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1.
Sorghum ergot produces dihydroergosine (DHES) and related alkaloids, which cause hyperthermia in cattle. Proportions of infected panicles (grain heads), leaves and stems were determined in two forage sorghum crops extensively infected 2 to 4 weeks prior to sampling and the panicles were assayed for DHES. Composite samples from each crop, plus a third grain variety crop, were coarsely chopped and half of each sealed in plastic buckets for 6 weeks to simulate ensilation. The worst-infected panicles contained up to 55 mg DHES/kg, but dilution reduced average concentrations of DHES in crops to approximately 1 mg/kg, a relatively safe level for cattle. Ensilation significantly (P = 0.043) reduced mean DHES concentrations from 0.85 to 0.46 mg/kg.  相似文献   
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Non‐structural carbohydrates (NSC) are the primary energy available for growth and dry‐mass production in forage grasses. They are also associated with tolerance to environmental stresses, including drought. Soluble carbohydrates, especially fructans of temperate forage grasses, have been extensively studied; however, little is known about NSC of tropical grasses. These plants are abundant in the Cerrado, a savanna‐like vegetation with a definite seasonality in rainfall distribution. Such an environment presents an ideal condition for the occurrence of fructans. However, the present analysis of carbohydrates in aerial parts of twenty‐four tropical grass species, mainly from the Panicoideae subfamily in the Cerrado, shows a distinctively different NSC profile when compared with temperate grasses. Free glucose and starch are common NSC found in most plant organs. However, free fructose and sucrose‐based oligosaccharides were only found in very low amounts. Sucrose was detected in higher amounts only in stems. A linear series of malto‐oligosaccharides was found in leaf blades, sheaths and stems of most of the Cerrado grasses, except for those from the Andropogoneae tribe. These results indicate a diversity of regulatory pathways of NSC metabolism in tropical forage grasses from the Cerrado.  相似文献   
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CASE HISTORY A 21-year-old male sulphur-crested cockatoo (Cacatua galerita) was presented following the sudden appearance of blood associated with the passage of faeces and urates.

CLINICAL AND PATHOLOGICAL FINDINGS: There was fresh blood-staining of the feathers around the vent. The dorsal mucosal wall of the proctodeum was erythematous and roughened in appearance. An endoscopic biopsy was performed, and histological examination revealed multiple fronds of epithelium; the mucosa varied from simple to pseudostratified columnar epithelium, with diffuse hyperplasia of goblet cells. The underlying connective tissue stroma was well vascularised and was infiltrated with mixed inflammatory cells, comprising granulocytic cells and macrophages. PCR testing for both herpesvirus and papillomavirus, using consensus primers, was negative.

DIAGNOSIS: Cloacal papillomatosis.

CLINICAL RELEVANCE: This case manifested typical clinical signs and histological lesions of cloacal papillomatosis in the absence of demonstrable herpesvirus or papillomavirus. Veterinarians need to consider this disease in the differential diagnosis of blood in the droppings of parrots and cockatoos even in countries where psittacine herpesviruses are exotic diseases.  相似文献   
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AIM: To determine if cattle exposed to the southern saltmarsh mosquito (SSM), Aedes camptorhynchus, in the Thames-Coromandel district of New Zealand had been exposed to Ross River virus (RRV).

METHODS: A purposive sampling design was used to test cattle from seven farms located in close proximity to four sites infested with A. camptorhynchus in the Thames-Coromandel district. Sera from 207 cattle were tested for antibodies to RRV, using an ELISA and confi rmatory virus neutralisation test (VNT) as the gold standard.

RESULTS: All 207 cattle tested negative for antibodies to RRV using the ELISA and VNT.

CONCLUSIONS: This study found no evidence of exposure to RRV in cattle in locations in the Thames-Coromandel district of New Zealand where populations of SSM were present.  相似文献   
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CASE HISTORY: From 26 days of age, an Antipodes Island parakeet (Cyanoramphus unicolor) was noted to have a severe beak deformity and reduced bodyweight gain compared to its nest mate. The bird was euthanised at 43 days of age.

CLINICAL AND PATHOLOGICAL FINDINGS: The beak abnormality consisted of distortion of the right nares and severe shortening resulting in deviation of the upper maxilla to the right and cranially. On sectioning the head, copious mucoid material was found in the infraorbital sinus and the bony sinus architecture was disrupted. Histopathological examination of the infraorbital sinuses revealed a large focus of chronic but active inflammation, bony lysis on the right side and pockets of a mixed population of bacteria.

DIAGNOSIS: Severe beak deformity, likely secondary to bacterial sinusitis.

CLINICAL RELEVANCE: The case illustrates the need to look for underlying aetiologies to beak malformation, particularly in young parrots.  相似文献   
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Extract

An adult male Jackson's chameleon died with a history of intermittent periorbital swelling, anorexia and abnormal posture. On post mortem examination, there were multiple granulomas in the tongue, liver and soft palate. Histopathology revealed chronic granulomatous inflammation with yeast-like organisms and non-septate branching hyphae. Fungal cultures resulted in the growth of a Penicillium spp that could not be speciated further. The peri-orbital tissues contained a mix of necrotic bone and muscle. Sections of the brain showed three large adjacent focal areas of infarction. The kidneys showed acute nephritis and sclerotic glomeruli. The cytoplasm of some renal tubular epithelial cells contained highly eosinophilic granules. This ‘sexual segment granulation’ is normal in sexually active males of some lizard species.  相似文献   
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