Microscopic postmortem changes in adrenal glands of the domestic fowl

Eighty-four male white leghorn chickens were killed by CO2 gas to determine the type, rate, and sequence of microscopic postmortem changes in the adrenal glands of dry and wet intact carcasses. They were held at 29 or 18 C with 50% relative humidity for different times postmortem. The sequence of microscopic postmortem changes was similar in all chickens except at 18 C, when karyorrhexis of cortical and medullary cells was observed. Cellular changes occurred earlier at 29 C than at 18 C and in dry chickens but not in chickens wet with detergent solution before storage, although slight quantitative and qualitative differences between wet and dry chickens were noted. Medullary cells underwent postmortem changes earlier than cortical cells. Nuclei of medullary cells decreased in size, with chromatin clumping leading to pyknosis, followed by cytoplasmic vacuolation, cellular shrinkage, and finally karyolysis and cell dissociation. Cortical cells had nuclear chromatin marginated, nuclei reduced in size initially, and some nuclear fading, followed by pyknosis and karyolysis. Karyorrhexis was not a prominent feature of cortical and medullary cells, although it occasionally occurred before pyknosis. Cytoplasm of cortical cells remained eosinophilic, granular, and vacuolated, but vacuoles became finer later. Pyknotic medullary cells with vacuolated cytoplasm were observed as early as 3 hr postmortem, regardless of the temperature. Diffuse pyknosis of medullary cells was noted at 18 hr in chickens held at 29 C and at 48 hr in chickens held at 18 C. Marked cortical pyknosis was noted only at 36 hr in wet chickens held at 29 C, when bacterial invasion started. Dry chickens held 36 hr at 29 C had diffuse cellular dissociation, karyolysis and cytoplasmic acidophilia, and marked bacterial invasion. Erythrocytes were pyknotic and had cytoplasmolysis. It was concluded that adrenal glands may still be useful for histopathological examination before 18 hr at 29 C and before 48 hr at 18 C.     

Comparison of plasma very low density lipoproteins and lipogenic enzymes as predictors of fat content and food conversion efficiency in selected lines of broiler chickens

1. Activities of lipogenic enzymes and plasma very low density lipoprotein (VLDL) concentrations were measured in lines of chickens with large differences in food conversion efficiency (FCE) and body fat.

2. Hepatic activities of malate dehydrogenase [EC 1.1.1.40 (MD)] and ATP citrate lyase [EC 4.1.3.8 (CL)] were correlated with the proportion of both abdominal and total body fat (r = 0·50) but were poorly correlated with gain:food ratio.

3. Activities of MD and CL in plasma were low and variable and were not correlated with any other characteristics.

4. Plasma VLDL concentration was significantly correlated with the proportion of abdominal and total body fat (r = 0·59), and gain: food ratio (r = 0·36).

     

Analysis of chicken embryonic development after removal of blastodermal cells for sexing

1. The present study evaluated developmental characteristics in the chick embryo throughout incubation following cell removal from the freshly laid egg. 2. Between 10 and a few hundred cells of the blastoderm were removed for sex diagnosis. Incubation of the treated embryos was then continued in an open egg shell culture system. 3. Cell recovery from different regions within the blastoderm was performed. 4. The experiments presented here demonstrate the persistence of the developmental potential of chicken embryos in an in ovo culture system after removal of different numbers of cells from the germinal disc prior to incubation. 5. No deviations in developmental characteristics were recorded when compared to untreated control cultures. 6. No detrimental effects of double cell biopsies could be observed. 7. A similar number of chicks developed to hatch regardless of the location of manipulation within the blastoderm.     

Development Of A Scoring System For The Veterinary Trauma Patient

An animal trauma triage (ATT) scoring system was devised to provide stratification of veterinary trauma patient populations based upon severity of injury. A retrospective population of 101 trauma patients and a prospective population of 88 patients were used to evaluate the predictive power of the ATT scoring system for survival seven days after initial presentation of the emergency service. In Both groups, the mean ATT score for survivors was significantly lower than the mean ATT score for non-survivors. In a logistic regression mode, the ATT score was found to be a significant predictor of the likelihood of survival seven days after initial presentation for both populartions. Each point increase in the ATT score resulted in a 2.3–2.6 times decreased likelihood of survival. The ATT scoring system is a useful objective classification scheme for predicting the likelihood to survive a traumatic incident and can serve as prototype for severity of injuroy scoring systems for the veterinary trauma patient.     

ANGIOGRAPHIC EVALUATION OF BOVINE FOOT ABNORMALITIES

Angiography of normal and diseased feet in cattle was carried out. In osteomyelitis of distal phalanx there was a narrowing of the digital artery with diminished vascular supply to the affected digit. An area of bone necrosis was found to be avascular. With overgrown hooves, narrowing of both the medial and lateral digital arteries with ill-defined laminar vessels was seen. The vascular pattern in cattle with cork screw claws was characterized by a dilated tortuous digital artery and a crowded arterial network resulting in increased vascular supply in the affected claw. Abrupt stricture of common digital artery, a crowded vascular network in the area of the middle phalanx and filling defects of terminal arches were demonstrated in animals with exostosis     

The prevalence of antibodies to serovars of Leptospira interrogans in horses

SUMMARY Serum samples from 272 horses, some III, were tested by the microscopic agglutination test for the presence of antibody to 12 serovars of Leptospira interrogans. Serums from 41.5% of horses reacted to one or more of the serovars tested; the most common reactions were to L. interrogans serovar ballum (15.1%), L. interrogans serovar autumnalis (11.8%), L. interrogans serovar icterohaemorrhagiae (9.9%), L. interrogans serovar pomona (8.1%) and L. interrogans serovar hardjo (7.7%).     

Radiographic characterization of diaphragmatic excursion in halothane anesthetized ponies: Effect of mode of ventilation and muscle paralysis

A radiographic technique was used to identify and characterize segmental diaphragmatic movement in anesthetized ponies breathing spontaneously and with controlled ventilation with and without muscle relaxant-induced paralysis. Paralyzed mechanically ventilated ponies were also studied at varying peak inspiratory pressures. Controlled ventilation induced a change in pattern of diaphragmatic displacement which was accentuated by paralysis and increased inspiratory pressure. In conclusion, these results indicate that uneven distribution of inspired gases is not corrected by mechanical ventilation. Furthermore, increased tidal volume during mechanical ventilation is largely wasted because this increased volume is distributed principally to the poorly perfused nondependent lung. Thus, while mechanical ventilation can alleviate hypoventilation, i.e., will decrease P_aCO₂, it will be of limited value in relieving arterial hypoxemia due to venous admixture in anesthetized patients.     

Use of an absorbable haemostatic gauze product to control bleeding in 20 horses

The objective of this study was to report our experience with an absorbable haemostatic gauze product in 20 horses with traumatic or surgical haemorrhage. The product is made from oxidised, regenerated cellulose (ORC) and is approved for external use and currently being studied to control internal bleeding in surgical settings in human subjects. Treated horses were from both practice and university settings. Signalment, anatomic location, underlying cause of bleeding and outcome were recorded in the medical record. The size of gauze, approximate time until bleeding stopped, and pre- and post-ORC adjunctive treatments were also recorded. The ORC was used in a variety of anatomic locations, including castration site, foot, flank incisions, distal limb, tooth extraction sites and the perineal region. The bleeding stopped or slowed dramatically within 90 s in 15 of 20 cases. There were no recorded complications in any of the cases. While this clinical report does not attempt to prove efficacy of the product in horses, it does show that this ORC product, which has been approved for use as a haemostatic agent in human subjects, is safe and of practical value, and may be a useful and viable option for the control of haemorrhage in a variety of equine clinical settings.     

Leukoencephalomalacia in a horse induced by fumonisin B1 isolated from Fusarium moniliforme

Each of two horses was dosed by stomach tube with culture material on maize of Fusarium moniliforme MRC 826. One horse developed severe hepatosis and mild oedema of the brain after 6 doses of 2.5 g of culture material/kg body mass/day in 7 days. The second horse, in a similar experiment but at a dosage rate of 1.25 g/kg/day, developed mild hepatosis and moderate oedema of the brain. In both animals the brain oedema was particularly noticeable in the medulla oblongata. The mycotoxin fumonisin B1 was extracted and purified from the culture material of F. moniliforme MRC, 826 which contained approximately 1 g/kg of this compound. A horse was injected intravenously 7 times from Day 0-Day 9 with 0.125 mg of fumonisin B1/kg body mass/day. Clinical signs of neurotoxicosis, which appeared on Day 8, included nervousness followed by apathy, a wide-based stance, trembling, ataxia, reluctance to move, paresis of the lower lip and tongue, and an inability to eat or drink. Euthanasia was performed on the horse on Day 10 while the animal was in a tetanic convulsion. The principal lesions were severe oedema of the brain and early, bilaterally symmetrical, focal necrosis in the medulla oblongata. This report provides experimental evidence that fumonisin B1, produced by F. moniliforme, causes equine leukoencephalomalacia.