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Response time of broiler chickens to cimaterol: meat tenderness, muscle composition fiber size, and carcass characteristics. 总被引:4,自引:0,他引:4
The response time to cimaterol (CIM), a beta-adrenergic agonist, by broiler chickens for carcass characteristics, muscle composition, muscle fiber size, catheptic enzyme activity, and tenderness was determined. Two trials were conducted in which chickens were fed a control diet (CON) containing 0 ppm of CIM or a diet containing 1 ppm of CIM. Trial 1 consisted of 55, 31-d-old broiler chickens individually fed for up to 48 h. At 0, 6, 12, 18, 24, and 48 h, five CON and five CIM-fed chickens were killed. Trial 2 consisted of 160, 33-d-old broiler chickens group-fed for up to 14 d. At 2, 4, 6, 8, 10, 12, and 14 d, 10 CON and 10 CIM-fed chickens were killed. The breast muscle (BM) and leg muscle (LM) weight, cathepsin B and L activities, DNA, RNA, and protein concentration, and BM shear force value (SFV) were measured in both trials. Thigh muscle (TM) SFV were measured in Trial 2 only. Fiber size of BM was measured (five birds per treatment) at d 2, 6, 10, and 14. In Trial 1, BM weight and SFV were lower in CIM-fed birds at 6 h (P less than .05). In Trial 2 BM SFV were higher at d 8 (P = .06) and d 10 (P less than .05) in CIM-fed chickens. The SFV of CIM-fed chickens were higher at d 4, 8, 10, 12, and 14 (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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L.E. Young D.H. Bartram M. Diamond A. Gregg R.S. Jones 《Veterinary anaesthesia and analgesia》1991,18(Z1):171-174
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- An enzymatic ‘reaction rate’ micro-method for the rapid routine estimation of D-B-hydroxybutyrate (D-B-HOB) in ruminant plasma, using an I.L. Multistat III centrifugal analyzer, is described.
- Reaction conditions were optimized to give a linear response for plasma D-B-HOB concentrations between 100 and 2500 μmoles per litre, at 30°C and pH 9.0.
- For the standardized method the within-run and between-run coefficients of variation for deproteinised ovine plasma were consistently less than 3.5%.
- There was good agreement between plasma concentrations obtained by the present method and both original U.V. end-point technique (r=0.927b=0.950) and a colorimetric end-point procedure (r=0.937. b=0.879).
- Utreated ovine and bovine plasma consistently exhibited high ‘blank’ activity and this was directly correlated with plasma lactate dehydrogenase (LDH) activity in both species (r=0.971; p<0.001 and r=0.949; p<0.001 respectively). The distribution of LDH activity in man was similar to sheep but, contrastingly, non-specific interference was extremely low in human plasma and unrelated to LDH. Horse, chicken and rat had negligible ‘blank” activity and comparatively low LDH levels. In both cattle and sheep non-specific interference was abolished by perchloric acid precipitation. In the sheep subtraction of ‘blank’ activity gave D-H-HOB concentrations for untreated plasma comparable to those in deproteinised samples. However, in the bovine, D-B-HOB levels remained significantly (t=6.44; p<0.001) higher even after ‘blank’ correlation. In contrast to man and other non-ruminants, perchloric acid precipitation is essential in ruminants to avoid false overestimation of plasma D-B-HOB levels.
- Plasma with EDTA as anticoagulant and serum gave concentrations of D-B-HOB approximately 60% lower, than samples containing heparin or oxalate/fluoride. However, heparin was associated with much higher (up to 50%) non-specific NAD rduction than oxalate/fluoride.
- High levels of acetoacetate (400–1000 μmoles per litre) reduced the recovery of D-B-HOB from ovine plasma by less than 10%. This effect was negated by the inclusion of hydrazine hydrates in the reaction mixture. Perchlorate ion concentrations above 25 μmoles per litre per test dramatically inhibited the assay in ovine plasma, and therefore precipitation conditions must be carefully controlled.
- Plasma with oxalate/fluoride as anticoagulant showed the greatest stability in storage; 24 hours at room temperature, one week at +4°C and at least one month at ?20°C.
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Equine herpesvirus abortion in Australia 1977 to 1982 总被引:1,自引:0,他引:1
M Sabine C Feilen L Herbert R F Jones S W Lomas D N Love J Wild 《Equine veterinary journal》1983,15(4):366-370
Until 1977 no case of abortion caused by equine herpesvirus 1 (EHV1) had been recorded in Australia although the virus, called equine rhinopneumonitis virus, had been known to have been present at least since 1962. Outbreaks of EHV1 abortion occurred in New South Wales in 1977 and in 1981. Sporadic cases of EHV1 abortion had been confirmed in some parts of Australia each year since 1975. It was concluded that an abortigenic subtype of EHV1 had been introduced to Australia in 1977 and that the previously endemic respiratory subtype occasionally caused abortion. Virus isolation in a variety of cell cultures and histopathological examination of tissue were shown to be satisfactory methods of diagnosis of EHV1 abortion. Lung proved to be the specimen of choice. Slight serological differences between "abortigenic" and "respiratory" subtypes of EHV1 were found in cross neutralisation tests. A serological survey of 219 Sydney horses of various ages revealed that most yearlings had already acquired neutralising antibody to both subtypes. 相似文献