Kenaf Shows Potential as a Finishing Diet for Lambs

Can a crop grown to make paper be used to feed animals? Agricultural Research Service scientists say yes, based on their studies in El Reno, Okla.

ARS nutritionist William A. Phillips and colleagues at the Grazinglands Research Laboratory in El Reno compared two crops as a roughage source in the finishing diets of lambs. One was kenaf (Hibiscus cannabinus L.), a relatively new crop to the United States. The other, alfalfa (Medicago sativa), is the most commonly grown U.S. hay crop.

A member of the hibiscus family, kenaf is related to cotton and okra and does well in many parts of the United States. Although not widely grown here, it has been grown around the world as a source of fiber. In the United States, kenaf has been cultivated primarily for pulp in papermaking.

Previous research at El Reno has shown kenaf could replace alfalfa pellets, a commonly used protein supplement in sheep and cattle diets, as a crude protein supplement for lambs fed bermudagrass or fescue hay, without affecting feed intake or gain. The researchers used the lambs as an experimental model for cattle and concluded that the same response would be likely in cattle.

In the most recent project, 53 spring-born lambs were randomly assigned to pens and fed one of two different diets. Each diet contained 86 percent corn, nearly 6 percent molasses, more than 1 percent limestone and ammonium chloride, and 5 percent of either ground alfalfa hay or ground kenaf hay. Data from the study showed kenaf hay can replace alfalfa hay in the finishing diets of lambs without significantly affecting feed intake or performance.

Alfalfa is a perennial legume used in high-concentrate diets fed to lambs and cattle to provide protein and dietary fiber. To produce alfalfa, farmers must make a multi-year commitment of land and resources that is not always optimal for some integrated cropping-livestock enterprises. In some cases, unconventional annual crops like kenaf would provide producers with more flexibility than a perennial crop--including the option of marketing kenaf as a livestock feed or a source of fiber.

ARS is the U.S. Department of Agriculture’s chief scientific research agency.