires robust systems for reporting new defects, identification of causal mechanisms, and development of commercially available tests. The United States and Canada depend on informal cooperation among many groups, including farmers, purebred cattle associations, genetics companies, and researchers, to identify emerging and causal defects. The structure of a collaborative system including all key sectors of the dairy cattle industry to support long-term population management is described. This review provides a comprehensive overview of the landscape surrounding genetic defects in dairy cattle. Topics covered include current defects of relevance to commercial dairy producers, trends in carrier frequencies over time, how best to manage these defects, strategies for detecting emerging diseases, and marketing and trade considerations.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 4","pages":"Pages 3045-3067"},"PeriodicalIF":3.7,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143476036","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}