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5.4 Feed Adaptation Problems

5.4.1 What Are The Feed Adaptation Problems?

Animals entering the export process have diverse feeding and management histories and often have little or no prior exposure to pellets. This may cause animals to adapt poorly to the unfamiliar feed, water and delivery systems within the export process. Many animals unfamiliar with pellets and troughs will start eating pellets from troughs immediately, while others may require time (days or even weeks), and some never adapt. Nutrition theory suggests it may take weeks for the rumen microflora to adapt fully to a major dietary change such as from pasture to pellets.

5.4.2 Situations Leading To Feed Adaptation Problems

Animals that may be slower to adapt to export diets include:
  • Those not previously exposed or adapted to pellets or feeding from troughs, particularly semi-domesticated animals from extensively managed production systems (compared to animals accustomed to handling).
  • Those coming from lush pasture (compared to animals coming from areas where feed quality is low).
  • Older animals compared to younger animals (possibly because appetite is greater in younger, growing animals).
Some of these animals may begin eating then develop indigestion from a sudden change in protein, energy and digestibility of the diet. Engorgement, to which younger, growing animals with large appetites are especially prone, may cause some to succumb to diseases of overeating such as acidosis, bloat and enterotoxaemia. Some animals may voluntarily choose not to eat the pellet diet and fall into the category of shy feeders or persistently inappetent animals.

5.4.3 Detection Of Feed Adaptation Problems

Inspection of troughs for uneaten feed is best done after feeding and care should be taken to allow sufficient time for animals to finish eating. 

Adaptation problems may be detected by observing animals closely for signs of inappetence during routine inspections. The slow-to-adapt categories of animals mentioned above deserve special monitoring. Inappetence from non-adaptation will be evident from day 1 of the voyage. Feed will remain uneaten in troughs, and animals may be described as “hollow in the flanks”, “tucked up” or “slab sided”. Single animals to whole pens may be affected. Note that there may be considerable amounts of uneaten pellets in feed troughs in the first few days of a voyage as animals adapt to the ship environment. Amounts of uneaten feed should decline as animals adapt. 

Be aware that inappetence may also occur during periods of heat stress, when respiratory or other diseases are incubating or occurring, or when there has been a reduction in feed quality. A feature distinguishing these from adaptation problems is a sudden onset of non-eating in animals that have been previously eating well.

5.4.4 Interventions And Prevention Of Feed Adaptation Problems

When individual animals are not eating, and adaptation problems are suspected, they may need relocating to other pens that are cooler, quieter and better ventilated, and less densely stocked with other similarly affected (and preferably similar sized) animals. The greater trough space, reduced competition from pen mates, reduced stress and the special provision of increased amounts of appetite-stimulating hay and chaff often result in animals resuming eating. 

Animals may adapt more quickly to shipboard life and feeding if they are left alone for the first day or two after loading. It may be beneficial to limit activities in this period to essential adjustments to relieve overcrowded pens and treatment of injured animals. 

Animals may be enticed to eat unfamiliar feeds from unfamiliar receptacles by laying hay and chaff over the pellets, or mixing chaff in with the top layer of pellets. This may be especially important for older animals to reduce the number of shy feeders, and should start as soon as they are on board. The location, height and number of feed troughs may need adjusting to ensure easy access.