The North Coast of NSW is not a major sheep or goat production area. However, the peri-urban section of the region contains a large number of small holdings that can have interesting combinations of species including both small ruminants and others. The form of agriculture practiced in this peri-urban environment can have biosecurity, welfare and food safety concerns. This case study provides an example of a disease investigation where goats were being used in combination with a horse enterprise.
In early April 2012, the North Coast LHPA made a farm call to a horse owner in Lismore who also had goats on his property. These goats were feral goats that had been caught in western NSW and were then transferred to the small Lismore property. The owner was using these goats for 6-8 weeks to train his cutting horses before the goats were sold direct to slaughter. At the time of the visit there were approximately 30 goats on the farm. These goats had not yet been sent to slaughter after the intended 6-8 weeks and had been on the farm for close to 12 weeks.
The owner had become concerned with the health of his goats as several of them were having breathing difficulties, scours and six had died. On the advice of a local private veterinarian the goats had been prescribed a pencillin based antibiotic, an oral benzimidazole drench and an oral ivermectin drench. The drenching had improved the scours in some of the goats but deaths still occurred.
The group of goats was examined from a distance and a recumbent goat was examined in detail. The goats were observed to be in poor body condition and over 30% were scouring. The recumbent goat was reluctant but able to stand, had mild respiratory difficulty, nasal discharge, black hard faeces and mucous membrane pallor. The rectal temperature was 35.8 degrees celcius.
The recumbent goat was euthanased and a necropsy was performed. Necropsy findings included: minimal omental fat, ascites, red-grey diffuse discolouration of the cranioventral lung lobes, caudal lung fields pink in colour with a clear demarcation to the abnormal cranioventral lung fields, cranioventral lungs cut surface oozed purulent exudates, fibrinous material connected the pleural surface of the craniovental lung fields to the thoracic wall and a moderate number of live Haemonchus worms in the abomasum. A tentative morphological diagnosis was made of severe, subacute fibrinous pleuropneumonia. Associated with this was helminthasis and hypoproteinaemia.
Samples of the consolidated lung were taken for histopathology and bacterial culture. A histopathological section of disease lung highlighted airways filled with suppurative exudates and alveoli filled with fibrin, neutrophils and other inflammatory material. Scattered bacterial colonies and a necrotic region were also observed. Bacteriology cultured a profuse predominant growth. This was identified as Streptococcus sp. (alpha-haemolytic). The tentative diagnosis of severe, subacute, suppurative bronchopneumonia was confirmed.
Disease on this property was found to be due to a combination of nutritional, parasitic and infectious causes. These goats were not suited to the North Coast environment having originated from the drier western region. The nutrition available on the property was not sufficient to provide enough nutrients, especially protein, to the goats. The land was overstocked and feed was both short and of poor quality. The wet moist conditions favoured the pasture survival of Haemonchus which contributed to the hypoproteinaemia and anaemia. These goats were not being drenched regularly or effectively. The decision to retain the goats for longer than the 6-8 weeks without adequate nutrition or drenching greatly contributed to the disease outbreak. The hypoproteinaemia would have led to a reduced ability to deal with secondary infections such as the pneumonia which was seen in the recumbent goat. Similar respiratory signs had been seen in other goats on the property.
The bacterial culture of Streptoccocus sp. was not considered to be the primary pathogen as it was subsequently learnt that the recumbent goat had been treated with antibiotics prior to sampling.
A management plan was provided to the owner. Ideally rotational grazing would have been recommended however, this would not have been possible on this property due to limited size. The owner was advised that for future batches of goats he should not retain them for longer than 8 weeks. It was important to give advice that would allow correct adherence to withholding periods whilst still addressing the preventative health needs of the animals. The producer is going to try the use of a number of different chemical actives given at the same time (combination drenching) 3 weeks after a batch of goats arrive and then wait out any necessary withholding periods before sending them to slaughter. It was also recommended to feed the goats a more nutritious food source such as hay and commercial goat pellets or goat muesli.
These measures should improve the welfare of these goats, food safety, and the ability of the producer to utilize the animals to help his horse enterprise.