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21.
Daniel J. Burba DVM Michael A. Collier DVM Lawrence E. Default PhD Olivia Hanson-Painton PhD Harold C. Thompson Jr. Claude L. Holder 《Journal of Equine Veterinary Science》1993,13(12):696-703
The uptake and distribution of intramuscularly (IM) administered tritium-labeled polysulfated glycosaminoglycan (3H-PSGAG) in serum, synovial fluid, and articular cartilage of eight horses was quantitated, and hyaluronic acid (HA) concentration of the middle carpal joint was evaluated in a pharmacokinetic study. A full-thickness articular cartilage defect, created on the distal articular surface of the left radial carpal bone of each horse served as an osteochondral defect model. 3H-PSGAG (500 mg) was injected IM, between 14 and 35 days after creation of the defects. Scintillation analysis of serum and synovial fluid, collected from both middle carpal joints at specific predetermined times up to 96 hours post-injection, revealed mean 3H-PSGAG concentrations peaked at 2 hours post-injection. 3H-PSGAG was detected in cartilage and subchondral bone 96 hours post-injection in samples from all eight horses. There were no statistically significant differences in 3H-PSGAG concentration of synovial fluid or cartilage between cartilage defect and control (right middle carpal) joints.
HA assay of synovial fluid revealed concentrations significantly increased at 24, 48, and 96 hours post-injection in both joints. The concentration nearly doubled 48 hours post-injection. However, no statistically significant differences were found between synovial concentrations of HA in cartilage defect and control joints.
3H-PSGAG administered IM to horses, was distributed in the blood, synovial fluid, and articular cartilage. HA concentrations in synovial fluid increased after IM administration of polysulfated glycosaminoglycan. 相似文献
22.
A. I. Rey & C. J. López-Bote 《Journal of animal physiology and animal nutrition》2001,85(9-10):281-292
The objective of this study was to assess the effect of dietary copper and/or vitamin E supplementation on composition and oxidation of M. longissimus in Iberian pigs and to compare it with meat samples from pigs produced extensively and fed with acorn and grass. Grass had the highest α-tocopherol content (> 150 mg/kg DM), while acorns had the highest copper concentration (78.1 mg/kg DM). Dietary treatment did not affect copper composition in muscle and no interactions were detected between copper and α-tocopherol. The α-tocopherol content in muscle from pigs fed diets supplemented with α-tocopheryl acetate (100 mg/kg feed) was 1.5 times greater (p < 0.0001) than those from pigs receiving a basel diet. M. longisssimus dorsi from pigs fed extensively had a higher concentration of α-tocopherol than those fed in confinement with the basel level of α-tocopheryl acetate, but lower values than pigs fed supplemented levels. Total n -3 fatty acids (p < 0.02) and hematin (p < 0.0001) concentrations were significantly higher in muscle from pigs fed extensively than when fed in confinement. Muscle homogenates from Iberian pigs fed in extensive conditions showed significantly (p < 0.02) higher susceptibility to oxidation than those from pigs fed mixed diets. Dietary α-tocopheryl acetate supplementation (100 mg/kg feed) significantly (p < 0.05) reduced lipid oxidation of muscle, while dietary copper concentration did not modify susceptibility to lipid oxidation. 相似文献
23.
Application of new procedures in the sphere of the control of sexual functions requires an extension of present knowledge of postparturient endocrinium or endogenic factors comprised in postparturient physiology of sexual activity. According to recent data, oxytocin, besides its uterotonic and luteolytic activity, acts as an ovarian factor in the local intrafollicular regulation of stereidogenesis and as a modulator of uterine secretion of prostaglandines. Based on present knowledge of oxytocin effects, this study was aimed at investigation of the influence of repeated carbetocin (Depotocin inj. Spofa) administration on the dynamics of changes in thyroxine (T4), triiodothyronine (T3), 17 beta-estradiol (E2), progesterone (P4) concentrations and their mutual correlations from the 36th hour till the 51st day after parturition. Simultaneous study of a possible delayed influence of applied carbetocin on conception of ewes after oestrus evocation on day 51 after lambing was carried out. Nineteen ewes of the Slovak Merino breed, lambed in the first decade of February, were assigned to the experimental (n = 9) and to the control group (n = 10). Experimental ewes were subjected to repeated postparturient carbetocin treatment at the dose 0.07 mg per animal. The first dose was applied i. m. in 24 hours, and the second in 72 hours after parturition. On day 51 oestrus was induced in nine ewes of each group by combined treatment with chlorsuperlutin (Agelin, vaginal pessaries, Spofa) and PMSG (500 I.U./animal). On the day of PMSG application ewes were housed together with rams for the period of the next six days. Samples of blood were taken 24 hours before parturition (-1st day), up to 36 h after parturition and on days 4, 7, 14, 17, 21, 25, 34, 42 and 51 after parturition. Concentrations of T4, T3, E2 and P4 were determined by commercial kits RIA-test-T4; RIA-test-T3; RIA-test-ESTRA and RIA-test-PROG (URVJT Kosice). Animal of the control group showed variations of T4 concentrations (Tab. I, Fig. 1) at the level of original values (59.4 +/- 9.69 nmol.l-1) up to the 21st day with the exception of temporary drop on day 4 and rise on day 7, insignificant compared to the -1st day. T4 concentrations of the control group displayed an intermittent increasing trend with the statistically insignificant peak after 36 h and on day 17, compared to the -1st day. After the 21st day controls revealed a sustained moderate increase while the experimental ewes displayed a decline of its concentrations until the 51st day.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
24.
Whittington RJ Reddacliff LA Marsh I McAllister S Saunders V 《Australian veterinary journal》2000,78(1):34-37
OBJECTIVES: To determine the frequency of excretion of Mycobacterium avium subsp paratuberculosis in Merino sheep with Johne's disease and to quantify excretion in a group of Merino sheep. DESIGN: A pen and laboratory experiment. PROCEDURE: Seven sheep selected from an affected flock on the basis of acid-fast bacilli in the sheep's faeces were housed and total daily faecal output was collected, weighed and subjected to culture for M avium subsp paratuberculosis. An end-point titration method was used to enumerate viable M avium subsp paratuberculosis in a 15 day pooled sample from five sheep that had acid-fast bacilli in their faeces while housed. RESULTS: Four sheep with subclinical multibacillary Johne's disease excreted M avium subsp paratuberculosis each day for 11 days of cultural observation. A further three sheep were intermittent excreters but lacked other evidence of infection with M avium subsp paratuberculosis. The average number of viable bacteria excreted was 1.09 x 10(8) per gram of faeces while total daily excretion was 8.36 x 10(10) viable M avium subsp paratuberculosis per sheep. Examination of faecal smears stained with Ziehl Neelsen was an unreliable means of assessing daily excretion in individual animals except in those with severe lesions. CONCLUSION: Excretion of M avium subsp paratuberculosis in Merino sheep with multibacillary Johne's disease occurred daily, proving that environmental contamination can be continuous on farms with endemic ovine Johne's disease. Faecal culture is a useful method for detecting infection as it does not appear to be affected by the timing of collection of a sample from sheep with multibacillary disease however, to maximise the sensitivity of disease surveillance using faecal culture, sampling rates should be adjusted to take account of the proportions of multibacillary and paucibacillary cases. 相似文献
25.
A 5-year-old female Holstein cow was examined for ocular discharge, periorbital swelling, an area of full-thickness corneal cellular infiltrate, fibrin, hypopyon, diffuse corneal edema, and miosis. The patient was diagnosed with a corneal stromal abscess and secondary anterior uveitis. Histopathology, mycotic culture, and polymerase chain reaction positive for Aspergillus and Fusarium DNA confirmed the presence of fungal infection. Response to therapy was adequate, and follow-up with the patient 1 year after diagnosis revealed a focal area of corneal fibrosis. 相似文献
26.
C. F. Ihler V. Rootwelt A. Heyeraas N. I. Dolvik 《Veterinary research communications》1995,19(6):487-494
The caecum and the adjacent 30 cm lengths of ileum and large colon of 201 horses from two different regions of Norway (Østlandet and Trøndelag) were examined for the presence ofAnoplocephala perfoliata. In all, 20% of the horses were infested with the cestode (27% in Østlandet and 7% in Trøndelag). The mean number of worms in infected horses from the two regions was 18 and 6, respectively.Information was obtained on the age, sex, breed, type of pasture and anthelmintic treatment after the grazing season for 183 of the 20 horses. The degree of infestation withA. perfoliata was not influenced by age, breed or sex. The odds ratio (confidence limits) for using permanent pastures that had been grazed by horses for at least the 5 last years in succession was 8.8 (3.2–24.4). There was a significantly higher prevalence ofA. perfoliata infestation in Østlandet (odds ratio 3.1 (1.1–9.1). The relatively low prevalence ofA. perfoliata infestation in Norwegian horses compared to the reported prevalences in other countries and the differences in the prevalence between Østlandet and Trøndelag are discussed. Gross pathological examination identified lesions such as mucosal thickening, hyperaemia and/or erosions. These lesions were found in all of the infected horses, compared with only 5% of the non-infected horses.Examination of faecal samples from 26 of the infected horses detected cestode eggs in only three cases. It was concluded that faecal examination is an inadequate method for the diagnosis ofA. perfoliata infestation. 相似文献
27.
T. Roth I. Pfeiffer K. Weising & B. Brenig 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2006,123(6):406-409
In this study, the cross‐amplification of a commercial multiplex set of 11 cattle (Bos taurus) microsatellites was tested on a panel of 35 European bison (Bison bonasus) individuals. After polymerase chain reaction optimization, all loci cross‐amplified successfully in investigated bisons. Number of alleles and observed and expected heterozygosity per locus are in the range of 2–4, 0.086–0.629 and 0.288–0.621 respectively. The availability of a heterologous set of multiplexed microsatellite markers derived from cattle opens an avenue for collecting profound genetic data for efficient conservation management strategies of the European bison. 相似文献
28.
Rodríguez-Vivas RI Mata-Mendez Y Pérez-Gutierrez E Wagner G 《Tropical animal health and production》2004,36(2):135-143
A cross-sectional study with a two-stage design and proportional distribution was carried out to determine the effect of management factors on the seroprevalence of Anaplasma marginale in Bos indicus cattle in the Mexican tropics. Serum was obtained from 384 cattle aged 1-2 years on 92 farms. The number of samples was proportionally distributed according to the number of farms in eastern Yucatan. Antibody activity against A. marginale was assessed using the card agglutination test. A primary screening using a 2 x K contingency table of the exposed variables with the outcomes was performed. All variables for which p < 0.20 were included in a fixed-effects log regression. The seroprevalence in the cattle was 69.75% (SE +/- 0.02). Sixty-four per cent of the farms had a seroprevalence > or = 75%. The risks related to managemental factors were stocking density ( > or = 1 animal/ha, OR = 10.94), type of acaricide (pyrethroids, OR = 3.8), dipping interval ( > 60 days, OR = 0.13) and type of veterinary instruments used (needles, scalpels, ear tattoos, and dehorners, OR = 0.17). 相似文献
29.
Bricarello PA Gennari SM Oliveira-Sequeira TC Vaz CM Gonçalves de Gonçalves I Echevarria FA 《Veterinary research communications》2002,26(6):447-457
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
30.
Biodiversity in aquatic systems in relation to aquaculture 总被引:12,自引:0,他引:12
This paper first considers the perception and dimensions of biodiversity. We suggest that biodiversity can be viewed as a biospatial, hierarchically distributed structure of variability among living organisms with five levels of complexity (and including agricultural systems). Loss of biodiversity, value of biodiversity and knowledge of aquatic biodiversity are reviewed briefly. Methods for measuring biodiversity, especially at the genetic level, are discussed and considerable emphasis is laid on effective population size as a controlling factor in biodiversity. Finally, a range of impacts of aquaculture upon biodiversity are considered, including competitive and introgressive effects from farmed stocks. The development and use of reversibly sterile strains is seen as highly beneficial to both aquaculture and the maintenance of biodiversity. 相似文献