THE EFFECTS OF CT1341, THIOPENTONE AND INDUCTION-DELIVERY TIME ON THE BLOOD GAS AND ACID-BASE STATUS OF LAMBS DELIVERED BY CAESAREAN OPERATION AND ON THE ONSET OF RESPIRATION

Caesarean sections were performed on 18 Romney ewes on day 144 of pregnancy. Anaesthesia was induced in 9 ewes with CT 1341 and in 9 ewes with thiopentone and maintained in both groups with halothane administered with oxygen. Surgery was performed with the ewes in lateral recumbency, with respiration unassisted. Blood samples were collected from the intact umbilical artery at the time of delivery and analysed for PO2, PCO2, pH (base deficit was derived). The intervals between ewe induction and lamb delivery (lD), delivery and the onset of breathing (TSR), and delivery and the lamb standing were recorded. Lambs in the CT 1341 group both breathed and stood sooner than lambs in the thiopentone group. Significant linear relationships were only found in the CT 1341 group between TSR interval and PCO2 and pH. No significant correlations were found between the lD interval and any of the biochemical characteristics. The results of this study suggest that lateral recumbency does not interfere with uteroplacental circulation, that CT 1341 (2.2 mg/kg) is associated with less neonatal depression than thiopentone (10 mg/kg) and that severe neonatal hypercarbia may delay the onset of respiration in lambs with minimal drug depression.     

Monensis toxicity in lambs

A group of 100 purebred lambs was accidentally fed ten times the prescribed level of monensin in its grower ration. The first clinical sign was feed refusal. When the lambs were forced to eat the ration by withdrawal of other feeds, clinical signs developed within 48 hours in 15 to 20% of the group. These included recumbency, inability to rise, stiff gaits and a tendency to walk on their toes. Clinical examination, history, laboratory and necropsy results, along with feed analysis confirmed the diagnosis of monensin toxicosis.     

Variable nature of border disease on a single farm: clinical and pathological description of affected sheep

The clinical, pathological and virological findings in cases of Border disease occurring on a farm were studied. Fourteen abnormal lambs approximately three months old were obtained and were necropsied within 18 months at death or slaughter. Another lamb born during the study to a persistently infected ewe was also examined. The findings of these 15 animals are presented in three groupings. The animals of group A were persistently viraemic and hypomyelinogenesis was present in two lambs at one and 14 weeks old. Systemic, chronic, multifocal inflammation including nephritis, myocarditis and pneumonitis was found in older sheep. Group B lambs were non-viraemic and the predominant necropsy finding was cystic cerebral cavitation of variable severity. Histological examination showed cerebellar dysplasia and in two animals the retinas also showed multifocal photoreceptor cell atrophy. Lambs in group C were also non-viraemic and although these failed to thrive, no consistent pathological changes were found. It is concluded that the dams of animals in group A were infected in early pregnancy while those of animals in groups B and C were infected at mid-gestation or later.     

Electromechanical registration of the resting behavior of fattening pigs]

The resting behaviour of four weanling pigs has been continuously recorded by an electromechanical apparatus for 8 weeks. The duration of different postures: standing, ventral recumbency, lateral recumbency and frequency of standing periods were recorded as influenced by different environmental factors. 1. Floor with and without bedding at 21 degrees C. 2. Floor without bedding at 27 degrees C environmental temperature. 3. Feeding once daily versus twice. Duration of recumbency periods was increases at 21 degrees C if bedding was provided. This also improved daily gain. At elevated environmental temperatures the animals preferred the lying posture on concrete floor. Feeding twice increased the duration of recumbency. The same was the case as the animals grew older. Disturbance by caretaking activities in neighbouring dens increased the duration of standing.     

Effect of muramyl dipeptide on immunogenicity of Corynebacterium pseudotuberculosis whole-cell vaccines in mice and lambs

Colostrum-deprived lambs and CF1 mice were vaccinated with water-in-oil emulsion vaccines containing nonviable whole cells (WC) of Corynebacterium pseudotuberculosis with and without muramyl dipeptide (MDP). Efficacy of vaccines was determined from the survival of mice and lesions in lambs after IV injection of 10(4) colony-forming units of C pseudotuberculosis. In mice, protection was related to the concentration of WC in the vaccine. At 50, 100, or 150 micrograms of WC, protection was good (78.8%). At 10 or 25 micrograms of WC, protection was considerably less (54.7%). At high WC concentrations, protection could only be moderately increased to 82.3% with high (50 and 100 micrograms) concentrations of MDP or increased to 90% protection with low (5 and 10 micrograms) concentrations of MDP. At low WC concentrations, protection significantly decreased to 32% (P less than 0.025) with high concentrations of MDP, but significantly increased to 72.5% (P less than 0.025) with low concentrations of MDP. Therefore, the amount of protection with lower concentrations of WC and MDP was comparable with the amount of protection with higher concentrations of WC without MDP. In lambs, high prechallenge antibody titers (geometric mean titers from 5.1 to 5.4 by day 35) were observed after vaccination with WC. Protection and vaccination site abscesses in lambs were related to the concentration of WC and MDP. Pulmonary or vaccination site abscesses were not observed in 4 of 4 lambs vaccinated with 1 mg of WC + 50 micrograms of MDP.     

Effects of tail docking and castration on behaviour and plasma cortisol concentrations in young lambs

Behavioural and cortisol responses of lambs to the usual husbandry practices of castration and, or, tail docking using tight rubber rings were investigated between birth and seven days old. There were four treatments: control handling and blood sampling (n = 52), tail-docking (T) (n = 57), castration plus tail-docking (CT) (n = 54) and intravenous adrenocorticotrophin injection (ACTH) (n = 52). After treatment there was a transient rise in plasma cortisol concentration, the magnitude and duration of which increased in the following order; control, T, CT and ACTH. Behavioural characteristics indicative of distress included restlessness (standing up and lying down frequently, rolling, kicking, stamping), lateral recumbency, immobility with neck extension and hyperventilation. Using changes in cortisol concentrations and behaviour the lamb responses were characterised as reflecting 'mild disturbance without distress' (control, ACTH), 'mild distress' (T) and 'marked distress' (CT). The mild distress lasted for about 30 minutes in T lambs and marked distress for about 60 minutes in CT lambs.     

Cystic papillary meningioma in the sella turcica of a dog.

An 8-year-old spayed Scottish Terrier was examined because of a history of intermittent abnormal behavior that progressed to hind limb ataxia and eventually to recumbency with opisthotonos. X-Ray computed tomography revealed a radiolucent mass in the area of the hypothalamus. At necropsy, a suprasellar cystic papillary meni-ngioma was identified. The unusual clinical signs of disease and computed tomographic findings of this case complicated diagnosis.     

Effect of body position on oesophageal and gastric pressures in the anaesthetised dog

The effect of body position on lower oesophageal sphincter pressure (LOSP), gastric pressure and barrier pressure (BrP) was investigated in 40 dogs anaesthetised for neutering procedures. The dogs were placed in lateral recumbency followed by dorsal recumbency (group 1) or vice versa (group 2). LOSP decreased significantly in the animals which were positioned initially in lateral recumbency, when they were then placed in dorsal recumbency, while those initially positioned in dorsal recumbency showed no significant change in their LOSP or BrP when their position was altered to lateral recumbency. When the data from both groups were pooled, LOSP and BrP were significantly lower when the dogs were in dorsal compared to lateral recumbency (P<0–05).     

Copper toxicosis in lambs fed milk replacer

Thirty-four hysterectomy derived, crossbred lambs were fed a commercial, lamb milk replacer, containing added copper from birth. Twenty-five lambs died, four were killed and five survived. At necropsy, generalized icterus, enlarged kidneys and enlarged or small livers were found.     

Effect of body position on cranial migration of epidurally injected methylene blue in recumbent dogs

OBJECTIVE: To determine the relationship between different body positions during recumbency on the cranial migration of epidurally injected methylene blue in canine cadavers. SAMPLE POPULATION: 21 fresh cadavers of clinically normal adult female mixed-breed dogs. PROCEDURE: Dogs were randomly assigned to the following 3 groups: dogs remaining in right lateral recumbency (n = 7), dogs rotated from left to right lateral recumbency (7), and dogs rotated from dorsal to right lateral recumbency (7). Each dog received an epidural injection of 0.05% methylene blue (0.1 mL/kg) at the lumbosacral space. A dorsal laminectomy of the vertebral column was made, and cranial extent of methylene blue in 4 quadrants (right lateral, left lateral, ventral, and dorsal) was determined by examining dura mater staining. RESULTS: No significant difference was found among groups in regard to body weight or body condition score. Epidural cranial migration of methylene blue in the right lateral quadrant was significantly greater in dogs that remained in right lateral recumbency than in dogs that were rotated from left to right lateral recumbency. No significant difference was found within groups for epidural cranial migration of methylene blue between each quadrant. No significant relationship was found between body weight or body condition score and epidural cranial migration of methylene blue. CONCLUSIONS AND CLINICAL RELEVANCE: Body positioning and amount of recumbency time influence cranial migration of epidurally injected methylene blue. If greater cranial migration of an epidurally administered drug is desired, placing the patient in lateral recumbency with the surgical site on the dependent side may precede surgery.     

Efficacy of Corynebacterium pseudotuberculosis bacterin for the immunologic protection of sheep against development of caseous lymphadenitis

The efficacy of a Corynebacterium pseudotuberculosis bacterin to protect sheep immunologically against development of caseous lymphadenitis was evaluated in controlled challenge-exposure experiments. Sixty-three mixed-breed, white-faced lambs were used. The lambs were 10 to 12 weeks old and were randomly assigned to 3 groups (21 lambs/group). Group 1 was vaccinated once, using 2 ml of a C pseudotuberculosis bacterin (given subcutaneously) in the right axillary region at the beginning of the study. Group 2 was vaccinated twice; the 1st vaccination was given at the same time that lambs in group 1 were vaccinated and the 2nd vaccination was given 4 weeks later. Group 3 (nonvaccinated controls) was given physiologic saline solution (2 ml, subcutaneously). Each lamb was challenge exposed (ie, given 2 ml of live Corynebacterium pseudotuberculosis inoculum [6 X 10(6) colony-forming units/ml], subcutaneously at 4 different sites) during the 20th week of the study. All lambs were killed and necropsied during week 33. The mean number of abscesses per lamb was 7 for group 1, 4 for group 2, and 32 for group 3. Significant differences in the size of the abscesses were not found between the groups. Results of the study indicated that the vaccine provided immunologic protection of lambs against challenge exposure to Corynebacterium pseudotuberculosis.     

Clinical and microbiologic findings in lambs inoculated with Pasteurella haemolytica after infection with ovine adenovirus type 6

Colostrum-deprived lambs (10 to 20 days old) were inoculated with either ovine adenovirus type 6 (OAV-6; n = 6), Pasteurella haemolytica type A1 (n = 6), or OAV-6 followed by P haemolytica 5 days later (n = 10). Another group (n = 3) served as sham-inoculated controls. Lambs inoculated with OAV-6 or P haemolytica developed mild and moderate respiratory tract disease of 6 and 3 days' duration, respectively. Lambs inoculated with virus and bacteria developed clinical signs of respiratory tract disease of greater intensity and duration (9 days) than with either agent alone. Within 3 hours of bacterial inoculation, all lambs that received P haemolytica were anorectic, listless, and febrile, and had hyperpnea and dyspnea. Ovine adenovirus type 6 was isolated from all virus-inoculated lambs. Although P haemolytica was not recovered from all bacteria-inoculated lambs, it was recovered for a longer period in the group that received both agents. Antibody to OAV-6 was detected in virus-inoculated lambs as early as day 6 after inoculation. The control lambs remained clinically normal and neither virus nor bacteria were recovered at necropsy.     

INFLUENCE Of PATIENT POSITIONING ON THE L5–L6 MID-LAMINAR DISTANCE

The aim of this project was to determine the effect of patient position on the L5-L6 mid-laminar distance (MLD). The lumbar area of 22 recently euthanatized dogs of various breeds was radiographed in three positions: lateral recumbency with the spine in neutral position, lateral recumbency with the spine flexed in a kyphotic position, and sternal recumbency with the spine flexed in a kyphotic position. Digital images of the radiographs were analyzed using a computer program that allowed measurement of the MLD between L5-L6 in the three positions. The L5 and L6 MLD was significantly larger in sternal recumbency with the spine flexed (142.3 units) than both in lateral recumbency with the spine flexed (138.7 units; P= 0.001) and lateral recumbency with the spine in the neutral position (135.8 units; P < or = 0.001). The MLD in lateral recumbency with the spine flexed was significantly larger than in lateral recumbency with the spine in neutral position (P = 0.005). Positioning a dog in sternal recumbency with the spine flexed produces a significantly larger MLD than in lateral recumbency with the spine flexed; this should simplify needle placement when performing a lumbar puncture.     

Epidemiological features of Morel's disease in goats

Morel's disease caused by Staphylococcus aureus subsp. anaerobius was diagnosed for the first time in Poland in October 2006 in a goat flock. A second infected flock was found two months later. The course of the disease in both flocks was observed for 15-17 months. Clinical manifestation was confined to abscesses located near major superficial lymph nodes, mostly: superficial cervical, subiliac, parotid and mandibular. At necropsy no other lesions were found. The incubation period was estimated at 3 weeks. Clinical signs were seen both in young and adult goats and up to 7 abscesses in one animal were noted. Abscesses tended to persist for 1 to 5 months, then rupture and heal completely. The initial high in-flock point prevalence in both flocks (93.6% and 84.4%) dropped to approximately 10-30% during next 3-4 months. Until the end of the observation period the in-flock point prevalence remained at this level and only single abscesses were observed, mainly in young animals. No influence of the concurrent caprine arthritis encephalitis virus (CAEV) infection on the clinical course of Morel's disease was noticed. It is to be concluded that the clinical course of Morel's disease in a goat flock resembles caseous lymphadenitis (CLA). However, in Morel's disease abscesses occur more frequently in young goats and are located near, not inside, the lymph nodes, as in the case with CLA. Also, the incubation period of Morel's disease seems to be shorter (3 weeks versus 2-6 months in CLA).     

A Case of Wound Botulism in a Foal Affected by Gastric Ulcers in Italy

The case of a 50-day-old Thoroughbred foal affected by sudden muscular weakness and failure to swallow associated with recumbency is described. The clinical picture suggested a diagnosis of botulism. At necropsy, nonglandular gastric mucosa presented deep ulcerations. No other macroscopic nor microscopic lesions were detected. Clostridium botulinum type B was isolated from the lesions of gastric mucosa, whereas the cecal and colonic content, assayed for both spores and toxins, were negative. Moreover, analyses of all potential environmental sources of toxins near the feeding areas were negative. It was concluded that the colonization of gastric ulcers may have contributed to this unusual case of botulism. To the best of our knowledge, this is the first case of botulism in horses reported in Italy, which is also the first case anywhere of wound botulism caused by infection of gastric mucosa lesions.     

Experimental Corynebacterium pseudotuberculosis infection in lambs

Lambs were inoculated IV with 3.2 X 10(3) colony forming units (CFU) to 3.2 X 10(6) CFU of Corynebacterium pseudotuberculosis from a 6-hour broth culture supplemented with 0.1% sorbitan monooleate. After 28 days, multiple abscesses were observed in the lungs and lymph nodes. The number of abscesses in the lungs correlated with the inoculation dose. Two lambs given 10(5) CFU and 10(6) CFU died. Multiple abscesses occurred in other lambs given 10(6) CFU to 10(4) CFU and few abscesses occurred in lambs given 10(3) CFU. Corynebacterium pseudotuberculosis was isolated from lung abscesses, inoculation site abscesses, and lymph node abscesses, but not from normal tissues. Because this procedure consistently induced abscesses in the lungs, we believe it will be a suitable challenge system for studies on the prevention of caseous lymphadenitis in sheep.     

Suspect copper toxicity in an alpaca

An alpaca presented in lateral recumbency and subsequently died. On necropsy examination the liver showed severe, widespread, periacinar hepatocellular necrosis, staining positive to a rhodamine stain for copper. Hepatic copper concentration was elevated. Copper toxicity in the camelid is difficult to diagnose, since the classical hemolytic crisis is not observed.     

Cervical spinal chordoma with chondromatous component in a dog

A 7-year-old male Belgian Shepherd dog was presented with sudden onset of lateral recumbency and tetraparesis. At the level of the third cervical vertebra, magnetic resonance imaging demonstrated an intrameningeal and intramedullary mass lesion. The animal was subsequently euthanatized. A necropsy revealed a semitranslucent solid mass infiltrating dorsal and ventral dura mater and the spinal cord. Histologic examination revealed a lobulated pleomorphic mass, mainly resembling undifferentiated cartilage interspersed by spindle-shaped and polygonal cells with highly vacuolated cytoplasm (physaliphorous cells). Immunohistochemistry of the tumor cells demonstrated dual expression of vimentin and cytokeratin. Based on the histologic and immunohistochemical results, the diagnosis of a chordoma with chondromatous component was made.     

Cerebral malacia in a mule with ependymoma

Ependymoma is a rare tumour of the central nervous system that can vary in anatomical location and produce a broad range of clinical signs. Sporadically described in dogs, cats, cattle and horses, this disease has never previously been reported in a mule. This report describes a case of a 12‐year‐old mule showing neurological signs, including blindness, dysphagia, incoordination, sternal recumbency, depression, apathy and emaciation. Because of the worsening health conditions, the animal was subjected to euthanasia for humane reasons. At necropsy, an area of malacia in the right subcortical region of the frontoparietal area of the cerebrum and an ovoid, firm, grey, 2.4 × 1.0 × 0.7 cm nodule in the right lateral ventricle was observed. Histopathology revealed that the nodule was a densely cellular mass with cells arranged in nests and cords, formations of pseudorosettes with perivascular deposition of fibrillar eosinophilic material and the presence of a few lymphocytes. The cells had rounded and moderately hyperchromatic nuclei, punctate chromatin, distinct nucleoli, and indistinct cytoplasmic margins. Based on the histopathological features, the nodule was diagnosed as an ependymoma, a tumour considered rare, but that may be included in the differential diagnosis for diseases with neurological signs.     

RADIOGRAPHIC HEART-VOLUME ESTIMATION IN NORMAL CATS

Heart volume mensuration was evaluated on conventional radiographs from eight normal cats in different body positions using computed tomography (CT). Heart volumes were calculated from orthogonal thoracic radiographs in ventral and dorsal recumbency and from radiographs exposed with a vertical X-ray beam in dorsal and lateral recumbency using the formula for an ellipsoid body. Heart volumes were also estimated with CT in ventral, dorsal, right lateral and left lateral recumbency. No differences between heart volumes from CT in ventral recumbency and those from CT in right and left lateral recumbency were seen. In dorsal recumbency, however, significantly lower heart volumes were obtained. Heart volumes from CT in ventral recumbency were similar to those from radiographs in ventral and dorsal recumbency and dorsal/left lateral recumbency. Close correlation was also demonstrated between heart volumes from radiographs in dorsal/ left lateral recumbency and body weights of the eight cats.