Response of broiler breeder pullets when fed hydrolyzed whole yeast from placement to 22 wk of age.

The study examined the effects of feeding broiler breeder pullets hydrolyzed whole yeast (HY) from hatch to 22 wk of age (WOA). A total of 524-day-old Ross 708 pullets were placed in floor pens (∼24 birds/pen) for the starter (0-4 WOA) and grower (5-18 WOA) phases, then transferred to the egg production facility and redistributed to ∼20 birds/pen for the prelay phase (19-22 WOA). Two diets were allocated to pens (0-18 WOA; n = 11) and (19-22 WOA; n-12). The diets were a control corn and soybean meal diet formulated to meet specifications and control plus 0.05% HY (HY). Birds had ad libitum access to feed in the first week and daily feed allocation based on pen BW from 2 WOA. Birds had free access to water throughout the trial. Body weight (BW) and uniformity (BW CV) were monitored. Boosters for infectious bronchitis and New Castle disease vaccines were administered at 18 WOA, and samples of pullets bled for antibody titer 5-day later. One pullet/pen was randomly selected, weighed, bled for plasma biochemistry, and necropsied for organ weights, ceca digesta for short-chain fatty acids (SCFA), and leg bones morphometry. In the starter and grower phases, birds fed HY were lighter and gained less (P < 0.05) than control birds. However, there were no diet effects (P > 0.05) on growth, the BW prelay phase, or BW uniformity throughout the trial. There were no (P > 0.05) diet effects on breast, gastrointestinal, liver and bursa weights, serum antibody titers, plasma biochemistry, SCFA and bone attributes. However, pullets fed HY had heavier (P = 0.047) spleen and tended to have lower (P = 0.080) plasma concentrations of aspartate aminotransferase (AST) relative to control pullets. In conclusion, the parameters assessed showed no negative consequences of feeding HY to broiler breeder pullets. However, effects on the spleen and plasma AST may indicate modest modulation of immunity and metabolism. The impact of the provision of HY during broiler breeder pullet phase on reproductive performance and chick quality should be investigated.

Egg production, egg quality, and fatty acids profiles in eggs and tissues in Lohmann LSL lite hens fed algal oils rich in docosahexaenoic acid (DHA).

Enriching eggs with omega-3 fatty acids (n-3 FA), such as docosahexaenoic acid (DHA), is a well-accepted practice that benefits the egg industry and consumers. However, issues around cost, sustainability, and product acceptance have necessitated the search for alternatives to feeding hens fish oil for DHA enrichment. The effects of feeding 2 algal oils on egg production and DHA enrichment in eggs and selected tissues were investigated. The algal oils were: 1) OmegaPro (OPAO) standardized algal oil for DHA content and 2) Crude algal oil (CAO). A total of 400, 46-wk-old Lohmann LSL lite hens were housed in enriched cages (10 birds/cage) and allocated 5 diets (n = 8) for a 12-wk trial. The iso-caloric and -nitrogenous diets were a standard corn and soybean meal diet, standard plus 0.25 or 0.76% OPAO and standard plus 0.23 or 0.69% CAO; algal oils diets supplied similar DHA at each level. Egg production indices (hen day egg production, feed intake, FCR, egg weight, egg mass, and eggshell quality) were monitored for 10 wk. Diet samples were analyzed for fatty acids (FA) on wk 1, 6, and 12 and eggs on wk 4, 5, 6, 9, and 12. At the end of the trial, one hen/cage was weighed and dissected for liver, breast and thigh for FA and long bones for ash content analyses. Concentration of omega-6 to omega-3 FA ratio was 12.9, 6.64, 3.48, 6.96, and 3.59 for standard, 0.23 and 0.76% OPAO, 0.25 and 0.69% CAO, respectively. Algal oils increased (P ≤ 0.046) eggshell thickness linearly. The concentration of DHA in the eggs from the birds fed the standard, 0.23 and 0.76% OPAO, 0.25 and 0.69% CAO was 84, 195, 286, 183, and 297 mg/100g egg, respectively, and algal oils enriched eggs with DHA linearly and quadratically (P ≤ 0.01). In conclusion, algal oils increased the concentration of DHA in eggs and had no adverse effects on egg production and eggshell quality.

Egg production, egg quality, organ weight, bone ash, and plasma metabolites in 30-week-old Lohmann LSL lite hens fed corn and soybean meal-based diets supplemented with enzymatically treated yeast.

Highly prolific modern hens are susceptible to metabolic disorders that could be modulated by functional feedstuffs such as enzymatically treated yeast (ETY). Therefore, we assessed the dose-response of ETY on hen-day egg production (HDEP), egg quality attributes, organ weight, bone ash, and plasma metabolites in laying hens. A total of 160 thirty-week-old Lohmann LSL lite hens were placed in 40 enriched cages (4 birds/cage) based on body weight (BW) and allocated to 5 diets in a completely randomized design for a 12-wk trial. The diets were isocaloric and isonitrogenous corn and soybean meal based supplemented with 0.0, 0.025, 0.05, 0.1, or 0.2% ETY. Feed and water were provided ad libitum; HDEP and feed intake (FI) were monitored weekly, whereas egg components, eggshell breaking strength (ESBS), and thickness (EST) were monitored biweekly, and albumen IgA concentration was measured on wk 12. At the end of the trial, 2 birds/cage were bled for plasma and necropsied for liver, spleen, and bursa weight, ceca digesta for short chain fatty acids (SCFA) and tibia and femur for ash content. Supplemental ETY reduced HDEP quadratically (P = 0.03); the HDEP was 98, 98, 96, 95, and 94% for 0.0, 0.025, 0.05, 0.1, and 0.2% ETY, respectively. However, ETY linearly and quadratically (P = 0.01) increased egg weight (EW) and egg mass (EM). Specifically, EM was 57.9, 60.9, 59.9, 58.9, and 59.2 g/b for 0.0, 0.025, 0.05, 0.1, and 0.2% ETY, respectively. Egg albumen increased linearly (P = 0.01), and egg yolk decreased linearly (P = 0.03) in response to ETY. In response to ETY, the ESBS and plasma Ca increased linearly and quadratically (P ≤ 0.03). Plasma concentration of total protein and albumin increased quadratically (P ≤ 0.05) with ETY. Diets had no (P > 0.05) effects on FI, FCR, bone ash, SCFA, and IgA. In conclusion, 0.1% or higher ETY reduced egg production rate; however, linear improvement in EW and shell quality linked to larger albumen and higher plasma protein and Ca suggested modulation in protein and calcium metabolism.

Enzymatically treated yeast bolstered growth performance of broiler chicks from young broiler breeders linked to improved indices of intestinal function, integrity, and immunity.

Older breeder chicks (OBC) are heavier and robust at hatch than younger breeder chicks (YBC). However, the implications of broiler breeder age on chick intestinal function and the role of functional feedstuffs are unexplored. We evaluated the effects of broiler breeder age and the impact of feeding YBC enzymatically treated yeast on growth, nutrient utilization, and indices of intestinal function. Fertile Ross 708 eggs: 2,250 (56.5 ± 3.4g) from 30-wk-old (YBC) and 550 (64.2 ± 4.2 g) from 47-wk-old (OBC) were hatched and placed in 48 pens (44 chicks/pen) containing equal males and females for growth and intestinal function evaluation and 36 cages (5 chicks/cage) for metabolizable energy (AME). Five corn and soybean meal-based diets were formulated to contain 0, 0.05, 0.10, 0.20, and 0.40% HY40 for a 3-phase feeding program (starter: days 0-10, grower: days 11-24, and finisher; days 25-42). Grower phase diets also contained a 0.3% TiO2 indigestible marker. The diets were allocated within YBC in a completely randomized block design (n = 8 for pens; n = 6 for cages). The OBC were fed a 0% yeast diet. Feed and water were provided freely; BW and feed intake were monitored, and excreta samples were collected on days 17 to 21 for apparent retention (AR). Birds were necropsied for plasma, jejunal tissues, organs weight, and ceca digesta. The OBC were heavier (P < 0.01) than YBC at hatch. Final BW of OBC and YBC fed, ≥0.10% yeast, was similar (P > 0.05). The OBC had similar FCR (P > 0.05) to YBC fed 0 to 0.10% yeast but higher (P = 0.003) than for YBC fed ≥0.20% yeast. Jejunal villi height to crypt depth ratio (VCR) and IgA were higher in OBC than 0% yeast (P = 0.01). Yeast increased VCR, bursa weight, jejunal, and plasma IgA (P = 0.01). The YBC fed ≥0.10% yeast had higher (P < 0.05) AR of crude protein, and gross energy than OBC and YBC fed 0 or 0.05% yeast. In conclusion, yeast improved YBC performance to the level of OBC linked to improved intestinal function, integrity, and immunity.