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Others cause more generalised disease with abortion being the result of '''septicaemia''': ''Salmonella typhimurium'', ''Salmonella dublin'', [[Tick-Borne Fever|tick-borne fever]] (''Erlichia phagocytophila'').

Others cause more generalised disease with abortion being the result of '''septicaemia''': ''Salmonella typhimurium'', ''Salmonella dublin'', [[Tick-Borne Fever|tick-borne fever]] (''Erlichia phagocytophila'').

Other bacterial agents include: ''Campylobacter fetus fetus'', ''Campylobacter jejuni'', other ''Salmonellae'' species, ''Listeria monocytogenes'', ''Leptospira interrogans'', ''Coxiella burnetti'' (Q fever).

Other bacterial agents include: [[Campylobacter fetus subspecies fetus|''Campylobacter fetus fetus'']], ''[[Campylobacter jejuni]]'', other [[Salmonella|''Salmonellae'' species]], ''[[Listeria monocytogenes]]'', ''[[Leptospira]] interrogans'', ''[[Coxiella burnetti]]'' (Q fever).

Viral agents include '''Border Disease Virus'''.

Viral agents include '''[[Border Disease Virus]]'''.

Other protozoa include ''Neospora caninum''.

Other protozoa include ''[[Neospora]] caninum''.

Finally, fungal organisms such as ''Aspergillus fumigatus'', ''Claviceps purpurea'' and various mycotoxins have also been involved in cases of abortion.

Finally, fungal organisms such as ''[[Aspergillus spp.|Aspergillus fumigatus]]'', [[Ergot Poisoning|''Claviceps purpurea'']] and various mycotoxins have also been involved in cases of abortion.

==Investigation of an Outbreak==

 

 

==Investigation of an outbreak==

A positive diagnosis of an infectious cause only results with material from about '''50% of incidents''' submitted to veterinary diagnostic laboratories, but it does not follow that the remaining 50% are not due to infections. Materials submitted may not have been suitable, the wrong test carried out, or fragile organisms may not have survived the journey to the laboratory.

A positive diagnosis of an infectious cause only results with material from about '''50% of incidents''' submitted to veterinary diagnostic laboratories, but it does not follow that the remaining 50% are not due to infections. Materials submitted may not have been suitable, the wrong test carried out, or fragile organisms may not have survived the journey to the laboratory.

===Information gathering===

===Information Gathering===

Often, little can be done to halt an outbreak once it has begun, and abortion occurs weeks or months after an infection has been acquired.

Often, little can be done to halt an outbreak once it has begun, and abortion occurs weeks or months after an infection has been acquired.

A detailed history should be taken, including details about the flock such as management, husbandry, abortion history, recent events. Also details of the abortions seen so far such as timing of abortions, clinical signs in the ewes, which ewes are affected, appearance of the aborted foetus, isolation of the affected ewes.

A '''detailed history''' should be taken, including details about the flock such as management, husbandry, abortion history, recent events. Also details of the abortions seen so far such as timing of abortions, clinical signs in the ewes, which ewes are affected, appearance of the aborted foetus, isolation of the affected ewes.

===Submission of samples for investigation===

===Submission of Samples for Investigation===

All aborted material should be retained by the farmer, and samples should be taken from the freshest case. Ideally, material should be submitted from every abortion, or at least from 10% of affected ewes.

'''All aborted material should be retained''' by the farmer, and samples should be taken from the freshest case. Ideally, material should be submitted from every abortion, or at least from 10% of affected ewes.

Care should be taken as some of the agents present a '''zoonotic risk''' to the farmer and workers involved.

Care should be taken as some of the agents present a '''zoonotic risk''' to the farmer and workers involved.

===Laboratory tests===

===Laboratory tests===

'''Gross  findings''' may suggest a possible aetiology for the abortion, such as the thickened placenta seen in Enzootic Abortion of Ewes or the white pinhead lesions on the cotyledons due to ''Toxoplasma'' infection. However several other disease may mimic these signs and diagnosis should not be made on gross pathology alone.

'''Gross  findings''' may suggest a possible aetiology for the abortion, such as the thickened placenta seen in enzootic abortion of ewes or the white pinhead lesions on the cotyledons due to ''Toxoplasma'' infection. However several other diseases may mimic these signs and diagnosis should not be made on gross pathology alone.

Several tests can be used to determine any infectious agents involved. This includes '''Ziehl-Neelsen staining, gram staining, cultures of placenta and foetal stomach contents and foetal serology'''. Virus isolation, PCR and histopathology can also be performed if no diagnosis is reached in the preliminary investigation.

Several tests can be used to determine any infectious agents involved. This includes '''Ziehl-Neelsen staining, gram staining, cultures of placenta and foetal stomach contents and foetal serology'''. Virus isolation, PCR and histopathology can also be performed if no diagnosis is reached in the preliminary investigation.

==Steps to take following an abortion==

==Steps to Take Following an Abortion==

Aborting ewes should be '''marked''' for later identification and sampling, and '''isolated''' from other sheep.

Aborting ewes should be '''marked''' for later identification and sampling, and '''isolated''' from other sheep.

The bedding and abortion products should be disposed of and the area '''disinfected thoroughly'''.

The bedding and abortion products should be removed and the area '''disinfected thoroughly'''.

'''Antibiotic therapy''' can be initiated if the ewe is unwell or has retained foetal membranes.

'''Antibiotic therapy''' can be initiated if the ewe is unwell or has retained foetal membranes.

Lambs should not be fostered onto ewes that have aborted due to the risk of Enzootic Abortion of Ewes.

Lambs should not be fostered onto ewes that have aborted due to the risk of enzootic abortion.

'''Good hygiene and biosecurity''' should be maintained to avoid zoonotic disease.

'''Good hygiene and biosecurity''' should be maintained to avoid zoonotic disease.

Mearns, R. (2007) '''Abortion in sheep: Other common and exotic causes''', ''In Practice'' 29: 83-90

Mearns, R. (2007) '''Abortion in sheep: Other common and exotic causes''', ''In Practice'' 29: 83-90

[[Category:To Do - Helen]]

 

[[Category:To Do - Review]]

[[Category:Reproductive Diseases - Sheep]]

[[Category:Expert Review - Farm Animal]]