Three experiments were conducted to determine the efficacy of an <i>Escherichia coli</i> 6-phytase (Quantum phytase) in laying hens fed corn-soybean meal based diets. In experiment 1, the Escherichia coli 6-phytase (Quantum) was evaluated for its efficacy in a 40-wk laying hen production trial. A total of 1080 White Leghorn hens were fed mash corn-soybean meal (CSM) based diets containing 0.35%, 0.25% or 0.15% of non-phytate phosphorus (NPP) with the 0.25% and 0.15% diets containing 200, 400 and 600 U/kg of exogenous phytase. Only minor differences in production characteristics were found between the 0.35% and 0.25% treatments regardless of phytase addition, indicating that 0.25% NPP resulted in P intake that was at or above the hens requirement. In contrast, the hens fed the 0.15% NPP diet without phytase supplementation had significantly reduced production performance in comparison to the 0.35% treatment. The addition of phytase to the 0.15% diet improved these production characteristics to levels equal to or better than the 0.35% diet. The results indicated that Quantum phytase was efficacious in CSM-based diets fed to White Leghorn laying hens and can be used to reduce the need for diet supplementation with inorganic phosphorus. In experiment 2, the effect of Quantum phytase on nutrient digestibility and bone ash in laying hens fed CSM-based diets was investigated. A total of 108 White Leghorn hens were fed CSM-based diets containing 0.35%, 0.25% or 0.15% NPP with the 0.25% and 0.15% diets containing 200, 400 or 600 U/kg of exogenous phytase. A linear reduction in phytate digestibility, ileal protein digestibility and soluble P was reported with increasing levels of exogenous phytase in the 0.25% diet. Tibial bone ash percentage was higher in 61-wk-old hens fed 0.25% diets supplemented with 200 or 400 U/kg phytase. Overall, the Quantum phytase was not efficacious in improving nutrient digestibility in laying hens fed CSM-based diets deficient in NPP. In experiment 3, the impact of dietary Ca and P level on the efficacy of an E. coli-derived 6-phytase and the apparent digestibility of various nutrients was investigated in White Leghorn laying hens fed CSM-based diets. A total of 384 White Leghorn hens were fed CSM-based diets containing four levels of Ca (2.5, 3.5, 4.5 or 5.5%), two levels of NPP (0.15 or 0.30%), and two levels of phytase (300 or 600 U/kg feed). Increasing dietary Ca caused a decrease in AMEn, duodenal protein digestibility, Ca and phytate digestibility, percentage soluble P in feces and the percentage of poor quality eggs, while significantly increasing bone ash and hen-housed and hen-day egg production. The higher level of NPP (0.30%) decreased AMEn, fecal protein, Ca and P digestibility, and hen-housed and hen-day egg production, while increasing fecal soluble P and egg specific gravity in comparison to the lower NPP level. The higher level of dietary phytase (600 U/kg feed) significantly increased AMEn, phytate and P digestibility, soluble P in feces, and hen-day and hen-housed egg production, while significantly reducing the percentage of soft shelled, cracked and broken eggs. Overall, dietary phytase, Ca and NPP levels, either as main effects or in an interactive manner, can affect apparent nutrient digestibility and production traits in laying hens fed CSM-based diets.

Three experiments were conducted to determine the efficacy of an <i>Escherichia coli</i> 6-phytase (Quantum phytase) in laying hens fed corn-soybean meal based diets. In experiment 1, the Escherichia coli 6-phytase (Quantum) was evaluated for its efficacy in a 40-wk laying hen production trial. A total of 1080 White Leghorn hens were fed mash corn-soybean meal (CSM) based diets containing 0.35%, 0.25% or 0.15% of non-phytate phosphorus (NPP) with the 0.25% and 0.15% diets containing 200, 400 and 600 U/kg of exogenous phytase. Only minor differences in production characteristics were found between the 0.35% and 0.25% treatments regardless of phytase addition, indicating that 0.25% NPP resulted in P intake that was at or above the hens requirement. In contrast, the hens fed the 0.15% NPP diet without phytase supplementation had significantly reduced production performance in comparison to the 0.35% treatment. The addition of phytase to the 0.15% diet improved these production characteristics to levels equal to or better than the 0.35% diet. The results indicated that Quantum phytase was efficacious in CSM-based diets fed to White Leghorn laying hens and can be used to reduce the need for diet supplementation with inorganic phosphorus. In experiment 2, the effect of Quantum phytase on nutrient digestibility and bone ash in laying hens fed CSM-based diets was investigated. A total of 108 White Leghorn hens were fed CSM-based diets containing 0.35%, 0.25% or 0.15% NPP with the 0.25% and 0.15% diets containing 200, 400 or 600 U/kg of exogenous phytase. A linear reduction in phytate digestibility, ileal protein digestibility and soluble P was reported with increasing levels of exogenous phytase in the 0.25% diet. Tibial bone ash percentage was higher in 61-wk-old hens fed 0.25% diets supplemented with 200 or 400 U/kg phytase. Overall, the Quantum phytase was not efficacious in improving nutrient digestibility in laying hens fed CSM-based diets deficient in NPP. In experiment 3, the impact of dietary Ca and P level on the efficacy of an E. coli-derived 6-phytase and the apparent digestibility of various nutrients was investigated in White Leghorn laying hens fed CSM-based diets. A total of 384 White Leghorn hens were fed CSM-based diets containing four levels of Ca (2.5, 3.5, 4.5 or 5.5%), two levels of NPP (0.15 or 0.30%), and two levels of phytase (300 or 600 U/kg feed). Increasing dietary Ca caused a decrease in AMEn, duodenal protein digestibility, Ca and phytate digestibility, percentage soluble P in feces and the percentage of poor quality eggs, while significantly increasing bone ash and hen-housed and hen-day egg production. The higher level of NPP (0.30%) decreased AMEn, fecal protein, Ca and P digestibility, and hen-housed and hen-day egg production, while increasing fecal soluble P and egg specific gravity in comparison to the lower NPP level. The higher level of dietary phytase (600 U/kg feed) significantly increased AMEn, phytate and P digestibility, soluble P in feces, and hen-day and hen-housed egg production, while significantly reducing the percentage of soft shelled, cracked and broken eggs. Overall, dietary phytase, Ca and NPP levels, either as main effects or in an interactive manner, can affect apparent nutrient digestibility and production traits in laying hens fed CSM-based diets.

Three experiments were conducted to determine the nutritive value of black Brassica napus (BBN), yellow Brassica juncea (YBJ) and yellow Brassica napus (YBN) in pig diets. In experiment 1, effect of multi-carbohydrase supplementation on SID of AA in BBN, YBJ and YBN was evaluated in growing pigs. The YBJ had similar SID of AA to BBN and enzyme did not affect SID of most of AA. The second and third experiments investigated the effect of high dietary inclusion of BBN and YBJ on weaned pig performance and nutrient digestibility with enzyme supplementation. The studies showed that weaned pigs can be fed diets containing up to 250 g/kg of either BBN or YBJ. Enzyme supplementation improved the nutrient digestibility. In conclusion, BBN and YBJ had similar digestible nutrient contents and there were no detrimental effects detected when pigs were fed up to 250 g/kg of BBN and YBJ in weaned pigs.

Three experiments were conducted to determine the nutritive value of black Brassica napus (BBN), yellow Brassica juncea (YBJ) and yellow Brassica napus (YBN) in pig diets. In experiment 1, effect of multi-carbohydrase supplementation on SID of AA in BBN, YBJ and YBN was evaluated in growing pigs. The YBJ had similar SID of AA to BBN and enzyme did not affect SID of most of AA. The second and third experiments investigated the effect of high dietary inclusion of BBN and YBJ on weaned pig performance and nutrient digestibility with enzyme supplementation. The studies showed that weaned pigs can be fed diets containing up to 250 g/kg of either BBN or YBJ. Enzyme supplementation improved the nutrient digestibility. In conclusion, BBN and YBJ had similar digestible nutrient contents and there were no detrimental effects detected when pigs were fed up to 250 g/kg of BBN and YBJ in weaned pigs.

The aim of this study was to determine growth responses and apparent total tract nutrient digestibility in growing pigs fed diets containing graded levels of distillers dried grains with solubles (DDGS) and to determine the effect of a multicarbohydrase enzyme (MC) supplementation on visceral organ mass and fasting whole-body oxygen consumption (FWBOC). In Experiment 1, 48 pigs (25.5 ± 0.14 kg BW) were assigned on the basis of sex and BW (2 pigs per pen) to 4 diets (6 pens per diet) based on corn-barley-soybean meal with 0, 10, 20 and 30% DDGS in a 42-d trial. Apparent total tract digestibilities (ATTD) of energy and other nutrients were determined using acid insoluble ash (AIA) as the indigestible marker. Inclusion of DDGS in the diets decreased (linear, P < 0.05) average daily gain (ADG) and tended to decrease gain to feed ratio (G:F) (linear, P = 0.067) but not average daily feed intake (ADFI) (P > 0.10); however, pigs fed the 20% DDGS diet had similar ADG as pigs fed the 0% DDGS diet. Increasing DDGS content in the diet linearly decreased (P < 0.01) the ATTD of DM, energy and CP (cubic, P < 0.05) but not (P > 0.10) P and Ca; however, ATTD of neutral detergent fiber (NDF) increased (linear, P < 0.01) when DDGS was included in the diet. In Experiment 2, 24 pigs (19.9 ± 0.46 kg BW) were randomly assigned to 3 corn-soybean meal-basal diets (8 pigs per diet): Control (C, 0% DDGS); basal diet with 30% DDGS (C+30% DDGS) or C+30% DDGS supplemented with MC (C+30% DDGS+MC). On d 15, WBOC during the 24- to 30-h postprandial period was determined using an open-circuit indirect calorimeter on 4 pigs per diet. On d 28, pigs were killed to determine visceral organ mass and intestinal morphology. There was no diet effect (P > 0.10) on final BW, FWBOC, and liver, spleen, pancreas, heart, stomach and caecum weights relative to empty BW. However, pigs fed the C and C+30% DDGS+MC had heavier (P = 0.05) empty BW compared with those fed unsupplemented 30% DDGS-containing diet. Small intestine, colon plus rectum and the portal-drained viscera (PDV) were heavier (P < 0.05) in DDGS-fed pigs compared with C; supplementing with MC substantially decreased the effect of DDGS on the weight of these visceral organs. Feeding pigs DDGS tended to decrease (P < 0.10) villous height (VH) and VH:CD in the ileum. Results show that including DDGS in grower pig diets up to 20% has no effect on performance although ATTD of energy, DM, and N may be reduced. Inclusion of DDGS at 30% increased PDV mass and reduced dressing percentage but these effects were overcome by a multicarbohydrase enzyme supplementation.

The aim of this study was to determine growth responses and apparent total tract nutrient digestibility in growing pigs fed diets containing graded levels of distillers dried grains with solubles (DDGS) and to determine the effect of a multicarbohydrase enzyme (MC) supplementation on visceral organ mass and fasting whole-body oxygen consumption (FWBOC). In Experiment 1, 48 pigs (25.5 ± 0.14 kg BW) were assigned on the basis of sex and BW (2 pigs per pen) to 4 diets (6 pens per diet) based on corn-barley-soybean meal with 0, 10, 20 and 30% DDGS in a 42-d trial. Apparent total tract digestibilities (ATTD) of energy and other nutrients were determined using acid insoluble ash (AIA) as the indigestible marker. Inclusion of DDGS in the diets decreased (linear, P < 0.05) average daily gain (ADG) and tended to decrease gain to feed ratio (G:F) (linear, P = 0.067) but not average daily feed intake (ADFI) (P > 0.10); however, pigs fed the 20% DDGS diet had similar ADG as pigs fed the 0% DDGS diet. Increasing DDGS content in the diet linearly decreased (P < 0.01) the ATTD of DM, energy and CP (cubic, P < 0.05) but not (P > 0.10) P and Ca; however, ATTD of neutral detergent fiber (NDF) increased (linear, P < 0.01) when DDGS was included in the diet. In Experiment 2, 24 pigs (19.9 ± 0.46 kg BW) were randomly assigned to 3 corn-soybean meal-basal diets (8 pigs per diet): Control (C, 0% DDGS); basal diet with 30% DDGS (C+30% DDGS) or C+30% DDGS supplemented with MC (C+30% DDGS+MC). On d 15, WBOC during the 24- to 30-h postprandial period was determined using an open-circuit indirect calorimeter on 4 pigs per diet. On d 28, pigs were killed to determine visceral organ mass and intestinal morphology. There was no diet effect (P > 0.10) on final BW, FWBOC, and liver, spleen, pancreas, heart, stomach and caecum weights relative to empty BW. However, pigs fed the C and C+30% DDGS+MC had heavier (P = 0.05) empty BW compared with those fed unsupplemented 30% DDGS-containing diet. Small intestine, colon plus rectum and the portal-drained viscera (PDV) were heavier (P < 0.05) in DDGS-fed pigs compared with C; supplementing with MC substantially decreased the effect of DDGS on the weight of these visceral organs. Feeding pigs DDGS tended to decrease (P < 0.10) villous height (VH) and VH:CD in the ileum. Results show that including DDGS in grower pig diets up to 20% has no effect on performance although ATTD of energy, DM, and N may be reduced. Inclusion of DDGS at 30% increased PDV mass and reduced dressing percentage but these effects were overcome by a multicarbohydrase enzyme supplementation.

Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was to investigate the nutrient digestibility of Angus calves born to cows that on average, shed early compared to calves from cows that shed later. Newly weaned, purebred Angus bull calves (early; n = 6, late; n = 6) were housed in metabolism crates for 10 d. Prior to the trial, calves had a 14 d adaption period to a 14% CP textured feed (CPC 14% Developer, CPC Commodities, Fountain Run, KY) and offered ad libitum Cynodon dactlyon hay and water. After 3 d crate acclimation period, urine, feces, orts, and hay samples were collected for 7 d. Concentrate was offered at 0.25% of average BW. Approximately 5% samples were taken of feces, and urine samples had 1-1.5% of 25% metaphosphoric acid added to prevent ammonia volatilization, and both collections were composited by animal. Orts were collected at 0600 h daily, dried, and composited by animal. Laboratory analysis included dry matter (DM), organic matter (OM), Ash, neutral detergent fiber (NDF), acid detergent fiber (ADF), Kjeldahl N (CP), and fat. Data were analyzed using the GLM procedure of SAS 9.4 in a completely randomized design with calf as the experimental unit. Significant (P ≤ 0.05) means were separated using Fischer’s protected LSD. The model for intake included average daily DM and OM (kg) and adjusted by body weight (BW%). For digestibility analysis, the model included: DM, OM, ash, NDF, ADF, hemi-cellulose (HC), CP, and fat. The N retention model included: N retained (g/d), N retained/consumed (%), and N retained/DM intake (%). There were no differences between early or late calves for DM intake (5.502 ± 0.2774 kg/d; 2.251 ± 0.1247 %BW), or OM intake (5.199 ± 0.2591 kg/d; 2.128 ± 0.1166 %BW). There were no differences in digestibility for either group for DM, OM, Ash, NDF, ADF, HC, CP, or fat (Table 1.). There were also no differences in N retention in either group of calves (3.686 ± 2.0242 g/d; 4.366 ± 2.3964 %; 0.064 ± 0.0355 %). Replication and further research are needed in this area to adequately understand factors influencing nutrient digestibility in calves born from early and late shedding dams.

A major challenge for the pig industry is to formulate starter diets that primarily fit the digestive capacity, maintain GIT health and promote growth without recourse to in-feed antimicrobials. Experiments were conducted to evaluate the efficacy of carbohydrase enzymes (CE) targeting non-starch polysaccharides (NSP) in enhancing gut health and function in piglets. First, an experiment was conducted to evaluate the effects of adding CE in piglet diets on growth performance, GIT bacterial activity and nutrient digestibility. Pigs fed diets containing CE had a higher ileal lactobacilli count, total organic acids concentrations, NSP digestibility and low ammonia compared with control. The effectiveness of CE targeting NSP was further evaluated using enterotoxigenic E. coli (ETEC) in a challenge model to evaluate the impact on gut health and function. Two approaches for the ETEC challenge were adopted; an in situ small intestine segments perfusion model and an in vivo model. Initially, a pilot study was conducted to establish and validate the in situ model. In the pilot study, conventional anti-diarrhea agents; fumaric acid, ZnO, egg yolk antibodies against ETEC K88 fimbriae and carbadox, attenuated fluid losses in ETEC-infected jejunal segments. Following the establishment of the in situ model, four experiments were conducted to study the effects NSP hydrolysis products (HP) from various feedstuffs (i.e. wheat, soybean meal, canola meal and flaxseed) on ETEC-induced secretory diarrhea. The results demonstrated that HP protected against ETEC-induced fluid and electrolyte losses. A further study was conducted to investigate the response of piglets fed diets containing HP and EYA singly or in combination upon oral challenge with ETEC. Feeding HP and EYA alone or in combination attenuated ETEC-enteritis symptoms such that piglets fed additives showed less pronounced acute phase responses and superior performance. Piglets fed diets containing additives had lower gastric pH, fewer ETEC adhered to ileal mucosa and lower incidence of diarrhea. Overall, reduction of intestinal pathogens or toxic bacterial metabolites contributes to enhanced GIT health and function. These novel results expand the scope of enzyme technology in animal nutrition within the new paradigm of dietary approaches to gut health and function.

A major challenge for the pig industry is to formulate starter diets that primarily fit the digestive capacity, maintain GIT health and promote growth without recourse to in-feed antimicrobials. Experiments were conducted to evaluate the efficacy of carbohydrase enzymes (CE) targeting non-starch polysaccharides (NSP) in enhancing gut health and function in piglets. First, an experiment was conducted to evaluate the effects of adding CE in piglet diets on growth performance, GIT bacterial activity and nutrient digestibility. Pigs fed diets containing CE had a higher ileal lactobacilli count, total organic acids concentrations, NSP digestibility and low ammonia compared with control. The effectiveness of CE targeting NSP was further evaluated using enterotoxigenic E. coli (ETEC) in a challenge model to evaluate the impact on gut health and function. Two approaches for the ETEC challenge were adopted; an in situ small intestine segments perfusion model and an in vivo model. Initially, a pilot study was conducted to establish and validate the in situ model. In the pilot study, conventional anti-diarrhea agents; fumaric acid, ZnO, egg yolk antibodies against ETEC K88 fimbriae and carbadox, attenuated fluid losses in ETEC-infected jejunal segments. Following the establishment of the in situ model, four experiments were conducted to study the effects NSP hydrolysis products (HP) from various feedstuffs (i.e. wheat, soybean meal, canola meal and flaxseed) on ETEC-induced secretory diarrhea. The results demonstrated that HP protected against ETEC-induced fluid and electrolyte losses. A further study was conducted to investigate the response of piglets fed diets containing HP and EYA singly or in combination upon oral challenge with ETEC. Feeding HP and EYA alone or in combination attenuated ETEC-enteritis symptoms such that piglets fed additives showed less pronounced acute phase responses and superior performance. Piglets fed diets containing additives had lower gastric pH, fewer ETEC adhered to ileal mucosa and lower incidence of diarrhea. Overall, reduction of intestinal pathogens or toxic bacterial metabolites contributes to enhanced GIT health and function. These novel results expand the scope of enzyme technology in animal nutrition within the new paradigm of dietary approaches to gut health and function.

Foram conduzidos dois experimentos no Departamento de Zootecnia da ESALQ/USP com o objetivo de estudar a substituição do milho moído fino pelos co-produtos farelo de glúten de milho e polpa cítrica peletizada em rações para bovinos terminados em confinamento. No Experimento 1 foram utilizados 88 machos cruzados (½ Braunvieh ¼ Angus ¼ Nelore) não castrados (407 kg), distribuídos em 24 baias por 57 dias. As rações continham 12% de bagaço de cana in natura e 88% de concentrado. Os tratamentos foram: (1) milho moído fino (M); (2) milho moído fino e farelo úmido de glúten de milho (MFUG); (3) polpa cítrica peletizada (P); (4) polpa cítrica peletizada e farelo úmido de glúten de milho (PFUG). O GPD e a EA dos animais não diferiram entre os tratamentos (P>0,05), porém houve efeito da fonte energética sobre a IMS, que foi maior para as rações com milho (P<0,05). Não foi observado efeito de fonte energética ou nível de farelo úmido de glúten de milho nos valores de ELm e ELg observados neste experimento (P>0,05), mas houve interação (P<0,05) com valores de energia mais altos para o tratamento PFUG em relação aos demais. No Experimento 2, foram utilizados 99 machos Nelore não castrados (348 kg), distribuídos em 20 baias por 85 dias. Os tratamentos foram: (1) milho moído fino (M); (2) milho moído fino e polpa cítrica peletizada (MPC); (3) milho moído fino e farelo úmido de glúten de milho (MFUG); (4) polpa cítrica peletizada e farelo úmido de glúten de milho (PFUG); (5) polpa cítrica peletizada e farelo seco de glúten de milho (PFSG). As rações continham de 5 a 11% de feno de gramínea como fonte de volumoso, formuladas para serem isoprotéicas. Não houve diferença (P>0,05) na IMS, GPD e EA para os tratamentos utilizados. A área de olho de lombo e espessura de gordura não foram afetadas pelos tratamentos, bem como as características qualitativas de carne (P>0,05). Acompanhando os resultados de desempenho, o valor energético das rações não diferiram entre si (P>0,05). Através dos resultados de ELm e ELg observados/esperados, concluiu-se que o milho brasileiro tem seu valor energético inferior ao milho descrito pelo NRC (1996). Os valores de energia do milho (ELm e ELg de 2,24 e 1,55 Mcal/kg) preditos através do amido fecal são semelhantes aos valores tabulados para o milho quebrado americano e superiores ao do milho moído. Com os resultados obtidos é possível afirmar que o farelo de glúten de milho e a polpa cítrica peletizada podem ser utilizados em substituição parcial ao milho moído fino e quando combinados, em substituição total ao milho moído fino em rações com altos teores de concentrado para bovinos em terminação, sem prejuízos ao desempenho e características de carcaça. / Two experiments were conducted at ESALQ/USPs Animal Science Department to evaluate corn gluten feed and dry citrus pulp in substitution for fine ground corn in high concentrate diets for finishing feedlot cattle. In Experiment 1, 88 croosbred (½ Braunvieh ¼ Angus ¼ Nelore) bulls (BW = 407 kg) were kept in 24 pens for 57 days. The rations contained 12% sugarcane bagass and 88% concentrate. The treatments were: (1) fine ground corn (M); (2) fine ground corn and wet corn gluten feed (MFUG); (3) citrus pulp pellets (P); (4) citrus pulp pellets and wet corn gluten feed (PFUG). ADG and G:F ratio did not differ among treatments (P>0,05), but there was an energetic source effect on DMI, higher for corn based diets (P<0,05). No differences were observed for energy souce or corn gluten feed level for NEm and NEg on this experiment (P>0,05), but an interaction (P<0,05) was observed for PFUG wich had higher energy value then the other treatments. In Experiment 2, 99 Nelore bulls (BW = 348 kg) were kept in 20 pens for 85 days. The treatments were: (1) fine ground corn (M); (2) fine ground corn and citrus pulp pellets (MPC); (3) fine ground corn and wet corn gluten feed (MFUG); (4) citrus pulp pellets and wet corn gluten feed (PFUG); (5) citrus pulp pellets and dry corn gluten feed (PFSG). The diets had 5 to 11% grass hay and 89 to 95% concentrate. No differences (P>0,05) were observed for DMI, ADG and G:F ratio among treatments. Diets energy value showed no differences among treatments (P>0,05). Observed/expected NEm and NEg values led to the conclusion that brazilian corn grain has lower energy value than what NRC (1996) tables show. Corn energy values (NEm and NEg was 2,24 and 1,55 Mcal/kg) predicted from fecal starch were similar to american cracked corn and higher than ground corn. Wet corn gluten feed and citrus pulp can be used in substitution for fine ground corn, alone or in combination, in high concentrate finishing feedlot diets, without depressing animal performance and carcass charateristics.