209,737 research outputs found
Detection of interactions between myogenic and TGF mechanisms using nonlinear analysis
No full text Pages F160-F173: K. H. Chon, Y.-M. Chen, V. Z. Marmarelis, D. J. Marsh, and N.-H. Holstein-Rathlou. “Detection of interactions between myogenic and TGF mechanisms using nonlinear analysis.” Pages F168-F169: The original Figs. 8-11 do not give sufficient detail of the contour plots. New, higher resolution images are reproduced here with the original legends. </jats:p
Detection of interactions between myogenic and TGF mechanisms using nonlinear analysis
No full text Pages F160–F173: K. H. Chon, Y.-M. Chen, V. Z. Marmarelis, D. J. Marsh, and N.-H. Holstein-Rathlou. “Detection of interactions between myogenic and TGF mechanisms using nonlinear analysis.” Pages F168–F169: The original Figs. 8–11 do not give sufficient detail of the contour plots. New, higher resolution images are reproduced here with the original legends. </jats:p
UNDERSTANDING THE MARKET FOR HOLSTEIN STEERS
No full textA semi-structured interview process was combined with an econometric analysis to document the newly changed structure of the Holstein sector, to evaluate existing quality perceptions, and to assess the impact that recent changes in production practices have had on prices of Holstein steers. Results suggest that finished Holstein steer prices are driven by many of the same market factors as native steers, overturning some common quality misconceptions. The shift towards the calf-fed production model appears to have greatly affected the market for backgrounded Holstein steers, but had little impact on the prices for light Holstein feeder steers.Livestock Production/Industries, Marketing,
Body condition score and live-weight effects on milk production in Irish Holstein-Friesian dairy cows
No full textpeer-reviewedThe objective of the present study was to quantify the relationships among body condition score (BCS; scale 1 to 5), live weight (WT) and milk production in Irish Holstein-Friesian spring calving dairy cows. Data were from 66 commercial dairy herds during the years 1999 and 2000. The data consisted of up to 9886 lactations with records for BCS or WT at least once pre-calving, or at calving, nadir or 60 days post-calving. Change in BCS and WT was also calculated between time periods. Mixed models with cow included as a random effect were used to quantify the effect of BCS and WT, as well as change in each trait, on milk yield, milk fat concentration and milk protein concentration. Significant and sometimes curvilinear associations were observed among BCS at calving or nadir and milk production. Total 305-day milk yield was greatest in cows calving at a BCS of 4.25 units. However, cows calving at a BCS of 3.50 units produced only 68 kg less milk than cows calving at a BCS of 4.25 units while cows calving at 3.25 or 3.00 BCS units produced a further 50 and 114 kg less, respectively. Cows that lost more condition in early lactation produced more milk of greater fat and protein concentration, although the trend reversed in cows that lost large amounts of condition post-calving. Milk yield increased with WT although the marginal effect decreased as cows got heavier. Milk fat and protein concentration in early lactation also increased with WT pre-calving, calving and nadir, although WT did not significantly affect average lactation milk fat concentration.Allied Irish Bank; Artificial Insemination Managers Association; Holstein-Friesian Society of Great Britain and Ireland; Dairy
Levy Farmer Funds; EU Structural Funds (FEOGA
Genome-wide associations for milk production and somatic cell score in Holstein-Friesian cattle in Ireland
No full textpeer-reviewedBackground: Contemporary dairy breeding goals have broadened to include, along with milk production traits, a number of non-production-related traits in an effort to improve the overall functionality of the dairy cow. Increased indirect selection for resistance to mastitis, one of the most important production-related diseases in the dairy sector, via selection for reduced somatic cell count has been part of these broadened goals. A number of genome-wide association studies have identified genetic variants associated with milk production traits and mastitis resistance, however the majority of these studies have been based on animals which were predominantly kept in confinement and fed a concentrate-based diet (i.e. high-input production systems). This genome-wide association study aims to detect associations using genotypic and phenotypic data from Irish Holstein-Friesian cattle fed predominantly grazed grass in a pasture-based production system (low-input). Results: Significant associations were detected for milk yield, fat yield, protein yield, fat percentage, protein percentage and somatic cell score using separate single-locus, frequentist and multi-locus, Bayesian approaches. These associations were detected using two separate populations of Holstein-Friesian sires and cows. In total, 1,529 and 37 associations were detected in the sires using a single SNP regression and a Bayesian method, respectively. There were 103 associations in common between the sires and cows across all the traits. As well as detecting associations within known QTL regions, a number of novel associations were detected; the most notable of these was a region of chromosome 13 associated with milk yield in the population of Holstein-Friesian sires. Conclusions: A total of 276 of novel SNPs were detected in the sires using a single SNP regression approach. Although obvious candidate genes may not be initially forthcoming, this study provides a preliminary framework upon which to identify the causal mechanisms underlying the various milk production traits and somatic cell score. Consequently this will deepen our understanding of how these traits are expressed
A comparison of the feeding and grazing behaviour of primiparous Holstein-Friesian and Jersey × Holstein-Friesian dairy cows
No full textPeer-reviewed articleFood intake and feeding behaviour of Holstein-Friesian (HF) and Jersey × Holstein-
Friesian (J × HF) dairy cows (14 primiparous cows of each genotype) were measured
during a 54-day confinement period [cows offered a complete diet comprising conserved
forage and concentrates; 66:34 dry matter (DM) basis], while herbage intakes
and grazing behaviour were measured on three occasions during a 96-day grazing period. Throughout the experiment HF cows had a higher milk yield than J × HF cows (P < 0.05), while fat + protein yield was unaffected by genotype. During the confinement period HF cows had a higher food intake than the J × HF cows (P < 0.01), although DM intake/kg metabolic live weight (live weight0.75) was unaffected by genotype. With the exception of the number of ruminating bouts/day (P < 0.05), and idling time/day (P < 0.05), both of which were highest with the J × HF cows, genotype had no significant effect on any of the feeding behaviours examined during the confinement period. Herbage intake did not differ between genotypes during the grazing period, although when expressed on a kg live weight0.75 basis, intakes were highest with the J × HF cows (P < 0.05). While the smaller J × HF cows had fewer grazing bouts per day (P < 0.01), the mean duration of each grazing bout was longer (P < 0.001), resulting in a longer total grazing time (P < 0.05) and a greater number of grazing bites each day (P < 0.01). The smaller crossbred cows had to ‘work harder’ during the grazing period to achieve the same intakes as the larger HF cows.Department of Agriculture and Rural Development for Northern Ireland (DARD); Agri-Searc
Rapid redistribution and inhibition of renal sodium transporters during acute pressure natriuresis
No full text Pages F1004–F1014: Y. Zhang, A. K. Mircheff, C. B. Hensley, C. E. Magyar, D. G. Warnock, R. Chambrey, K.-P. Yip, D. J. Marsh, N.-H. Holstein-Rathlou, and A. A. McDonough. “Rapid redistribution and inhibition of renal sodium transporters during acute pressure natriuresis.” The immunoblot panels in Figures 2 and 5–7 were inadvertently printed from low-resolution copies of the original artwork; in addition, the panels in Fig. 6 were incorrectly labeled. The correct figures are reproduced on the following pages. (See PDF) </jats:p
Insemination factors affecting the conception rate in seasonal calving Holstein-Friesian cows
No full textpeer-reviewedDifferences in conception rate to first service between artificial inseminations (AI) carried out by commercial AI operators (CAI) or do-it-yourself operators (DIY), between natural service (NAT) and AI, between different AI sires, and between fresh and frozen-thawed semen, on Irish commercial dairy farms, were studied using logistic regression. The study comprised 12 933 potential first inseminations from 77 spring-calving dairy herds. The data were recorded during 1999 and 2000. Amongst the total, 4 394 cows had repeated records across the two years. Adjustment variables included: herd, year, parity, calving period, calving to service interval, herd size, proportion of North American Holstein-Friesian genes, peak milk yield, semen fresh or frozen-thawed status, AI sire and a cow history variable to account for the correlation structure that may exist between performance records of cows present in both years of the study. Interactions of interest were tested but were non-significant. No significant association was observed between the category of AI operator and the likelihood of conception rate to first service (PREG1). The variation in PREG1 observed within the category of operator (CAI and DIY) was investigated using the Levene test for homogeneity of variance. There was no difference between the level of variation observed within CAI and DIY operators. There were significant differences in the likelihood of PREG1 between different AI sires. Amongst the 40 most commonly used AI sires, 3 sires had a lower likelihood of PREG1 (P < 0.05) when compared to the reference AI sire (sire with PREG1 similar to the mean of the group). There was a tendency for a reduced likelihood of PREG1 with the use of fresh semen compared to frozen-thawed semen ( , P = 0.067). Amongst the adjustment variables in the model, those significantly associated with the likelihood of PREG1 included the herd, calving period, calving to first service interval and peak milk yield. No significant difference in the likelihood of PREG1 was observed between AI and NAT.AIB Bank; Holstein UK and Ireland; the
National AI Co-ops; Dairy Levy Fund (Ireland
Neue Wege der Kooperation: Schleswig-Holstein und Hamburg in einer gemeinsamen Wirtschaftsregion.
No full textWirtschaftsraum; Regionalpolitik; Regionale Konzentration; Kooperation; Wirtschaftsstruktur; Hamburg (Region); Schleswig-Holstein;
Rapid redistribution and inhibition of renal sodium transporters during acute pressure natriuresis
No full text Pages F1004'F1014: Y. Zhang, A. K. Mircheff, C. B. Hensley, C. E. Magyar, D. G. Warnock, R. Chambrey, K.-P. Yip, D. J. Marsh, N.-H. Holstein-Rathlou, and A. A. McDonough. “Rapid redistribution and inhibition of renal sodium transporters during acute pressure natriuresis.” The immunoblot panels in Figures 2 and 5–7 were inadvertently printed from low-resolution copies of the original artwork; in addition, the panels in Fig. 6 were incorrectly labeled. The correct figures are reproduced on the following pages. (See PDF) </jats:p
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