JDS communications最新文献

{"title":"Carryover effects of 4 daily rumen drenches of maize gluten meal and rumen-protected essential amino acids initiated immediately after calving","authors":"C.K. Reynolds ,&nbsp;L.A. Crompton ,&nbsp;A.K. Jones ,&nbsp;C.G. Bartram","doi":"10.3168/jdsc.2024-0689","DOIUrl":"10.3168/jdsc.2024-0689","url":null,"abstract":"<div><div>The objective was to determine the effects of a daily rumen drench of maize gluten meal, as a source of RUP, and rumen-protected Met, Lys, and His for the first 4 d of lactation on DMI and milk production and composition of dairy cows during their first 12 wk of lactation. Twenty multiparous Holstein cows were randomly assigned at calving to a control rumen drench of 30 L of warm water or a 30-L aqueous suspension of maize gluten meal and rumen-protected Met, Lys, and His calculated to provide Met, Lys, His, and Leu for absorption equal to their amounts in 600 g of casein. Cows received their first drench within 8 h of calving and then again 24, 48, and 72 h later. Cows were fed a TMR for ad libitum consumption and at 7 DIM cows were moved from calving boxes to a cubicle yard, and measurements of daily DMI and milk yield and weekly milk composition, BW, and BCS were obtained through wk 12 postpartum. A blood plasma sample obtained at 7 DIM was analyzed for metabolite, protein, and albumin concentration. There was no effect of treatment on DMI or milk yield, but milk fat concentration was higher and milk protein concentration tended to be higher for treated cows during wk 2 to 12. While BCS was not affected, treated cows gained BW over the course of the study (+32 kg), whereas control cows maintained a similar BW (−3 kg). Plasma metabolite and protein concentrations were not affected by treatment. Four daily rumen doses of supplemental RUP and rumen-protected EAA, initiated within hours of calving, had sustained positive effects on milk fat and protein concentration and BW of lactating Holstein cows, suggesting homeorhetic effects that warrant further investigation.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 324-328"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895135","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Association between milk pump type and free fatty acid concentrations on dairy farms with automated milking systems","authors":"Hannah M. Woodhouse ,&nbsp;Stephen J. LeBlanc ,&nbsp;Trevor J. DeVries ,&nbsp;Karen J. Hand ,&nbsp;David F. Kelton","doi":"10.3168/jdsc.2024-0666","DOIUrl":"10.3168/jdsc.2024-0666","url":null,"abstract":"<div><div>High levels of free fatty acids (FFA) in milk (≥1.20 mmol FFA/100 g of fat) indicate excessive milk fat breakdown and compromise milk quality. Automated milking systems (AMS) have become more common in the dairy industry, but questions about their effect on milk quality, including FFA, remain. On average, AMS-milked herds have greater FFA levels in bulk tank milk than parlor-milked herds. The difference in milk pump type between some AMS and parlor systems may be a contributing factor. The objective of this study was to investigate whether a positive displacement milk pump (PDMP) would be associated with greater FFA when compared with a centrifugal milk pump (CMP) on AMS farms. We hypothesized that a PDMP would be associated with greater FFA levels because of the potential impact of high flow rates on milk fat globules. We conducted an observational pilot study using farm and milk quality data collected from Ontario, Canada, AMS herd visits. Monthly average milk composition data surrounding the farm visit date were obtained from the Dairy Farmers of Ontario and included FFA concentration, milk fat (% weighted volume), milk protein (% weighted volume), and milk shipment volume (L). A linear regression analysis was conducted with monthly average FFA as the outcome and pump type as the explanatory variable of interest, with other factors identified in previous research to be associated with increased FFA accounted for in the model. One hundred twenty-one AMS herds were visited between 2019 and 2021, with an average (± SD) monthly FFA of 0.86 ± 0.18 mmol/100 g of fat. Seventy-four farms (61%) had a PDMP, and the average FFA level was 0.88 mmol FFA/100 g of fat, which was above the provincial industry average and greater than AMS farms with a CMP. The results suggest that FFA may be slightly greater on AMS farms with PDMP (β = 0.04 mmol FFA/100 g milk fat, 95% CI −0.02 to 0.10), but the difference was not statistically significant and is small compared with other previously identified FFA factors. However, this could be due to a small sample size and few study farms with high FFA levels.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 309-312"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Beyond immunoglobulin G: Dissecting the role of colostrum in programming early immune function in calves*","authors":"L. Rostoll-Cangiano ,&nbsp;M. Cid de la Paz ,&nbsp;J.F. Pierre","doi":"10.3168/jdsc.2024-0733","DOIUrl":"10.3168/jdsc.2024-0733","url":null,"abstract":"<div><div>Adequate colostrum intake is essential for neonatal calf health and development, not only reducing disease incidence but also promoting accelerated growth, earlier reproductive maturity, improved first-lactation milk yields, and lower culling rates. Although these advantages might be partly attributed to antibody-mediated disease prevention, emerging evidence highlights the critical role of colostrum's bioactive components in programming postnatal development. Colostrum's nutrient and bioactive composition is uniquely tailored to meet the developmental needs of newborn calves. Compared with mature milk, colostrum contains higher concentrations of proteins, fats, vitamins, and minerals, along with an array of growth factors and bioactive molecules that exert a foundational influence on the adaptation to extrauterine life. A deeper understanding of how these colostrum bioactive components collectively influence calf health is important to improve colostrum management and pave the way for refined nutritional and care strategies to support calves during this critical developmental period. In this review, we explore the multifaceted role of bovine colostrum beyond transfer of passive immunity, focusing on its influence in modulating early microbial encounters and guiding neonatal immune development.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 474-478"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of different processing methods on anti-trypsin activity in bovine colostrum","authors":"Lukas Trzebiatowski ,&nbsp;Plamen Georgiev ,&nbsp;Kathrin Büttner ,&nbsp;Axel Wehrend","doi":"10.3168/jdsc.2024-0678","DOIUrl":"10.3168/jdsc.2024-0678","url":null,"abstract":"<div><div>Colostrum is important for supplying the bovine neonate with nutrients, bioactive substances, and immunoglobulins to acquire passive immunity. Trypsin inhibitory activity represents a general characteristic of the first bovine colostrum. It is assumed that the anti-trypsin activity serves to protect bioactive molecules in the colostrum from being digested by the calf. The objectives of the study were to establish a test to determine anti-trypsin activity and test the hypothesis that freezing, acidification, and heat treatment alter anti-trypsin activity compared with untreated bovine colostrum. A photometric assay was established to determine anti-trypsin activity. The activity was expressed in milligrams of inhibited trypsin per milliliter of colostrum. Anti-trypsin activity was measured in untreated colostrum, frozen colostrum (−20°C for 24 h), colostrum acidified using 10% formic acid in a way that it was present as 1% in the sample, and colostrum heat treated according to 2 different protocols (60°C for 60 min and 63.5°C for 30 min). In our study, trypsin inhibition in 40 untreated colostrum samples (0.80 mg/mL, SEM 0.03) corresponded to that observed in frozen colostrum samples (0.79 mg/mL, SEM 0.03). In these first analyzed 40 and 59 extra samples (in total 99 samples), the anti-trypsin activity of frozen colostrum (0.85 mg/mL, SEM 0.01) was compared with colostrum subjected to acidification (0.84 mg/mL, SEM 0.01), heat treatment at 60°C for 60 min (0.65 mg/mL, SEM 0.02), and heat treatment at 63.5°C for 30 min (0.61 mg/mL, SEM 0.02). Acidification did not significantly affect trypsin inhibition. Both heat treatment protocols significantly reduced anti-trypsin activity. In the future, when investigating the effects of postharvest storage and processing on bovine colostrum, the influence on anti-trypsin activity should be evaluated in addition to the effects on immunoglobulins and other components.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 411-415"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of dietary rumen-protected choline supplementation on genome-wide DNA methylation in mammary tissue from postpartum dairy cows","authors":"A. Celemin Sarmiento ,&nbsp;B.J. Bradford ,&nbsp;L.K. Mamedova ,&nbsp;G. Zhou ,&nbsp;K.A. Estes ,&nbsp;T.H. Swartz","doi":"10.3168/jdsc.2024-0697","DOIUrl":"10.3168/jdsc.2024-0697","url":null,"abstract":"<div><div>Choline is a methyl donor that may influence DNA methylation, gene expression, and cellular processes. Past studies have found an increase in milk yield when periparturient dairy cows were supplemented with dietary rumen-protected choline (RPC); however, the mechanism behind this response is unknown. Therefore, the objective of this study was to assess the effects of dietary RPC supplementation on mammary genome-wide DNA methylation. Parous Holstein cows were blocked by calving month and then randomly assigned within block to receive either 30 g/d of RPC (13.6 g/d of choline ions; CHOL30, n = 21) or no RPC (CON, n = 19) as a top-dress, starting 24 d before expected calving until 21 d postpartum. Mammary tissue was collected at d 17 postpartum and DNA was isolated. A subset of samples (n = 6 per group) was randomly selected and submitted for whole-genome bisulfite sequencing. Differentially methylated cytosines (DMC), regions, and genes (DMG) were determined using the ‘genomation’ R package. The cut-off values were set at false discovery rate–adjusted <em>P</em>-value (q-value) &lt;0.05 and absolute methylation difference &gt;10%. There were 456 DMC by RPC; 241 were hypermethylated and 215 were hypomethylated in mammary tissue from CHOL30 cows as compared with CON. These DMC mapped to 109 genes, of which 51 genes had at least one hypomethylated CpG (cytosine-phosphate-guanine) site and 58 genes had at least one hypermethylated CpG site. The REACTOME pathway analysis did not identify any significantly enriched pathways with 3 or more DMG. Several genes relevant to our research question containing at least one hypermethylated CpG site included DNA polymerase α 1, catalytic subunit (<em>POLA1</em>), DNA primase subunit 2 (<em>PRIM2</em>), thrombospondin 2 (<em>THBS2</em>), and sarcosine dehydrogenase (<em>SARDH</em>). Similarly, a few genes relevant to our research question containing at least one hypomethylated CpG site included methylmalonyl-CoA mutase (<em>MMUT</em>), isocitrate dehydrogenase [NAD(+)] 3 catalytic subunit α (<em>IDH3A</em>), and pannexin 1 (<em>PANX1</em>). Our data suggest that dietary RPC supplementation alters DNA methylation in the mammary gland, potentially enhancing cellular proliferation (<em>POLA1</em> and <em>PRIM2</em>) and metabolism (<em>MMUT</em> and <em>IDH3A</em>). Nevertheless, the vast majority (95.6%) of the DMC were found in the intergenic regions, and very rarely found on the more critical regulatory elements such as the promoter regions, suggesting that dietary RPC supplementation may not exert a concerted hypomethylation or hypermethylation of genes in mammary tissue. Future studies are needed to determine if methylation status of these genes affects cellular phenotype and function in the mammary gland as a potential mechanism behind the milk production responses due to dietary RPC supplementation.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 333-338"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reanalysis of 2 metritis studies demonstrates different patterns of postpartum uterine infection for primiparous versus multiparous cows","authors":"J.C.C. Silva ,&nbsp;M.C. Lucy","doi":"10.3168/jdsc.2024-0679","DOIUrl":"10.3168/jdsc.2024-0679","url":null,"abstract":"<div><div>Metritis typically has a greater incidence in primiparous compared with multiparous cows. In separate studies with similar design, we noted that primiparous and multiparous cows responded differently to a model developed to induce metritis via the intrauterine infusion of a bacterial challenge of <em>Fusobacterium necrophorum</em>, <em>Trueperella pyogenes</em>, and <em>Escherichia coli</em>. To understand the difference between primiparous and multiparous cows, we reanalyzed the relative abundance of bacteria genera within the vaginal microbiome during the first 2 wk postpartum from the 2 previous studies for primiparous and multiparous cows. We conducted a first reanalysis of primiparous and multiparous cows that received an identical challenge dose (10⁶ cfu of each pathogen) and a second reanalysis that compared all primiparous and multiparous cows that were or were not diagnosed with metritis regardless of challenge dose (0, 10³, 10⁶, or 10⁹ cfu per pathogen). The challenge model resulted in clinical metritis in both primiparous and multiparous cows, although some control cows (0 dose) developed metritis and, conversely, some bacterial challenge cows failed to develop metritis. Importantly, cows that contracted metritis had increased and sustained relative abundance of key metritis pathogens including <em>Fusobacterium</em>, <em>Porphyromonas</em>, <em>Helcococcus</em>, and <em>Trueperella</em> after calving regardless of parity. We unexpectedly found, however, that primiparous cows that did not develop metritis had a different bacterial profile (based on 16S ribosomal gene sequencing as well as bacterial culture) compared with multiparous cows that did not develop metritis. In primiparous nonmetritis cows, the relative abundance of the genera <em>Fusobacterium</em>, <em>Porphyromonas</em>, <em>Helcococcus</em>, and <em>Trueperella</em> was almost identical to primiparous metritis cows during the first week postpartum, but the relative abundances in nonmetritis cows decreased rapidly thereafter. The relative abundance of the same genera in nonmetritis multiparous cows did not increase or increased to a lesser extent postpartum. The different patterns of infection for nonmetritis primiparous (initial increase in relative abundance [wk 1] followed by a decrease [wk 2]) compared with nonmetritis multiparous cows (stable and low-level relative abundance for 2 wk postpartum) was found when the analysis included only challenge cows (10⁶ cfu dose) or all cows regardless of dose. We found different patterns of infection for primiparous compared with multiparous cows. This observation may explain lesser incidence of metritis in multiparous compared with primiparous cows.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 362-367"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A sampling method for differentiating breath and ruminal exhaled volatile organic compounds in dairy cows using methane as a marker","authors":"M.A. Barrientos-Blanco ,&nbsp;U. Arshad ,&nbsp;S. Giannoukos ,&nbsp;M.Z. Islam ,&nbsp;C. Kunz ,&nbsp;R. Peng ,&nbsp;S.E. Räisänen ,&nbsp;R. Zenobi ,&nbsp;M. Niu","doi":"10.3168/jdsc.2024-0732","DOIUrl":"10.3168/jdsc.2024-0732","url":null,"abstract":"<div><div>Frequent eructation in ruminant animals results in an exhaled blend of ruminal eructed and breath volatile organic compounds (VOC). The physiological distinction between the gas sources can limit the applicability of breath metabolomics (or breathomics) in describing the metabolic phenotype of cows. The objective of this study was to establish a benchmark sampling method for collecting breath samples in dairy cows while they were not eructating. Twelve multiparous mid-lactation Holstein cows were enrolled to collect (1) breath (BR; bloodborne VOC exchanged at the lungs) and (2) ruminal exhaled (RE; a mixture of VOC from ruminal eructation and breaths during eructations) samples. Gas samples were collected using a head chamber (GreenFeed system) with real-time CH₄ readings. By monitoring eructation events, a threshold of &lt;150 mV CH₄ was set to sample breath, and &gt;250 mV was used to collect BR and RE. Both samples were analyzed using secondary electrospray ionization-high resolution MS (SESI-MS) and GC. Implementing CH₄ as a marker resulted in 80% lower CH₄ concentrations in BR compared with RE. Analysis using SESI-MS revealed a total of 324 and 242 features consistently identified across all periods of the study in [M-H]⁻ and [M+H]⁺ MS ion mode, respectively, for BR and RE. In BR, 18 features exhibited greater concentrations, whereas 8 had a tendency to have greater concentrations compared with RE. In contrast, RE revealed 51 features with greater concentrations, and 13 with a tendency for greater concentrations compared with BR. Ruminal VFA acetate, propionate, and butyrate were 20.9%, 27.4%, and 32.7% greater in RE compared with BR, respectively. Lower CH₄ levels in BR and the greater VFA concentrations in the RE validated the ability of the method to differentiate breath from ruminal eructed VOC. Our study established a method to distinguish and separately collect BR and RE samples in dairy cows. This advance shows the potential to use breathomics as a reliable and noninvasive tool for metabolic assessments in ruminant research.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 438-443"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895651","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of dietary glycerol monolaurate supplementation on milk production and methane emissions in Holstein dairy cows","authors":"R.L. Culbertson ,&nbsp;P. Uzun ,&nbsp;N. Seneviratne ,&nbsp;A.B. Portela Fontoura ,&nbsp;A.N. Davis ,&nbsp;J.W. McFadden","doi":"10.3168/jdsc.2024-0567","DOIUrl":"10.3168/jdsc.2024-0567","url":null,"abstract":"<div><div>Glycerol monolaurate (GML) has antimicrobial and anti-inflammatory properties in nonruminants. In vitro, GML reduces methane (CH₄) production; however, the effects of dietary GML supplementation on milk production and CH₄ emissions have not been evaluated in dairy cattle. In a completely randomized design, 42 mid-lactation Holstein cows (3.10 ± 1.08 lactations; 40.0 ± 6.65 kg milk/d) were acclimated to a tiestall barn for 3 wk and assigned to 1 of 3 treatments (n = 14/treatment): unsupplemented (CON), low-dose GML (50 g/d; LD), or high-dose GML (150 g/d; HD) for a 21-d experimental period. Cows were fed a base diet composed of corn silage, grass haylage, and concentrates and milked thrice daily. During the final week of acclimation and the experimental period, milk was sampled consecutively for 9 milkings/week. Methane, carbon dioxide (CO₂), and hydrogen (H₂) gas measurements were collected 3 times per day over 4 d (12 samples/cow) using the GreenFeed system (C-Lock Inc., Rapid City, SD). The statistical model included fixed effects of treatment, day, and treatment × day as well as random effect of cow. Planned contrasts to compare CON versus LD and CON versus HD were employed. Dry matter intakes, milk yields, and ECM yields were not affected by treatment. However, HD cows tended to produce more 3.5% FCM, relative to CON (46.6 vs. 44.8 kg/d). Milk fat contents (4.22% vs. 4.01%) and yields (1.76 vs. 1.62 kg/d) were greater in HD, relative to CON. The LD and HD cows had higher contents and yields of de novo fatty acids, including lauric acid, relative to CON. Milk protein contents were lower for HD cows, relative to CON (3.42% vs. 3.49%). Milk protein yields were lower in LD and HD, relative to CON (1.46, 1.46, and 1.52 kg/d, respectively). Milk lactose contents and yields were not affected by treatment. Cows provided the HD treatment tended to have improved feed efficiency (i.e., kg of milk, 3.5% FCM, and ECM per unit of DMI), relative to CON. Methane production, intensity, and yield, and CO₂ and H₂ production were not affected. We conclude that dietary GML supplementation altered milk production; however, GML feeding at the levels used in this study did not modify enteric CH₄ production, intensity, or yield in dairy cattle.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 287-292"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Randomized controlled trial of intrauterine cephapirin treatment in cows of 100 days in milk or more affected by reproductive tract diseases","authors":"J. Dubuc ,&nbsp;J.C. Arango-Sabogal ,&nbsp;V. Fauteux ,&nbsp;J. Denis-Robichaud ,&nbsp;S. Buczinski","doi":"10.3168/jdsc.2024-0691","DOIUrl":"10.3168/jdsc.2024-0691","url":null,"abstract":"<div><div>The objective of the study was to quantify the effect of administering intrauterine cephapirin in cows ≥100 DIM affected by purulent vaginal discharge (PVD) or endometritis (ENDO) on pregnancy. A randomized controlled trial was conducted in 31 conveniently selected commercial dairy herds. In these herds, cows ≥100 DIM identified as nonpregnant during regular veterinary herd health visits were enrolled and tested for PVD (Metricheck score: fleck of pus or worse) and ENDO (cytobrush combined with a leukocyte esterase test: trace leukocytes or worse). Cows could be enrolled more than once during the study period, and the unit of interest in this study was enrollment (enrollments nested within cows nested within herds). Cows that tested positive for PVD (including cows with PVD only and those with both PVD and ENDO) or ENDO only were randomly allocated to either a treatment, which received 640 mg of intrauterine cephapirin benzathine, or a negative control that received no treatment. Cows unaffected by PVD or ENDO did not receive treatment (healthy control group). Cows from the 5 study groups were reinseminated by artificial insemination (AI) 10 d after enrollment following the same standardized timed-AI protocol (Ovsynch56). We used generalized linear mixed models (logit link) accounting for clustering at the cow and herd levels to compare study groups and compute the probability of pregnancy at AI. Season, DIM, and parity were included in the final model as confounders. Data from 1,686 enrollments (from 1,423 cows) were analyzed. A total of 498 examinations (29.6%) were classified as PVD (PVD only: n = 431; PVD and ENDO: n = 67), and 506 (29.9%) were classified as ENDO. The remaining 682 enrollments (40.5%) were classified as unaffected. Based on the final model, the probability of reproductive success was 42.9% for unaffected cows, 23.2% and 25.1% for untreated cows with PVD and ENDO, respectively, and 37.1% and 37.9% for treated cows with PVD and ENDO, respectively. These results showed that cephapirin improved the reproductive odds of cows ≥100 DIM affected by PVD or ENDO.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 378-382"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Early rumen development in calves: Biological processes and nutritional strategies—A mini-review","authors":"M.H. Ghaffari ,&nbsp;H.M. Hammon ,&nbsp;C. Koch","doi":"10.3168/jdsc.2024-0702","DOIUrl":"10.3168/jdsc.2024-0702","url":null,"abstract":"<div><div>The transformation of the reticulo-rumen (hereafter rumen) from a monogastric state to a functional rumen during early calf development is driven by complex transcriptional reprogramming and changes in metabolic pathways. This transformation involves coordinated morphogenesis, gene regulation, and microbial colonization. These processes promote muscle growth, epithelial differentiation, and efficient nutrient absorption and fermentation. Microbial succession begins at birth and is characterized by interaction with the host and the early introduction of solid feed. This succession establishes anaerobic, fibrolytic, and amylolytic bacterial species that are critical for nutrient absorption and productivity. In addition, optimizing grain processing in calf diets along with ensuring adequate forage intake is critical to promoting effective papilla development while maintaining stable fermentation and supporting a stable ruminal pH. Together, these factors are essential for implementing targeted nutrition and management strategies to improve calf health and productivity.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"6 3","pages":"Pages 427-431"},"PeriodicalIF":0.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143895806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}