Six experiments were carried out with Single Comb White Leghorn laying chickens to assess the effect of feeding a source of direct-fed microbials (Lactobacillus; Lacto) and its carrier [condensed cane molasses solubles (CCMS)] on the retentions of fat, nitrogen and several minerals; on the status of the pH of the gastrointestinal (GI) tract; on the phytase activities in the Lacto and in the crop and in the intestinal contents and intestinal, pancreatic and liver tissues; on the histological and anatomical changes of the GI tract and on the production performance. Feeding 1,100 mg Lacto/kg diet (ppm) and 2,200 ppm Lacto in corn-soya bean meal (C-S) diets to layers stimulated appetite, improved egg production (in Experiment 1 only), egg mass, egg weight, egg size, internal egg quality and fat, nitrogen, calcium and phosphorus retentions (P < .05). Production performances were not different between the layers fed the 1,100 ppm diet and those fed the 2,200 ppm Lacto diet. Supplementing Lacto diets with 1 and 3% fat reduced feed consumption, provided better feed conversion, egg production, egg masses, egg size, body weight gains, and nitrogen, calcium and phosphorus retentions. Feeding 1,100 ppm Lacto barley-corn-soya bean (B-C-S) layer diets improved body weight gains and the retentions of fat, phosphorus and manganese and increased the rate of passage of digesta (P < .05). Feeding Lacto C-S and Lacto B-C-S layer diets increased cellularity of Peyer's patches in the ileums of the layers which may stimulate the mucosal immune system. No changes in length and weight of the intestine were observed. Daily feed consumption and body weight gains were improved when pullets were fed 1,100 ppm Lacto from 7 to 19 wk of age (WOA). When these pullets were continued on the Lacto feed during the laying period (20 to 59 WOA), increased feed consumption, egg size, nitrogen and calcium retentions, increased cellularity of Peyer's patches, decreased length and weight of intestine were observed (P < .05). Presence of phytase activity was higher in condensed cane molasses solubles (CCMS)- Lactobacillus premix than the carrier (CCMS). Feeding the CCMS-Lacto diets to layers decreased the pH of the GI tract, increased phytase activities in the GI tract and intestinal tissues and improved shell thickness and phosphorus retention (P < .05). The production performance of layers fed .45% and .25% available phosphorus (AP) diets were not different except for body weight gain. Phosphorus retention was better for layers fed diets containing .25% AP with CCMS-Lacto than the .45% AP control diet. According to these studies, feeding Lacto to pullets and layers improved their performance and the retention of nutrients such as calcium, phosphorus and nitrogen which subsequently reduced the cost of feeding. / Graduation date: 1994

Monensin was fed at levels of 0 and 33 ppm in a series of experiments to determine its effect on nitrogen (N) utilization by steers fed diets high in sorghum grain (76%, steam-processed, flaked) and corn (90%, whole shelled). Total ruminal volatile fatty acid (VFA) concentrations measured 3 hr postprandially were not affected by monensin addition to either diet. Molar proportion of acetic acid decreased (P < .05) was observed with monensin addition to the sorghum grain-based diet. Monensin had no effect on apparent total tract digestibility of dry matter or energy in either diet, but consistently improved apparent total tract digestibility of crude protein (CP) in both diets. Improvement was greater (P < .05). Retention of N tended (P > .05) to improve in response to monensin with the sorghum grain-based diet (24 vs 20% of N intake; 41 vs 36% of N absorbed). Ruminal ammonia concentrations measured 3 hr post-prandially were decreased (P < .10) ruminal digestion of feed N (44 vs 51%) for steers fed monensin. Monensin decreased (P < .05) the contibution of bacterial N (42 vs 50%) and increased (P < .05) that of ruminally undegraded feed (bypass) N (58 vs 50%) to total N digested postruminally, resulting in less (P < .10) bacterial N (23 vs 28 g/day) and a tendency (P > .10) for more feed bypass N (32 vs 27 g/day) to be digested in the intestines of steers fed monensin with the corn-based diet. That monensin caused a greater proportion of feed OM and N to be digested and absorbed in the intestines than in the rumen (with possibly greater resultant metabolic efficiency) may account for some of the benefit of feeding this compound with high grain diets, as losses incurred in the ruminal transformation of feed nitrogen to bacterial nitrogen appear to be partially eliminated.

No description available.

The influence of microbial phytase on growth performance, availability of macro and trace minerals, apparent ileal digestibility (AID) and apparent "fecal" digestibility (AFD) of amino acids (AA) and CP were investigated. The optimum level of dietary Ca and P for the maximum efficacy of supplemental phytase in broiler chickens was also studied. Phytase supplementation (600 U/kg) to a low P diet increased $(P 0.05)$ on feed efficiency in broiler chickens at 21 d. The efficacy of phytase, particularly in stimulating growth, was higher in male than female chickens. The relative retention of Ca, P, Cu, Zn and N increased by addition of phytase to a low P diet but phytase had no effect $(P >0.05)$ on the retention of Mg, Mn and Fe. Phytase supplementation increased $(P 0.05)$ on plasma Zn, Cu, and Mg. Phytase increased $(P 0.05)$ on mineral proportions in the tibia ash; however, it increased $(P 0.05)$ on AID of any of the AA in male chickens. Addition of phytase did not have any effect $(P > 0.05)$ on AFD of any of the AA in male chickens but increased $(P 0.05)$ on either AID or AFD of CP and AA at 21-d. In summary, phytase supplementation increased the growth performance, availability of P, Ca, Cu, Zn and N, plasma P, and tibia ash and reduced plasma Ca; it also increased the AID and AFD of most of the AA, particularly in female chickens at 28-d. The efficacy of microbial phytase was high when dietary P and Ca levels were low.

No description available.

Raspberry pomace, consisting of seeds, pulp and added rice hulls, is the residue from the pressing of raspberries for juice and concentrate production. Through the determination of chemical composition by laboratory analyses and the measurement of feeding value in animal trials, the pomace was evaluated as a feedstuff for growing pigs. Pomace contains 11.1% crude fat, 10.0% crude protein, 59.5% total dietary fibre, 7.4% soluble carbohydrates, and a gross energy level of 5220 kcal*kg⁻¹. The acid detergent residue of the pomace contains 11.7% lignin, 6.0% cutin, 2.2% acid detergent ash and 26.0% cellulose (by difference). The digestibility of dry matter, fat, protein and energy was determined. Pomace dried at 60 C, whole and ground (1mm) was fed to growing male pigs (30-35 kg) in a replicated 4X4 Latin Square design with treatments basal (B) , B plus 40% unground pomace, B plus 40% ground pomace and B plus 40% barley. Grinding of pomace significantly improved the digestibility of all parameters measured, however, the barley-soybean meal basal ration was consistently better digested than either of the pomace treatments. The digestibility of whole and ground pomace was respectively: dry matter 10.7% and 20.8% (S.E.M. 1.30), fat 24.1% and 79.7% (S.E.M. 3.47), protein 10.6% and 14.7% (S.E.M. 4.83) and energy 7.9% and 28.4% (S.E.M. 1.80). Protein quality of ground (1mm) and freeze-dried pomace was evaluated with rats in metabolism cages to produce the following values: true protein digestibility 36.0% (S.E.M. 0.66), biological value 91.0% (S.E.M. 3.46), and net protein utilization 32.7% (S.E.M. 1.15). In rat growth trials, where pomace replaced barley incrementally, growth rate was not affected at replacement levels up to 40%, although feed efficiency declined consistently as the level of pomace in the diet increased. It is suggested that raspberry pomace could replace up to 20% of an energy feedstuff in a ration for growing swine without significantly reducing growth rate or feed efficiency. / Land and Food Systems, Faculty of / Graduate

The objectives o-f this research were to investigate the effects of blending Canbra or Canola oil with other oils or fats on the nutritive value and autoxidative stability of the blended oils, and to investigate the possibility of using hydrolyzed oils (free fatty acids) in the study of fatty acid balancing. Canbra oil (containing 6.1% erucic acid) was blended with sunflower oil or animal lard 1/1 (w/w). Canola oil (0.55% erucic acid) was blended with sunflower oil in the ratios 9/1, 8/2, 7/3, 6/4 and 5/5. The nutritional value was assayed using growing chicks fed lipid at 3% in a practical diet during a 4 week feeding period. Evaluation was made using body weight, weight gain, feed consumption, feed conversion, feed digestibility, lipid digestibility, total fatty acid digestibility, metabolizable energy and individual fatty acid digestibility. Results show that Canbra oil is equivalent to animal lard but significantly inferior to sunflower oil. Blending Canbra oil and sunflower oil or animal lard improved chick growth and fatty acid utilization over that demonstrated by the Canbra oil alone. Canola oil was equivalent to sunflower oil and soybean oil in supporting chick growth. The 7/3 and 5/5 blends showed synergistic improvement in promoting growth, fatty acid, protein and metabolizable energy utilization. It was concluded that Canola oil is nutritionally equivalent to either sunflower oil or soybean oil and that blending with sun-flower oil further improved its nutritional value. Oil blending rendered no significant detrimental effects on stability. The fatty acids of hydrolyzed Canola and sunflower oil showed nutritive performance equivalent to that of the intact oils. The fatty acids of a hydrolyzed 5/5 blend of Canola oil and sunflower oil showed reduced absorption of some fatty acids and the fatty acids of hydrolyzed soybean oil showed reduced diet and fatty acid absorption relative to the intact oils. These results demonstrate that feeding hydrolyzed oils may be a useful method of investigating fatty acid balance but more research is required in this area. / Land and Food Systems, Faculty of / Graduate

No description available.

No description available.

Three studies were conducted to evaluate a method for estimating grass and legume fractions in extrusa samples from esophageally-fistulated animals, based on different concentrations of neutral detergent fiber (NDF), Ca and lignin in grasses and legumes. In experiment 1, NDF, Ca and lignin concentrations were measured in mixtures of six combinations of red clover-orchardgrass and alfalfa-tall fescue (100:0; 80:20; 60:40; 40:60; 20:80; 0:100). The R² values were .90, .80 and .22 for Ca, NDF and lignin, respectively. In experiment 2, fresh tall fescue and red clover were collected during 8 d, mixed in the same proportions as in experiment 1, and each fraction was fed to esophageally-fistulated steers. Extrusa samples were collected without loss of saliva. Regression equations developed were y= 1.08 - .008x (R²= .91) for Ca and y= 50.9 + .22x (R²= .74) for NDF, where x represents % grass. In experiment 3, two esophageally-fistulated steers were allowed to graze in 20 4 X 4 m² plots of red clover and tall fescue after fasting overnight. The grass/legume proportions of the extrusas and the grab samples were extrapolated from slopes. The botanical composition of grab samples differed (P<.001) from that of extrusas for both components and for both animals. Extrapolation from NDF values tended to overestimate the proportion of grass in extrusa samples and underestimate it in grab samples. Calcium was not affected by salivation and mastication and was more reliable than NDF. Lignin was not an accurate predictor. / M.S.