Feeding livestock during and after a disaster can present livestock owners and producers with a host of challenges. This is due, in part, to unfamiliar feeds that are donated or sourced from outside the region of the emergency. Having a basic understanding of the nutrient requirements of your animals and their digestive systems, as well as the characteristics of individual feeds, is the foundation on which to build an emergency feeding program. Feed analysis is the most effective way to accurately balance an animal’s diet, which may be of increased importance after a stressful event, such as a disaster. In addition, being able to effectively transition animals to unfamiliar feeds and identify potential toxicities will go a long way in keeping animals healthy during times of stress.
Feeding Considerations for Monogastric vs. Ruminant Animals
In the event of a disaster, livestock may need to be fed feedstuffs that are available rather than what has normally been fed. However, quickly changing the diet can be stressful for livestock and lead to digestive issues if not done properly. Different species of livestock will have different nutrient needs based on their digestive systems and stage of production (i.e., age, growth, gestation, lactation). If alternative feeds are to be utilized, it is important to understand the nutrient content and any risks associated with each feed so that digestion problems can be avoided. Perry et al. (2003) provide insight into the differences between monogastric and ruminant animals and how those differences relate to overall nutrient requirements and feeding strategies.
Pigs cannot utilize fiber, like ruminants or horses, so their diets are made up of mostly concentrates. Swine are fed concentrate diets in all phases of production. They need a high-energy, low-fiber diet with a moderate amount of protein. Nutritional needs will vary based on stage of production. The National Swine Nutrition Guide provides a source with tables on nutrient recommendations for swine in all stages of production.
Like pigs, chickens do best when fed high concentrate diets. Their beaks allow them to sort through feed very well, so pelleted feed is usually preferred. If pelleted feed is not available, a mash feed with small particle size (2–3 mm) should be fed. Similar to swine, chickens require moderate-protein, high-energy diets. Energy concentrates may make up to 75% of the diet. Calcium is a critical part of diets for laying hens as it is needed for eggshell formation. The National Research Council’s (NRC) Nutrient Requirements of Poultry gives nutrient requirements for multiple classes of poultry and stages of production.
The microorganisms in the rumen of cattle allow them to digest and obtain most of their energy from roughages (forages and hay). However, these microorganisms are sensitive to change. If the diet changes from a high roughage to a high concentrate without adequate time for the animal to adjust, digestive upsets can occur. If forage is limited, concentrates may make up to 90% of the diet, but cattle require roughage for proper rumen function. Cattle must be transitioned to a high-grain diet gradually or digestive disturbances can occur. Depending on stage of production (i.e., gestation, lactation) protein may need to be supplemented in forage-based diets to meet requirements. Protein also helps improve digestion of low-quality hay and other forages, more information about this can be found in WSU Extension publication EM053E Feeding Beef Cattle I: The Realities of Low-Quality Forages.
The NRC’s Nutrient Requirements of Beef Cattle presents the nutrient requirements for beef cattle of many different types, sizes, and stages of production. The NRC’s Nutrient Requirements for Dairy Cattle is available for free download as well.
Small Ruminants/Pseudo-Ruminants (sheep, goats, llamas, and alpacas)
Small ruminants and pseudo-ruminants, like cattle, are also prone to digestive upsets if major diet changes occur. Hay/forage will comprise most of their diet; however, in some cases they may need supplemental protein similar to cattle (Wieland and Noldan 2011; Van Saun 2016).