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Biomedical subjects

R W Dougherty

Publications and source records attributed to R W Dougherty.

35 records · Page 2Linked to original sources
PubMed1975

Intestinal infusion of endotoxin in adrenalectomized calves.

Four adrenalectomized calves, 3 to 4 months old, were allowed to develop adrenocorticosteroid insufficiency and then were given 50 mg of Escherichia coli endotoxin by infusion via cannula into the duodenum. Several physiologic variables were studied to detect changes indicative of endotoxemia. It is concluded that adrenocorticosteroid insufficiency in calves is not an independent factor allowing an intestinal source of endotoxin to cause the development of clinical signs and physiologic changes characteristic of endotoxemia.

Adrenal Cortex Hormones↗
PubMed1975

Preliminary study of appearance of endotoxin in circulatiory system of sheep and cattle after induced grain engorgement.

Edotoxin was detected, using the limulus amebocyte lysate (LAL) test, in the blood of 3 sheep and 1 steer which had been experimentally "overfed" (induced grain engorgement) with a mixture of corn and oats (2:1). The 1st postfeeding blood samples were collected 24 hours after overfeeding. In 2 sheep and 1 steer, the 24-hours blood samples were test positive. In 1 sheep which died, the 48-hour blood sample was the 1st test-positive sample. In all cases, pre-overfeeding blood samples were taken just before overfeeding.

Animal Feed↗
PubMed1975

Grain overload in cattle and sheep: changes in microbial populations in the cecum and rumen.

Samples from the rumen and cecum of cattle and sheep were cultured to determine changes in microbial populations resulting from overfeeding with grain. Before the animals were overfed, the predominant organisms from both sides were those that grew anaerobically on a relatively nonselective ruminal fluid medium and would not grow on selective mediums designed to culture lactobacilli, streptococci, coliforms, or Clostridium perfringens. By 24 hours after overfeeding, lactic acid bacteria had increased in numbers so that they were the most numerous organisms in both the rumen and the cecum. The concentrations of coliforms and C perfringens also increased after overfeeding and were generally higher in the cecum than in the rumen.

Animal Feed↗
PubMed1975

Changes in motility and ph in the digestive tract of experimentally overfed sheep.

Motility of the digestive tract of 4 sheep was studied with radiotelemetric equipment. After base line records were made, each sheep was overfed with 70 g of grain per kilogram of body weight. The ruminoreticulum did not become static until the ingesta pH was less than 5. The cecum had the same patterns of motility and pH as did the ruminoreticulum, but these returned to normal more quickly in surviving sheep. The motility patterns of the abomasum and the small intestine were more erratic. Results indicated that considerable quantities of grain (substrate for microbial growth) reached the cecum before ruminoreticular motility was inhibited.

Abomasum↗
PubMed1975

Physiologic studies of experimentally grain-engorged cattle and sheep.

Seven sheep weighing 34 to 41 kg, each, 3 steers and 1 heifer weighing 230 to 460 kg each, were experimentally, "overfed" (induced grain engorgement). The most significant changes occurred in ruminal ingesta pH, blood pH, packed cell volume (PCV), hemoglobin (Hb), carbon dioxide pressure (PCO2, total CO2 (volume %), blood D-lactic acid, blood HCO3, and base excess. There was no common denominator that was especially pathognomonic.

Abomasum↗