Health is extremely important in ensuring high sheep reproductive rates. Any health issue, such as reproductive diseases, worm burdens, liver fluke or footrot, will slow weight gain or cause weight loss resulting in lower reproductive rates.
Prevention and early detection
An important part of basic animal welfare is keeping animals free from disease and producers should take measures to test, monitor and, where necessary, treat sheep showing the affects of disease.
Many reproductive diseases present similar symptoms, such as abortion and perinatal lamb mortality, and producers suspecting the presence of such a disease should consult a veterinarian. The early detection of any diseases, especially new, emerging or exotic diseases, is the key to their effective management.
Infectious reproductive diseases
Infectious reproductive diseases that can lead to significant economic loss include:
Producers should ensure that their breeding flock is fully vaccinated against likely diseases and manage external livestock introductions to minimise the risk of infection.
Nutritional reproductive diseases
Nutritional diseases can be caused by specific nutrient deficiencies, excesses or imbalances, or by metabolic disturbances. Nutritional reproductive diseases that can lead to significant economic loss include:
- Hypocalcaemia (milk fever)
- Ketosis (pregnancy toxaemia)
- Mineral deficiencies (phosphorus)
- Perennial ryegrass toxicoses
Producers should be aware of the nutritional requirements of their flock throughout the reproductive cycle and ensure that an appropriate level of nutrition is available to maintain good body condition and support reproductive function. Where a shortfall is identified, supplementary feeding should be undertaken to prevent reproductive diseases.
Feed budgeting can be useful in predicting and managing nutritional short falls.