WOLFF-LEHMANN STANDARD, SHOWING THE AMOUNT OF DIGESTIBLE NUTRIENTS REQUIRED PER 1,000 POUNDS LIVE WEIGHT FOR HORSES AT LIGHT, MEDIUM AND HEAVY WORK

ARMSBY STANDARD, SHOWING THE AMOUNt of DigestiBLE PROTEIN AND ENERGY REQUIRED PER 1,000 POUNDS LIVE WEIGHT FOR HORSES AT LIGHT, MEDIUM AND HEAVY WORK

Balanced ration.-Foods vary widely in composition and they also vary considerably from the composition of the animal body. To meet the needs of the animal it becomes necessary to mix the foods in the proper proportion, so that the digestible nutrients will correspond to the demands of the body. This is called balancing a ration. Skill in balancing a ration depends much upon our knowledge of the digestible nutrients contained in the more common foods. It is rather a tedious undertaking, however, as there is no mathematical formula, and we must add to or take from the trial ration until the desired standard is obtained.

Nutritive ratio.-Since the only source of the protein of the body is the protein of the food, this nutrient plays an important part in the balancing of a ration. So im

portant is this nutrient that rations are balanced according to the proportion of it they contain. Thus we have the nutritive-ratio, which is defined as the ratio between the digestible protein on the one hand, and the digestible

carbohydrates and

fats on the other hand. The nutritive-ratio is ascertained by multiplying the digestible fats by 24, adding the product to the digestible carbohydrates, and dividing their sum by the digestible protein.

Since the

fat contains more

energy than the

other nutrients, it is multiplied by 24 to reduce it to a carbohydrate equivalent.

The method of calculating the nutritive-ratio of corn, the digestible nutrients of which are, protein 7.8, carbohydrates 66.8 and fat 4.3, is as follows:

Nutritive ratio 1 : 9.8.-This means that for each pound of digestible protein in corn, there are 9.8 pounds of digestible carbohydrate equivalent.

Computing rations. To illustrate the method of calculating a ration for a given purpose we will assume the case of a horse weighing approximately 1,000 pounds and at light work. In order to compare the Wolff-Lehmann and Armsby standards we will take the same kind and amount of food in each computation. Let us choose from

Table VIII of the Appendix, 12 pounds of timothy hay, five pounds of corn and five pounds of oats. If we arrange these in a table and compute the digestible nutrients in each, according to the Wolff-Lehmann method, we get the following:

According to the Wolff-Lehmann standard (p. 331), this ration is deficient in protein and rich in carbohydrates, thereby giving a nutritive-ratio of 1: 10.4, instead of 17.0, as called for in the standard. According to this standard, the ration could be improved by the addition of one pound of linseed meal.

Let us use the same food and calculate a ration by the Armsby standard (p. 331) for a 1,000-pound horse at light work. Taking the composition from Table VII of the Appendix and arranging the nutrients and energy in a table, we get the following:

According to the Armsby standard this ration, although composed of the same kind and amount of food as before, is slightly too rich in digestible protein and considerably so in energy value. This serves to emphasize the statement that feeding standards should serve as mere guides, to be modified according to attendant conditions.

CHAPTER XXXIII

PRACTICAL HORSE FEEDING

In seeking to improve our horses, we must not underestimate the importance of generous feeding. Breeding and selection make success possible, but will fail unless we provide a sufficient supply of the most suitable foods to the horse at all ages and stages of development. Horse feeding is essentially different from the feeding of other farm animals. Because of the small size of the digestive organs a relatively small quantity of roughage and a correspondingly large amount of grain is demanded. Further, the kind of work to which horses are put calls for the least possible load in the digestive organs.

Regularity of feeding. The horse should be fed regularly and uniformly at all times. He anticipates the hour of feeding and becomes nervous if it is long delayed. He neighs and coaxes for his food with great regularity, and his system becomes accustomed to a certain order that must be followed. Sudden changes, even for a single meal, may produce more or less digestive disturbance. The working horse should be fed often, as undue fasting is followed by taking an excessive supply of food or by eating too rapidly, either of which are likely to result in digestive disorders.

Order of supplying grain, hay and water.-As the stomach of the horse is not large enough to hold the entire meal, the order of supplying grain, hay and water is of much importance. It is stated that the stomach of the horse must fill and empty itself two or three times for each meal. During the fore part of the meal the material is pushed into the small intestines almost as soon as it enters the stomach by the food which follows. while to

ward the end of the meal passage is slow and the digestion in the stomach is more perfect. This would lead to the conclusion that the bulky foods should be fed first and the more nutritious foods toward the end of the meal. This practice leads to the serious objection that the horse is anxious, nervous and unsatisfied until fed his grain, for which reason he is usually fed grain before hay.

Watering the horse.-A discussion of the order of supplying food should include the time of watering the horse. Many persons think that the horse should be watered. before feeding, while others are equally as certain that feeding should precede watering. This difference of opinion may be due to the fact that either method will sometimes result in digestive disorders. If the horse is watered before feeding he may drink to excess, which may cause digestive disorders and will surely affect the appetite, and he will not consume as much food as he otherwise would. On the other hand, if the horse is very thirsty and water is withheld until after feeding, he may not eat heartily and may drink so much water as to lessen his usefulness while at work.

The object to be attained is to water the horse so frequently that he will not become thirsty and, therefore, not drink to excess. To do this the work horse should be watered four times each day; perhaps better results would be obtained from watering six times. Little or no difficulty will be experienced if the horse is watered after breakfast, both before and after dinner, and before supper. Perhaps better results would be obtained if the horse was watered before breakfast and again after supper, thus making six times daily, as is the custom in many large stables.

Changing foods.-Sudden changes in the food are to be avoided, as the digestive system may not be able to accommodate itself at once to such, and digestive disorders follow. Such changes sometimes result in scouring, as when the horse is too suddenly transferred from