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Ruminal digestion relative to the digestion in the remainder of the gastro-intestinal tract accounts for about 70 to 85% of the total digestion of dry matter (Annison, 1956). Phillipson (1958) showed that losses of digestible materials via absorption between the mouth and the duodenum were approximately 70% of that total. The interpretation of rumen composition and digestion data is complicated by several factors, such as dilution with materials remaining from previous feedings, inflow of saliva, variations in flow rate of the different nutrients and the time of sampling af ter feeding, (Yadava et al., 1964; Yadava and Bartley, 1964; Gray, Pilgrim and Weller, 1958a,b).The objectives of these experiments were to: 1. Determine the effects of the type of feed and the time of sampling after feeding on the concentration of selected nutrient fractions in the rumen; 2. Calculate the total digestion of the feed as determined by lignin vs.chromic oxide feed/feces ratios and; 3. Estimate the extent of total dry matter digestion accounted for by ruminal fermentation and absorption.

Experiments were conducted to study the influence of adrenalectomy, with minimal replacement therapy, on mating behavior and embryonic mortality in thermally stressed mature ewes. Group I ewes were adrenalectomized and maintained post-operatively with 20 mg hydrocortisone and 5 mg deoxycorticosterone daily, with Group II ewes being intact. All ewes were mated and immediately placed in a 32.2 C temperature controlled room for 5 days. They were then removed, slaughtered, and the reproductive organs and intact adrenals collected.Reproductive performance was not statistically influenced by adrenalectomy as measured by percent mating, ovulation, fertilization, and conception rate. When the three replications of the experiment were pooled, the number of viable embryoes was significantly reduced in the intact ewes compared to the adrenalectomized ewes (P<.07). The stressed intact ewes were found to have statistically heavier (P<.01) adrenal weights than those removed from the surgically operated ewes before heat treatment.

A chromatographic method for the determination of cobalt in feeds is described. The ashed sample is dissolved with HCl, filtered, and the filtrate evaporated to dryness. Perchloric acid is added and the contents evaporated to white fumes. With the addition of distilled water and nitroso R salt, the cobalt complex color is developed in the usual manner. The entire solution is passed through a perchloric acid-washed alumina column. The cobalt complex is adsorbed on the column. The excess reagent is eluted from the column with dilute HNO3. The cobalt complex is then eluted with dilute H2SO4, and determined colorimetrically.Advantages over previous methods are that copper and iron do not interfere with the cobalt determination, and larger initial samples may be ashed to give a greater concentration of cobalt in the final solution for a colorimetric determination.As determined by this method, the cobalt content of hays range from 0.047 to 0.468 p.p.m., cereal grains from 0.014 to 0.091 p.p.m., and plant protein concentrates (sunflower, cottonseed, and linseed meal) from 0.190 to 0.500 p.p.m.

1.Cobalt supplementation increased significantly the rate of gain in growing-fattening swine.2.Addition of 5% meat scraps to a corn-soybean meal type ration increased significantly the rate of gain; the greatest increase was noted in the pigs which also received cobalt.3.Inclusion of excellent quality dehydrated alfalfa as 5% of the ration depressed significantly the rate of gain of growing-fattening pigs.

Two experiments designed to study the protein requirements of pregnant ewes are reported. Six lots of twenty ewes each were included in each experiment. In the first experiment rations which contained approximately 7, 10, and 13 percent total crude protein were compared and in the second rations containing 5, 8, and 11 percent protein.No statistically significant differences were found between the various rations in fleece weight, birth weight of lambs, or weight of lambs at thirty days of age. Some trends were noted, however, in that the ewes fed the lowest levels of nitrogen tended to shear lighter fleeces and their twin lambs weighed slightly less at thirty days.The death loss of ewes was somewhat higher on the low-protein rations. The low nitrogen intake may have been a predisposing factor in a number of these deaths.Nitrogen balance experiments showed no significant differences in nitrogen retention between the three levels of nitrogen intake during early and mid gestation. In late pregnancy the ewes fed the higher levels of nitrogen retained significantly larger amounts.A highly significant correlation (r=0.69) was found to exist between nitrogen retention and digestible dry matter intake. Covariance analysis showed that, at the levels fed in these investigations, the amount of nitrogen stored was influenced more by the amount of dry matter digested than by the amount of nitrogen fed.The results obtained indicate that present recommendations with respect to amounts of crude protein for pregnant ewes may be decreased when the rations fed are adequate in other nutrients.

A rapid, simple and accurate method has been presented for the determination of the wool fiber diameter. This method makes use of the audio oscillator and a vibrascope constructed from a “2” inch permanent magnet speaker. With this apparatus, the frequency is obtained at the maximum vibration of the wool fiber. The diameter of a vibrating wool fiber then can be calculated from the following equation:Where D is the diameter of the wool fiber in microns, T is the tension in grams: d is the density of the fiber; L is the length in cm. and V is the frequency in cycles per second.This method has been found useful for evaluating the quality of individual fleeces in a selection program, designed to reduce variability in fiber diameter.

A reversal of wool pigmentation from white to black and vice versa has occurred in Hampshire sheep fed rations low in vitamins A and D.Vitamin A treatments to depleted sheep of Hampshire origin brought no response in pigmentation pattern.A reversion to original wool pigmentation was noted when vitamin D was administered to lambs previously treated with vitamin A.Sheep of Delaine-Merino × Rambouillet ancestry or Columbia-type sheep that were heterozygous for black showed no pigmentation reversal pattern.There was a difference between Hampshire lambs in their response to rations deficient in vitamins A and D.

Stilbestrol, implanted as a pellet subcutaneously, did not consistently stimulate gains of growing-fattening pigs as with beef cattle and lambs.The non-treated controls required from 5.2 to 13.7% more feed per hundred pounds gain than did the treated pigs.Treatment of gilts with the levels used is not to be recommended because of prolapse of the uterus as a result of the stilbestrol.Stilbestrol treatment caused teat development in both sexes, a mild nymphomaniac response and extreme swelling of external genitalia of gilts, and in barrows, a restored ability for erection and renewed sex desire.Subcutaneous implantation in the ear is not to be recommended because of greater chance for encapsulation or cyst formation around the pellet in that area.

The results of four experiments are presented. There were no consistent differences in lamb production from ewes fed rations approximately equal in total digestible nutrients but which varied from 6.8 to 11.0 percent total protein. There were no apparent differences in production between ewes fed linseed meal or dried skimmilk as a protein supplement to a grass hay, shelled corn ration.Pregnant Shropshire ewes averaging 135 pounds in body weight remained in positive nitrogen balance, made satisfactory gains and gave birth to thrifty lambs when fed an average of 0.10 pound digestible protein per ewe daily. No improvement in utilization of protein or production was noted from the addition of 0.10 percent DL methionine.Further work is needed relative to the protein requirements of pregnant ewes.

A total of 992 blood samples of pregnant ewes fed various kinds and amounts of protein were analyzed for oxyhemoglobin, total serum proteins, serum albumins and serum globulins. Considerable variation was found in these constituents between individual sheep and between bi-weekly samples from the same ewe.Ewes fed rations low in protein had lower serum albumins than those fed a liberal or adequate amount of protein. Low protein rations also caused a reduction in oxyhemoglobin. Serum globulins were not affected by the rations fed.When fed at an equal level of protein there were no differences in blood proteins between ewes fed linseed meal and those fed dried skim milk as the protein supplement.Ewes with high oxyhemoglobin levels tended to have high serum albumins and low serum globulins. In these experiments serum globulins predominated over serum albumins. The oxyhemoglobin, total serum protein and serum globulin levels of individual ewes were highly correlated between years.