Veterinary Services

Cobalt deficiency (pine), hypocuprosis and hyposelenosis were diagnosed in flocks in Ayrshire and Argyll, mainly in growing lambs.  In one Ayrshire flock pine was considered to be a predisposing factor to parasitic gastroenteritis, causing ill-thrift and diarrhoea. In an Argyllshire flock hypocupraemia was associated with a dramatic fall in lambing percentage amongst Scottish blackface and Scottish mule sheep. Gimmers and young ewes were particularly affected. Abortion serology showed no evidence of potential abortefacients. Hyposelenosis was associated with a poor lambing percentage in an island hill flock in Argyllshire.

Toxic conditions

 
A sample of liver was received at Dumfries after three of a group of six Lleyn lambs died.  The group were fed cattle cake and the carcase appeared jaundiced.  The liver copper content of 17,800 umol/kg dry matter (DM) (reference range 314 to 7850 umol/kg DM) confirmed the diagnosis of copper poisoning.

Parasitic diseases

The relatively warm September weather, following very wet months in July and August provided ideal conditions for the development of nematode larvae and multiplication of the dwarf pond snail, Galba truncatula, favouring high levels of challenge with Fasciola hepatica metacercariae. 

Parasitic gastroenteritis (PGE) once again represented the commonest diagnosis of the month. In one Ayrshire hill flock some gimmers in a group of 200 were noted to be pining following summer grazing, despite anthelmintic and flukicide treatments.  Postmortem examination of two gimmers presented alive revealed chronic enteritis consistent with PGE and parasitic pneumonia with high faecal nematode egg counts. Hyposelenosis and vitamin B12 deficiency were also evident and considered to be predisposing factors.  Anthelmintic resistance could not be ruled out and further investigation was initiated.

Chronic fasciolosis was also diagnosed on 20 occasions.  Concurrent chronic fasciolosis, PGE and parasitic bronchitis were diagnosed in a group of scouring tups in an Argyllshire island flock on the basis of high faecal trichostrongylid egg counts and the presence of F. hepatica eggs and lungworm (Dictyocaulus filaria) larvae. Elevated blood liver enzyme values indicated significant hepatocellular and hepatobiliary damage in affected animals.

Haemonchosis was diagnosed in a flock of 700 Swaledale ewes and their lambs in the eastern Borders of Scotland. Total worm counts carried out on two carcases were 4,600 and 9,600 Haemonchus contortus worms within the abomasum, and 5,900 and 1,300 of mixed Cooperia and Trichostrongylus species worms respectively in the small intestine. Gross findings included emaciation, diarrhoea, myiasis on the brisket and a limited number of ticks.  Both carcases were pale and the blood was watery. Post-drenching efficacy tests carried out by the private veterinary surgeon suggested benzimidazole (BZ) anthelmintic resistance. The mean trichostrongylid worm egg count for the group treated with BZ was 990 eggs per gram (epg) before drenching and 1600 epg after drenching, consistent with resistance to this class.  No further deaths occurred after drenching the group with ivermectin and the lambs are now reported to be thriving.

Several outbreaks of nematodirosis and PGE were also recorded by St Boswells.  Two outbreaks were associated with severe cobalt and selenium deficiency in an organic enterprise with  an easycare flock and Katahdin flock, the latter being a fleece shedding breed originally developed in the US during the 1950s..  Over three weeks, 10 of 100 seven-month-old lambs died within the Katahdin flock and 25 of 600 of four to five-months-old lambs died deaths in the easycare flock.  Scour and dramatic weight loss was seen earlier. At necropsy, emaciation, signs of severe PGE and Dyctyocaulus filaria in the airways were recorded.  Abomasal worm counts as high as 10,000 Teladorsagia species and intestinal worm counts of 12,000 Nematodirus battus were recorded. 

In an Argyllshire flock five-month-old lambs were reported to be scouring and losing condition despite anthelmintic treatment.  Pathogenic coccidial oocysts (E. crandallis and E. ovinoidalis) were detected in both faecal samples submitted.  Coccidiosis with secondary renal tubular degeneration and suppurative bronchopneumonia was evident on postmortem examination of two lambs submitted from an Ayrshire flock.

Alimentary tract disorders

A tentative diagnosis of Listeria ivanovii septicaemia was made in two female Suffolk lambs aged four months, from a group of 900 lambs on heavily grazed pasture.  At least 12 deaths occurred over a period of 10 days, preceded by weight loss, scour and weakness.  Benzimidazole resistance was considered to be present on the farm and the group was treated with ivermectin six days before.  However the history and gross findings strongly suggested PGE and the detection of 300 Teladorsagia species worms in the abomasum supported this opinion. In addition to these findings L. ivanovii was isolated from the ileum and viscera. Further, copper deficiency in one lamb (liver copper 135 µmol/Kg dry matter (DM); reference range 314-7850 µmol/Kg DM), severe cobalt deficiency (liver vitamin B12 <0.07 µg/g wet material (WM); reference range >0.19 µg/g WM) and selenium deficiency (liver selenium 0.175 mg/g DM; reference range 0.90-3.50 mg/g DM) in both lambs were detected.  SAC C VS considered that whilst Listeria ivanovii was the ultimate cause of death in these lambs, this was a consequence of the parasitic gastroenteritis and deficient micronutrient status. SAC C VS advised a post-dosing efficacy check for all three class of wormer and a review of grazing management. 

Two ewes were received at Dumfries from a farm with an increase in flock mortality.  Swelling around the jaws was also noticed.  In both cases there was necrosis and cellulitis within the pharynx.  Haemorrhage was evident with blood clots in the rumens and the carcases were pale.  The ewes were drenched two weeks earlier with ricobendazole and the findings were consistent with a dosing gun injury.  Both ewes had a worm egg count of 1,050 trichostrongylid worm epg indicating that the treatment had not been successful. 

Johne’s disease (paratuberculosis) was diagnosed in a three-year-old golden Guernsey nanny-goat from an Argyllshire island herd. The affected animal was thin and had soft faeces.

Reproductive tract conditions

Serological evidence of tick borne fever was obtained in a Dumfriesshire flock where earlier this year no diagnosis was achieved despite many submissions of aborted foetuses.  In total 25 of 85 ewes of mixed ages aborted on one section of hill. Abortions occurred during April from two weeks after the ewes were turned on to this ground.  Some ewes were reported to be depressed with a dirty vaginal discharge after aborting, but none died.  The abortions occurred from up to four weeks before lambing was due to start.  The blood samples collected from the aborted ewes were seropositive for tick borne fever, while ewes that had not aborted gave either borderline positive or negative results.  Occasional ticks had been seen in previous years, but were not considered to be a significant problem on the holding.  The area of land where the problem occurred was no longer grazed by cattle.  It had become more overgrown than usual, creating ideal conditions for tick survival.

Nervous system disorders

Listerial encephalitis was confirmed in a two-year-old female British alpine goat with a five-day history of lethargy, anorexia, head tilt with drooping ear, and tremor. The goat reportedly had access to poor quality hay.  Listeria monocytogenes was isolated on direct culture from the brain.

Skin diseases

Samples were received at Dumfries from a group of ram lambs described as having pruritic scabby lesions and hair loss on their faces.  Trichophyton verrucosum was isolated on dermatophyte culture.  Myiasis (blowfly strike) was diagnosed as the sole cause of clinical signs and deaths in a group of 11 ewes on a farm in Sutherland.