Journal of Dairy Science最新文献

{"title":"Potential involvement of peroxisome proliferator-activated receptors in the inhibition of mammary lipid synthesis during diet-induced milk fat depression","authors":"A. Haile ,&nbsp;D.E. Oliveira ,&nbsp;Y.R. Boisclair ,&nbsp;D.E. Bauman ,&nbsp;K.J. Harvatine","doi":"10.3168/jds.2024-25575","DOIUrl":"10.3168/jds.2024-25575","url":null,"abstract":"<div><div>The objective of this study was to evaluate the possible role of the peroxisome proliferator-activated receptors (PPAR: PPAR-α, PPAR-β/δ, and PPAR-γ) in diet and CLA-induced milk fat depression (MFD) in dairy cows. We hypothesized that the expression of PPAR, which regulate lipid metabolism and bind to PUFA, could be modulated by biohydrogenation intermediates that induce MFD, thereby interfering with milk fat synthesis. First, tissue profiling revealed that PPAR-α and PPAR-β/δ had low expression in mammary tissue compared with the liver. A comparison of lactating and nonlactating tissue from the same cows showed that expression of all 3 PPAR isoforms did increase during lactation. Mammary expression of the <em>PPAR</em> family during MFD was then observed in 9 mid-lactation cows in a 3 × 3 Latin square design with MFD induced by a 3-d intravenous infusion of <em>trans</em>-10,<em>cis</em>-12 CLA or feeding a high-oil and low-forage diet. The expression of all 3 PPAR isoforms remained largely unaltered during CLA and diet-induced MFD, except for an increase in PPAR-α target genes <em>CPT1A</em> and <em>ACADVL</em> that are involved in β-oxidation. The interaction of PPAR-γ chemical agonist troglitazone and antagonist T0070907 and CLA was then investigated in bovine mammary epithelial cells. The activation and inhibition of PPAR-γ did not overcome <em>trans</em>-10,<em>cis</em>-12 CLA inhibition of lipogenesis despite the agonist stimulating PPAR-γ expression. Furthermore, PPAR-γ activation did not modify the expression of lipogenic genes. Overall, the results fail to support a functional role of the PPAR family in the inhibition of lipogenesis during MFD in dairy cows.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 2036-2044"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142610995","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 heat stress abatement on behavioral response in lactating dairy cows prior to and following an intramammary lipopolysaccharide infusion","authors":"T.N. Marins ,&nbsp;R.M. Orellana Rivas ,&nbsp;Y-C. Chen ,&nbsp;V.H.L.R. Melo ,&nbsp;Z. Wang ,&nbsp;H. Liu ,&nbsp;J. Gao ,&nbsp;C.G. Savegnago ,&nbsp;A.M. Roper ,&nbsp;J.K. Bernard ,&nbsp;P. Melendez ,&nbsp;S. Tao","doi":"10.3168/jds.2024-25298","DOIUrl":"10.3168/jds.2024-25298","url":null,"abstract":"<div><div>The assessment of animal behavior serves as a valuable approach to identify illness and animal responses to environmental stimuli. Both heat stress and mastitis are reported to affect the behavioral responses of dairy cattle. However, little is known about the effects of heat stress on the lactating cow's behavioral responses to mastitis. The aims of the current study were to evaluate the effects of deprivation of evaporative cooling on behavioral responses of lactating dairy cows before and following mammary inflammation induced by intramammary LPS (IM-LPS) infusion and to characterize the effect of deprivation of evaporative cooling on feed sorting in lactating dairy cows during summer. Multiparous mid-lactating Holstein dairy cows (n = 18, parity = 2.4 ± 0.6, DIM = 136 ± 61 d) were randomly assigned to: evaporatively cooled (CL, n = 9) or not cooled (NC, n = 9) for 36 d (average temperature-humidity index = 78.4). The evaporative cooling system included misters and fans. Misters were installed on the front face of each fan, which was placed over both feed bunk and freestalls. On d 30, the left rear quarters of a subset of cows (n = 14, 7 per treatment) were infused with a bolus of LPS (10 µg of <em>Escherichia coli</em> O111:B4 LPS). Feeding and resting behaviors were recorded throughout the experiment using automated sensor devices (NEDAP). Sorting activity based on particle size separation using a Penn State Particle Separator was assessed at d 3, 16, and 26 of the experiment. Before IM-LPS, NC cows had lower ruminating and eating time, and consequently greater inactive time compared with CL cows. Relative to CL cows, NC cows had reduced lying time, and greater standing and walking time. The NC cows also had greater standing bouts, only at the beginning of the experiment, relative to CL cows. Additionally, NC cows sorted more for long particles (NC: 99.4% vs. CL: 94.4%) and sorted against medium and short particles on d 3 of the experiment compared with CL cows. However, following IM-LPS, no significant differences in behavioral responses were observed between NC and CL cows. In conclusion, deprivation of evaporative cooling negatively affected the behavioral responses of lactating dairy cows during summer. Further, heat-stressed cows without evaporative cooling sorted more for long particles of the diet potentially as a response to cope with the reduced rumen pH. However, deprivation of evaporative cooling does not have a significant effect on the lactating cow's behavioral responses to LPS induced mammary inflammation.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1882-1895"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611532","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":"Dairy cows' responses to 2 separation methods after 3 months of cow-calf contact","authors":"Anina Vogt ,&nbsp;Susanne Waiblinger ,&nbsp;Rupert Palme ,&nbsp;Uta König von Borstel ,&nbsp;Kerstin Barth","doi":"10.3168/jds.2024-25293","DOIUrl":"10.3168/jds.2024-25293","url":null,"abstract":"<div><div>Weaning and separation remain among some of the biggest challenges for cow-calf contact systems, making the development of practical and low-stress separation methods mandatory for future success of these systems. This study aimed to compare behavioral and physiological responses of dairy cows to separation from their calves after 3 mo of full-time contact, with either the 2-step method (NF, 2 wks full-time contact while calves wore a nose flap, 1 wk fence-line contact before total separation, n = 18) or by gradual reduction of contact time between cow and calf (GR, 1 wk half day contact, 1 wk morning contact, 1 wk fence-line contact before total separation, n = 18). Vocalizations and searching behavior were observed on 4 d/wk from 1 wk before separation until 1 wk after total separation. During the same period, lying behavior and rumination time was automatically assessed via accelerometers and pressure sensors. Fecal and blood samples were collected twice per week from day −1 until +23 relative to separation start for analysis of fecal cortisol metabolites and the immune response. Milk yield in the parlor was continuously recorded. Statistical analysis was conducted using linear mixed effects models. We found no difference between the 2 separation methods in any of the examined behavioral and physiological response variables. However, a significant increase in vocalizations and searching behavior compared with baseline was present with both methods. Furthermore, there was a transient increase in physiological distress markers and a short-lived retention of milk yield at initiation of treatments, indicating that both methods induced distress for the cows. Descriptively, there were large interindividual differences between cows as well as a different temporal distribution in occurrence of behavioral responses, as GR cows vocalized most frequently during the week with fence-line contact and after total separation from the calf, while NF cows reacted strongest during the 2 wk while calves wore the nose flap. Milk yield was higher in NF than GR cows during the 2 wk while GR calves had time-restricted access to their dams and NF calves were prevented from suckling, but showed no difference afterward. However, similar evening milk yields of GR cows in the weeks with half-day and morning contact, indicated that the weekly reductions in contact time worked in a rather stepwise than gradual manner, which warrants further improvement of the GR method. Taken together, results showed that cows experienced distress during separation with the GR method, when implemented over 3 wk in 3 steps, as well as with the NF method, but differences between individuals were considerable.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1940-1963"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611525","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":"Comparison of the mid-infrared spectra and prediction equations developed from morning and evening milk samples from twice-a-day milked dairy cows","authors":"M. Frizzarin ,&nbsp;E. Hayes ,&nbsp;A. Casa ,&nbsp;D.P. Berry","doi":"10.3168/jds.2024-25504","DOIUrl":"10.3168/jds.2024-25504","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Mid-infrared spectroscopy is a technology used globally for quantifying the concentration of fat, protein, lactose, and other constituents in the milk samples of both individual animals and bulk tank milk. Differences in the milk components and yield of cows are known to exist between morning and evening milk; nonetheless, differences in the spectra originating from the same cow from morning and evening milkings have never been investigated. Data were obtained from 2,602 dairy cows from 7 research farms in Ireland. A total of 199,288 morning milk spectra with associated evening milk spectra produced by the same cow within 24 h were available. Postediting, spectral data were available on the same 502 wavelengths in the mid-infrared region of the electromagnetic spectrum for all milk samples. Differences between morning and evening milk spectra produced by the same cow in a 24-h period were investigated using (1) the mean and SD of the difference between morning and evening spectra absorbance values, (2) the correlation between the morning and the respective evening wavelength absorbance values, and (3) the L&lt;sub&gt;2&lt;/sub&gt; distance, all of which were quantified across stages of lactation, years, and farms. The average (SD) difference between the morning and the evening spectrum absorbance values produced by the same cow within 24 h was 0.00097 (0.008), and it was always larger than 0.055 for the wavelengths between 2,920 cm&lt;sup&gt;−1&lt;/sup&gt; and 2,947 cm&lt;sup&gt;−1&lt;/sup&gt;. The correlation between morning wavelength absorbance values and the respective evening wavelength absorbance values were all strong (i.e., &gt;0.80) in the spectral region of 1,469 cm&lt;sup&gt;−1&lt;/sup&gt; to 1,473 cm&lt;sup&gt;−1&lt;/sup&gt;; weak correlations of &lt;0.26 existed between morning and evening spectra wavelengths in the region of 1,593 cm&lt;sup&gt;−1&lt;/sup&gt; to 1,597 cm&lt;sup&gt;−1&lt;/sup&gt;. These trends in correlations generally persisted within different stages of lactation, years, and farms. Results from the L&lt;sub&gt;2&lt;/sub&gt; distance indicated that early lactation morning and evening spectra were more different from each other than when compared in late lactation; no large differences in the L&lt;sub&gt;2&lt;/sub&gt; distance across different farms and years were evident. The impact of a prediction equation developed from morning spectral data but applied to evening milk spectral data, and vice versa, was investigated. Nitrogen use efficiency (NUE) was the animal trait explored; the mean NUE (SD) in the validation dataset was 22.16 (4.86). The root mean square error for predictions developed and validated on morning spectra samples was 3.49; this increased to 3.85 for the same validation in the morning spectra when the prediction equation was developed using only evening spectra. Similarly, the root mean square error from predictions developed and validated on evening spectra samples was 3.46, which increased to 3.85 when the prediction equation was developed using only morning spectra. In conclusion, morning and","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1573-1583"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142851889","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":"Donkey milk supplementation alleviates renal fibrosis of chronic kidney disease by enhancing anti-inflammatory ability","authors":"Cui Huimin ,&nbsp;Wang Peng ,&nbsp;Chen Man ,&nbsp;Lin Hong ,&nbsp;Zhao Yuxin ,&nbsp;Pu Zhiyu ,&nbsp;Yang Jianjun","doi":"10.3168/jds.2024-25388","DOIUrl":"10.3168/jds.2024-25388","url":null,"abstract":"<div><div>Donkey milk, rich in essential nutrients, is not only able to meet the nutritional needs of patients with chronic kidney disease (CKD) according to the National Kidney Foundation's Kidney Disease Outcomes Quality Initiative Clinical Practice Guideline for Nutrition in CKD, but also has strong anti-inflammatory properties. Inflammation is the main driving force of renal fibrosis, which directly determines renal function in CKD. However, the impact of donkey milk on CKD and the underlying mechanisms remain unclear. We hypothesized that donkey milk supplementation could enhance anti-inflammatory abilities in individuals with CKD, thereby inhibiting renal fibrosis and improving renal function. Therefore, we investigated the influence of a 6-wk treatment with donkey milk on unilateral ureteral ligation–induced CKD rats. The results demonstrated that the level of miR-223-3p was decreased in the kidneys of CKD rats compared with normal rats. However, donkey milk supplementation activated miR-223-3p, thereby inhibiting the expression of inhibitor of kappa-B kinase (IKKα) and nuclear factor kappa-B (NF-κB) proteins. Consequently, the expression of inflammatory factors such as monocyte chemotactic protein-1 (<em>MCP-1</em>) and <em>IL-6</em> was suppressed, leading to reduced aggregations of macrophages in the kidney and decreased transforming growth factor β1 (TGF-β1) expression. Ultimately, renal fibrosis was inhibited, which was confirmed by decreased collagen type I α 1 (<em>COL1A1</em>) mRNA, thereby the renal function of CKD rats was improved. These results indicate that miR-223-3p may be another potential therapeutic target for CKD. Moreover, the contribution of donkey milk to alleviating the inflammatory response and renal fibrosis of CKD is obvious, indicating that donkey milk may be a new functional food for CKD patients to promote health.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1198-1210"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142851890","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":"A genomic analysis of twinning rate and its relationship with other reproductive traits in Holstein-Friesian cattle","authors":"Brian W. Kirkpatrick ,&nbsp;Donagh P. Berry","doi":"10.3168/jds.2024-25236","DOIUrl":"10.3168/jds.2024-25236","url":null,"abstract":"<div><div>Twin births in dairy cattle is generally unfavorably associated with reproductive performance and calf survival in dairy cows. Genetic selection to reduce twinning rate in dairy cattle may be desirable, provided no undesirable correlated responses in other traits exist. The current study was undertaken to characterize the genomic architecture of twinning rate in the Irish Holstein-Friesian population, and to quantify the genetic relationship of twinning with other reproductive traits and milk yield. Calving records from the years 1996 to 2022 were used together with pedigree information to generate breeding value estimates for twinning rate. Genome-wide association analyses of twinning rate, calving interval, cow survival and age at first calving were conducted using de-regressed breeding values estimates for 2,656 Holstein-Friesian sires. Full genome sequence data imputed from ∼50,000 single nucleotide polymorphisms were available for all sires. The h² of twinning rate was 0.0118 ± 0.0010. Twinning rate was very weakly genetically correlated with both milk yield (0.13) and the reproductive traits (−0.26 to 0.14). Genomic analyses detected an association with twinning rate at 31.1 Mb on BTA11 in close proximity to genes for FSH receptor and luteinizing hormone-chorionic gonadotropin receptor, supporting previous studies. The most significant SNP in this region was not associated with milk yield, indicating the potential for selection to reduce twinning rate without detrimentally affecting milk yield. Novel SNP associations with age at first calving on BTA27 and from a meta-analysis of calving interval and age at first calving on BTA29 were also identified and are candidates for future validation and study.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1686-1698"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142454790","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":"The effects of magnitude of calcium decline at the onset of lactation on serotonin dynamics and the serotonin-calcium axis","authors":"M.K. Connelly ,&nbsp;R.M. Rodney ,&nbsp;J. Kuehnl ,&nbsp;J.P.N. Andrade ,&nbsp;F. Sonnewend Andrade ,&nbsp;S. Henschel ,&nbsp;E. Block ,&nbsp;I.J. Lean ,&nbsp;L.L. Hernandez","doi":"10.3168/jds.2024-24836","DOIUrl":"10.3168/jds.2024-24836","url":null,"abstract":"<div><div>The onset of lactation is characterized by marked increases in calcium (Ca) metabolism. Recently emphasis was placed on understanding the profile and dynamics of blood Ca and serotonin in the peripartal cow in response to this change using a randomized 2 × 2 factorial design. The aims of our study were to determine (1) how a prepartum DCAD diet and the magnitude of Ca decline at the onset of lactation alter circulating blood serotonin and ionized Ca concentration dynamics in the periparturient cow, and (2) the relationship of Ca versus serotonin during the peripartal period. Thirty-two multiparous Holstein cows were blocked by parity (2 vs. &gt;2) to ensure equal parity number across the experiment, previous 305 d milk yield, and expected parturition date and randomly allocated to positive (+120 mEq/kg; +DCAD) or negative (−120 mEq/kg; −DCAD) DCAD diets from 251 d of gestation until parturition (n = 16/diet). Immediately after calving cows were continuously infused for 24 h with (1) an intravenous solution of 10% dextrose or (2) Ca gluconate (CaGlc) to maintain blood ionized Ca concentrations at 1.2 m<em>M</em> (normocalcemia), forming the following 4 treatment groups: negative DCAD and CaGlc (NCa), negative DCAD and dextrose (NDex), positive DCAD and CaGlc (PCa), and positive DCAD and dextrose (PDex; n = 8/treatment). Blood was sampled every 6 h from 102 h before parturition until 96 h postparturition. During the continuous infusion period (the 24 h immediately following parturition) cows were sampled every 30 min. Cows fed a −DCAD diet prepartum had greater circulating serotonin concentrations pre- and postpartum. Time series analyses demonstrated that the pooled mean effect size (ES) of the relationship between ionized Ca and serotonin 36 h before parturition was significantly positive (ES = 0.164) prepartum. We also observed that the overall pooled mean ES of the relationship between prepartum blood pH 24 h prior and serotonin was significantly positive (ES = 0.111); however, for individual treatment groups, relationships were identified between blood pH and serotonin 18 and 6 h before only for the NDex group. Our data suggest that serotonin is an important factor in the regulation of Ca homeostasis during the prepartal period and that the mechanism may be integrated with blood pH.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1992-2004"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142542635","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":"Usability of volatile organic compounds from exhaled breath compared with those from ruminal fluid, serum, urine, and milk to identify diet-specific metabolite profiles in lactating dairy cows","authors":"J. Eichinger ,&nbsp;A.-M. Reiche ,&nbsp;A. Münger ,&nbsp;L. Eggerschwiler ,&nbsp;G. Pimentel ,&nbsp;P. Fuchsmann ,&nbsp;K. Huber ,&nbsp;F. Dohme-Meier","doi":"10.3168/jds.2023-24579","DOIUrl":"10.3168/jds.2023-24579","url":null,"abstract":"<div><div>To investigate dietary influences on the volatilome, the volatile subcategory of the metabolome, we performed a comparative untargeted volatilome analysis of exhaled breath, ruminal fluid, serum, urine, and milk from lactating Holstein cows fed different diets. Thirty-two cows (83.3 ± 31.40 DIM, 30.6 ± 5.03 kg of milk/d) were assigned to 4 diets. The experiment lasted 16 wk. Throughout the experiment, half of the animals were fed a hay-based diet (HD; n = 16), and the other half were fed a silage-based diet (SIL; n = 16). In experimental wk 5 to 12, half of the animals in each group received the control concentrate (CON), and the other half was fed with the CON supplemented with a blend of essential oils (EXP). We hypothesized that the basal diet and the essential oils influence the volatile organic compound (VOC) profiles of the cows through potential changes in ruminal fermentation, digestion, and metabolism (hypothesis 1). Furthermore, we hypothesized that the potential effects of essential oils would have a delayed onset and a carryover effect (hypothesis 2). Every 4 experimental weeks (i.e., in wk 4, wk 8, wk 12, and wk 16), samples of exhaled breath, ruminal fluid, serum, urine, milk, and feed were collected for dynamic headspace extraction and gas chromatographic analysis of VOC in their gaseous phase. Milk yield, milk composition, BW, and feed intake were recorded regularly. Linear mixed models and multivariate and univariate data analyses were performed. The total DMI and basal diet intake was similar between cows fed HD and SIL diets. However, SIL cows consumed less of the concentrate, NDF, and water-soluble carbohydrates and more starch than HD cows. The SIL cows had a higher milk production than the HD cows. No effect was found regarding the concentrate type on feed intake or milk production. Irrespective of diet, 2,957 VOC were detected in the gaseous phase of serum; 2,771 in exhaled breath; 1,016 in urine; 1,001 in milk; and 921 in ruminal fluid. Across the experimental wk 4, 8, 12, and 16, the basal diet altered the VOC profiles of ruminal fluid, urine, and exhaled breath but not those of serum and milk. The concentrate type affected only the VOC profiles of the exhaled breath. Most diet-influenced VOC in the affected biological matrices were identified as dietary components. The experimental week influenced the VOC profiles of all matrices, especially those of exhaled breath. The VOC profile of exhaled breath strongly correlated with that of urine, followed by that of ruminal fluid, milk, and serum. This study provides the first description of diet- and time-specific VOC profiles from the biological matrices of dairy cows. The identified discriminatory VOC seem suitable as markers to discriminate between HD and SIL cows. Exhaled breath may be a promising, sensitive, and less invasive tool to follow diet- and time-related metabolic changes.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1474-1494"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611030","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 milk extracellular vesicles from Holstein Friesian and Brown Swiss heat-stressed dairy cows on bovine mammary epithelial cells","authors":"S. Castellani ,&nbsp;L. Basiricò ,&nbsp;A. Maggiolino ,&nbsp;C. Lecchi ,&nbsp;P. De Palo ,&nbsp;U. Bernabucci","doi":"10.3168/jds.2024-25133","DOIUrl":"10.3168/jds.2024-25133","url":null,"abstract":"<div><div>The increase in ambient temperature is responsible for a behavioral, physiological, and metabolic responses known as heat stress, which affects dairy cows' general well-being, health, reproduction, and productivity. Focusing on the functioning of the mammary gland, attention has been recently paid to a new method of cell-cell communication mediated by extracellular vesicles, which with their cargo can affect the target cells' phenotypic traits, behavior, and biological functions. This study investigated whether the small extracellular vesicles (sEV) isolated from milk of heat-stressed Holstein Friesian (H) and Brown Swiss (B) cows affect the cellular response of a bovine mammary epithelial cell line (BME-UV1). To this purpose, 8 mid lactation cows, 4 of each breed fed the same diet and kept in the same barn, which experienced the same hyperthermia during a natural heat wave, were chosen to collect 2 milk different samples: under thermoneutrality (TN, d1) and under heat stress (HS, d 8) conditions. The sEV were isolated from skim milk samples through differential centrifugations, characterized for size and concentration by nanoparticle tracking analysis. Integrity of the milk sEV membranes was evaluated by transmission electron microscopy and presence of EV markers through western blotting. Then BME-UV1 cells were incubated for 24 h with different pooled milk sEVs (H-TN, H-HS, B-TN, B-HS). Cell viability and apoptosis assay, reactive oxygen species production, and mRNA expression of heat shock proteins and antioxidant genes by reverse transcription and real time PCR were determined. In vivo results showed an increase in rectal temperature and respiration rate, a reduction in milk yield both for H and B dairy cows, with a lowest decrease observed in B cows compared with H cows. In vitro results of BME-UV1 cells treated with milk sEV H-HS and B-HS showed an alteration of the cell viability and metabolic activity, by reducing or increasing reactive oxygen species accumulation, and suppressing or increasing the expression of stress-associated genes thereby modulating the response of BME-UV1 according to the animals' thermal condition and the breed. These findings indicated that the small vesicles of Brown milk triggered cellular defense against heat stress, supporting the Brown Swiss breed's thermotolerance.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1978-1991"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811728","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":"From posts to practice: Instagram's role in veterinary dairy cow nutrition education—How does the audience interact and apply knowledge? A survey study","authors":"M. Lamanna ,&nbsp;E. Muca ,&nbsp;G. Buonaiuto ,&nbsp;A. Formigoni ,&nbsp;D. Cavallini","doi":"10.3168/jds.2024-25347","DOIUrl":"10.3168/jds.2024-25347","url":null,"abstract":"<div><div>This study evaluates Instagram's efficacy as an educational tool in veterinary sciences, focusing on dairy cow nutrition and management. Using the Instagram account “Stalla Didattica Unibo,” established in December 2020, a survey was conducted with 102 respondents, primarily consisting of university students (44.12%). The respondents were divided into 2 major groups: students and the general population, with the latter comprising professionals and others not currently in educational programs. In the overall population, the age group of 25 to 34 yr accounted for 51%, but among students, it was 73.3%. In terms of gender distribution, there was a female majority in the general population (59.8%) and a male majority among students (73.3%). Most responders were from Italy, with Emilia-Romagna contributing significantly. Engagement was measured not only by the length of time participants followed the account but also by active interactions such as likes, comments, and shares. Among the total population, 47.1% had followed the page for over a year, compared with 37.8% of students. Importantly, engagement metrics showed active participation, with a majority reporting improved knowledge (75.6% of the total population and 74.5% of students) and practical application of content (64.4% of the total population and 67.6% of students). Content preferences varied, with the general population favoring quizzes (33.3%) and stories (17.8%), whereas students showed a stronger preference for standard posts (36.3%). Impact was defined as the perceived influence of the Instagram content on the respondents' learning and professional practices, with 46.7% of the total population and 52.9% of students agreeing or strongly agreeing that the page had a positive impact on their knowledge and practical skills. Furthermore, 84.3% of students and 77.8% of the total population stated they would recommend the page to others, underscoring the account's effectiveness as a digital educational tool. The study highlights Instagram's potential to enhance veterinary education and suggests further research to explore the broader application of these strategies across different educational contexts and platforms.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1659-1671"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811781","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}