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111.
Exacerbative effect of vitamin A on malabsorption syndrome in chicks   总被引:1,自引:0,他引:1  
The interaction between malabsorption syndrome (MAS) and dietary vitamins A and D was studied in broiler chicks reared in floor pens for 4 weeks. The chicks were naturally infected with MAS, whereas hatchmates fed the same diets but in a separate facility (battery brooder) did not exhibit signs of MAS and, therefore, were considered controls. MAS significantly reduced body weights, bone ash, serum calcium and phosphorus concentrations, and liver lipids and increased the incidence of skeletal abnormalities (tibial dyschondroplasia and rickets). Rather than ameliorating the effects of MAS, vitamin A caused a further reduction in body weight and bone ash. A possible nutrient interaction between vitamin A and vitamin D or vitamin E in birds with MAS may account for the exacerbative effect of vitamin A.  相似文献   
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Summary Experimental infections of West African Dwarf goats with Peste des Petits Ruminants (PPR) and Kata were indistinguishable clinically and pathologically. Goats convalescent from Kata resisted infection with rinderpest virus. Heterologous stimulation of secondary antibody response was observed.
Sumario Las infecciones experimentales de cabras enanas de Africa Occidental con la peste de los peque?os ruminantes y con Kata fueron clinicamente y patoligicamente indistinguibles. Cabras que convalecieron de Kata resistieron a la infección con el virus de la peste bovina. Se observó una estimulación heteróloga de la respuesta inmunitaria secundaria.

Résumé L’infection expérimentale de chèvres naines de l’Afrique de l’Ouest par le virus de la peste des petits ruminants (PPR) et par le virus du Kata a montré que les deux maladies ne présentaient pas de différences cliniques ni pathologiques. Des chèvres convalescentes de Kata ont résisté à l’infection par le virus de la peste bovine. Une stimulation hétérologue de la réponse d’anticorps secondaires a été observée.
  相似文献   
114.
This report describes an inexpensive, rapid technique for preparing 4-micron-thick undecalcified sections of avian growth plate and metaphysis using paraffin embedment, rotary microtomes, and disposable knives. Sections were stained by von Kossa's technique with a hematoxylin-and-eosin counterstain.  相似文献   
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Several cases of elevated mortality with neurologic signs in 14-to-16-day-old broilers were presented to the Poultry Diagnostic and Research Center from one local integrated company. Suspected of "spiking mortality" associated with hypoglycemia, blood glucose levels were <150 mg/dl overall, with several birds with blood glucose levels as low as 30 mg/dl. Tissues, submitted for histopathology, revealed rickets in 50% of the birds. Virus isolation and serology for reovirus and infectious bursal disease virus were negative. After evaluation of these cases, a brief investigation was conducted to determine the effects of feed restriction on the induction of rickets and resulting hypoglycemia. One-hundred 1-day-old broilers were randomly assigned to three treatment groups of: 1) ad libitum feed, 2) 25% restriction, and 3) 50% restriction. Restriction began on the fifth day of age and continued to 21 days of age. Samples collected during the course of the study included whole blood for blood glucose measurements and proximal tibiotarsus for histopathologic examination for rickets. We were unable to reproduce the clinical signs of spiking mortality, neurologic changes, or hypoglycemia experimentally. Histopathology of the growth plates of the proximal tibiotarsus did indicate mild changes consistent with rickets, but the changes were not significant between treatment groups.  相似文献   
119.
After oral exposure Campylobacter sputorum subsp. mucosalis became established in the mouth of piglets for up to eight weeks. C. sputorum subsp. mucosalis was not isolated from the same pigs each week, although some pigs were positive for a number of consecutive weeks. Spread also took place from orally dosed piglets to an undosed litter mate maintained with them. Other catalase negative, serologically distinct Campylobacters were also demonstrated in the oral cavity.  相似文献   
120.
The carbon pool in a British semi-natural woodland   总被引:4,自引:0,他引:4  
  相似文献   
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