Journal of Dairy Science最新文献

{"title":"Bioactive milk-derived nutrient MFG-E8 ameliorates skeletal muscle atrophy induced by mitochondria damage in aging rats via activating the MAPK/ERK signaling pathway","authors":"Kaifang Guan ,&nbsp;Xiaolin Liu ,&nbsp;Weihong Lu ,&nbsp;Yuhao Mao ,&nbsp;Yirong Mao ,&nbsp;Ying Ma ,&nbsp;Rongchu Wang ,&nbsp;Qiming Li","doi":"10.3168/jds.2024-25532","DOIUrl":"10.3168/jds.2024-25532","url":null,"abstract":"<div><div>Sarcopenia is the age-related loss of muscle and fiber number and decreased regenerative capacity with increased abundance of reactive oxygen species levels and electron transport chain abnormalities. The aim of this study was to investigate the antisarcopenia effect of MFG-E8 in alleviating skeletal muscle dysfunction induced by D-galactose, and reveal the mechanism promoting myoblast cell proliferation and mediating the cell cycle. This in vivo experiment showed that MFG-E8 can improve the antioxidant status and increase soleus muscle mass (35.61%) and fiber diameter (39.72%) in the aging rats. The western blot assay preliminarily proved that increased ERK phosphorylation determines the repairment of injured skeletal muscle, but not JNK and p38. In vitro experiments further verified that MFG-E8 can increase the number of mitochondria, cell vitality, cell density, and reduce apoptosis rate. Flow cytometry and quantitative real-time PCR proved that MFG-E8 promoted cell proliferation by upregulating mRNA expression of cyclin D1, cyclin E1, CDK, and downregulating mRNA expression of p21 and p27, thereby increasing the S and G₂/M phase and decreasing the G₀/G₁ phase. Molecular level further proved that MFG-E8 mediated cell cycle and promoted cell proliferation by activating the MAPK/ERK signaling pathway.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1182-1197"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142851888","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":"Associations between milk infrared-predicted plasma biomarkers of stress resilience and fertility in dairy cattle: Insights for enhancing breeding programs and herd management","authors":"Alessio Cecchinato ,&nbsp;Hugo Toledo-Alvarado ,&nbsp;Lucio Flavio Macedo Mota ,&nbsp;Vittoria Bisutti ,&nbsp;Erminio Trevisi ,&nbsp;Riccardo Negrini ,&nbsp;Sara Pegolo ,&nbsp;Stefano Schiavon ,&nbsp;Luigi Gallo ,&nbsp;Giovanni Bittante ,&nbsp;Diana Giannuzzi","doi":"10.3168/jds.2024-25461","DOIUrl":"10.3168/jds.2024-25461","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Fertility is a crucial aspect of dairy herd efficiency and sustainability. Among factors influencing fertility in dairy cattle, metabolic stress and systemic inflammation of animals are of main relevance, especially in the postpartum stage when ovarian activity begins and cows are inseminated. Our study aimed to infer the associations between milk infrared-predicted blood biomarkers of stress resilience and fertility traits, namely the interval from calving to first service (iCF), days open (DO), and the pregnancy rate at first service (PRF) in a multibreed population of 89,097 dairy cows. The blood metabolites (15 blood biomarkers related to hepatic damage and function, oxidative stress, inflammation, and innate immunity) were predicted using milk Fourier-transform mid-infrared (MIR) spectroscopy. A gradient boosting machine approach with leave-one-batch-out cross-validation (R&lt;sup&gt;2&lt;/sup&gt; range from 0.45 to 0.82) was implemented to an independent calibration database of 1,367 lactating cows reared in 5 herds. Calibration equations were then applied to a population database of 1,799,186 MIR milk spectral data, that were then merged with fertility data collected by the Breeders Federation of Alto Adige (Bolzano province, Italy) generating a final database of 285,145 records. The 2 databases were merged according to the milk test day (and thus, the MIR spectrum) closest to the date of insemination. The interval fertility traits were fitted as the hazard of either receiving the first service after calving at time &lt;em&gt;t&lt;/em&gt; for iCF or becoming pregnant after calving at time &lt;em&gt;t&lt;/em&gt; for DO in a Cox proportional-hazards model. Statistical analyses were performed including in the model the number of lactations, year of calving, and herd as fixed effects. The independent effect of the MIR-based predictions of metabolites was also included with each metabolite evaluated separately and discretized into 7 levels based on percentiles. Pregnancy rate at first service, however, was analyzed using logistic regression and the same explanatory variables. The metabolites linked to liver function and damage, such as aspartate aminotransferase, total bilirubin, and alkaline phosphatase, had a relevant influence on iCF and DO in terms of the hazard ratio (HR). Relevant results were also obtained for the biomarkers related to oxidative stress, inflammation, and innate immunity. Specifically, increasing levels of ceruloplasmin, total reactive oxygen metabolites, and advanced oxidation protein products resulted in a relevant decrease in the HR of cows becoming pregnant. The logistic regression analysis did not reveal any significant effect of the aforementioned biomarkers on PRF, indicating that the effects of the stress response mainly concern the resumption of the ovarian cycle after calving. The results for the associations of the predicted biomarkers of the stress response with iCF and DO were consistent with expected physiological patterns. In conclu","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 2005-2022"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611494","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":"Changes in photoperiod during the dry period impact colostrum production in Holstein and Jersey cows","authors":"K.J. Alward ,&nbsp;A.J. Duncan ,&nbsp;A.D. Ealy ,&nbsp;G.E. Dahl ,&nbsp;C.S. Petersson-Wolfe ,&nbsp;R.R. Cockrum","doi":"10.3168/jds.2024-25415","DOIUrl":"10.3168/jds.2024-25415","url":null,"abstract":"<div><div>Multiparous Holstein cows exposed to short-day photoperiod (SDPP) of 8 h of light per day during their dry period produced up to 3.2 kg more milk per day compared with cows exposed to long-day photoperiod (LDPP) of 16 h of light per day; it is unknown if a similar response would be observed for Jersey cow milk production. The objective of this study was to determine the effect of photoperiod during the dry period on subsequent colostrum and milk production in Holstein and Jersey cattle. Holstein and Jersey cows (n = 33) were dried off 60 d before their due date and randomly assigned to SDPP (Holstein, n = 9; Jersey, n = 8) or LDPP (Holstein, n = 8; Jersey, n = 8) until calving. Cows were weighed at the time of enrollment (d 0) and were housed in an enclosed barn at 20°C and exposed to 250 to 450 lx during periods of light and &lt;10 lx during periods of darkness. At calving, colostrum volume was weighed and tested for relative protein concentration with a Brix refractometer and a sample was collected for component analysis (fat, protein, lactose, SNF) via infrared spectroscopy, as well as IgA, IgG, IgG1, IgM, lactoferrin, and SCS analysis. After calving, cows were returned to the freestall barn and exposed to ambient photoperiod and temperature. Milk production data were collected for 15 wk postcalving. Data were analyzed using PROC MIXED in SAS (SAS 9.4; SAS Institute Inc., Cary, NC) with treatment, breed, and d 0 weight as fixed effects. PROC MIXED with repeated measures was used to evaluate the relationship of day length and breed with mature milk volume, fat, and protein production. Random effects included replicate, lactation number, genetic inbreeding percentage, previous lactation mature equivalent 305-d protein production, and calf sex. For colostrum, Brix score, colostral protein, fat, IgA, and IgM were increased in Jersey cows compared with Holstein cows. Total colostrum weight, SNF, lactose, lactoferrin, IgG, IgG1, and SCS did not differ by breed or treatment. Postcalving, ECM production was increased in Holstein cows compared with Jersey cows but unaffected by photoperiod treatment. Conversely, milk protein percentage was increased for Jersey cows relative to Holstein cows but was unaffected by photoperiod treatment. Milk fat increased in LDPP Holstein cows compared with SDPP Jersey cows during the first week of lactation, which is likely due to the transition from colostrum to mature milk production. Overall, photoperiod did not affect colostrum production, but differences by breed were detected. Photoperiod during the dry period did not affect mature milk production or protein, but milk fat percentage was affected by photoperiod × breed. Therefore, altered lighting during the dry period does not unfavorably affect colostrum or milk production in Jersey or Holstein cows.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1672-1685"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811578","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":"INTERPRETIVE SUMMARIES, FEBRUARY 2025","authors":"","doi":"10.1016/S0022-0302(25)00029-3","DOIUrl":"10.1016/S0022-0302(25)00029-3","url":null,"abstract":"","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages vii-xv"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102093","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":"Association of genomic predictions for fertility traits with reproductive outcomes in dairy cows under 2 estrus detection and timed artificial insemination programs","authors":"D.B. Melo ,&nbsp;R.G.S. Bruno ,&nbsp;R.S. Bisinotto ,&nbsp;F.S. Lima","doi":"10.3168/jds.2024-25499","DOIUrl":"10.3168/jds.2024-25499","url":null,"abstract":"<div><div>Genomic prediction of daughter pregnancy rate (GDPR) and cow conception rate (GCCR) are fertility traits developed to help improve selection for reproductive performance. Although these traits overlap, their denominator can vary, and programs with different strategies combining estrus detection (ED) and timed AI might experience different associations with these traits (e.g., shorter interval for first service for high GDPR quartiles, but not for GCCR). The objectives were to assess days from calving to first service (TP1), AI at ED (AIE), pregnancy at the first service (P1), pregnancy loss for the first service (PL), and number of services to conception (NSFC) in 2 reproductive programs (RepP) combining variable ED length and timed AI (TAI) and their relationship with GDPR and GCCR. Holstein cows from a single farm were randomly allocated to 2 different programs, the short RepP (n = 982) or long RepP (n = 942). In the short RepP, cows were enrolled in a Presynch-Ovsynch (PGF_2α: 36 ± 3 and 50 ± 3 DIM) followed by ED and AI from 50 ± 3 to 62 ± 3 DIM. Cows not detected in estrus underwent in the Ovsynch (GnRH: 62 ± 3, PGF_2α: 69 ± 3, GnRH: 71 ± 3 and TAI :72 ± 3 DIM). In the long RepP, cows received a PGF_2α at 50 ± 3 DIM followed by AI at ED up to 81 ± 3 DIM. Cows with no ED were enrolled in an Ovsynch (GnRH:82 ± 3, PGF_2α:89 ± 3, GnRH:91 ± 3 and TAI:92 ± 3 DIM). Cows were categorized into quartiles (Q1 to Q4) considering their GDPR (qGDPR) and GCCR (qGCCR). Statistical analyses included logistic regression used for AIE, P1, and PL; Poisson regression for the NSFC; and linear regression for TP1. Models included AIE, P1, PL, NSFC, and TP1 as dependent variables, with RepP and qGDPR for GDPR and RepP and qGCCR for GCCR as independent variables. Time to pregnancy was analyzed using Cox's proportional hazard model. The short RepP had a shorter TP1 (short = 64.3 vs. long = 72.1) and fewer NSFC than the long RepP (short = 2.9 vs. long = 3.1). The long RepP had a higher AIE (short = 45.2% vs. long = 73.2%). The P1 tended to be greater in the short than the long RepP (short = 33.7% vs. long = 30.0%). Cows in Q4 (GDPR and GCCR) had lower TP1 and NSFC, greater AIE and P1 compared with the lowest quartiles (Q1). Interactions between RepP and GDPR were present for TP1, AIE, and P1, but no interactions were observed between RepP and GCCR. The short program had a shorter interval from calving to pregnancy than the long program. Cows in the highest quartiles for GDPR and GCCR had shorter intervals from calving to pregnancy and higher pregnancy hazards than the lowest quartiles. The current study revealed that cows enrolled in long RepP that relied on longer ED intervals had lower reproductive outcomes than short RepP cows, and cows ranked in the highest GDPR and GCCR quartile for most responses had better outcomes independent of the RepP used.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 2060-2069"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811574","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":"Impact of training dairy farm personnel on milking routine compliance, udder health, and milk quality","authors":"Zelmar Rodriguez ,&nbsp;Mario Lopez-Benavides ,&nbsp;Marianna B. Gentilini ,&nbsp;Pamela L. Ruegg","doi":"10.3168/jds.2024-25609","DOIUrl":"10.3168/jds.2024-25609","url":null,"abstract":"<div><div>Among various farm procedures, an appropriate milking routine is crucial for reducing mastitis and enhancing milk safety and quality. However, inadequate compliance with milking routines remains a primary factor contributing to variability of milk quality among herds. Training farm workers is essential for ensuring compliance with milking routines, which directly affects milk quality and udder health. In this study, we aimed to assess the impact of a training session on dairy farm workers' understanding of the milking routine, behavioral changes during milking, and subsequent effects on milk quality and udder health. Farm workers (n = 112) from 16 commercial dairy farms in Michigan and Ohio participated in the project. The training session was delivered using an active learning approach prioritizing group discussions, and focused on the pathogenesis, identification, and risk factors for mastitis, as well as the rationale and importance of each step in the milking routine. Pre- and post-training evaluations were conducted to measure changes in knowledge, parlor evaluations were performed to determine behavioral changes, and data from clinical mastitis cases and bulk tank SCC were used to estimate udder health and milk quality. Segmented and linear mixed regression analyses were used to assess the impact of the training intervention. Participants were mostly milking technicians (61.1%) with 70% of them having less than 1 yr of experience and a median tenure in their jobs of 9 mo. Knowledge of the milking routine increased from 49.3% to 67.6% of correct answers after training. Based on parlor evaluations, the premilking disinfectant contact time increased by 9 s per cow. The percentage of milkings with inadequate preparation time decreased from 69% (before training) to 48% (after training). The proportion of insufficient teat coverage during postmilking disinfection decreased from 9.8% (77 out of 782) before training to 5.9% (34 out of 572) after training. We observed a significant increase in clinical mastitis cases during the immediate week after the training. Additionally, the upward trend in bulk tank SCC was halted. Our results suggest an improvement in overall mastitis identification and milk quality, underscoring the importance of targeted training programs for farm workers in improving milking routine compliance, enhancing milk quality, and promoting better udder health.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1615-1624"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Milk adulteration identification using hyperspectral imaging and machine learning","authors":"Muhammad Aqeel ,&nbsp;Ahmed Sohaib ,&nbsp;Muhammad Iqbal ,&nbsp;Syed Sajid Ullah","doi":"10.3168/jds.2024-25635","DOIUrl":"10.3168/jds.2024-25635","url":null,"abstract":"<div><div>Milk adulteration poses a global concern, with developing countries facing higher risks due to unsatisfactory monitoring systems and policies. Surprisingly, this common issue has often been overlooked in many countries. Contrary to popular belief, adulterants in milk can result in severe health risks, potentially leading to fatal diseases. Detecting and categorizing milk adulteration is crucial for consumer safety and the dairy industry. This research is divided into 2 breakthroughs, destructive and nondestructive methods. In the destructive method, the Lactoscan system was used for qualitative analysis: SNF, density, fat, lactose, conductivity, solids, protein, temperature, and pH level. The research also examines nondistractive hyperspectral imaging (HSI) through HSI Specim Fx-10 (397–1,003 nm; Specim, Spectral Imaging Ltd., Oulu, Finland) analysis to detect various phases of milk adulteration for accurate and user-friendly imaging-based adulterant detection and categorization. Preprocessing involves radiometric correction, image resizing, region of interest selection for feature extraction, and empirical line method to calculate spectral reflectance signature. Machine learning techniques (logistic regression, decision tree, support vector machine, and linear discriminant analysis [LDA]), are employed, with LDA excelling in adulteration identification by learning the spectral signatures. These algorithms are trained and validated using a developed milk adulteration dataset. Training, testing, and validation accuracy, precision, recall, <em>F</em>₁ score, kappa, and Matthew's correlation coefficient metrics showcase the effectiveness of the proposed pipeline, outclassing numerous state-of-the-art approaches with a validation accuracy of 100%. In conclusion, this study established a multiclass model capable of detecting milk adulterant behavior, showing significant practical application for milk quality assessment.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1301-1314"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611460","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 ruminal short-chain fatty acid concentration and pH on histology, hematology, and inflammation in cannulated Holstein dairy calves","authors":"A.R. Wolfe,&nbsp;M.H.P.M. Narciso,&nbsp;R.R.E. Uwiera,&nbsp;A.H. Laarman","doi":"10.3168/jds.2024-25589","DOIUrl":"10.3168/jds.2024-25589","url":null,"abstract":"<div><div>Optimizing rumen development is key to preparing calves for weaning; however, it is unclear what effect rumen development has on calf health via ruminal infusion. This study investigated the effects of ruminal short-chain fatty acid (SCFA) concentrations and pH on hematology, gut morphology, and inflammation of liver and rumen tissues in dairy calves. Holstein calves (n = 32) had the rumen cannulated within the first week of life and at wk 2 were blocked by BW and randomly assigned in a 2 × 2 factorial arrangement of treatments. The treatments included 2 different SCFA concentrations (10 vs. 285 m<em>M</em>) and pH levels (5.2 vs. 6.2), yielding 4 treatment groups: low SCFA, low pH (LS-LP); low SCFA, high pH (LS-HP); high SCFA, low pH (HS-LP); and high SCFA, high pH (HS-HP). On wk 3, 5, and 7, calves underwent a 4-h reticulorumen wash procedure with a physiological buffer containing the various treatments. Blood samples were collected weekly after feeding. Rumen biopsies were taken after each infusion, and liver and rumen samples were harvested at necropsy at wk 7. Data were analyzed with repeated measures, using week, SCFA, and pH as fixed effects. Low rumen pH increased respiration rate, but no other changes in clinical parameters were observed. No differences were detected in red blood cells or platelet numbers. Total white blood cell numbers decreased in the LS-LP group from wk 5 to 7 but increased in the HS-LP group along with hemoglobin and the hematocrit during the same period. Cortisol and BHB levels were unchanged by treatment or time, whereas haptoglobin decreased over time regardless of treatment. Calf liver morphology was unaffected by treatment; ruminal tissue changes associated with epithelial cell sloughing tended to increase with low SCFA, and mucosal eosinophil infiltration increased with high SCFA. Gene expression was unchanged by treatment in both rumen (barrier function and inflammation) and liver (inflammation). Overall, the data demonstrate that stress and inflammatory responses can be affected by changing rumen environments. Notably, these changes are transient as values returned to pretreatment baseline levels after a period as short as a week.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 2070-2082"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142811775","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":"Profitability of Swedish Red-and-White × Holstein crossbred cows compared with purebred Holstein cows","authors":"D.F. Pipino ,&nbsp;N. López-Villalobos ,&nbsp;R.E. Hickson ,&nbsp;V.E. Cabrera ,&nbsp;M. Balzarini ,&nbsp;M. Piccardi","doi":"10.3168/jds.2024-25260","DOIUrl":"10.3168/jds.2024-25260","url":null,"abstract":"<div><div>An economic analysis was performed using a bioeconomic simulation model based on production, reproduction, and longevity indicators to compare the profitability (net income per cow) of Swedish Red-and-White × Holstein (S×H) cows and pure Holstein (HOL) cows in commercial dairy farms of the center-south of Córdoba province, Argentina. The reproductive events analyzed in the model were pregnancy, calving, and abortion. The longevity events were culling, sale, and death. The lactation curve for each cow was modeled with a lactation function. Estimations were made for the first, second, and third and later lactations. Income sources were from milk, culled cows, and calves. Costs were from feeding, reproductive program, and replacement heifers. The reproductive cost of a HOL cow per year was greater than that of a S×H crossbred cow (US$6.30). The replacement costs were also higher in pure HOL cows than in S×H cows (US$67.80). The revenues from the sale of calves (US$12.10) and milk production minus the feed cost (US$8.20) were greater for S×H cows than HOL cows. Hence, the S×H cows generated a greater total profit (US$94.40) per cow per year than HOL cows. The present results show that in the studied production systems, S×H crossbred cows are more profitable than HOL cows.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1602-1614"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611006","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":"Production and metabolic responses of Montbéliarde and Holstein cows during the periparturient period and a sequential feed-restriction challenge","authors":"J.A.A. Pires,&nbsp;A. De La Torre,&nbsp;L. Barreto-Mendes,&nbsp;I. Cassar-Malek,&nbsp;I. Ortigues-Marty,&nbsp;F. Blanc","doi":"10.3168/jds.2024-25488","DOIUrl":"10.3168/jds.2024-25488","url":null,"abstract":"<div><div>Our objective was to compare the production and metabolic responses of 22 Montbéliarde (MONT) and 18 Holstein (HOLS) multiparous cows during the periparturient period, and during a sequential nutritional challenge (SNC), consisting of 4 successive induced short feed restrictions each separated by a refeeding period, to explore breed differences in robustness (ability to maintain lactation function during successive challenges) and resilience (ability to recover after each challenge). Cows were studied from 4 wk before expected calving until 158 ± 9 DIM (mean ± SD). Milk and ECM yields were greater in HOLS than in MONT during both the early- (i.e., from calving to wk 10) and mid-lactation (i.e., from wk 18 to 22) periods, whereas BCS was greater in MONT than HOLS. During early lactation, energy balance was lower (5 vs. 16 MJ/d) and plasma NEFA (270 vs. 163 µ<em>M</em>) were greater for HOLS than MONT, respectively. Cows in third-and-greater lactation secreted more ECM, and had delayed resumption of luteal activity compared with second-lactation cows. The SNC started at 87 ± 9 DIM and consisted of a sequence of four 4-d periods of feed restriction (FR), during which feed allowance was calculated to meet 50% of individual energy requirements (FR1, FR2, FR3, FR4), each of them being followed by an ad libitum intake period. Cows were allowed 10 d of ad libitum intake between FR1 and FR2 to study the recovery and compare it with the recovery following FR4, and 3 d of ad libitum intake between FR2, FR3, and FR4 to study responses to repeated FR. Feed allowance met 59% to 67% of energy requirements during FR1 through FR4, as milk secretion decreased with successive FR. Breed differences in milk secretion persisted throughout the nutritional challenges, but were more pronounced during the first 2 FR: Uncorrected milk yield was greater for HOLS throughout the entire SNC, whereas ECM and plasma NEFA concentrations and milk fat yield were greater for HOLS than MONT during FR1 and FR2, but not FR3 and FR4, suggesting a reduced ability of HOLS to mobilize and transfer fatty acids into milk with successive FR, and indicating altered robustness of HOLS to maintain high milk yield. Resilience for ECM yield did not differ between breeds. Cows were able to respond to and recover from the SNC by decreasing milk secretion during FR, undergoing acute metabolic adaptations to support lactation, and recovering DMI during each refeeding period. Cow rankings for ECM yield were maintained consistently from early lactation throughout the SNC periods (r_s = 0.59 to 0.90), suggesting that dairy potential was a major driver of responses during the SNC for both HOLS and MONT.</div></div>","PeriodicalId":354,"journal":{"name":"Journal of Dairy Science","volume":"108 2","pages":"Pages 1495-1508"},"PeriodicalIF":3.7,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142611003","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}