ABSTRACT This study evaluated the productive performance and carcass characteristics of broiler chickens fed diets containing prilled fats of palm oil (PFPO) or calcium soaps of palm oil (CaSPO) replacing vegetable oils (VO). A total of two hundred 1-day-old male Ross 308 chickens were allocated in a 2 × 2 randomized factorial design. Diets included 2 PFPO levels (0 and 50%) and 2 CaSPO levels (0 and 50%). The level was the percentage of substitution of VO by granulated fats. The study had two phases (starter and finisher), each lasting 21 days. In the starter phase, PFPO did not influence (main effects; p>0.05) feed intake and body weight gain, but improved (main effect; p=0.03) feed conversion. In the finisher phase and the total study, PFPO had no effect (p>0.05) on these productive variables. Throughout the study, CaSPO did not influence feed intake (main effect; p>0.50), but decreased weight gain and had a negative effect on feed conversion (main effects; p<0.05). There was no influence of fats (PFPO or CaSPO) on carcass yield, breast, drumsticks plus thighs, and wings (main effects; p>0.05). Chickens fed CaSPO had lower (main effect; p=0.02) carcass weight. The only PFPO × CaSPO interaction (p=0.04) was for back yield. Results showed that PFPO or CaSPO could be employed in formulating broiler chicken diets, as they are less expensive than conventional VO. Partial substitution of VO for PFPO had minimal effect on productive variables, although partial dietary inclusion of CaSPO might slightly reduce the production of broiler chickens.

ABSTRACT Vegetable oils (VO) and animal fats are conventional lipid sources used in feed formulations. Frying fats (FF) and calcium soaps of palm oil (CaSPO) are low-cost lipid sources. This study evaluated the productive performance of broiler chickens fed diets with CaSPO in substitution for VO or FF. Two hundred, 1-day old male broiler chickens were allocated in a randomized design with factorial arrangement (22). Diets included 2 lipid sources (FF and VO) and 2 CaSPO levels (0 and 50%). The study had two phases (starter and finisher) of 21 days each. For the starter phase there was no effect (p>0.05) of dietary treatments on the chickens’ productive performance. For the finisher phase birds fed diets with FF had higher feed intake and feed conversion ratio (main effect; p<0.01) than those fed diets with VO. Over the 42-day feeding period animals fed FF had higher feed conversion ratio (main effect; p=0.02) and tended (p=0.08) to show higher feed intake than those fed diets with VO. The CaSPO substitution for VO or FF had no effect (p>0.05) on the productive performance of broiler chickens. There was no influence of treatment on carcass yield. The drumsticks plus thighs were higher (main effect; p<0.01) in birds receiving VO than in those receiving FF. The interaction (fat source*CaSPO) was not significant (p>0.05). These results may indicate that VO is superior to FF and CaSPO may substitute for VO or FF without affecting productive performance of broiler chickens. Lipid source showed small influence on carcass characteristics.

ABSTRACT To study the antimicrobial and uric acid-preserving activity of pine bark tannin on poultry litter composting, antibiotic-free wood chip-based poultry litter was distributed (11 g) to 50-mL conical centrifuge tubes and immediately amended with 1.3 mL0.4 M sodium phosphate buffer (control) or with 1.3 mL condensed tannins from pine bark (Pinus palustris; 9 % tannin wt/vol in water). All tubes (n = 3 tubes/treatment) were inoculated with a novobiocin and naladixic acid-resistant Salmo-nella typhimurium (STNN) to achieve 3.0 log10 CFU/g and incubated at 37oC for 3 days to simulate an initial compost period. Wildtype E. coli and the challenge STNN strain as well as concentrations of ammonia, uric acid and urea were measured on days 0 and 3. Pine bark tannin treatment decreased (p<0.01) STNN populations in the litter by 0.6 log units compared to the controls. Wildtype E. coli populations were unaffected by tannin treatment (p>0.05). Ammonia accumulation decreased (p<0.01) 23% in tannin-treated litter compared to the control (2.8 ± 0.1 µmol/g). Conversely, the residual uric acid concentration was 1.6-fold higher (p=0.02) in litter treated with the pine bark tannin than in the control litter. Urea concentrations were unaffected by tannin treatment (p>0.05). Results suggest that pine bark tannin treatment may preserve uric acid and reduce ammonia volatilization in composted litter while aiding Salmonella control.

Abstract Solid-state fermentation can be used to produce feeds for ruminants, which can provide an enriched population of yeasts to improve ruminal fermentation. Fermentation of apple bagasse was performed to obtain a yeast-rich product, with the objective of isolating, identifying, and characterizing yeast strains and testing their capability to enhance in vitro ruminal fermentation of fibrous feeds. Yeasts were isolated from apple bagasse fermented under in vitro conditions, using rumen liquor obtained from cannulated cows and alfalfa as a fibrous substrate. A total of 16 new yeast strains were isolated and identified by biochemical and molecular methods. The strains were designated Levazot, followed by the isolate number. Their fermentative capacity was assessed using an in vitro gas production method. Strain Levazot 15 (Candida norvegensis) showed the greatest increase in gas production (p < 0.05) compared with the yeast-free control and positively affected in vitro ruminal fermentation parameters of alfalfa and oat straw. Based on these results, it was concluded that the Levazot 15 yeast strain could be potentially used as an additive for ruminants consuming high-fiber diets. However, further studies of effects of these additives on rumen digestion, metabolism, and productive performance of ruminants are required.