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31.
H D Blackburn J L Rocha E P Figueiredo M E Berne L S Vieira A R Cavalcante J S Rosa 《Veterinary parasitology》1991,40(1-2):99-112
Weaned wether goats (n = 144) approximately 6 months of age were placed in a 2 x 3 factorial design experiment for 5 months to test the main effects and interaction of two levels of nutrition (growth + maintenance, NUT1; twice growth + maintenance, NUT2) and three levels of Haemonchus contortus burden (0, 500 and 2000 larvae administered every 2 weeks: W0, W500 W2000, respectively) on weight, feed intake, level of infection and packed cell volume (PCV). The rationale for the experimental design was based on the lack of information concerning the interaction between nutritional status and worm burden. Results indicated significant effects of worm burden levels on PCV, faecal egg contents (eggs per gram of feces (EPG)), actual worm numbers, feed intake and efficiency of feed utilization. Nutrition x worm burden interactions were also significant for PCV and EPG. However, the differences detected for PCV and actual worm numbers did not translate into large or consistent differences in body weight. Goats on NUT2, after an initial period, showed little difference in body weight, irrespective of worm burden. Within the NUT1 level, W0 kids weighed more than W500 or W2000 kids throughout the study. Although not statistically significant, this constitutes a trend towards an interaction between nutrition and worm burden. In both nutrition levels, there were no body weight differences between W500 and W2000 until the last 14 days. Feed intake was depressed in the first 3 months of the experiment for infected animals, but was subsequently followed by a compensatory reaction. Lower establishment rates, based on actual worm counts, were observed for the higher infection level, but in both infection levels establishment rates tended to decrease with time. Nutrition was found to be more important to counteract the consequences of a parasitic infection than to counteract the establishment of that same infection. 相似文献
32.
M H Rajab H D Blackburn T C Cartwright E A Figueiredo 《Journal of animal science》1991,69(11):4397-4405
The Texas A&M Sheep Simulation Model was used to examine genetic-environmental interactions (GEI) among Brazilian Somali, Morada Nova, and Santa Ines breeds and type and level of feed supplement in northeast Brazil. Two sets of simulations were conducted to examine effects of different supplement quality (napier grass vs cunha legume) and quantity (napier grass only). The analyses indicated the benefits from supplementing lambs at weaning during the dry season and from supplementing lactating ewes at the beginning of lambing season when forage is scarce. The cunha legume was an effective supplement, but choosing between cunha legume and napier grass is an economic consideration. Increasing the amount of napier grass supplement per ewe from 200 g/d to 400 g/d resulted in a significant GEI (i.e., different levels of response such as lamb mortality rate, lamb weaning weight, and lambing rate for different breeds). The Brazilian Somali was the least responsive, whereas the Santa Ines was the most responsive to supplementation. It was concluded that the level of supplement should be higher for the Santa Ines and Morada Nova than for the Somali. The amount of supplement should be regulated so that it neither substitutes for nor lowers the utilization of the native caatinga forage. None of the breeds was simulated to be superior in all environments. Thus, considering the wide range of resources of individual farmers, any one of these breeds may be the preferred choice, depending on the individual set of production resources. 相似文献
33.
A 17-year-old Quarter Horse, Arabian crossbred mare presented with a history of having had abdominal pain for 2 d. At surgery there was 2.6 m of descending colon strangulated within the pedicle of a mesenteric lipoma. The lipoma was resected and the descending colon appeared viable so was replaced, and the mare recovered from anaesthesia. Post-operatively, the mare failed to stabilise so was taken back to surgery. There was 2 m of infarcted descending colon which was resected and anastomosed. A drain and stainless steel stay sutures were incorporated into the ventral suture line. Post-operatively the ventral wound became infected but was resolved with therapy. The diagnosis, surgical and post-operative management and outcome are discussed. 相似文献
34.
A full ophthalmic examination was performed on 40 Siberian husky dogs using direct and indirect ophthalmoscopy, gonloscopy and nasolacrimal cannulation. Eight (20%) of the dogs were found to have distichia, 10 (25%) had excessive medial caruncular hairs, 8 (20%) had absence, displacement, or narrowing of the nasolacrimal puncta, 2 (5%) had bilateral corneal crystalline opacities, and 2 (5%) had unilateral areas of lateral corneal lipidosis. Fifty percent of the dogs had some abnormality of the iridocorneal (drainage) angle. However, in only one of these was the deformity severe enough to require glaucoma prophylaxis. An association between blue iris colour and malformation of the iridocorneal angle was noted. 相似文献
35.
A diagnosis of dicoumarol toxicity in a herd of Friesian cattle was made following investigation of the deaths of three mature cows and eleven yearling heifers. Affected stock had been fed wrapped, bailed silage containing approximately 90% sweet vernal grass ( Anthoxanthum odoratum ). Sweet vernal grass contains coumarin, which can be converted to dicoumarol, a vitamin K antagonist, through the action of moulds. Most deaths were preceded by lethargy, severe anaemia and subcutaneous and internal haemorrhage. Dicoumarol toxicosis was suspected based on clinical signs, necropsy findings and prolonged prothrombin and activated partial thromboplastin times. Dicoumarol analysis of blood from affected animals and silage confirmed the diagnosis. 相似文献
36.
C. Fortes Ferreira M. Gonzaga Pereira A. da Silva dos Santos R. Rodrigues R.E. Bressan-Smith A. PioViana R. Figueiredo Daher 《Euphytica》2003,134(1):43-46
Among the main causes of poor yield in common beans are fungal, viral and bacterial diseases. Common bacterial blight, caused
by Xanthomonas axonopodis pv. phaseoli (Xap), is one of the major bacterial diseases leading to significant losses in Brazil. Chemical control is ineffective, therefore,
the use of resistant varieties becomes an interesting alternative. The objective of the present work was to evaluate disease
resistance under natural infection of the pathogen in 109 recombinant inbred lines (F7) of P. vulgaris originated from the cross HAB-52 (susceptible — snapbean) × BAC-6 (resistant — common bean) in two different environments,
as well as to calculate genetic parameters to assist in the selection of promising materials to be used in the CBB resistance
breeding program. The data of the genetic parameters were
compared to those calculated for the F3 generation originated from the same cross. The heritability results for DI (disease index) and VI (variation index) in F3 were 26.85% and 0.26, respectively, whereas in F7 they were 91.77% and 1.36, respectively. These results demonstrate a potential to be explored for this advanced population,
that in the future, along with other pathogen variability studies and tests in other environments, may provide more information
regarding a more precise evaluation of promising genotypes to be used in common bean breeding programs aiming to obtain CBB
resistant varieties.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
37.
Role of Na+/H+ exchange by interferon-gamma in enhanced expression of JE and I-A beta genes 总被引:6,自引:0,他引:6
V Prpic S F Yu F Figueiredo P W Hollenbach G Gawdi B Herman R J Uhing D O Adams 《Science (New York, N.Y.)》1989,244(4903):469-471
The rapid transductional sequences initiated by interferon-gamma (IFN-gamma) on binding to its receptor regulate functional and genomic responses in many cells but are not well defined. Induction of macrophage activation is an example of such functional and genomic changes in response to IFN-gamma. Addition of IFN-gamma to murine macrophages, at activating concentrations, produced rapid (within 60 seconds) alkalinization of the cytosol and a concomitant, rapid influx of 22Na+. Amiloride inhibited the ion fluxes and the accumulation of specific messenger RNA for two genes induced by IFN-gamma (the early gene JE and the beta chain of the class II major histocompatibility complex gene I-A). The data indicate that IFN-gamma initiates rapid exchange of Na+ and H+ by means of the Na+/H+ antiporter and that these amiloride-sensitive ion fluxes are important to some of the genomic effects of IFN-gamma. 相似文献
38.
39.
Spatial Variability of Turbulent Mixing in the Abyssal Ocean 总被引:3,自引:0,他引:3
Ocean microstructure data show that turbulent mixing in the deep Brazil Basin of the South Atlantic Ocean is weak at all depths above smooth abyssal plains and the South American Continental Rise. The diapycnal diffusivity there was estimated to be less than or approximately equal to 0.1 x 10(-4) meters squared per second. In contrast, mixing rates are large throughout the water column above the rough Mid-Atlantic Ridge, and the diffusivity deduced for the bottom-most 150 meters exceeds 5 x 10(-4) meters squared per second. Such patterns in vertical mixing imply that abyssal circulations have complex spatial structures that are linked to the underlying bathymetry. 相似文献
40.
Cláudia Carvalhinho Windmöller Rolf-Dieter Wilken Wilson De Figueiredo Jardim 《Water, air, and soil pollution》1996,89(3-4):399-416
Thermal release analysis of mercury species in contaminated soils was performed by temperature controlled continuous heating of the samples in a furnace coupled to an Atomic Absorption Spectrophotometer (AAS). It was shown that this method allows the identification of different redox states of Hg-species through their characteristic releasing temperature ranges. The method was applied to Hg-contaminated samples from an inactive chlor-alkali production plant in former East Germany (GER), and from a gold mining area in Poconé, Mato Grosso, Brazil (BRA), as well as synthetic soil samples obtained by spiking pre-heated soil matrices (GER and BRA) with the following mercury species: Hg0, Hg2Cl2, HgCl2, HgO and HgS. The samples GER, in general, frequently showed the presence of Hg2+ probably bound to humic substances, in the case of samples with higher total carbon content. Only in highly contaminated samples (>3000 ppm of mercury) was Hg0 the predominant species. The samples BRA more frequently showed the presence of mercury species in the lower oxidation states, i.e. Hg1+ in combination with Hg0. The method allows observing changes in Hg-speciation in the samples with time, mainly changes among the oxidation states Hg0, Hg1+ and Hg2+. The treated GER matrix showed a stronger tendency to oxidise Hf-species than the BRA treated matrix, in which only added Hg0 is partially oxidised to Hg2+ and Hg1+. In contrast, the BRA matrix showed a pronounced tendency to reduce spiked Hg2+ to Hg1+. This may be the reason for the presence of Hg1+ in the majority of original BRA samples. The method appears to be very useful to study speciation of mercury and its dynamics. It can be used as a tool for monitoring mercury oxidation states and/or reactions of mercury in soils. 相似文献