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111.
Ovine-derived fibroblasts were used to validate an insulin-like growth factor I (IGF-I) membrane-receptor binding assay system. Competitive binding using fibroblasts revealed that half-maximal inhibition of 125I-IGF-I binding by IGF-I was 2.3 nM. SDS-polyacrylamide gel electrophoresis analysis of specific protein-associated 125I-IGF-I was consistent with the migration of 125I-IGF-I-labeled Type I IGF receptor alpha-subunits at Mr 133,000 daltons. Further, the efficiency of two cell solubilization methods was examined and time-dependent binding equilibrium was determined for the membrane assay system. Satellite cell-derived myotubes were subsequently isolated from primary satellite cell cultures established from the semimembranosus muscles of high and low efficiency-of-gain (EOG) Targhee rams, and IGF-I receptor dynamics were measured. A membrane competitive binding study revealed that half-maximal inhibition of 125I-IGF-I binding was achieved by 1-ng IGF-I for low, and 10-ng IGF-I for high, EOG myotube membrane preparations. Kd values were similar between the high EOG (4.78 nM) and low EOG (2.95 nM) groups; however, receptor concentrations (Bmax) appeared to differ between groups. High EOG membrane receptor Bmax was 3.88 pmole/micrograms protein (19.87 pmole/micrograms DNA), whereas low EOG membrane receptor Bmax was 1.22 pmole/micrograms protein (9.28 pmole/micrograms DNA). These preliminary findings support the hypothesis that genetic selection for EOG results in altered satellite cell responsiveness to IGF-I. 相似文献
112.
Hypothalamic neurotransmitter concentrations and meat quality in stressed pigs offered excess dietary tryptophan and tyrosine. 总被引:2,自引:0,他引:2
Pale, soft, exudative (PSE) pork occurs, for the most part, from environmental stress on the pig. Amino acid intake may be related to stress susceptibility through hormone and neurotransmitter induction. Two experiments were conducted to determine whether supplementation of 5 g of tryptophan (TRP) or 10 g of tyrosine (TYR) per kilogram of a 14% CP diet would alter the response of pigs to stress as measured by hypothalamic neurotransmitter concentrations and incidence of PSE. Twenty-four (Exp. 1) and 36 (Exp. 2) 92-kg pigs were offered one of three diets: control, TRP-, or TYR-supplemented for 5 d before slaughter. Dietary TRP or TYR supplementation in Exp. 1. doubled (P less than .05) plasma TRP and TYR concentrations, respectively, and increased (P less than .05) 5-hydroxytryptamine, dihydroxyphenyl ethylamine, dihydroxyphenyl acetic acid, and homovanillic acid concentrations in the hypothalamus. Pigs that exhibited stress at slaughter had lower (P less than .05) hypothalamic concentrations of epinephrine, norepinephrine, and 5-hydroxytryptamine. In Exp. 2, pigs were trucked 55 km to a commercial meat packing facility and slaughtered without a rest period. This handling procedure was designed to invoke a high incidence of PSE pork and thus be a strong test of treatments. Supplemental dietary amino acids seemed to alter the frequency distribution of the severity of PSE pork. These data indicate that dietary manipulation of amino acid precursors of neurotransmitters may offer a practical means of reducing stress response in swine. 相似文献
113.
114.
Abstract The abundances of Aeromonas salmonicida subsp. salmonicida in the water and in the surface microlayer was studied during the initial phase of a cohabitant infection experiment with Atlantic salmon, Salmo salar L., smolt. Aeromonas salmonicida was detected in the water samples only until the intraperitoneally infected smolt were dead and had been removed. In the lipid rich surface microlayer, A. salmonicida was detected in high concentrations from the day of the first fish mortality and throughout the rest of the experiment. The significance of the high cell surface hydrophobicity is discussed as a possible reason for enrichment of A. salmonicida at the air-water interface. 相似文献
115.
P O Ahmed M F Miller S D Shackelford L P Johnson S E Williams M A McCann J O Reagan 《Journal of animal science》1992,70(2):439-443
Thirty-two crossbred cattle (steers = 17; heifers = 15) exhibiting an ultrasound fat thickness at the 12 to 13th rib region of at least 10 mm were selected from a slaughter shift at a commercial packing plant. After splitting, alternating sides of each carcass were trimmed of 1) subcutaneous fat in excess of 6.4 mm; 2) all kidney, pelvic, and heart fat; and 3) all cod or udder fat and fat in the flank region. Both sides of each carcass were fabricated into subprimals (final trim level of 6.4 mm) according to normal industry procedures. Effect of hot-fat trimming, yield grade (3, 4, and 5), and gender on hot-fat trim, fabrication fat trim, major subprimal, and total subprimal yield of untrimmed and trimmed carcasses were determined. Higher numerical yield grade (YG) corresponded with higher (P less than .05) percentages of hot-fat trim. Hot-fat trimming increased (P less than .05) the difference in fabrication fat trim between steers and heifers and between YG 3 and YG 5. Steers and heifers differed (P less than .05) in percentage of major subprimals and total subprimals when processed conventionally, whereas hot-fat trimming eliminated this difference (P less than .05). Untrimmed YG 3 carcasses had 3.1 and 5.0% higher major subprimal yield (P less than .05) than untrimmed YG 4 and YG 5 carcasses, respectively, whereas hot-fat trimming reduced this difference to 2.5% for YG 4 and to 3.7% for YG 5.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
116.
Serum amyloid A protein concentration measured by radial immunodiffusion in Abyssinian and non-Abyssinian cats 总被引:1,自引:0,他引:1
S P DiBartola J A Reiter J B Cornacoff G J Kociba M D Benson 《American journal of veterinary research》1989,50(8):1414-1417
Serum amyloid A (SAA) protein concentration was determined by use of radial immunodiffusion (RID) in 4 groups of cats: Abyssinian cats with amyloidosis, healthy Abyssinian cats without clinical evidence of amyloidosis, hospitalized non-Abyssinian cats, and clinically normal non-Abyssinian cats. Mean SAA concentration in Abyssinian cats with amyloidosis was significantly (P = 0.05) higher than mean SAA concentration in healthy Abyssinian cats without clinical evidence of amyloidosis and in hospitalized non-Abyssinian cats. Mean SAA concentration in clinically normal non-Abyssinian cats was significantly (P = 0.05) lower than mean SAA concentration in healthy Abyssinian cats without clinical evidence of amyloidosis and in hospitalized non-Abyssinian cats. Affected and healthy Abyssinian cats, however, could not reliably be distinguished on the basis of SAA concentration, because of the wide range of SAA values in these 2 groups of cats. 相似文献
117.
Effects of epidural xylazine on EEG responses to surgical stimulation during isoflurane anaesthesia in dogs 总被引:1,自引:0,他引:1
K. A. Otto S. Piepenbrock B. Rischke C. Bötel† 《Veterinary anaesthesia and analgesia》1997,24(1):33-38
The effects of epidural administration of 250 μg/kg xylazine on EEG responses to surgical stimulation of 5 different intensities were evaluated during isoflurane anaesthesia for an experimental orthopaedic procedure in dogs. The dogs were assigned randomly to one of 2 treatment groups receiving either xylazine (n = 4) or equal volumes of sterile water (n = 4) (control group) epidurally. Intense surgical stimulation during removal of a bone graft from the dorsoiliac spine of the ileum was associated with a significantly (P = 0.0339) higher increase in EEG alpha/delta ratio after epidural administration of sterile water than after epidural injection of 250 μg/kg of xylazine. In addition, the preincision baseline values for 80% spectral edge frequency were significantly (P = 0.0339) lower in the xylazine group compared to control dogs. Our results suggest that epidural administration of 250 μg/kg of xylazine during orthopaedic procedures in dogs exerts antinociceptive effects which may be in part mediated by a supraspinal effect of xylazine. 相似文献
118.
J Jieyuan P B Spradbrow 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(5):388-390
Chickens were given various fowlpox vaccines on food pellets--a commercial vaccine (strain M), and the same strain after a single passage on chorio-allantoic membrane or in chicken embryo fibroblasts. All three oral vaccines induced antibodies at levels similar to those induced by commercial strain M administered to the wingweb. The oral vaccine derived from chorio-allantoic membrane gave protection similar to that obtained with vaccine administered by the wingweb, but this required a thousandfold more virus. 相似文献
119.
120.
Two outbreaks of the egg drop syndrome were observed in quail flocks maintained on a farm together with chickens. The decrease in egg production ranged from 10.6 per cent to 50.6 per cent, and the number of soft-shelled eggs increased with the decline in egg production. In both the outbreaks haemagglutination inhibiting antibodies to EDS-76 virus were detected. Fluorescent viral antigen specific to EDS-76 virus was also detected in the lining epithelial and glandular cells of the uterus. 相似文献