December 2, 2010

US research shows late coccidiosis challenge affecting bird performance

US researchers have discovered that coccidiosis challenge late in the production cycle of chickens has a serious, negative effect on energy utilisation, flock performance and profitability.

It takes place although coccidial gut lesions are minor, according to researchers.

"I have never conducted a nutrition study with the order of magnitude that this study revealed about the impact of intestinal health on energy utilisation," Dr. Robert Teeter, of Oklahoma State University, said.

His findings indicate that when broilers encounter a coccidiosis challenge late in the production cycle, they use more energy and need more feed in contrast to birds challenged with coccidiosis early in the production cycle. The result is increased malabsorption, reduced effective caloric value and an elevated maintenance cost, Teeter said.

The researcher and his team measured the effect of coccidial lesions on energy utilisation, also known as the "calorific cost," with the aid of indirect calorimetry chambers. His lab at the university has 60 of the chambers and is the largest set for small animals in the world. The chambers allow measurement of values such as oxygen consumption and carbon dioxide production in real time as birds are exposed to various stressors such as coccidiosis.

Teeter also uses an X-ray densitometer (DEXA) unit to scan birds noninvasively and measure protein, fat, water, ash, and energy content. "This technology gives us a complete picture of what is happening with growth and performance," explained the nutritionist.