Enzootic ataxia in Red deer

The occurrence of enzootic ataxia in fanned Red deer is reported. This syndrome occurred in a young adult and a mature deer, and was characterised by ataxia, swaying movements of the hindquarters, often the adoption of a dog-sitting posture and, eventually, inability to use the hind limbs. Spinal cord demyelination and mid-brain neuronal degeneration were the main histopathological lesions. Copper levels of feedstuffs on the property were normal but blood copper levels of unaffected animals in the herd were low. The aetiology of enzootic ataxia in deer is possibly multifactorial, although copper deficiency is a common finding in affected herds, and copper supplementation appears to prevent its occurrence.     

Type II ostertagiosis in farmed red deer

A mild form of type II ostertagiosis was recorded in a group of 12, 22-month-old red deer stags, slaughtered in an abattoir in April 1989. The animals appeared clinically normal but they were light and in rather poor condition. Mixed ostertagid infections were present in very variable numbers. In the seven most heavily infected animals, 70 per cent of the worms were in the early fourth stage and assumed to be hypobiotic. In some animals the worms were maturing and in these there were lesions similar to those associated with bovine ostertagiosis.     

Blood biochemical reference values for farmed red deer

The activities and concentrations of 30 whole blood and plasma constituents including enzymes, substrates, electrolytes and vitamins were determined in samples from 91 clinically healthy farmed red deer (Cervus elaphus) hinds ranging in age from one to 15 years. The hinds were randomly selected from a herd maintained on a mixture of reseeded and permanent hill pasture at an experimental research station in north east Scotland. The results were analysed statistically and the calculated means, standard errors and tolerance intervals provide a basis for diagnostic clinical chemistry in red deer. The data are compared with data from earlier reports on blood biochemistry in deer and other livestock species.     

Osteochondrosis associated with copper deficiency in young farmed red deer and wapiti x red deer hybrids

Osteochondrosis is reported in association with copper deficiency in young red deer and wapiti X red deer hybrids on eight deer farms throughout New Zealand. On two farms, more than 30% of fawns were affected. Affected animals were lame, often had one or more swollen joints, and in some cases had an abnormal "bunny-hopping" gait or "cow-hocked" stance. Lesions were most common in the carpal, tarsal, stifle and hip joints, and were usually bilateral. Defects in articular cartilage ranged from loose flaps to complete separation with exposure of subchondral bone and the presence of cartilage fragments within the joint space. In advanced cases, the joints had features of degenerative arthropathy. Bilateral epiphyseolysis of the femoral head was observed in some severely lame deer. All deer with osteochondrosis had low serum and/or liver copper concentrations.     

Osteochondrosis associated with copper deficiency in young farmed red deer and wapiti x red deer hybrids

Osteochondrosis is reported in association with copper deficiency in young red deer and wapiti x red deer hybrids on eight deer farms throughout New Zealand. On two farms, more than 30% of fawns were affected. Affected animals were lame, often had one or more swollen joints, and in some cases had an abnormal “bunny-hopping” gait or “cow-hocked” stance. Lesions were most common in the carpal, tarsal, stifle and hip joints, and were usually bilateral. Defects in articular cartilage ranged from loose flaps to complete separation with exposure of subchondral bone and the presence of cartilage fragments within the joint space. In advanced cases, the joints had features of degenerative arthropathy. Bilateral epiphyseolysis of the femoral head was observed in some severely lame deer. All deer with osteochondrosis had low serum and/or liver copper concentrations.     

Dictyocaulus infection in farmed red deer (Cervus elaphus)

Post mortem examination of red deer calves on a deer farm situated on hill ground in north-east Scotland revealed infection by a lungworm morphologically similar to Dictyocaulus viviparus. Trials were conducted to monitor the natural development of D viviparus infection in red deer, to investigate the value of a commercial lungworm vaccine and to evaluate methods of treating clinical cases. The findings indicate that the syndrome may be less apparent in red deer than it is in cattle, protection might be gained by vaccination and that housing and medication provide useful therapy. The extent of clinical disease is likely to depend on the general health, bodily condition and nutritional status of the animals versus the weight of infection acquired from the pasture. However, various factors can affect both sides in this confrontation.     

Osteochondrosis, skeletal abnormalities and enzootic ataxia associated with copper deficiency in a farmed red deer (Cervus elaphus) herd

A red deer herd of 150 mixed-age hinds, 48 stags and 102 weaners was identified as severely copper deficient during an observational study of 15 deer farms in the lower North Island of New Zealand during 1992 and 1993. Severe lameness was observed in nine weaners in 1992 (8.8% prevalence) and 15 in 1993 (12% prevalence). Typical abnormalities included swollen hocks and carpal joints and outward rotation of hind legs with hocks touching. At postmortem examination, there were epiphyseal fractures of the femoral head, severe degenerative arthropathy of the coxo-femoral joints and erosions of cartilage in many other limb joints. Osteochondrosis was confirmed histologically. Concurrently, three adult hinds and one adult stag developed into-ordination typical of enzootic ataxia which was confirmed histologically. Blood and liver copper concentrations in untreated affected weaner deer ranged from undetectable to 16.0 micromol/l (mean 7.6 micromol/l) and 25 to 53 micromol/kg (mean 39 micromol/kg), respectively. Mean blood copper concentrations in unaffected weaners in March 1992 and 1993 were 5.3 micromol/l and 4.4 micromol/l, respectively. The mean blood copper concentration in seven hinds in September 1992, prior to onset of clinical signs of enzootic ataxia, was 1.5 micromol/l (range 1.0-2.4 micromol/l). At other times of the year, mean blood copper concentrations ranged up to 12.5 micromol/l in adults and 8.9 micromol/l in weaners before treatment began in 1993. Pasture analyses showed copper contents of 6-11 ppm in 11 samples collected during 1992 and 1993. Sulphur ranged from 0.18 to 0.37%, molybdenum from 0.51 to 3.56 ppm and iron from 130 to 2886 ppm. These measurements supported a diagnosis of secondary copper deficiency. Supplementation with oral oxidised copper wire particles was undertaken from December 1992, resulting in an improvement in blood copper concentrations in some classes of deer. No further clinical abnormalities have been observed.     

Intra-uterine transmission of paratuberculosis (Johne's disease) in farmed red deer

AIM: To determine whether intra-uterine transmission of paratuberculosis (Johne's disease) occurs in farmed red deer (Cervus elaphus) in New Zealand. METHODS: On four different farms, nine late-stage pregnant hinds with Johne's disease were slaughtered and samples were taken from them and their 10 fetuses. Samples of the hepatic, ileocaecal and mesenteric lymph nodes and the posterior ileum were collected from the hinds. The lung, liver, spleen, jejunum and ileum from the fetuses were sampled, as were the placentomes. Blood samples were tested using the 'Paralisa' test, a modified immunoglobulin G1 (IgG1) enzyme-linked immunosorbent assay (ELISA). Tissue samples were cultured using the BACTEC system, and fixed samples were sectioned and histological slides examined. RESULTS: All nine hinds and 9/10 fetuses (one hind had twins) were culture-positive for Mycobacterium avium subsp paratuberculosis (M. ptb). Six hinds had gross lesions of Johne's disease, while all hinds had characteristic histopathological lesions affecting the ileum, ileocaecal valve and associated lymph nodes. The only histopathological change observed in the fetuses was some mild inflammation in the lungs of one individual. Acid fast organisms (AFOs) were seen in histological sections of the lymph nodes and ileum of six hinds, and none were seen in tissues from the fetuses. These six hinds were Paralisa-positive, whereas the remaining hinds and fetuses were serologically-negative. CONCLUSIONS: These results confirm that there is a high risk of transmission of M. ptb from clinically affected hinds to their fetuses during pregnancy. CLINICAL RELEVANCE: Johne's disease is an increasingly important disease responsible for deaths in young red deer. Recognising the influence of intra-uterine transmission on the spread of this disease may be an important step towards improved control of Johne's disease.     

Risk factors for dystocia in farmed red deer (Cervus elaphus).

OBJECTIVE: To analyse data from a study of deer herd health and productivity to identify potential risk factors for the occurrence of dystocia. DESIGN: A 2-year longitudinal observational study of 14 red deer farms was carried out in New Zealand. About 2700 hinds were monitored each year for individual characteristics including body condition score (BCS), and reproductive performance. Grazing and calving management practices were recorded. During calving, farmers recorded calving difficulties (dystocia) that needed human assistance or caused the death of the hind. Risk factors potentially affecting the occurrence of dystocia were identified and analysed by multivariable statistical techniques. RESULTS: The percentage of hinds with dystocia was 0.52% (95% CI 0.32 to 0.78). Hinds with a post-winter BCS over 3.5 were 2.7 times as likely to experience dystocia as hinds scoring 3.5 or less. Given the same BCS class, bodyweight gain in late pregnancy was associated with an increased risk of dystocia. Grazing steep paddocks in the last trimester of pregnancy decreased the risk of dystocia in hinds with a BCS over 3.5. CONCLUSIONS: The risk of dystocia on red deer farms may be reduced if key individual animal, management and environmental factors are optimal.     

Parapoxvirus infections in New Zealand farmed red deer (Cervus elaphus)

Outbreaks of infection due to a parapoxvirus were reported on eight New Zealand deer farms. Scabby lesions were seen variably on the muzzle, lips, face, ears and neck of red deer (Cervus elaphus) with morbidity rates reaching 100%. On three farms multifocal lesions were also present on the velvet. Deaths were reported on two properties where the lesions were extensive and secondary bacterial infections had occurred. On one of these farms multifactorial disease was suspected. Poxvirus particles were seen by negative contrast electron microscopy in scab material from all eight properties. Morphologically the deer virus resembled a parapoxvirus, but restriction endonuclease analysis showed its DNA fragment patterns were distinct from those of orf (contagious ecthyma) virus.