Effect of different daily doses of gizzerosine on the serum 1,25-dihydroxycholecalciferol concentration in laying hens

Five groups of laying hens were treated with different gizzerosine doses (0, 2.5; 5.0; 7.5; 10.0 mg/kg/body weight of gizzerosine) daily over a 21-day period to determine the serum concentrations of 1.25-dihydroxycholecalciferol (1,25(OH)2D), total calcium, inorganic phosphorus and magnesium. Blood samples were taken on days 7, 14, and 21 of the experiment. The concentration of 1,25(OH)2D remained unchanged after day 7 in the gizzerosine-treated birds compared to the control group. After 14 days, it was significantly lower in the birds receiving. gizzerosine, compared with the control group. On day 21, 1,25(OH2)D concentrations were also significantly decreased in all 4 gizzerosine-treated groups compared with the control hens. The serum total calcium, inorganic phosphorus and total magnesium concentrations varied significantly, but irregularly, during the period of the study.     

Ulceration and stricture of the right dorsal colon after phenylbutazone administration in four horses

Four cases of ulceration and stricture of the right dorsal colon were encountered. Ulceration of the right dorsal colon is generally associated with nonsteroidal anti-inflammatory drug (NSAID) toxicosis but there are few reports of stricture following ulceration. All four horses had recent phenylbutazone use: three had been given doses well in excess of the recommended dose and in one the dose was marginally above those recommended but was combined with administration of other NSAIDs. All four horses presented with intermittent low-grade colic, weight loss and ventral oedema. Diarrhoea was also seen in three of them. All had hypoproteinaemia due to severe hypoalbuminaemia, and hyperfibrinogenaemia. Hypoalbuminaemia was less severe in one horse and this horse was successfully managed medically. Two cases were definitively diagnosed at exploratory celiotomy and two at necropsy. Exploratory celiotomy was performed in two horses: one was euthanased at surgery and one was managed successfully with medical treatment and remained normal 1 year after surgery. Medical management included feeding of a low-roughage pelleted ration, corn oil, psyllium mucilloid, and discontinuation of NSAID administration.     

Comparison of the effects of oral or subcutaneous carprofen or ketoprofen in rats undergoing laparotomy

Rats undergoing laparotomy received either carprofen (5 mg/kg) or ketoprofen (5 mg/kg) administered orally in flavoured gelatin, or by subcutaneous injection. A control group that received no analgesic showed a significant (3 per cent) fall in bodyweight (P = 0.009) after laparotomy. This decrease was greater than that seen in the groups receiving carprofen (P = 0.006) or ketoprofen (P = 0.012) administered subcutaneously, which continued to gain weight following surgery. All animals showed a significant fall in food consumption but this decrease was greater in the jelly alone group (47 per cent) than in the group receiving carprofen (17 per cent) (P = 0.015) administered subcutaneously. A significant fall in water consumption occurred in the control group (40 per cent) and in animals that received oral carprofen (13 per cent) or Ketoprofen (22 per cent). No significant decrease was seen in groups receiving either carprofen or ketoprofen administered subcutaneously (P > 0.1). This study shows that a relatively simple surgical procedure results in a major reduction in food and water consumption in rats. This reduction can be minimised by the administration of ketoprofen or carprofen (5 mg/kg subcutaneously), but higher dose rates are required if these drugs are to be administered by the oral route.     

Anaesthesia of a Sumatran tiger on eight occasions with ketamine, medetomidine and isoflurane

CASE: An 18-month-old male Sumatran tiger was referred for endoscopy and dilatation of an oesophageal stricture. Anaesthesia and bouginage was undertaken on eight occasions 2-3 weeks apart to dilate the oesophageal stricture. CLINICAL FINDINGS: On the first occasion, sedation was induced with a combination of medetomidine (30 microg/kg) and ketamine (2.35 mg/kg) given intramuscularly. Cardiopulmonary depression (characterised by bradycardia, ventricular arrhythmias, hypoventilation and cyanosis) was severe and in subsequent anaesthesias the medetomidine dose was decreased to about 18 microg/kg and the ketamine dose increased to about 3 microg/kg given intramuscularly. Immobilisation was adequate and the severity of the cardiopulmonary depression was reduced at the revised drug dosages. Atipamezole was effective in reversing both the cardiopulmonary and central nervous system depression. CONCLUSION: The dosage of medetomidine and ketamine recommended in the literature for immobilising tigers produced severe cardiopulmonary depression in this animal. A reduced dosage of medetomidine and higher dosage of ketamine provided adequate restraint with decreased cardiopulmonary depression.     

Abomasal secretion in sheep receiving adult Ostertagia circumcincta that are prevented from contact with the mucosa

AIMS: Both adult and larval Ostertagia circumcincta infections raise abomasal pH and serum gastrin and pepsinogen concentrations, either because of physical effects of the worms or from their chemical secretions. The study was designed to examine whether adult worms require contact with the gastric mucosa to effect changes in gastric secretion. METHODS: Abomasal pH and serum gastrin and pepsinogen concentrations were measured in four groups of sheep: Group A (n = 4): abomasal contents containing about 18,000 adult O. circumcincta were obtained from donor sheep, concentrated and infused into 5 microm mesh porous bags attached to surgically implanted abomasal cannulae. A second worm transplantation was carried out 1 week later to assess worm survival after 16 hours. Group B (n = 4): about 9000 adult worms, recovered after migration out of abomasal contents set in agar, were placed in small 5 microm mesh bags which were inserted through indwelling abomasal cannulae and left for 3 days. Group C (n = 2): about 3000 adult worms from the population recovered from agar were infused through abomasal cannulae which allowed. free movement in the abomasum. Group D (n = 3) was left uninfected. RESULTS: Worms transplanted directly into the abomasum (Group C) caused rapid and marked effects on abomasal secretion. Adult O. circumcincta died within 16 hours of transfer into the abomasum when they were restrained within porous bags. Nevertheless, in sheep receiving 18,000 worms, abomasal pH increased soon after new feed was presented on Days 1, 2 and 4 after worm transfer; serum gastrin was elevated in three sheep from 113 hours and serum pepsinogen increased in one animal. Sheep receiving 9000 worms showed similar trends but the results were equivocal. CONCLUSIONS: Adult O. circumcincta prevented from physical contact with the gastric mucosa by restraint in porous bags are able to raise abomasal pH. This study implicates parasite excretory-secretory products in mediating changes in gastric secretion caused by adult abomasal worms.     

Comparison of two surgical techniques for renal transplantation in cats

OBJECTIVE: To compare two surgical techniques for renal transplantation in cats with respect to graft warm ischemia time, total surgical time, operative and postoperative complications, and return to normal renal function based on measurement of plasma creatinine concentrations. STUDY DESIGN: Research study using normal cats. ANIMALS OR SAMPLE POPULATION: Fourteen adult, feline leukemia virus and feline immunodeficiency virus (FELV/FIV) negative, neutered male and spayed female cats. MATERIALS AND METHODS: Fourteen cats underwent heterotopic renal isograft transplantation with nephrectomy of the contralateral kidney. Renal arterial end-to-end anastomosis to the external iliac artery was performed in eight cats and renal arterial end-to-side anastomosis to the aorta was performed in six cats. Cats were monitored for 14 days after surgery. Renal function was evaluated by daily measurement of plasma creatinine concentrations. The cats' health was assessed by the daily recording of body weight, rectal temperature, postoperative complications, urine production, appetite, packed red blood cell volume, and total serum protein. Ultrasonographic assessment of the isograft was performed every third day. Animals were euthanatized or adopted 14 days after surgery and histopathologic analysis of biopsies or whole isograft tissues was performed. RESULTS: Nine of fourteen cats survived the 14-day study period. Although not statistically significant, mean total surgical time and graft warm ischemia time was shorter for the arterial end-to-side anastomosis. Mean daily plasma creatinine concentrations were not significantly different between the two groups. Five of eight cats (62%) undergoing the arterial end-to-end technique developed neuropraxia and lameness of the ipsilateral pelvic limb. Five cats died or were euthanatized because of other complications. CONCLUSIONS AND CLINICAL RELEVANCE: The arterial end-to-side technique appears to be the better method for renal transplantation in cats. Shorter graft warm ischemia and total surgical times, absence of pelvic limb complications, and an adequate return to normal renal function were associated with this technique.     

The effects of cyclophosphamide and its uroprotective agents, mesna and hyperbaric oxygen, on urinary bladder motility in guinea pigs

The aim of this research was to observe the effects of cyclophosphamide and its uroprotective agents, mesna and hyperbaric oxygen (HBO), on the motility of urinary bladder muscle in guinea pigs. In the experimental groups, mesna and cyclophosphamide were intraperitoneally injected at a dose of 21.5 mg/kg and 68.1 mg/kg, respectively. For the combination of mesna and cyclophosphamide, one dose of mesna was injected 20 min before cyclophosphamide administration and three additional injections of mesna were repeated every three hours. A total of 8 HBO exposures were performed at 2.8 ATA for 90 min twice daily for another experimental group. In the HBO and cyclophosphamide combined group 5 HBO exposures were given prophylactically before cyclophosphamide. The combination of mesna, HBO and cyclophosphamide was administered by the same procedure. The contractions obtained in response to acetylcholine (ACh, 10(-4) M) in the control group were reduced using cyclophosphamide and HBO individually, but not by mesna. However, the contractions belonging to the various combinations of these three agents were not different from those seen in the control group. On the other hand, the combinations of cyclophosphamide, mesna and HBO showed higher responses to ACh than the groups in which cyclophosphamide and HBO were used individually, while the responses elicited by the cyclophosphamide and HBO combination were greater than those seen in the group treated with HBO only.