Epidemiological and pathological studies on congenital diffuse hyperplastic goiter in calves

Area of Science:

• Veterinary Pathology
• Animal Nutrition
• Reproductive Medicine

Background:

• High incidence of perinatal diseases (weak calf, stillbirth, abortion) observed in cattle at A Farm during 1987-1988.
• Pathological examination of stillborn and weak calves revealed significant thyroid abnormalities, including diffuse hyperplastic goiter.

Purpose of the Study:

• To investigate the impact of seaweed supplementation in maternal feed on perinatal diseases and thyroid health in calves.
• To identify potential etiological factors contributing to goiter and associated reproductive issues in cattle.

Main Methods:

• Comparative pathological examination of thyroid glands from calves before and after seaweed supplementation.
• Histological assessment of thyroid tissues for hyperplastic goiter.
• Analysis of iodine content in pasture grasses and identification of potential goitrogenic plants (Rorippa indica) in affected farms.

Main Results:

• Seaweed supplementation led to a significant decrease in perinatal diseases and thyroid goiter incidence.
• Thyroid glands from calves before supplementation showed marked goiter (67%), while those after supplementation showed no lesions (0%).
• Higher prevalence of goiter was noted in calves from A Farm compared to B Farm, correlating with lower iodine levels and presence of Rorippa indica.

Conclusions:

• Seaweed supplementation is effective in mitigating perinatal diseases in calves, likely by addressing nutritional deficiencies or goitrogenic factors.
• Goiter in calves is strongly associated with adverse perinatal outcomes and may be linked to marginal iodine deficiency and plant-induced thiocyanate exposure.
• Dietary management, including seaweed and careful pasture selection, is crucial for preventing goiter and improving reproductive health in cattle.