March 2010 RVL Monthly Report
Kilkenny diagnosed adactyly (missing phalanges) in a full term still born calf. Phalanges II and III were missing from all digits in the hind limbs (Figure 1). A similar condition has been reported as a possible inherited defect in Southdown lambs.
Figure 1 Adactyly (missing phalanges) in a full term still born calf (photo Donal Toolan)
Coli-septicaemia associated with low immunoglobulin levels was diagnosed frequently by the various RVLs in calves under one week of age during the month. Dublin recorded a ZST of 10 (target 20) and isolated Salmonella dublin in a six day of scouring calf that was bottle fed colostrum. Sligo noted many full term calves presented during the month were dehydrated and had evidence of bruising and scleral haemorrhages, suggesting dystocia.
Limerick diagnosed septicaemic salmonellosis in a four-week old calf with a history of scour and weakness for five days before death. Salmonella dublin was isolated.
Kilkenny diagnosed several cases of salmonellosis, with various manifestations including pneumonia, navel infection, joint infection and enteritis. Hypogammaglobulinaemia was a predisposing factor in a number of cases.
Diffuse interstitial pneumonia due to BRSV and a severe localised subacute fibrinopurulent peritonitis involving the cranial abdomen was diagnosed by Dublin in a two-month-old calf. Kilkenny isolated Haemophilus somnus from a 6-week-old calf with a history of pneumonia.
Sligo diagnosed enzootic pneumonia in a three month old Belgian beef calf, where there was high level of mortality from pneumonia. There was extensive (80%) cranio-ventral consolidation of the lungs. It emerged that the calves were housed in a draughty shed, which predisposed them to pneumonia. Severe diffuse pleurisy caused by Mannhaemia haemolytica was diagnosed by Dublin in a three-week-old calf. Sligo diagnosed peritonitis emanating from omphalophlebitis in a two week old calf. Athlone isolated Staphylococcus aureus from the abdomen of a two week old calf with a florid fibrinoserous peritonitis with petechiae and ecchymotic haemorrhages. Again the umbilicus was the entry point for the infection. An intussception in association with enteritis caused by Salmonella dublin was diagnosed by Sligo in a three week old calf that died suddenly. The calf came from a large dairy herd which had not given its salmonella vaccine booster. A profound selenium deficiency was found by Sligo in dry suckler cows in a herd where calf health and immunity were compromised and cows were retaining their afterbirths.
Marked depletion of the bone marrow was diagnosed by histopathology in a two week old calf with a history of severe haemorrhage. On gross post mortem there was carcass pallor, melena (with a large clot in the anus), and evidence of profuse haemorrage from the injection site into the jugular vein and a wound on the dorsum. The calf had a BVD viraemia and septicaemia due to Listeria monocytogenes.
Limerick concluded carbohydrate overload led to death, inappetance and staggering in a group of ten yearling Friesian bullocks. The animals were normally fed with silage and rolled barley, mixed in a feeder wagon. However on one occasion to save time, the farmer carried the silage in with the front loader and emptied the usual allocation of rolled barley on top of the silage. The following day the animals were anorexic and staggering. The herd veterinary practitioner initiated intravenous and oral treatment for rumenal acidosis. At post mortem the rumen pH was found to be 4.1, confirming rumenal acidosis.
Marked hepatic fibrosis with adult fluke in the bile ducts was found in two nine month old emaciated weanlings submitted to Athlone. Four comrades had died in the recent past, and in light of the pathology seen further losses were anticipated.
Kilkenny isolated Pasteurella multocida in a 4-month-old pneumonic calf from an organic farm where six animals had wasted and died. Arcanobacterium pyogenes was isolated from a spinal abscess discovered in the lumbar area of a ten-month old euthanised weanling with a history of hind limb ataxia submitted to Limerick. Traumatic reticulo pericariditis was uncovered in a two year old pregnant heifer with a history of abdominal pain presented at Athlone. A piece of wire was found that had penetrated the reticular wall and set up the infection.
Malignant Catarrhal Fever was diagnosed on histo-pathological examination of the brain of a two year old cow with a history of nervous signs submitted to Athlone.
Athlone examined six bovine animals ranging in age from 6 days to 13 months which had a perforated abomasal ulcer with resulting diffuse peritonitis. The clinical histories indicated sudden deaths or death after a short clinical course. One three week old calf was reported to have a scour prior to death. In two cases Clostridial soredellii was detected, using fluorescent antibody test, in oedematous wall of the abomasum adjacent to the perforation (Figure 2). Only in one of the cases were the rumen contents as acidic with a pH of 5.6.
Figure 2 Oedematous and necotric abomasal wall adjacent to perforated abomasal ulcer (photo John Fagan)
Kilkenny diagnosed listeriosis by histological examination of the brain of a ten-year-old cow that was inappetant, dull and had nervous signs. Abomasal ulcers were diagnosed by Sligo in two cows found dead from the same holding. Enteritis, haemorragic enteritis, inappetance and reduced milk yield were among the presenting signs of cows diagnosed with Salmonella dublin presented to Killenny. Reddening of the mucosa of the caecum and small intestine and the anti-mesenteric serosa of the small intestine were seen in a three-year-old cow submitted to Kilkenny diagnosed with Salmonella typhimurium enteritis.
Kilkenny diagnosed Johnes' Disease by isolation of organism from an animal that was negative on gross and histological examination. The animal had a high positive Johnes' ELISA result.
Kilkenny isolated Escherichia fergusoni from the milk, mammary gland, supramammary lymph node and liver of a two year old cow with toxic mastitis.
Kilkenny diagnosed chlamydial abortion (Enzootic Abortion of Ewes, EAE) in two flocks in different counties. Kilkenny isolated Salmonella dublin and Streptocococcus uberis from each of a pair of aborted severely decomposed twin lambs. Salmonella arizona was isolated on a single occasion from an aborted lamb.
Omphalogenic hepatic necrosis and abscessation with peritonitis were diagnosed in a three-week-old lamb submitted to Dublin, Figure 3, the third lamb affected in the flock. Streptococcus agalactiae and Arcanobacterium pyogenes were isolated from the liver.
Figure 3 Omphalogenic hepatic necrosis and abscessation in a three-week-old lamb (photo Ann Sharpe)
Braxy was diagnosed by Dublin as the cause of sudden death in a six-week-old lamb, several of whose cohorts had died, where the abomasal wall was emphysematous and thickened diffusely. The timing of vaccination of ewes relative to the risk of disease was being investigated. Advice was given to house sheep on frosty nights and feed hay prior to turnout the following day. Pulpy kidney disease was diagnosed by Athlone in a three week old organic lamb from a flock in which vaccination was not practiced.
Sligo diagnosed listeriosis by histopathology in a four year old ewe with history of nervous signs including dribbling saliva and paralysis of the lower jaw. Acute necrotising mastitis caused by Staphylococcus aureus was diagnosed by Dublin in a ewe found dead.
Copper toxicity was diagnosed by Athlone in a ram which had died suddenly. There was a strong ammonia like odour from the carcase, the kidneys were grey in colour and the bladder was distended with urine which was very turbid. The kidney and liver copper level were markedly elevated.
Sligo found chronic fluke and strongyle infestation in two ewes with serosainguinous fluid in the abdomen, serous fluid in the thorax and multiple adult fluke in the gall bladders of both, Figure 4. Chronic fasciolosis was diagnosed as cause of death in several ewes and a hogget from different premises submitted to Kilkenny.
Figure 4 Adult fluke in the gall bladder of a ewe with chronic facioliasis (photo Damien Barrett)
Athlone diagnosed Black Disease, in association with significant liver damage arising from fluke infestation in two hoggets vaccinated on the evening prior to death.
Peracute fibrinous bronchopneumonia with a fibrinous exudate was found in a three-week-old kid submitted to Dublin. A pure culture of Mannheimia haemolytica was isolated. This illness had been preceded by an outbreak of diarrhoea in the flock.
Cork received a buzzard (Buteo buteo) from east Cork. The buzzard was in excellent condition. The cause of death was an ingested gizzard, possibly that of a chicken of seven to eight weeks, which had lodged in the oesophagus and caused perforation of the wall of the oesophagus. Cork noted an increase in the incidence of right sided ventricular heart failure (RVF) in broilers, causing ascites and oedema, in flocks of varying size.
Dublin diagnosed fowl cholera in five chickens from a broiler unit, which had an increased mortality problem. Most of the broilers had a fibrinous polyserositis and Pasteurella multocida was isolated from all cases.
Limerick found fibrinous pleutitis, pericarditis and pneumonia in two ten-week old pigs with a history of sudden death. Histophilus somnus was isolated from both pigs.
A pure growth of haemolytic Escherichia coli (Abottstown O148) was isolated by Dublin from the intestines of two 26-day old pigs from a unit where pigs were dying quite quickly after becoming ill.
Limerick found a lymphosarcoma (diagnosed on histopathology) in the mesentry of an old donkey that died suddenly as a result of haemorrhage from the tumour.
Kilkenny isolated Pasteurella bacteria in an 8 year-old alpaca with right sided heart failure, as a result of valvular and mural endocarditis. It presented with brisket oedema, hydrothorax, and ascites.