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91.
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Eleven rhesus monkeys developed multifocal erythematous and a vesicular rash. Most recovered spontaneously, but a 21-year-old female became moribund and was euthanized. Findings were of vesicular dermatitis and widespread multifocal hemorrhagic necrosis of the lungs and other viscera, with intralesional intranuclear inclusions. Simian varicella virus was identified as the cause by polymerase chain reaction analysis and serologic testing.  相似文献   
94.
Acacia etbaica Schweinf. and Dichrostachys cinerea (L.) Wight et Arn. are among the common woody browse plants that naturally grow in many arid and semi-arid rangelands in sub Saharan Africa. An experiment was conducted to compare the voluntary dry matter intake, body weight gain, nitrogen balance, carcass composition and sensory attributes of goats supplemented with different levels of A. etbaica and D. cinerea fruits. Average initial body weight of the goats was 20.4 kg (± 0.8SE) and received one of the following fruit supplementation regimes for 120 days (on body weight basis, n = 4 goats per group): (1) Control, no supplement; (2) 0.5% of A. etbaica; (3) 0.5% of D. cinerea; (4) 1.0% of A. etbaica; (5) 1.0% of D. cinerea; (6) 1.5% of A. etbaica; (7) 1.5% of D. cinerea. All groups were allowed to graze/browse during the day. Compared to A. etbaica, D. cinerea fruits contained higher amounts of crude protein (182 vs 135 g/kg DM), metabolizable energy (11 vs 8.4 MJ/kg DM), and in vitro dry matter digestibility coefficient (0.7 vs 0.6). The concentrations of acid detergent fiber (ADF), sulphuric acid solubulized lignin, and tannin (soluble and condensed) were lower (P < 0.05) in D. cinerea than in A. etbaica fruits. A. etbaica fruits, however, contained higher amounts of Na, K, Fe, and Zn concentrations than D. cinerea fruits. Dry matter intake was markedly higher in supplemented groups than in the control group without supplement. Similarly, body weight gain in the control group was negative and lower (P < 0.05) than any of the supplemented groups. During the course of the experimental period (120 days) the group placed in the 1.5% D. cinerea fruit diet gained 2.6 kg whereas the control group lost 2.0 kg. Thus, the difference between these two groups was 4.6 kg, which suggests about 22.5% increment of the goats' initial body weight. N retention was negative for the control group and varied little among the remaining treatment groups. Dressing percent increased with increased level of either type of fruit supplement, the highest (51.8%) being achieved at the 1.5% D. cinerea level. There was no difference in bone tissue across treatment groups. D. cinerea fruit intake also resulted in juicy/watery flavor and tender carcass. D. cinerea fruits appeared to have no adverse effects when included at the highest level (1.5%) and could be collected and stored as dry season supplement to smallholder goats. This study shows that poor farmers can increase goat performance substantially through supplement feeding with wild fruits. Areas in Ethiopia originally set aside for provision of ecological services and biodiversity protection can also be used for wild fruit production and feeding of small stock. The effect of increasing D. cinerea fruits above the 1.5% body weight level should be a focus of future investigation. Further work on deactivation mechanism of tannins is required for A. etbaica fruits included at levels higher than 1.0%.  相似文献   
95.
Abstract

The development of a sound communication programme for the National Grazing strategy should be based on an understanding of the characteristics of the farmer population of the area concerned. The social, socio‐demographic, socio‐economie, socio‐psychological, communication and agricultural production characteristics of the population must be identified, and then be used to formulate a communication programme. Information obtained from 153 farmers in six farming communities was used to develop an extension approach for the National Grazing Strategy.  相似文献   
96.
97.
Extract

Mange in pigs caused by Sarcoptes scabiei var. suis is reported to be common in New Zealand, but, to the writer's knowledge, no investigation has been made of the number of infested farms in any area.  相似文献   
98.
Abstract

Elucidating the dynamics of a parasitic infection requiring two hosts in a natural ecosystem can be a daunting task. Myxobolus cerebralis (Mc), the myxozoan parasite that causes whirling disease in some salmonids, was detected in the Colorado River upstream of Windy Gap Reservoir (WGR) in 1988. Subsequently, whirling disease was implicated in the decline of wild Rainbow Trout Oncorhynchus mykiss in the river when WGR was identified as a point source of Mc triactinomyxons (TAMs). Between 1997 and 2004, numerous investigations began to elucidate the etiology of Mc in WGR. During this period, Mc TAM production in WGR declined more than 90%. Explanations for the decline have included differences in stream discharge between years, changes in the thermal regime of the lake, severe drought, changes in the fish population structure in WGR, and reductions in the prevalence and severity of Mc infection in salmonids in the Colorado and Fraser rivers upstream of WGR. All of these have been discredited as explanations for the reduced TAM production. In 2005, a new study was conducted to replicate the studies completed in 1998. In this paper, the results of a new real-time polymerase chain reaction assay utilized to quantify the mitochondrial 16S rDNA specific to each of four lineages of Tubifex tubifex in pooled samples of 50 oligochaetes are presented. These results suggest that compared with 1998, the densities of aquatic oligochaetes and T. tubifex have increased, TAM production has been greatly reduced, and the decline is congruent with the dominance of lineages I, V, and VI of T. tubifex—three lineages that are refractory or highly resistant to Mc infection—in the oligochaete population. While it is possible that the resistant lineages function as biofilters that deactivate Mc myxospores, the reason for the decline in TAM production in WGR remains an enigma.

Received February 15, 2012; accepted March 17, 2013  相似文献   
99.
A 3-year-old intact male Boer goat was evaluated for paraplegia. Computed tomography (CT) indicated the presence of diskospondylitis, which had previously not been reported in this species, and significant compressive myelopathy. Chronic bacterial pneumonia, epididymitis, nephritis, and soft-tissue abscesses were believed to result in hematogenous spread of bacteria to the affected disk spaces. Staphylococcus spp. and Archanobacterium pyogenes were both identified from postmortem cultures of the vertebral column.  相似文献   
100.
REASONS FOR PERFORMING STUDY: Most current treatments for placentitis in mares are empirical with few control studies to evaluate their effectiveness. OBJECTIVE: To monitor drug concentrations in allantoic fluid of pregnant pony mares using in vivo microdialysis and establish if this method would be useful for determining allantoic concentrations of drugs in normal mares and those with placentitis. METHODS: Five late gestational pony mares had microdialysis probes inserted into the allantoic fluid using transabdominal ultrasound-guided allantocentesis. Single injections of penicillin G (22,000 u/kg), gentamicin (6.6 mg/kg bwt) and flunixin meglumine (1 mg/kg bwt) were administered i.v. and dialysate samples collected continuously for 24 h. In a separate study, drug concentrations were monitored in allantoic fluid of 2 mares with experimental placentitis induced by intracervical inoculation with Streptococcus equi ssp. zooepidemicus. Drug concentrations were measured by high performance liquid chromatography (penicillin G, flunixin meglumine) or enzyme-linked immunosorbent assay (gentamicin). RESULTS: Penicillin G and gentamicin achieved average peak concentrations of 9.8+/-2.2 and 8.5+/-3.1 microg/ml, respectively, in allantoic fluid of noninfected mares. Pharmacokinetic comparisons indicate that penicillin G persists much longer in allantoic fluid than blood, whereas gentamicin exhibited similar profiles in the 2 compartments. Flunixin meglumine was not detected in allantoic fluid. In infected mares, penicillin G achieved a similar peak concentration in allantoic fluid (11.2 microg/ml) whereas peak gentamicin concentration (3.9 microg/ml) appeared to be reduced relative to drug concentrations in noninfected mares. CONCLUSIONS: Microdialysis is a useful technique for continuous in vivo monitoring of drugs in equine allantoic fluid. Our results indicate that penicillin G and gentamicin undergo effective placental transfer in pregnant mares and in 2 mares that transplacental drug transfer may be altered selectively if active placental infection is present. POTENTIAL RELEVANCE: Further studies are needed to evaluate the feasibility of using increased dose intervals for penicillin G and an increased dose rate of gentamicin to effectively combat placental infections in mares.  相似文献   
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