JDS communications最新文献

{"title":"Mycobacterium bovis vaccination and subsequent experimental infection outcomes are associated with changes in vitamin D status in dairy calves","authors":"Rachel L. Lee ,&nbsp;Kieran G. Meade ,&nbsp;Shelley G. Rhodes ,&nbsp;Tom Ford ,&nbsp;Ilias Kyriazakis","doi":"10.3168/jdsc.2024-0547","DOIUrl":"10.3168/jdsc.2024-0547","url":null,"abstract":"<div><div>Investigations into the role of vitamin D (vitD) in the immune response of cattle are limited. The objectives of this study were therefore to investigate the association between circulating vitD concentration, tuberculosis (TB) vaccination, and <em>Mycobacterium bovis</em> infection outcomes in 24 dairy calves (&lt;8 wk old) that were housed throughout and fed a BW-based allowance. The study design incorporated 2 phases: vaccination (experimental wk 0–52) and experimental infection phase (wk 52–65). Vaccinated calves (n = 12) received a subcutaneous injection of a live attenuated TB strain at wk 0, whereas unvaccinated ones (n = 12) were injected with saline. All animals were infected with 7,600 cfu of <em>M. bovis</em> 52 wk postvaccination, and lung and lymph node tissues were assessed for pathology following euthanasia after wk 65. Blood samples were taken throughout wk 0 to 65. Serum 25-hydroxyvitamin D [25(OH)D] concentrations were measured using a commercial ELISA. A mixed-effects linear regression model revealed significantly higher 25(OH)D concentrations in the vaccinates postinfection (wk 65) compared with the nonvaccinates. Linear regression analysis between 25(OH)D concentration and the level of <em>M. bovis</em>-driven pathology revealed a negative linear relationship (i.e., higher concentrations were associated with lower pathology scores) irrespective of vaccination status. No correlation was detected between IFN-γ cytokine production and vitD concentration. Overall, the results support an impactful role for vitD in the development of effective immunity of cattle against <em>M. bovis</em>. Gaining insight into the interaction between TB vaccination, <em>M. bovis</em> infection, and vitD could potentially guide the optimization of vaccination protocols and future TB control strategies.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 622-627"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141030113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of an additional gonadotropin-releasing hormone 2 days after the initiation of a resynchronization program 25 days after artificial insemination on fertility of lactating dairy cows","authors":"Iago Matheus Rosa Leão ,&nbsp;Anthony Carbajal ,&nbsp;César Narciso ,&nbsp;Carlos Eduardo Cardoso Consentini ,&nbsp;Roberto Sartori ,&nbsp;João Paulo Nascimento Martins","doi":"10.3168/jdsc.2023-0540","DOIUrl":"10.3168/jdsc.2023-0540","url":null,"abstract":"<div><div>We investigated the effect of an additional GnRH 2 d after initiation of resynchronization on d 25 post-AI on the proportion of cows without a corpus luteum (CL) at nonpregnancy diagnosis (NPD) and pregnancy per AI (P/AI) of cows with a CL at NPD that were reinseminated. Once per week, cows that were inseminated 25 d earlier were randomly assigned to receive either a GnRH treatment only (G25) or GnRH on this day and 2 d later (G25&amp;27). Pregnancy diagnosis and CL presence were determined d 32 post-AI using ultrasonography. Nonpregnant cows with a CL were enrolled in different strategies for resynchronization of ovulation according to parity (primiparous or multiparous) and CL size. Primiparous and multiparous cows with a CL ≥20 mm in diameter continued Resynch-25 (PGF_2α on d 32; PGF_2α on d 33; GnRH on d 34; and AI on d 35). Multiparous cows with CL &lt;20 mm restarted a modified Ovsynch at NPD (GnRH – 7 d – PGF_2α – 1 d – PGF_2α – 1 d – GnRH – 1 d – AI). Primiparous cows with CL diameter &lt;20 mm started an Ovsynch+CIDR protocol on the day of NPD (GnRH + CIDR inserted – 7 d – PGF_2α + CIDR removed – 1 d – PGF_2α – 1 d – GnRH – 1 d – AI). Cows without a CL were not enrolled in any resynchronization program for a week and were excluded from fertility analyses. In multiparous cows only, the additional d 27 GnRH treatment was associated with a decreased P/AI 32 d and 102 d post-AI for the AI before treatment. The overall proportion of nonpregnant cows without CL did not differ between treatments. Yet, the GnRH treatment 27 d after AI tended to increase the proportion of overall nonpregnant cows with CL &lt;20 mm at NPD. Treatment did not affect fertility parameters of primiparous cows with a CL ≥20 mm that continued Resynch-25 at NPD. Primiparous cows in G25&amp;27 with CL &lt;20 mm and submitted to Ovsynch+CIDR at NPD tended to have decreased P/AI 102 d after AI and calving/AI. When fertility parameters of primiparous cows with a CL independent of size at NPD were analyzed combined, no effect of treatment was observed. Treatment did not affect fertility of multiparous cows with CL &lt;20 mm enrolled in Ovsynch at NPD. Multiparous cows in the G25&amp;27 group that had a CL ≥20 mm and continued Resynch-25 at NPD tended to have a greater calving/AI due to a decreased total pregnancy loss. In summary, no treatment effect was observed on the overall fertility of primiparous cows with CL at NPD. In multiparous cows, G25&amp;27 was associated with a decreased fertility of the previous AI, but it tended to increase calving/AI for multiparous cows with CL at NPD by decreasing the total pregnancy loss for the AI after treatment.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 695-699"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140784877","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of gut microbiota with cryptosporidiosis based on fecal condition in neonatal dairy calves on a farm in Japan","authors":"Yasuhiro Morita ,&nbsp;Momoko Yachida ,&nbsp;Keita Tokimitsu,&nbsp;Megumi Itoh","doi":"10.3168/jdsc.2023-0539","DOIUrl":"10.3168/jdsc.2023-0539","url":null,"abstract":"<div><div>Cryptosporidiosis is a major cause of diarrhea and is associated with high morbidity in calves. Changes in the gut microbiota exacerbate diarrhea caused by <em>Cryptosporidium parvum</em> infection in neonatal and weaned calves. However, information on the gut microbiota of neonatal calves with <em>C. parvum</em> infection is scarce, and research into the microbiome of calves is essential for developing preventive and therapeutic interventions. This study aimed to elucidate the gut microbiota of neonatal calves with cryptosporidiosis. We collected 31 fecal samples from 31 neonatal calves on a dairy farm with or without <em>C. parvum</em> antigen [CP(+) or CP(−)] using a kit and analyzed the differences in the microbiota between diarrheal (D) and normal (N) fecal samples with <em>C. parvum</em> infection based on the fecal score. The analyses revealed the α diversity indexes of fecal microbiota in CP(+)-N samples were higher than that in CP(+)-D samples. <em>Megasphaera</em> spp. and other rumen microbes were identified, and significantly associated with CP(+)-N samples compared with CP(+)-D samples by linear discriminant analysis effect size (LEfSe). We conclude that the specific gut microbiota could characterize fecal microbiota in calves with neonatal cryptosporidiosis without clinical symptoms.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 649-653"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141045934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Birth season affects cow longevity","authors":"I.M. Toledo ,&nbsp;L. Cattaneo ,&nbsp;J.E.P. Santos ,&nbsp;G.E. Dahl","doi":"10.3168/jdsc.2024-0590","DOIUrl":"10.3168/jdsc.2024-0590","url":null,"abstract":"<div><div>Dairy cow longevity is an important economic trait for producers. In modern dairy farming, longevity of dairy cows is the result of culling decisions, which are determined by several risk factors, including diseases, and reproductive and productive performance. Previous studies have documented that seasonal changes affect health, behavior, and performance of dairy cows throughout their life cycle. Increasing cow comfort by making management adjustments to decrease exposure to high temperatures during the hot months gives farmers the opportunity to decrease culling risk factors and possibly increase cow productive life. In the present study, we obtained the records of primiparous and multiparous Holstein cows from Florida (n = 10,812) and California (n = 8,197) during a 10-yr period (2012–2022). We analyzed the relationship between birth season and longevity (i.e., cows that remained in the herd for 5 or more lactations) in Florida (n = 1,567) and in California (n = 1,669). The number of cows dead, sold, the reasons why they were sold, and their relationship with birth season were also analyzed in the Florida dataset. The hypothesis was that birth in a cool season will increase the length of herd productive life and decrease the number of cows sold or dead during all lactations. The birth seasons were cool (CL; cows born in December, January, February, or March) and hot (HS; cows born in June, July, August, or September). Results showed that in Florida, most cows that remained in the herd for more than 5 lactations (i.e., 14.5% of total cow records) were born during CL compared with cows born during HS (1,129, 72% vs. 438, 28%). The same observations were made in California, where greater longevity (i.e., 5 or more lactations, representing 20.4% of total cow records) was attributed to cows born in CL compared with HS cows (939, 56.3% vs. 730, 43.7%). In Florida, a greater number of HS were sold compared with CL cows (765, 52.6% vs. 689, 47.4%). More HS cows were sold due to breeding, foot and leg, and mastitis issues in Florida. Increased cow death during the first 4 lactations was significantly associated with HS (107, 53.8% vs. 92, 46.2%). Results of this study may help farmers create opportunities to make management adjustments related to birth season, or alter negative seasonal factors (i.e., heat stress) to possibly increase cow longevity in dairy herds.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 674-678"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of feeding milk replacer supplemented with increasing concentrations of choline on feed intake, growth, and scouring incidence for 7 weeks preweaning and 1 week postweaning","authors":"Anay D. Ravelo ,&nbsp;Ellan I. Dufour ,&nbsp;Makaila Klejeski ,&nbsp;Bruce Ziegler ,&nbsp;Angie Golombeski ,&nbsp;Isaac J. Salfer","doi":"10.3168/jdsc.2024-0557","DOIUrl":"10.3168/jdsc.2024-0557","url":null,"abstract":"<div><div>The objective of this study was to evaluate the effect of increasing choline supplementation on the intake of milk replacer (MR) and calf starter (CS), growth performance, and fecal scores of calves over 8 wk. One hundred calves from commercial herds were transported to the University of Minnesota Southern Research and Outreach Center (SROC) calf facility randomized to one of 4 treatments differing in choline supplementation within MR including: 0 (C0; n = 24), 700 (C700; n = 26), 1,400 (C1400; n = 25), and 2,100 mg/kg choline (C2100; n = 25). Milk replacer contained a basal concentration of 1,650 mg/kg MR resulting in total choline concentrations in the MR of 1,650 mg/kg for C0, 2,350 mg/kg for C700, 3,050 mg/kg for C1400, and 3,750 mg/kg for C2100. Calves were weaned at 49 d, and the trial ended at 56 d. Body weight was measured at d 0, 14, 28, 42, 49, and 56. Fecal scores were measured weekly. Feed intake was measured daily and calculated every 2 wk. All feeding, BW measurements, and fecal scoring were conducted by the research staff at the University of Minnesota SROC. Growth, feed intake, and gain to feed ratio were analyzed using a linear mixed effects model with choline concentration as a fixed effect and source herd and room as random effects. Initial BW was included as a covariate for average daily gain. Fecal scores were analyzed as a chi-squared test of significance. Feeding 700 mg/kg supplemental choline increased MR intake throughout the preweaning period and increased ADG in both the preweaning and postweaning periods compared with the other treatments. No differences were observed for fecal scores across treatments. Results suggest that calf performance can be improved with MR containing 2,350 mg/kg choline, contrasting with current NASEM (2021) requirements of 1,000 mg/kg.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 553-557"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141045966","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Confirmed bacteriological diagnosis and cure of nonsevere gram-positive clinical mastitis cases enrolled in a randomized clinical trial based on results of on-farm culture","authors":"Q.K. Kolar ,&nbsp;S.M. Godden ,&nbsp;R.J. Erskine ,&nbsp;P.L. Ruegg","doi":"10.3168/jdsc.2024-0560","DOIUrl":"10.3168/jdsc.2024-0560","url":null,"abstract":"<div><div>Our objectives were to describe the confirmed bacteriological diagnosis of mastitis pathogens cultured from cases of nonsevere clinical mastitis (CM) identified as gram-positive (GP) using on-farm culture and to compare differences in bacteriological cure (BC) based on antimicrobial (AM) therapy. Cows that developed nonsevere CM in a single quarter were enrolled in a randomized clinical trial based on microbial growth on GP selective agars. Cows were randomly assigned to receive a once-daily intramammary treatment: 3 d hetacillin (n = 69), 3 d ceftiofur (n = 69), 8 d ceftiofur (n = 70), or to a nontreated group (n = 32). Etiologies were confirmed with MALDI-TOF using frozen duplicate milk samples. The crude proportion of BC was determined using milk samples collected at 14, 21, and 28 d after enrollment for cases caused by streptococci, NAS, <em>Streptococcus</em>-like organisms (consisting of <em>Enterococcus</em> and <em>Lactococcus</em>; SLO), and <em>Staphylococcus aureus.</em> Multivariable models were used to determine the effect of AM treatment on BC cure at d 21 for a subset of cases that had complete data for all covariates (n = 88). Growth on GP agar resulted in enrollment of 240 cases with confirmed etiologies distributed as <em>Streptococcus</em> spp. (21.7%; n = 52), <em>Lactococcus</em> spp. (19.2%; n = 46), NAS (16.3%; n = 39), <em>Staph. aureus</em> (6.3%; n = 16), <em>Enterococcus</em> spp. (5.0%; n = 12), and others (10%; n = 24). Thirty-five (14.5%) duplicate milk samples collected from enrolled cows had no significant growth in the laboratory and 16 (6.7%) were contaminated. Among sampling dates, combined crude BC for cases caused by target pathogens ranged from 68% to 71%. Crude BC ranged from 58% to 73% for the small group of nontreated cases (n = 12) and 69% to 71% for the combined group of cases that received intramammary AM (n = 113). Among all groups and all follow-up dates, crude BC was least for cases caused by <em>Staph. aureus</em> (ranging from 33% to 43%), followed by cases caused by SLO (58%–67%), NAS (79%–80%), and <em>Streptococcus</em> spp. (81%–91%). The proportion of BC at 21 d (LSM ± SE) did not vary between all cases that received AM (0.77 ± 0.06) and cases in the nontreated group (0.73 ± 0.16). The odds of BC at 21 d was about 5× greater for cases that occurred in primiparous as compared with multiparous cows and decreased 1.3-fold for each 1 log unit increase in SCC before the case. While this study does not have sufficient power to detect small differences in BC among pathogen groups or treatments, our results demonstrate that CM is caused by a wide diversity of GP bacteria with varying ranges of BC. These results provide justification for inclusion of negative control groups in future studies and confirm that important characteristics such as parity and history of subclinical mastitis influence the probability of BC.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 628-633"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141042439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mammary epithelial cell exfoliation increases as milk yield declines, lactation progresses, and parity increases","authors":"H.H. Webster,&nbsp;A.J. Lengi,&nbsp;B.A. Corl","doi":"10.3168/jdsc.2023-0534","DOIUrl":"10.3168/jdsc.2023-0534","url":null,"abstract":"<div><div>Milk yield (MY) naturally declines after peak lactation. One approach to improving production is to increase lactation persistency, or the length of time a cow maintains lactation. To do so, cows must maintain functional secretory mammary epithelial cells (MEC), which synthesize milk. Some viable MEC are exfoliated from the udder into milk. The objective of this experiment was to identify the magnitude and direction of association between exfoliated MEC and MY, days in milk (DIM), and parity. Our hypothesis was that MY and the quantity of exfoliated MEC were negatively correlated. Therefore, milk from low-yielding, late-lactation, and primiparous cows would contain more MEC. Thirty-six multiparous and 12 primiparous Holstein cows were sampled once during lactation. Flow cytometry was used to identify hematopoietic cells and MEC in milk using an antibody specific for cluster of differentiation-45 (CD45) and an antibody against butyrophilin 1A1 (BTN), respectively. Nucleated cells were stained with Hoechst dye, and propidium iodide was used to identify dead cells. For statistical analysis, we analyzed the effect of parity, MY, and DIM, and DIM² on the number and concentration of both total and live exfoliated MEC. Primiparous cows exfoliated fewer MEC and had a lower concentration of MEC in milk than multiparous cows regardless of lactation stage. This could reflect continued mammary growth in first lactation. Cows shed an average of 9.80 × 10⁷ ± 6.90⁷ MEC (LSM ± SEM) with a concentration of 4,582 ± 3,574 cells/mL in one milking. Milk yield was inversely related to concentration of both total and live MEC in milk. Similarly, cows in late lactation, which is associated with MY decline, exfoliated a greater number of MEC into milk. Primiparous cows had a lower MY and shed fewer total and live MEC in this study. The relationship of MY and DIM with MEC losses in milk may also contribute to declining MEC number in the mammary gland found in postpeak lactation. Understanding MEC exfoliation regulation could help develop husbandry practices that improve secretory cell retention in the mammary gland and increase lactation persistency.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 707-712"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697898","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fast and reliable method for analysis of derivatized plasma amino acids by liquid chromatography-single quadrupole-mass spectrometry","authors":"August Hoppmann,&nbsp;Sebastian I. Arriola Apelo","doi":"10.3168/jdsc.2024-0546","DOIUrl":"10.3168/jdsc.2024-0546","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The pool of free, genetically encoded AA in plasma plays an essential role not only as substrate for every protein synthesized in the body but also as signaling molecules that regulate a wide range of physiological processes. Here we present a method for the analysis of 19 of the 20 encoded AA (except Cys) in dairy cow plasma. Isolated plasma or standards for the 19 AA were gravimetrically mixed with an internal standard mix consisting of &lt;sup&gt;13&lt;/sup&gt;C isotopes of each AA. Plasma proteins were precipitated on acetonitrile and supernatants transferred to glass vials. For precolumn derivatization, plasma supernatants were buffered with sodium borate (pH 9.5–10), and AA were derivatized with 9-fluorenylmethoxycarbonyl (Fmoc) chloride. Analytes were isolated by solid-phase extraction using a strong-anionic ion exchange column and dry eluates were reconstituted in mobile phase consisting of 70% water solution of ammonium formate and 30% acetonitrile. Amino acid derivatives were separated by reverse-phase liquid chromatography over 17.5 min with a C18 column in which acetonitrile increased to 80% over the first 11 min of the method, before returning to initial levels. Electrospray ionization on negative mode was used for most AA, except Arg and Pro, for which positive mode yielded superior results. Single or double (only Lys) derivatives were measured by single quadrupole-mass spectrometry. We hypothesized that precolumn Fmoc derivatization would yield optimal resolution for quantitative analysis of the 19 targeted AA and their respective &lt;sup&gt;13&lt;/sup&gt;C internal standards, with limits of quantitation beyond physiological ranges. All 19 AA were detected with minimal background noise. An 11-point standard curve was developed for each AA. Limits of quantitation were beyond concentrations observed in plasma samples of lactating dairy cows, except for Gly where upper curve points had to be removed to maintain linearity, limiting quantitation to the upper range of physiological concentration. After removing the 4 highest concentrations from the Gly standard curve, coefficients of determination were greater than 0.999 for all of the AA. Recovery of spiked AA from plasma samples ranged from 89.9% for Phe to 100.3% for Trp. Instrument repeatability averaged 0.91 and ranged from 0.33 for Val to 2.29 for Arg. Meanwhile, sample preparation method repeatability averaged 2.02 and ranged from 1.14 for Tyr to 3.34 for Arg. Although robust methods have been developed, they depend on either availability of sophisticated instruments, mostly limited to core facilities (i.e., tandem MS methods), long and expensive chromatography without specific internal standards for each AA (i.e., HPLC-ultraviolet and HPLC-fluorescence detector), or unstable derivatization (GC-MS). Here we describe a method with high throughput, stable derivatization, high precision and recovery, and potentially more affordable than most existing methods. This method could help dairy nutrition","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 745-750"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141840488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic prediction of male fertility in Brown Swiss cattle","authors":"Hendyel A. Pacheco ,&nbsp;Attilio Rossoni ,&nbsp;Alessio Cecchinato ,&nbsp;Francisco Peñagaricano","doi":"10.3168/jdsc.2023-0533","DOIUrl":"10.3168/jdsc.2023-0533","url":null,"abstract":"<div><div>Bull fertility has been recognized as an important factor affecting dairy herd fertility. The objective of this study was to assess the feasibility of predicting male fertility in Brown Swiss cattle using genomic data. The dataset consisted of 1,102 Italian Brown Swiss bulls with sire conception rate (SCR) records and genotype data for roughly 480k SNP. The analyses included the use of linear kernel-based regression models fitting all SNPs or incorporating markers with large effect. Predictive performance was evaluated in 5-fold cross-validation using the correlation between observed and predicted SCR values and mean squared error of prediction. The entire SNP set exhibited predictive correlations around 0.19. Interestingly, the inclusion of 2 markers with large effect yielded predictive correlations around 0.32. Overall, using linear kernel-based models fitting markers with large effect is a promising approach. Our findings could help Brown Swiss breeders make enhanced genome-guided management and selection decisions on male fertility.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 568-571"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140771446","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Diurnal shifts of rumen fermentation and microbial profiles revealed circadian rhythms of rumen bacteria, methanogens, and protozoa under high-grain and high-forage diets","authors":"Yangyi Hao ,&nbsp;Jianming Xia ,&nbsp;Wei Wang ,&nbsp;Yajing Wang ,&nbsp;Zhijun Cao ,&nbsp;Hongjian Yang ,&nbsp;Linshu Jiang ,&nbsp;Zhu Ma ,&nbsp;Kangkang Chu ,&nbsp;Shuang Wang ,&nbsp;Le Luo Guan ,&nbsp;Shengli Li","doi":"10.3168/jdsc.2023-0526","DOIUrl":"10.3168/jdsc.2023-0526","url":null,"abstract":"<div><div>In this study, we investigated how the composition and population of rumen microbiota shifted in response to diurnal oscillations under 2 different diets (high grain vs. high forage). Five multiparous Holstein dairy cows with similar BW, DIM, and parity were enrolled in this study. The cows were fed high-grain (HG) diet for 21 d and then shifted to high-forage (HF) diet in the next 21 d (7-d washout and 14-d experimental period). During the experimental period, DMI and rumination activity were recorded, and rumen fluid was collected 8 times postfeeding every 6 h during the last 2 d of each dietary feeding period. The rumen microbial (bacterial, archaeal, and protozoal) population and composition were assessed using quantitative PCR and amplicon sequencing, respectively. The daily dynamic of measurements was assessed using the cosinor model. The associations between microbial taxa and rumen fermentation profiles were assessed using the linear mixed model, in which the cows were termed as random intercept effects. Daily rhythmicity was observed for DMI, rumination activity, and rumen fermentation profiles under both diets. Additionally, rumination time, rumen pH, and acetate/propionate ratio had a higher mesor (the average level of diurnal fluctuations) under HF diet than in HG diet. The amplitude (the distance between the peak and mesor) of DMI, rumen pH, ammonia nitrogen, and total volatile acid concentration were higher under the HG diet than in the HF diet. Although no significant diurnal oscillation was observed for the rumen microbial population, the relative abundance of 14 bacterial genera, 1 protozoal genus, and 2 archaeal species had significant diurnal oscillations under both HF and HG diets. Among them, the bacterial genera <em>Ruminococcus</em> and <em>Colidextribacter</em> had time at peak of rhythm within 0 to 12 h after feeding, which were also negatively associated with the rumen acetate/propionate ratio. The bacterial genus <em>Rikenellaceae_RC9_gut_group</em> had time at peak of rhythm within 12 to 24 h after feeding, which was also positively associated with the ruminal acetate/propionate ratio. Our study illustrated the daily dynamic on the rumen microbiota population and composition under different diets, and also identified the feeding-responsive rumen microbiota, highlighting that a more targeted approach is needed to manipulate rumen microbiota.</div></div>","PeriodicalId":94061,"journal":{"name":"JDS communications","volume":"5 6","pages":"Pages 700-706"},"PeriodicalIF":0.0,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140768525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}