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91.
Six structural proteins of bovine parainfluenza-3 virus (PI-3V) labeled with [35S]-methionine could be resolved by polyacrylamide gel electrophoresis (PAGE). Five structural proteins of this virus had been previously reported. The 6 proteins found in this study were: L, a 180,000 (180 kD) molecular weight (MW) large protein; P, 83 kD phosphoprotein; HN, 69 kD hemagglutinin-neuraminidase glycoprotein; NP, 66 kD nucleocapsid protein; F, 55 kD fusion glycoprotein; and M, 38 kD matrix protein. Selective labeling with [2-3H]-mannose revealed only HN and F glycoprotein bands. A cellular actin protein (43 kD), associated with many enveloped viruses, was also found as a seventh protein in bovine PI-3V.  相似文献   
92.
The objective was to examine the effect of lactation on uterine involution in post‐partum dairy cows. Holstein primiparous cows were used (n = 19, mean age: 3.9 ± 0.1 years). At calving, cows were randomly assigned to one of two treatment groups, lactating (n = 11) or non‐lactating (i.e. dried off at calving, n = 8). Examination of the reproductive tract was carried out by ultrasonography twice weekly until week 7 post‐partum. Blood samples were collected twice weekly for the analysis of progesterone to indicate the resumption of cyclicity and metabolites indicative of energy status. Uterine involution was assessed in terms of size of the uterine horns, uterine body diameter and uterine fluid volume as assessed by the amount of non‐echogenic material measured by ultrasound and position of the uterus. Vaginal mucous score was taken on day 28 post‐partum for the assessment of uterine inflammation. Resumption of cyclicity (serum progesterone > 1 ng/ml) had occurred in both groups on average by day 21 post‐partum. Concentrations of non‐esterified fatty acids and beta‐hydroxybutyrate were higher, whereas concentrations of glucose, insulin and IGF‐1 were lower (p < 0.05) in lactating compared to non‐lactating cows. Lactating cows had a smaller mean uterine body diameter (p < 0.05) than non‐lactating cows from days 28 to 42 post‐partum (day 28: 20.2 ± 1.3 vs 24.9 ± 1.5 mm, respectively) and had a lower mean uterine fluid volume up to day 49 (p < 0.05). By day 49, there was no difference in uterine diameter (15.2 ± 1.8 vs 15.2 ± 1.6 mm) or uterine fluid volume (0.11 ± 0.38 vs 0.18 ± 0.46) between lactating and non‐lactating cows, respectively. Vaginal mucous score revealed no evidence of uterine inflammation in either group. In conclusion, while lactation induced significant alterations in metabolic status, it did not have a major effect on the rate of uterine involution as defined in this study.  相似文献   
93.
An experiment was conducted to evaluate the effect of substituting different levels of hazelnut kernel oil meal (HKM) for soybean meal (SBM) in diets for broiler. A total of 450 one-day-old female Ross 308 broiler chicks were allocated randomly to three treatment groups of 150 birds each in a randomized design. Each treatment group consisted of five replicates each of 30 chicks. All diets (in mash form) were formulated to meet nutrient concentrations recommended for broilers. The experiment lasted for six weeks. In the experiment, an SBM control (SBM) diet was compared to two HKM diets, replacing 50 (50HKM) and 100% (HKM) of SBM protein, respectively. Body weight gain, feed intake and feed conversion ratio of broilers were adversely affected ( P  < 0.05) by the HKM diets at 42 days of age. Broilers fed 50HKM and HKM had growth performances similar ( P  > 0.05). The carcass yield and abdominal fat pads of birds fed diets with SBM were higher ( P  < 0.05) than those of chicks fed the 50HKM and HKM diets. The edible inner organ weight of chicks fed diets with HKM was the heaviest ( P  < 0.05). It is concluded that SBM cannot be replaced even up to 50% with HKM in commercial broiler diet.  相似文献   
94.
1. The effects of feeding a screw-press expelled cottonseed meal (CSM) to laying hens at dietary concentrations of up to 300 g/kg, were studied over a 10 week period. 2. The overall performance of hens fed on a 75g CSM/kg diet was not significantly different from controls but a 300g CSM/kg diet, containing 255 mg free gossypol/kg and 87 mg cyclopropenoid fatty acids (CPFA)/kg and giving daily intakes per hen of 26.2 mg free gossypol and 9.0 mg CPFA, significantly reduced food intake (P less than 0.01) and egg production (P less than 0.01). The 150g CSM/kg diet (daily intakes of 14.6 mg free gossypol and 4.8 mg CPFA per hen) did not produce adverse effects initially but egg production was slightly depressed towards the end of the experimental period. 3. Treatment of the CSM with a solution of ferrous sulphate hepta-hydrate for inclusion in a 300g CSM/kg diet (100 mg/kg supplemental dietary iron) further reduced food intake (P less than 0.05) and egg production (P less than 0.05). 4. Storage of eggs at warm temperatures for up to 1 month did not lead to discolourations of any kind in the CSM diet groups, but resulted in yolk mottling, a condition reduced by treatment of the CSM with iron. 5. Storage of eggs at cold temperatures for 3 months resulted in brown yolk discolouration and the initial stages of pink albumen discolouration in the 300g CSM/kg diet group; the brown yolk discolouration was reduced by treatment of the CSM with iron.  相似文献   
95.
96.
Twenty first century has witnessed remarkable achievements in green technology in material science through the development of biocomposites. Oil palm fiber (OPF) extracted from the empty fruit bunches is proven as a good raw material for biocomposites. The cellulose content of OPF is in the range of 43%–65% and lignin content is in the range of 13%–25%. A compilation of the morphology, chemical constituents and properties of OPF as reported by various researchers are collected and presented in this paper. The suitability of OPF in various polymeric matrices such as natural rubber, polypropylene, polyvinyl chloride, phenol formaldehyde, polyurethane, epoxy, polyester, etc. to form biocomposites as reported by various researchers in the recent past is compiled. The properties of these composites viz., physical, mechanical, water sorption, thermal, degradation, electrical properties, etc. are summerised. Oil palm fiber loading in some polymeric matrices improved the strength of the resulting composites whereas less strength was observed in some cases. The composites became more hydrophilic upon addition of OPF. However treatments on fiber surface improved the composite properties. Alkali treatment on OPF is preferred for improving the fiber–matrix adhesion compared to other treatments. The effect of various treatments on the properties of OPF and that of resulting composites reported by various researchers is compiled in this paper. The thermal stability, dielectric constant, electrical conductivity, etc. of the composites improved upon incorporation of OPF. The strength properties reduced upon weathering/degradation. Sisal fiber was reported as a good combination with OPF in hybrid composites.  相似文献   
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