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Trials were conducted to evaluate effects of non-enzymatic browning of soybean meal (SBM) on efficiency of protein utilization and N digestibility. In trial 1, 48 Suffolk-Finnsheep lambs (22 kg) were fed 80 d to evaluate efficiency of protein utilization for growth when supplemental protein was fed as urea (U), commercial SBM (CS), or commercial SBM (pH 8.5, 83% dry matter) containing xylose (3 mol/mol SBM-lysine) and heated 30 min (XTS-30) or 55 min (XTS-55). Diets containing graded levels of N from CS, XTS-30 and XTS-55 were fed. Response criterion was efficiency of protein utilization, plotted as gains of lambs fed test proteins minus gain of lambs fed U vs supplemental test protein fed. Efficiencies of protein utilization were .62, 1.27 and .91 for CS, XTS-30 and XTS-55, respectively. Protein from XTS-30 was used more efficiently (P<.05) than that from CS. In trial 2, apparent digestibility of N from CS (97%) was higher (P<.01) than XTS-30 (77%) and XTS-55 (82%) by Suffolk-Finnsheep lambs (27 kg). In trial 3, 60 mixed-breed steers (218 kg) were fed individually for 105 d to evaluate glucose as a reducing sugar. Glucose-treated SBM (GTS) was prepared by mixing glucose (3 mol/mol SBM lysine) with SBM, adjusting pH and dry matter content to 8.5 and 80%, respectively, and heating at 150 C for 60 min. Supplemental N sources were U, CS, GTS and a 50:50 mixture (protein basis) of corn gluten meal and blood meal (CGM/BM). Efficiencies of protein utilization were .90, 1.91 and 1.85 for CS, GTS and CGM/BM, respectively. Efficiency of protein utilization of GTS was higher (P<.05) than CS but not different (P>.10) from CGM/BM. In trial 4, apparent digestibility of N from CS (100%) was higher (P<.05) than GTS (93%) by Suffolk-Finnsheep lambs (40 kg). These results are interpreted to indicate that controlled, non-enzymatic browning improved efficiency of soybean protein utilization by ruminants.

Non-enzymatic browning was tested as a means of suppressing degradation of soybean meal (SBM) by ruminal microbes in five trials with in vitro ammonia release as the response criterion. Treatments imposed on SBM included reducing sugar source (xylose, glucose, fructose and lactose), reducing sugar level (1, 3 and 5 mol/mol SBM-lysine), pH (6.5, 8.5 and 10.0), dry matter (DM) content (65, 70, 75, 80, 85 and 90%) and varying lengths of heating time ( 0 to 90 min) at 150 C. Samples heated under conditions that promoted non-enzymatic browning gave greater (P<.01) ammonia release suppression that when SBM was heated without these treatments. Xylose was the most reactive sugar, but extended heating of SBM containing glucose, fructose or lactose resulted in ammonia release similar to xylose. Increasing sugar level from 1 to 5 mol/mol SBM-lysine caused linear decreases (P<.01) in ammonia release for xylose, glucose and fructose, but not lactose. Ammonia release was higher (P<.01) at pH 6.5 than pH 8.5 and 10.0, and higher (P<.01) at pH 9.5 than pH 10.0. Rate of non-enzymatic browning decreased when samples containing greater than 80% DM were heated. These results are interpreted to show that controlled non-enzymatic browning may be effective for reducing ruminal degradation of SBM.

Two factorial experiments were conducted to investigate site and extent of organic matter (OM) digestion, nitrogenous fractions flowing at the abomasum and rates-of-passage in steers fed 0, 2 or 4 g NH3/100 g dry matter of treated corncobs supplemented with either a corn or a blood meal-corn gluten meal (BM-CGM) supplement. Rumen and total tract OM digestion coefficients were quadratically increased (P<.05) and dietary N was quadratically increased (P<.07) due to the main effect of ammonia. The main effect of protein supplement increased (P<.05) postruminal OM digestibility, nonammonia N and dietary-N flow. Quadratic protein × ammonia interactions were noted for fluid flow, total-N flow, total amino acid flow and ammonia-N flow. Linear protein × ammonia interactions were noted for bacterial-N flow, which appeared to indicate that N utilization of the ammoniated corn-cob was improved by the inclusion of BM-CGM in the diet. Diet dry matter intake, fluid volume, rate of fluid passage, particulate mass and rate of particulate passage in rumen-fistulated steers were unaffected by either main effect. However, rumen fluid pH of steers fed BM-CGM was lower than that from steers fed the corn supplement.

Estrus was induced during March and April in 50 lactating ewes that were 20 to 31 d postpartum. Following estrus induction, ewes were treated with either saline or human chorionic gonadotropin (hCG; 100 IU) on d 11, 12 and 13 after mating. Regardless of whether ewes were later diagnosed as pregnant or not, treatment with hCG increased serum progesterone concentrations compared with concentrations observed in saline-treated ewes on d 12, 14 and 16 after mating (P<.01). Pregnancy rate was higher in ewes treated with hCG than that of ewes treated with saline (58 vs 29%; P<.05). Data from the present study indicate that it is possible to increase pregnancy rate in lactating, anestrous ewes after artificially-induced estrus by administering hCG.

An experiment was conducted to determine the effect of source of pig, housing system and receiving diet on performance of purchased feeder pigs. Pigs purchased from distant auction markets (DM) gained slower for the first 13 d post-arrival (P<.01, trials 1 and 2) than pigs of similar size purchased from local, one-owner sources (LS). In trial 1, LS feeder pigs gained faster (P<.01) from purchase to 93 kg than DM pigs. In trial 2, the DM pigs were more efficient in feed conversion than LS pigs (P<.01). The DM pigs required more medical treatments than LS pigs (P<.01). In trial 1, pigs housed in mechanically ventilated, partially slatted-pen facilities gained faster (P<.1) than those in nonmechanically ventilated facilities whereas in trial 2, the reverse was true (P<.05). Pigs housed in the nonmechanically ventilated facilities had a higher incidence of scours (P<.01, trials 1 and 2) than those housed in the mechanically ventilated facilities. Death loss was less (P<.01) for pigs in the nonmechanically ventilated facilities (trial 2). Pigs fed a 16% crude protein receiving diet for 13 d containing 20% oats had a poorer (P<.01) feed efficiency than those fed a corn-soy basal diet or a diet containing 20% oats plus 5% lard (trial 1). At the termination of both trials, there were no differences in rate of gain or feed to gain ratio between the three receiving diets. Feeding diets containing 20% oats had no effect on the incidence of post - arrival scours but death loss was less (P<.1) for pigs fed the receiving diet containing 20% oats (trial 1).