Abstract

Clinical cryptosporidiosis is a gastrointestinal disease commonly observed in neonatal calves, with well-known acute symptoms. However, the long-term production consequences of this parasitic infection on affected calves have received less attention. This article explores the lasting effects of clinical cryptosporidiosis on newborn calves, shedding light on the often overlooked "ripple effect" that impacts their future productivity and overall profitability for farmers. The article discusses the impact of cryptosporidiosis on growth and weight gain, the development of malnutrition and weakened immunity, increased mortality rates, higher veterinary intervention and treatment costs, as well as reduced future productivity. Understanding the extended ramifications of clinical cryptosporidiosis is crucial for implementing proactive management strategies to mitigate its impact. By addressing the long-term effects of this disease, farmers can enhance the well-being and profitability of their livestock operations.

The disease is caused by Cryptosporidium spp. and is one of the most common causes of calf enteritis in the UK. The parasite is very difficult to remove from the farm, as the oocysts have a tough outer wall which enables the parasite to survive for several months in moist temperate environmental conditions and it is difficult to kill oocysts with common disinfectants used on a farm. If appropriate management practises are applied, the disease is usually self-limiting and most calves will recover. It has been shown, in studies with children and in lambs, that severe clinical cryptosporidiosis can result in long-term growth and cognitive impairment compared with individuals with no obvious signs of the disease. This study measured the long-term growth rate of beef calves on farm by comparing groups of animals that had suffered differing degrees of clinical severity of cryptosporidiosis as neonates.