Physiological Correlation with Feeding Preference

Physiological status is defined as the state or level of physiological function that the animal is in; for example the most common physiological states are maintenance, growth, gestation, lactation, working and geriatric. Each physiological status has different nutrient requirements to meet the functions of the body. Those states that have the highest nutrient requirements are late gestation, early lactation and growth. It should be emphasized again here that camelids are extremely efficient. Also, you will see animal variation – some are “easy keepers” and look at food and become obese. Other animals are “poor keepers” and will need dietary supplementation merely to maintain weight.

Maintenance

Maintenance is defined as where an animal’s weight is maintained – the animal is neither gaining nor losing weight. We often see this with studs outside of the breeding season, geldings that are not working or mature non-pregnant females. Since these animals are so energy efficient, just keeping them in a grazing situation with mineral supplementation is more than adequate – no grain is needed. If the pasture is lush and has a lot of plant growth, the animals may still become fat, thus limited grazing or feeding a forage at 1% of body weight is advised. Forage is the key to camelid management, and in fact, if the diet does not contain at least 25% crude fiber, animals will develop gastric ulcers. Forage usually has less energy than grain, and an animal will not be as hungry on a forage diet. Grain supplementation is rarely needed in a maintenance scenario. Monitoring body condition score is essential to prevent “fat” animals. As an added note, geldings have a lower energy requirement than intact males and females.

Growth

Growth involves the young cria as it is growing. Growth involves the building of body structure and will require a higher protein requirement (12-14%) than what is needed for maintenance (8-10%). Initially the cria will acquire its nutrients from its dam’s milk. As with other mammals, immediately after birth, a newborn cria must consume 10% of its body weight daily in colostrum. If llama colostrum is not available, goat colostrum may be used. Within 7 to 10 days, the cria will begin to mimic its mother’s example of grazing, though full rumination does not occur for several months. Creep feed is not usually necessary unless the dam has a limited milk supply. Regular weighing of the cria will enable you to monitor this. If milk does seem to be limiting, a leafy forage like alfalfa serves as a good creep feed; but if grain is used, crias need to be vaccinated for enterotoxemia. The cria is usually weaned at four to six months of age. Animals can be weaned as early as two months, but a much higher plane of nutrition is needed (16-18% CP and 60% TDN). Irrespective of when the animals are weaned, it is a stressful time for the young animal, and a higher plane of nutrition is warranted during the transition.

Gestation

Gestation is the period when the female is bred, and the embryo begins to develop. The gestation period is roughly 350 days. Of those 350 days, the first two trimesters or early pregnancy is where females often become obese – often because of the “extra care” from their owners. In the first trimester or 3.5 months, the female can be maintained on a maintenance diet unless she is lactating. If she still is nursing, obviously additional nutrients are needed. When the cria is weaned, a maintenance diet alone is sufficient. During the second trimester the female will gradually begin to increase her intake of forage, and seldom are supplemental grains necessary. The last 3 or 3.5 months of gestation, the third trimester, is when 90% of fetal growth occurs. Now, a small amount of grain can slowly be added into the diet twice a day (for example one pound twice daily for female llama). This level of grain can also be continued for the first three months of lactation to meet the needs of milk production. A word of caution again – each animal is different – some will need more and some will need less – use regular body condition scoring as a monitor. Most female llamas gain 45-60 pounds during gestation, while alpacas gain on average 20-30. As with all physiological stages, don’t allow the animal to become fat, as the added fat can result in birth complications.

Lactation

The dam usually reaches peak milk production three weeks after birth of the cria. Because of this, the female’s nutrient requirements are higher at this time. Again as indicated above, a small amount of grain should be fed until the third month of lactation. After that time, a gradual decrease in the amount of grain will allow for lower milk production and a gradual “natural” weaning process. It should be cautioned again that the females should not be allowed to become overweight. One of the first places fat is deposited is the mammary gland, and there is a potential for decreased milk production in the future Work. Again, emphasizing that every animal is different and that their body condition score needs to be monitored, animals under intense work (packing) need more energy. A hard working pack animal may have twice the energy requirement that it would have for maintenance. During these times grain should slowly be added into the diet – the amount of grain increased to provide 25-50% more energy. Caution should be taken if an animal is working under high heat and humid condition to prevent heat stress.

Geriatric

How animals adapt to their advanced years is as variable as people. In some, there is little change, while others age very quickly – again a good reason to regularly body condition score and weigh animals. Older camelids actually have a lower energy requirement  than younger animals. But by closely monitoring your animal, even subtle changes can be caught early. In general, with age we see compromised strength in an animal’s muscles and bone structure (joints) and often arthritis attacks the joints. The best thing to do for an older animal is to ensure that in the heat of the summer, shade or a cool place is provided. Older animals are more susceptible to heat stress as they have a lower sweat gland activity. When temperatures are colder, a heated barn and warmed water provide comfort for the animal. Warmed water is particularly important, as with other species, cold and icy water can result in decreased water consumption. Decreased water consumption can result in decreased feed intake and resultant weight loss. Also, as part of the aging process, gut function and motility is slowed, the chance of colic or an impaction occurring is higher. Monitor the animal to ensure that it visits the dung pile, or as an older animal it could be compromised very quickly. With age, we see a lowered immune function in all species. Thus alleviating stressful conditions can aid in immune function.