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1.
Clinical, parasitological and biochemical parameters were evaluated in Corriedale and Crioula Lanada sheep after a single experimental infection with Haemonchus contortus. Ten 4-month-old worm-free lambs, of each breed, were infected with 200 L3 H. contortus per kg live weight and four uninfected animals of each breed were used as controls. Every week, the animals were weighed and blood and faecal samples were collected for measurement of packed cell volume (PCV), total serum protein (TSP) and albumin (ALB), and the number of eggs per gram of faeces (EPG), respectively. Twelve weeks after infection, the animals were slaughtered. The worm burden was determined and samples of the abomasal mucosa were processed for determination of the number of eosinophils, mast cells and globule leukocytes. No significant differences in PCV, TSP, ALB, parasite burden or the cell populations of the abomasal mucosa were observed between breeds, but Crioula lambs had a lower EPG count. The comparison of the infected groups with their respective controls revealed significant alterations in PCV, TSP and ALB in the Corriedale lambs and in PCV, TSP, ALB and the density of eosinophils and mast cells in the Crioula lambs.  相似文献   
2.
    
Hot-iron branding uses thermal injury to permanently identify cattle causing painful tissue damage. The primary objective was to examine the physiological and behavioral effects of oral meloxicam (MEL), compared to a control, administered at the time of hot-iron branding in Angus and Hereford steers and heifers. The secondary objectives were to investigate breed and sex effects on pain biomarkers. A total of 70 yearlings, consisting of 35 heifers and 35 steers (Angus, Hereford, or Angus × Hereford), were enrolled in the study. Animals were blocked by sex, randomized across weight, and assigned to receive MEL (1 mg/kg) or a placebo (CON). Biomarkers were assessed for 48 h after branding and included infrared thermography (IRT), mechanical nociceptive threshold (MNT), accelerometry and a visual analog scale (VAS), and serum cortisol and prostaglandin E2 metabolites (PGEM). Wound healing was assessed for 12 wk. Hair samples to quantify cortisol levels were taken prior to and 30 d post-branding. Responses were analyzed using repeated measures with calf nested in treatment as a random effect, and treatment, time, treatment by time interaction, breed, and sex as fixed effects. There was a treatment by time interaction for PGEM (P < 0.01) with MEL having lower values than CON at 6, 24, and 48 h (MEL: 18.34 ± 3.52, 19.61 ± 3.48, and 22.24 ± 3.48 pg/mL, respectively; CON: 32.57 ± 3.58, 37.00 ± 3.52, and 33.07 ± 3.48 pg/mL; P < 0.01). MEL showed less of a difference in maximum IRT values between the branded (2.27 ± 0.29 °C) and control site (3.15 ± 0.29 °C; P < 0.01). MEL took fewer lying bouts at 0–12 h (4.91 bouts ± 0.56) compared with CON (6.87 bouts ± 0.55; P < 0.01). Compared with Hereford calves, Angus calves exhibited greater serum but lower hair cortisol, greater PGEM, more lying bouts, and less healed wound scores at 3, 4, and 5 wk. Compared with heifers, steers exhibited lower PGEM, lower branding site and ocular IRT, higher MNT, and lower plasma meloxicam levels. Steers spent more time lying, took more lying bouts and had greater VAS pain, and more healed wound scores at 5 wk than heifers. Meloxicam administration at branding reduced branding and control site temperature differences and reduced lying bouts for the first 12 h. Breed and sex effects were observed across many biomarkers. Changes from baseline values for IRT, MNT, lying time, step count, VAS pain, and wound scoring all support that branding cattle is painful.  相似文献   
3.
    
Background: Hematology and serum biochemistry reference intervals in dogs may be affected by internal factors, such as breed and age, and external factors, such as the environment, diet, and lifestyle. In humans, it is well established that geographic origin and age may have an impact on reference intervals and, therefore, more specific reference intervals are sought for subpopulations. Objective: The objective of this study was to validate and transfer standard laboratory reference intervals for healthy Bernese Mountain dogs and to create new intervals for analytes where the established laboratory reference intervals were rejected. Methods: The procedure was performed using the human Clinical and Laboratory Standards Institute‐approved model modified for veterinary use. Thirty‐two dogs were included in the study using a direct a priori method, as recommended. Results: While 23 of the standard laboratory reference intervals were readily validated, 7 of the analytes (eosinophils, MCHC, alkaline phosphatase [ALP], γ‐glutamyltransferase, total bilirubin, amylase, and cholesterol) required new reference intervals according to the standard. These were calculated using the robust method. In particular, the new reference range for ALP was wide compared with the established laboratory reference interval. No clinical causes were found for differences in the results of these analytes. Conclusion: We found significant differences in 7 hematologic and serum biochemical analytes for which a breed‐specific variation appears to be the most plausible explanation. Breed‐specific reference intervals for Bernese Mountain dogs will help avoid misinterpretation of laboratory results in the diagnostic process.  相似文献   
4.
    
The relative importance of breed versus rearing experience on the grazing behaviour and diet selection of beef cattle when grazing unimproved grassland was examined over 4 years. Suckler‐reared calves of a traditional (T) breed (North Devon) or a commercial (C) breed (Simmental × Hereford Friesian) were cross‐fostered and then reared either extensively (E) on unimproved grassland or intensively (I) on agriculturally improved fertilized grassland. As yearlings, the four groups of calves (Traditional breed + Extensive rearing (TE); Traditional breed + Intensive rearing (TI); Commercial breed + Extensive rearing (CE) and Commercial breed + Intensive rearing (CI)) grazed unimproved grassland dominated by Molinia caerulea, for 2 months, and foraging behaviour was studied in a test phase. There was a breed effect on total (bites + chews; TJM) jaw movement rate (T, 78·2 vs. C, 76·5 min?1; F prob. = 0·041) during grazing and on the proportion of bites taken from plant communities with sward height ≥6 cm (T, 0·83 vs. C, 0·76; F prob. = 0·018). Rearing experience affected TJM rate in the first year in July (E, 80·0 vs. I, 76·8 min?1; F prob. = 0·015) and August (E, 78·5 vs. I, 75·5 min?1; F prob. = 0·046). The intensively reared animals grew less well on average during the test phase than those that had previous experience of the unimproved grassland as calves with their mothers (E, 0·16 vs. I, 0·09 kg day?1; F prob. = 0·033). Our findings indicate that the rearing experience of livestock appears to be as important as the breed when designing grazing managements for nature conservation areas.  相似文献   
5.
    
Hungerford, L.L. and Smith, R.D., 1997. Variations in seroprevalence and host factors for bovine anaplasmosis in Illinois. Veterinary Research Communications, 21 (1), 9-18.The modified card agglutination test (MCAT) was used to detect antibodies to Anaplasma marginale in 4994 samples collected from market cattle through the Brucellosis Eradication Program in Illinois. The MCAT reactor rate in the sample was 6.4%. The statewide prevalence estimate increased to between 7.1% and 10.7% when corrected for sampling distribution and test sensitivity and specificity. While the sample reactor rate measures the proportion of infected cattle moving through the market system and into new herds, consideration of the sampling proportions and test characteristics is important when estimating the overall prevalence. Cows were found to be at decreased risk relative to male cattle in lower-prevalence areas, but the risk was similar in higher-prevalence areas. In both higher- and lower-prevalence areas, the risk for seropositivity increased from 1 year of age onwards, but the rate of increase with age was greater in the higher-prevalence areas. Calves, however, had higher seroprevalence levels than 1-2-year-old animals. The risk was highest for Angus and Angus-Hereford cross cattle, while dairy cattle showed a decreased risk in the whole sample, but not when the analyses were stratified by prevalence level. There was a higher concentration of dairy cattle in areas with lower prevalence levels.  相似文献   
6.
    
Our previous study detected a single nucleotide polymorphism (SNP), g.1471620G > T , in the 5' flanking region of the endothelial differentiation sphingolipid G-protein-coupled receptor 1 ( EDG1 ) gene, which has been considered as a positional functional candidate for the gene responsible for marbling, and showed association of the g.1471620G > T SNP with marbling in Japanese Black beef cattle. In the present study, we investigated the allele frequency distribution of the g.1471620G > T SNP among the 5 cattle breeds, Japanese Black, Japanese Brown, Japanese Short Horn, Holstein, and Brown Swiss breeds. The T allele at the g.1471620G > T SNP associated with high marbling was found at high frequency in Japanese Black breed that has been subjected to a strong selection for high marbling, while the allele was absent or at very low frequencies in the other breeds that have not been strongly selected for high marbling. Based on this finding, we hypothesized that the pressure of the strong selection for high marbling in Japanese Black breed has increased the frequency of the T allele at the g.1471620G > T SNP in the EDG1 .  相似文献   
7.
Seventy-two pigs of three genetic groups (Brazilian indigenous breed Piau, Commercial line and Crossbred) of both sexes were slaughtered at four live weights (30, 60, 90 and 120 kg). Intramuscular fat (IMF) content in Longissimus dorsi muscle of each animal was extracted and correlated with candidate gene mRNA expression (ATN1, EEF1A2, FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1). Within slaughter weight of 120 kg, Piau and Crossbred pigs showed higher IMF content (p < 0.05) than commercial animals, with 2.48, 2.08 and 1.00% respectively. Barrows presented higher values of IMF (p < 0.05) than gilts (1.54 and 1.30% respectively). Gene expression of EEF1A2, FABP3, LDLR, OBSCN, PDHB, TRDN and RYR1 were correlated with IMF (p < 0.05) using the whole dataset. For Piau data only, expression of FABP3, LDLR, MGP, OBSCN, PDHB, TRDN and RYR1 showed correlation with IMF (p < 0.05). Genes that have important roles in lipid transportation inside the cell (FABP3) and tissues (LDLR) showed correlation with IMF of, respectively, 0.68 and 0.63 using the whole data set, and 0.90 and 0.91 using data from Piau animals. The highly positive correlation of the LDLR and FAPB3 expression with IMF content may confirm that these genes are important for fat deposition in the porcine L. dorsi muscle.  相似文献   
8.
The hocks of tied cows of a Swedish dairy herd of different breeds were radiographed. Osteoarthrosis of the arthrodial joints (spavin) was found in 37 % of the animals. Changes were seen before the cows were 2 years old, and they increased in severity with increasing age. Macroscopic and histologic examination revealed that there was osteoarthrosis also in many radiologically normal hocks. The study shows that the frequency of spavin in tied dairy cows is higher than clinical signs indicate. Apparently only cows with fusion of the arthrodial joints show the stiff hind leg movements considered typical of spavin. Differences in the incidence of spavin were found between the different breeds. Cows of the Swedish Friesian breed had the lowest (20%) and cows of the Jersey breed had the highest (50%) incidence of spavin. However, as regards the Jersey breed this was due to the high incidence (71%) found in cows raised on a high intensity feeding during the young stock period. Among the SJB cows raised on a normal intensity feeding the incidence of spavin was 25 %. Such a relationship between high young stock feeding intensity and the incidence of spavin was not seen within the other breeds. The cows in another herd with loose housing had a lower frequency of spavin than the tied cows. Offspring of animals with spavin had a higher incidence of spavin than the offspring of animals without spavin.  相似文献   
9.
10.
乌鳢苗种繁育及池塘高产养殖技术   总被引:1,自引:0,他引:1  
为探讨乌鳢的人工养殖技术,对乌鳢苗种繁育及池塘养殖阶段的关键环节:亲鱼培育、人工催产、鱼卵孵化、鱼种培育、成鱼养殖等进行了系统研究。并总结了一套实用的乌鳢养殖技术。实践证明,使用该技术能提高乌鳢鱼苗成活率和成鱼产量。  相似文献   
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