Search PubMed⌕ Search

Biomedical subjects

W L Jenkins

Publications and source records attributed to W L Jenkins.

35 records · Page 2Linked to original sources
PubMed1984

Concurrent use of corticosteroids and antimicrobial drugs in the treatment of infectious diseases in large animals.

A selection of the potential risks and benefits to be gained from the concurrent use of anti-inflammatory corticosteroids and antimicrobial agents in the treatment of infectious disease processes in large animals is reviewed. Although this form of combination therapy appears to be rational, there is cause for serious concern. Precautions and guidelines are presented for the therapeutic management of those cases in which the use of corticosteroids in conjunction with antibacterial agents is unavoidable.

Adrenal Cortex↗
PubMed1984

Effects of dietary sodium bicarbonate and calcium chloride on physiological responses of lactating dairy cows in hot weather.

Twenty-four lactating cows were assigned randomly to three treatments to evaluate responses to large differences of dietary sodium and chloride. Treatments were corn-cottonseed meal-corn silage based complete rations with either: 1) .23% sodium chloride (control), 2) control plus 2.28% calcium chloride, or 3) control plus 1.70% sodium bicarbonate. Treatment effects were significant for urine pH (7.96, 5.41, 8.18), blood pH (7.50, 7.39, 7.49), partial pressure of oxygen (91.2, 99.4, 86.3 mm Hg), partial pressure of carbon dioxide (34.60, 30.57, 32.98 mm Hg), bicarbonate (26.20, 18.06, 24.64 meq/liter), total carbon dioxide (27.51, 19.18, 25.88 mM/liter), base excess (4.50, -4.31, 3.13 meq/liter), plasma chloride (93.4, 102.8, 95.7 meq/liter), serum potassium (3.26, 4.24, 4.14 meq/liter), and inorganic phosphorus (7.11, 5.61, 6.80 mg/100 ml). Blood glucose (45.1, 43.0, 55.5 mg/dl) and blood urea nitrogen (11.8, 8.7, 11.9 mg/dl) exhibited treatment effects. Respiration rates, 84.8, 61.8, 89.9 per min, and body temperatures, 39.7, 39.0, and 40.0 degrees C were significantly different. Lower intake of the high chloride diet and higher intake of the bicarbonate diet were probably responsible for some of the effects. Dietary electrolytes should receive attention in formulation because acid-base status of the animal is determined, in part, by ionic concentration and balance of the diet.

Animals↗
PubMed1979

Electrical stunning of Karakul lambs.

An apparatus designed to electrically stun Karakul lambs prior to slaughter was tested for efficiency using the cardiac pain reflex and electrocorticograms to assess unconsciousness. The electrical shock delivered by the apparatus was found to produce unconsciousness, as opposerd to curarisation, of sufficient duration to allow for subsequent slaughter.

Abattoirs↗
PubMed1978

Haematological and blood chemistry changes in ewes and lambs following supplementation with vitamin E and selenium.

1. For methods of vitamin E and selenium supplementation were evaluated using thirty-nine pregnant ewe-lambs fed on a ration containing 0.043 mg Se/kg and 25 mg vitamin E/kg. Treatments were control, fortified mineral mix (ESe salt) (300 mg vitamin E, 3 mg Se), ruminal Se pellets (505 mg Se), drench (300 mg vitamin E, 3 mg Se) and intramuscular injection (600 mg vitamin E, 3 mg Se). Only ewes supplemented, commencing approximately 50 d before parturition. 2. Birth weights were similar for all treatments and live-weight gains of lambs to 56 d of age were improved in all supplemented groups (P less than 0.05). There were no clinical cases of nutritional muscular dystrophy. 3. Se concentrations in whole blood were more than doubled in both lambs and ewes drenched or injected; responses to ESe salt and pellets were much smaller. 4. Plasma tocopherol levels were increased in injected dams and their lambs (P less than 0.001). 5. Haemoglobin concentration and erythrocyte counts were significantly higher (P less than 0.01) in control ewes and lambs than in treated lambs. 6. Lactate dehydrogenase (EC 1.1.1.27), creatine kinase (EC 2.7.3.2) and aspartate aminotransferase (EC 2.6.1.1) activities were increased in lambs from control, ESe salt and pellet groups (P less than 0.001). Glutathione peroxidase (EC 1.11.1.9) activity responded to Se supplementation in both ewes and their lambs (P less than 0.001) and the response was highest in the injected group, followed in order, by the drench, pellet, Ese salt and control groups. 7. These studies indicated that in terms of the haematological and blood chemistry changes investigated, the intramuscular injection was most effective, followed by the oral drench. Ruminal pellets and fortified salt were less satisfactory.

Animals↗
PubMed1976

Maldronksiekte in cattle: a neuronopathy caused by Solanum kwebense N.E. Br.

A neurological disease of cattle (maldronksiekte), occurring in a localized area of the Northern Transvaal, was experimentally reproduced by feeding Solanum kwebense plants to cattle. The disease is characterized by temporary loss of balance and transient epileptiform seizures precipitated by a variety of stimuli, such as exercise, handling (dipping, loading, etc) and fright. When not disturbed, most affected animals appear to be completely normal. The most conspicuous histopathological lesion is a neuronopathy manifested by vacuolar degeneration and eventual necrosis of neurones, particularly of the Purkinje cells in the cerebellum. An atrophy of the cerebellar cortex is seen grossly. The history, clinical signs and experimental reproduction of the disease, as well as the pathology of 4 experimental and 18 natural cases, are described.

Animals↗
PubMed1976

Myasthenia gravis in a Fox Terrier litter.

A report of a myasthenia gravis-like syndrome, which occurred in two Fox Terrier litter mates, is presented. The clinical signs which appeared within 5 weeks of birth, and the subsequent course of the disease are described. Treatment with neostigmine and atropine initially provided control. Some recognised features of the condition in dogs are briefly reviewed.

Animals↗
PubMed1975

A method for the in vitro study of drug transfer across ruminal epithelium.

A simple method for the in vitro study of drug diffusion across ruminal epithelium is described. The characteristics of the isolated membrane were defined by studies of ketone production from butyrate, histological studies, phenolsulphonthalein penetration and permeability to pentobarbital, antipyrine and tetraethylammonium. The preparation was found to be suitable for studies of less than 12 hours duration; after that time the integrity of the membrane as a barrier was lost due to degenerative changes. The method had a primary advantage in that experimental variables could be rigorously controlled.

Animals↗
PubMed1975

Transfer of drugs across the ruminal wall in goats.

The rates at which pentobarbital, salicylate, antipyrine, and quinine were transferred from the rumen of intact, conscious goats were measured. The rates at which the same drugs diffused from the blood plasma (under conditions of constant drug concentration) into the ruminal solution were also evaluated. These compounds were absorbed by simple diffusion, and the rates of transfer were a function of pH of the intraruminal solution. The diffusion of drugs from plasma into the reticulorumen allowed steady-state distributions to be established in some goats. The theoretical and observed steady-state distributions were compared. There were good correlations for pentobarbital and antipyrine, but not for salicylate and quinine. These findings confirm in vivo the general principles of drug transfer across ruminal epithelium that were derived from previous studies conducted in vitro.

Animals↗