Ostertagia ostertagi infection in the calf: effects of a trickle challenge on the hormonal control of digestive and metabolic function.
Metabolic effects of a trickle challenge with the equivalent of 10,000 infective Ostertagia ostertagi larvae per day were investigated in 12 calves allocated to infected, pair-fed control or ad libitum-fed control groups. Changes in hormone levels reflecting abomasal, pituitary and pancreatic function were monitored using radioimmunoassay techniques previously validated for use in cattle. A range of metabolic profile parameters and blood metabolites was also measured. Feed intake of the infected calves began to decline as blood gastrin and pepsinogen levels reached a peak. The depression in appetite recorded in this group was responsible for significant increases in plasma urea and non-esterified fatty acid levels and associated with an increase in growth hormone/insulin ratio. No significant difference in glucagon levels was recorded between groups. A decline in blood albumin values was also shown in the infected group and associated with a drop in nitrogen digestibility. A significant depression in circulating calcium levels was related to either the hypoalbuminaemia or impaired mineral absorption in the intestine. A decrease in plasma cholesterol values in the infected group was associated with changes in digestive function.
Fox
M T
MT
Department of Veterinary Pathology, Royal Veterinary College, London.
Gerrelli
D
D
Pitt
S R
SR
Jacobs
D E
DE
Gill
M
M
Simmonds
A D
AD
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000378:metabolism*; D004040:Dietary Carbohydrates / Q000378:metabolism; D004041:Dietary Fats / Q000378:metabolism; D004044:Dietary Proteins / Q000378:metabolism; D004063:Digestion; D004435:Eating; D004573:Electrolytes / Q000097:blood; D006728:Hormones / Q000097:blood; D007411:Intestinal Diseases, Parasitic / Q000378:metabolism / Q000662:veterinary*; D008055:Lipids / Q000097:blood; D008297:Male; D010029:Ostertagiasis / Q000378:metabolism / Q000662:veterinary*; D010435:Pepsinogens / Q000097:blood; D011897:Random Allocation; D014252:Trichostrongyloidiasis / Q000662:veterinary*
D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D004573:Electrolytes; D006728:Hormones; D008055:Lipids; D010435:Pepsinogens