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901.
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Feed intake, in vivo nutrient digestibility and nitrogen utilization were evaluated in male sheep fed different fractions (leaf, pseudostem, corm, whole plant) of enset, untreated or 2% urea‐ and 3% calcium oxide‐ (CaO or lime) treated wheat straw and Desmodium intortum hay as sole diets. All feeds, except D. intortum hay and enset leaf had low crude protein (CP) content. Non‐fiber carbohydrate contents were higher in enset fractions, especially in pseudostem and corm relative to other feeds. Enset leaf and pseudostem had high calcium, phosphorus and manganese contents. Corm, whole enset and D. intortum hay were rich sources of zinc. Daily dry matter and CP intakes were higher (p < 0.05) in sheep fed D. intortum hay (830 and 133 g, respectively) than those fed pseudostem (92 and 7.8 g, respectively). Organic matter digestibilities were highest for corm (0.780) and whole enset (0.776) and lowest for D. intortum hay (0.534) and untreated wheat straw (0.522). The CP digestibility ranged from 0.636 in D. intortum hay to 0.408 in corm. Nitrogen (N) balance was highest (p < 0.05) in D. intortum hay (10.4 g/day) and lowest in corm (?1.3 g/day). Enset leaf could be a useful protein supplement whereas the pseudostem and corm could be good sources of energy.  相似文献   
904.
905.
Pathogenesis of Mycobacterium bovis infection in American bison   总被引:3,自引:0,他引:3  
Eighteen 12-month-old bison were randomly placed in each of 3 groups (6 animals/group): group-1 bison were exposed to live Mycobacterium bovis, group-2 bison were inoculated with killed M bovis in oil, and group-3 bison were noninfected controls. Six, 6-month-old, tuberculin test-negative calves were placed (pen contact) with group-1 bison 30 days after exposure to M bovis. Tuberculin skin test responses (caudal fold and/or comparative cervical) were detected in all bison in groups 1 and 2 at 2, 4, 6, 10, and 12 months. Tuberculin skin test responses were observed in 2 of 6 calves at 9 and 11 months after pen contact with M bovis-exposed bison (group 1). Statistically significant lymphocyte blastogenic responses to M bovis purified protein derivative were detected in group-1 bison exposed to live M bovis at 2 months after exposure (P less than 0.025). Significant ELISA reactions were detected in sera of bison at 2 months after exposure to killed M bovis in oil (P less than 0.005) and in bison 2 months after exposure to live M bovis (P less than 0.01). Significant tuberculin skin responses, ELISA reactions, or lymphocyte blastogenic responses to M bovis purified protein derivative were not observed in the 6 control bison. Grossly visible tuberculous lesions were observed in lymph nodes and/or lung collected at necropsy in 4 of 6 bison at 12 months after exposure to live M bovis. Microscopic granulomas compatible with tuberculosis were detected in 5 of 6 bison; M bovis was isolated from tissues of each of the 6 bison.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
906.
907.
Abstract

With the objective of studying the effects of production systems on meat quality, 75 Norwegian White Sheep lambs were subjected to one of the following treatments: continuous grazing on a semi-natural lowland pasture until slaughtering (Control); continuous grazing followed by either stall-feeding on concentrate and grass silage or grazing ryegrass pasture for 44 or 24 days before slaughtering (Conc44, Conc24, Rye44, Rye24). Loin samples of M. longissimus dorsi including the subcutaneous fat were analysed for sensory attributes and fatty acid composition. Compared with the control group, a lower intensity of acid taste (P<0.05) and a lower content of C18:3n-6 fatty acids (P<0.001) were observed in the Conc44 group. The n-6/n-3 ratio was higher (P<0.001) in meat tested from the concentrate treatments compared to the ryegrass treatments. These findings indicate that the fattening of lambs on improved pastures or a concentrate-based diet prior to slaughter may alter meat characteristics.  相似文献   
908.
COMBSCORES determined using the ImmunoComb solid-phase immunoassay were compared with hemagglutination-inhibition (HI) titers specific for Newcastle disease virus (NDV) and infectious bronchitis virus (IBV) and with mean enzyme-linked immunosorbent assay (ELISA) titers determined using Agritech Systems, Inc., ELISA. COMBSCORES for NDV and IBV increased proportionately in a stepwise manner as HI titers increased. The ImmunoComb solid-phase immunoassay was ablt to produce endpoint titers on sera with NDV-HI titers of 0 through 320 and IBV-HI titers of 0 through 1024 without reaching the maximum S-value. The ImmunoComb showed good correlation with the HI assay and the Agritech ELISA and should prove to be a useful tool for serological profiling, either alone or in conjunction with the HI test or commercial ELISA.  相似文献   
909.
Wet- and dry-processing with and without heating treatments were used to dehull faba beans for preparation of flours from the cotyledons. Flour qualities were assessed by levels of tannin and trypsin inhibitor and other measures of proximate composition. High roasting temperature and shorter process time that improved the recovered cotyledon yields were verified significant by path analysis methodologies. In turn, the higher cotyledon recoveries correlated with higher protein levels and inversely with the measured tannin levels. Ash reductions were correlated to the wet processing options in hull removal while reductions in the insoluble dietary fiber were notably influenced by level of heating temperatures applied. Trypsin inhibitor levels ranged from 42 to 56% of the original with reductions tied to applications of wet and/or heat processing in each case improved by increased durations and temperatures of treatments.  相似文献   
910.
Summary A serological survey of cattle in Mali was carried out to determine the prevalence of antibody activity toBabesia bovis andB. bigemina. It was found that the level ofB. bovis infection as indicated by antibody activities was too low to be of immediate concern. However, the serological prevalence ofB. bigemina was high and this may indicate a potential disease problem. It was also found that when zebu and N'Dama cattle grazed together the N'Dama were twice as likely to have positive titres toBabesia as were the zebus.
Prevalencia Serologica De Babesiosis Bovina En Mali
Resumen Se llevó a cabo un análisis serológico en Malí, para detectar la prevalencia deBabesia bovis yBabesia bigemina. Se encontró, que la prevalencia serológica deB. bovis es baja para considerar la enfermedad una amenaza inmediata. Sinembargo, la prevalencia deB. bigemina fué alta, un problema potencial. Tambien se encontró, que cuando el ganado Cebu y N'Dama pastorea junto, el N'Dama presenta el doble de títulos serológicos deB. bigemina.

Frequence Serologique De La Babesiose Bovine Au Mali
Résumé Une enquête sérologique sur le bétail au Mali a été effectuée pour déterminer la fréquence de l'activité des anticorps àBabesia bovis etB. bigemina. On a trouvé que le degré d'infection àB. bovis tel qu'indiqué par les réactions anticorps était trop faible pour constituer un souci immédiat. Cependant la fréquence sérologique deB. bigemina était élevée, ce qui peut indiquer un problème pathologique potentiel. On a aussi noté que lorsque les zébus et les N'Dama broûtaient ensemble, les N'Dama avaient deux fois plus de chance d'avoir des titres positifs àBabesia que ne l'avaient les zébus.
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