Complete replacement of soybean meal with black soldier fly larvae meal in feeding program for broiler chickens from placement through to 49 days of age reduced growth performance and altered organs morphology.

Black soldier fly larvae meal (BSFLM) is characterized with good nutritional and functional attributes. However, there is limited data on inclusion of BSFLM in broiler chicken rations from placement through to market weight. Therefore, we examined growth and organ responses of partial to complete replacement of soybean meal (SBM) with BSFLM in a practical feeding program. A total of 1,152 d-old male Ross × Ross 708 chicks were allocated to 48 pens and assigned one of six diets (n = 8). The diets were: a basal corn-SBM diet (0%BSFLM), 4 diets in which SBM in 0%BSFLM was replaced with BSFLM at 12.5, 25, 50, and 100% and a final diet (0 + AGP) in which 0%BSFLM was treated with coccidiostat (70 mg Narasin/kg) and antibiotic (55 mg Bacitracin Methylene Disalicylate/kg). For energy fortification, soy oil was used for 0%BSFLM diets and black soldier fly oil in the other diets. Body weight, feed intake (FI), BW gain (BWG), and mortality-corrected feed conversion ratio (FCR) were reported. Organ weights were recorded on d 24 and 49. On d 10, birds fed diets 12.5, 25, and 0 + AGP had higher BWG than birds fed diets 0, 50, and 100 (P < 0.01), and birds fed diet 100 had lower BWG than birds fed diets 0 or 50 (P < 0.01). Birds fed diets 50 and 100 had lower BWG than birds fed all other diets on d 24 and 49 (P < 0.05). Overall (d 0-49), BSFLM linearly (P < 0.01) decreased BW, BWG, and FI and increased FCR and mortality. The overall BWG of 50 and 100% BSFLM birds was 92 and 81% of birds fed 0%BSFLM, repectively and coresponding overall FI was 96 and 90%. An increase in gizzard, small intestine, pancreas, and liver relative weights were observed with increasing BSFLM inclusion (P < 0.01). The data indicated that lower levels of BSFLM could provide some growth-promoting effects commensurate to antibiotics in the starter phase. However, replacing SBM with greater amounts (≥50) of BSFLM reduced growth and increased organ size.

Effects of early feeding of enzymatically treated yeast on growth performance, organ weights, intestinal histomorphology, and ceca microbial metabolites in broiler chickens subjected to Eimeria challenge.

The study evaluated effects of early feeding of enzymatically treated yeast on growth performance and selected physiological responses in broiler chickens. A total of 480-day-old (male) Ross × Ross 708 broiler chicks were placed in 24 floor pens (20 birds per pen) and allocated to 2 diets (control vs. yeast) in a completely randomized block design (n = 12). Diets were formulated for a 5-phase feeding program: Pre-starter; d 0 to 6 Starter; d 7 to 15, Grower: d 16 to 28, Finisher 1; d 28 to 42 and Finisher 2; d 43 to 56. The yeast was applied in pre-starter and starter diets at 0.6 and 0.2%, respectively. Birds received a common diet from d 16 to 56. Feed intake (FI) and body weight (BW) were recorded by phase for calculation of BW gain (BWG) and FCR. On d 10, all birds received an oral dose of 25,000 E. acervullina and 5,000 E. maxima sporulated oocysts in 1 mL of sterile saline. On d 15 post-hatch, one bird per pen was sacrificed for organ weights (gizzard, small intestine, ceca, liver, spleen, liver, and bursa), jejunal tissues for histomorphology and ceca digesta for microbial activity. On d 56, one bird per pen was sacrificed for organs and breast weight. In pre-starter phase, yeast fed birds showed improved (P < 0.05) BWG and FCR than control fed birds. Combining pre-starter and starter phases, the FCR of yeast fed birds showed improved FCR (1.115 vs. 1.135; P < 0.05) than control. The overall BWG (d 0-56) was 3.920 and 3.962 kg/ bird and corresponding values for FCR were, 1.808 and 1.755, for the control and yeast, respectively. Diets had no (P > 0.05) effects on physiological responses evaluated on necropsied birds except that yeast birds had (P < 0.05) lighter bursa than control birds on d 15. The current data indicated that yeast could support growth in early life of broiler chickens, but these effects were not sustained after the transitioning birds to common grower and finisher diets.

Growth performance, immune status, gastrointestinal tract ecology, and function in nursery pigs fed enzymatically treated yeast without or with pharmacological levels of zinc.

Growth performance and physiological responses of nursery piglets when fed enzymatically treated yeast (HY40) and pharmacological ZnO alone or in combination were investigated. A total of 144 pigs (21 d old, BW 7.32 ± 0.55 kg) were placed in 36 pens (4 pigs/pen). Pigs were randomly assigned to one of four dietary treatments (n = 9): 1) control corn-wheat-soybean meal diet (control), 2) control + HY40 (HY40), 3) control + (ZnO) and 4) control + HY40 + ZnO (HY40+ZnO). Inclusion of HY40 and ZnO was 0.5% and 3,000 ppm in phase I (days 0 to 14), respectively, and halved in phase II (days 15 to 42). All diets contained 0.2% TiO2 for determination of apparent total tract digestibility (ATTD) of components. Body weight and feed disappearance were recorded weekly. One pig per pen was killed for organ weights, blood, and tissue samples on day 14. Except for phase II, when HY40 + ZnO pigs had greater average daily feed intake (P = 0.004) than all other treatments, there were no (P > 0.05) interactions between HY40 and ZnO on growth performance. Pigs fed HY40 or ZnO containing diets were heavier (P < 0.05) than pigs fed without by the end of the study. On day 14, pigs fed additives exhibited higher (P ≤ 0.009) ATTD of dry matter (DM) and gross energy (GE) than control pigs. On day 28, pigs fed control, HY40, and HY40 + ZnO had greater (P ≤ 0.022) ATTD of DM, crude protein, and GE than piglets fed ZnO only. Pigs fed HY40 + ZnO had lower ileal digesta Escherichia coli concentration (P < 0.05) than HY40 and control pigs. Ileal digesta of pigs fed ZnO diets had higher lactobacillus to E. coli ratio (1.44 vs. 1.20; P = 0.001), exhibited higher concentrations of acetic (P = 0.01) and butyric acid (P = 0.01) but lower lactic (P = 0.02) and total short chain fatty acids (P = 0.033) than pigs fed non-ZnO diets. Greater (P < 0.05) mRNA expression of nutrient transporters, tight junction proteins, and fecal excretion of zinc (Zn) was observed in ZnO pigs relative to non-ZnO pigs. Pigs fed HY40 diets had greater (P = 0.002) villus height to crypt depth ratio (VH:CD) than non-HY40 pigs. The concentration of plasma IgA was higher (P = 0.04) in HY40 + ZnO pigs relative to other pigs, whereas HY40 pigs showed higher (P < 0.001) jejunal IgA than non-HY40 pigs. Although the mode of action of HY40 and ZnO differed, the present study indicated that HY40 improved growth performance and jejunal function and immunity, making HY40 an effective alternative to pharmacological ZnO in nursery pigs feeding programs.

Abrupt weaning of pig results in nutritional, environmental, and psychological stresses leading to reduced feed intake, little or no weight gain and in some instances diarrhea, morbidity, and mortality. The post-weaning growth performance lag is often managed by use of antimicrobial growth promoters (AGP), pharmacological levels of trace elements such as zinc oxide (ZnO), specialty feed ingredients, and additives. However, many jurisdictions have already banned, and others are considering banning/restricting use of AGP to abate burgeoning levels of antimicrobial resistance in pathogens of animal and human. The European Union confirmed banning pharmacological ZnO effective June 2022 because of environmental pollution. In this context, identifying alternative nutritional strategies for managing newly weaned pigs is of global concern. Yeast derivatives have been proposed to be beneficial in transitioning piglets. However, there is little available information on comparative efficacy of yeast derivatives and pharmacological ZnO. The current study demonstrated that enzymatically treated yeast (HY40) had positive effects on growth, intestinal histomorphology, nutrient digestibility, and immune indices in nursery pigs. Through differing modes of action, overall growth performance of HY40 piglets was comparable to that of pharmacological ZnO piglets.

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.

Amino acids and energy digestibility in extruded or roasted full fat soybean fed to broiler chickens without or with multienzyme supplement containing protease, phytase, and fiber degrading enzymes.

Effects of processing and multienzyme supplement (MES) on standardized ileal digestibility (SID) of amino acids, apparent retention (AR) of components and metabolizable energy (AME) content in full fat soybean seeds (FFSB) were investigated in broiler chickens. The FFSB were either extruded (EFFSB) or roasted (RFFSB). A nitrogen free diet (NFD) was formulated for SID of AA calculation. The FFSB diets contained 20% crude protein with the ratio of corn starch: sucrose: soy oil (sole sources of energy in NFD) kept constant for calculation of AME. The FFSB diets were fed without or with MES containing phytase, protease, and fiber degrading enzymes. All diets had TiO2 indigestible marker. A total of 400-dayu-old Ross 708 male chicks were fed a commercial diet to d 13. On d 14, birds were weighed individually and allocated to cages (10 birds/cage, n = 8). Birds had free access to feed and water. Excreta samples were collected on d 18 to 20, and all birds were necropsied on d 21 for terminal ileal digesta samples. There was no (P > 0.05) interaction between processing and MES on SID of AA. Birds fed EFFSB had higher (P ≤ 0.048) SID of Arg, Ile, Lys, and Met than birds fed RFFSB. Birds fed MES had higher (85.5 vs. 80.8%; P = 0.050) SID of Lys than birds fed non-MES diet. There was interaction (P ≤ 0.036) between processing and MES on AR of Ca and P; MES improved retention but largely in EFFSB. There was an interaction (P = 0.016) between processing and MES on energy utilization such that MES improved AR of GE, AME, and AMEn in RFFSB only. In general, birds fed EFFSB exhibited higher (P < 0.01) energy utilization than birds fed RFFSB. In conclusion, lower Lys and energy utilization in RFFSB relative to EFFSB reflected the impact of the processing regimen. Supplemental enzyme improvement on Lys and minerals digestibility in FFSB and energy utilization in RFFSB suggested value in heat processed feedstuffs.

Effect of dietary supplementation of ß-mannanase on growth performance, carcass characteristics, excreta microflora, blood constituents, and nutrient ileal digestibility in broiler chickens.

OBJECTIVE: The aim of the present study was to investigate the effects of dietary supplementation of ß-mannanase on growth performance, carcass characteristics, excreta microflora, blood constituents, and nutrient digestibility in broiler chickens. METHODS: A total of 680 one-d-old Ross 308 (as hatched) broiler chickens were used in a 35-d growth assay. Chicks were sorted into pens with 17 birds/pen and 10 pens/treatment. Treatment diets were contained either 44% or 48% crude protein (CP) soybean meal (SBM) with or without ß-mannanase. RESULTS: Using SBM containing 48% CP led to an improvement (p<0.05) in feed conversion ratio (FCR) from d 1 to 14. Addition of ß-mannanase to the diets significantly improved body weight gain (BWG) and FCR from d 1 to 14. During overall experimental period, BWG was affected (p<0.05) by CP level of SBM and inclusion of ß-mannanase, but FCR and feed intake were not affected. Carcass characteristics were not influenced by treatment diets. The results showed that digestibility of dry matter (DM), nitrogen (N), and energy was not affected by CP level of SBM and/or inclusion of ß-mannanase. Among essential amino acids (EAA) apparent digestibility of valine, methionine, and leucine improved (p<0.05) by the addition of ß-mannanase to the diets. The results demonstrated that ileal digestibility of DM, N, and energy was not affected by treatment diets. Among EAA, the ileal digestibility of valine and arginine was higher (p<0.05) in the diets containing 48% CP SBM and/or ß-mannanase. Excreta Lactobacillus count increased (p<0.05) by the addition of ß-mannanase to the diets. Blood urea nitrogen, creatinine, and total protein level were not affected by treatments. CONCLUSION: Feeding chickens with diets containing 44% CP SBM resulted in detrimental effects on growth performance and digestibility of nutrients, but addition of ß-mannanase to the 44% CP diet improved the growth performance of chickens without any effects on carcass characteristics.

Growth performance, organ attributes, nutrient and caloric utilization in broiler chickens differing in growth rates when fed a corn-soybean meal diet with multienzyme supplement containing phytase, protease and fiber degrading enzymes.

Growth performance, organ weight, ceca digesta short chain fatty acids (SCFA), jejunal histomorphometry, tibia ash, apparent retention (AR) of components and caloric efficiency were investigated in broiler chicken strains differing in growth rate fed diets with multienzyme supplement (MES). The strains differed in estimated time to reach 2.1 kg BW: 37, 43, 47, and 50 d and were designated C, F, J, and N, respectively. A corn-soybean meal diet was formulated for 2-phase program (starter and grower) and fed without or with MES containing phytase, protease and fiber-degrading enzymes. A total of 640-day-old chicks (42.3 + 0.01 g/bird) were housed in cages (5 cockerels and 5 pullets/cage) and allocated to give 8 replicates/ strain and diet combination. Equal amount of feed was fed based on observed ad-libitum intake of C strain in the starter (d 0-14) and grower (d 15-28). Body weight was monitored, grab excreta samples taken and at completion of allocated feed one bird per cage necropsied for samples. With exception of P, apparent metabolizable energy corrected for nitrogen (AMEn) and ceca digesta acetic acid, there was no (P > 0.05) interaction between strain and MES on examined responses. Strains differed (P < 0.01) on growth, FCR, gizzard weight, tibia ash, breast weight, ceca digesta concentration of lactic, propionic, and isobutyric acid and caloric efficiency. The final body weight (BW) was 1,344, 1,134, 959, and 916 g/bird for C, F, J, and N, respectively. Corresponding caloric efficiency was 4,930, 5,807, 6,680 and 7,199 kcal/kg BW gain, respectively. Birds fed MES had higher BW gain (P < 0.05) in grower phase, larger gizzard, higher AR of CP, crude fat, neutral detergent fiber, and Ca than non-MES birds. In conclusion, growth rate influenced organ attributes, nutrient, and caloric utilization. Enzyme supplementation improved growth in grower phase and nutrient utilization independent of strain, suggesting that effects of feed enzymes are not influenced by inherent growth rate.

In pursuit of a better broiler: growth, efficiency, and mortality of 16 strains of broiler chickens.

To meet the growing consumer demand for chicken meat, the poultry industry has selected broiler chickens for increasing efficiency and breast yield. While this high productivity means affordable and consistent product, it has come at a cost to broiler welfare. There has been increasing advocacy and consumer pressure on primary breeders, producers, processors, and retailers to improve the welfare of the billions of chickens processed annually. Several small-scale studies have reported better welfare outcomes for slower-growing strains compared to fast-growing, conventional strains. However, these studies often housed birds with range access or used strains with vastly different growth rates. Additionally, there may be traits other than growth, such as body conformation, that influence welfare. As the global poultry industries consider the implications of using slower growing strains, there was a need for a comprehensive, multidisciplinary examination of broiler chickens with a wide range of genotypes differing in growth rate and other phenotypic traits. To meet this need, our team designed a study to benchmark data on conventional and slower-growing strains of broiler chickens reared in standardized laboratory conditions. Over a 2-year period, we studied 7,528 broilers from 16 different genetic strains. In this paper, we compare the growth, efficiency, and mortality of broilers to one of two target weights (TW): 2.1 kg (TW1) and 3.2 kg (TW2). We categorized strains by their growth rate to TW2 as conventional (CONV), fastest-slow strains (FAST), moderate-slow strains (MOD), and slowest-slow strains (SLOW). When incubated, hatched, housed, managed, and fed the same, the categories of strains differed in body weights, growth rates, feed intake, and feed efficiency. At 48 d of age, strains in the CONV category were 835 to 1,264 g heavier than strains in the other categories. By TW2, differences in body weights and feed intake resulted in a 22 to 43-point difference in feed conversion ratios. Categories of strains did not differ in their overall mortality rates.

Research Note: Comparative gastrointestinal, tibia, and plasma attributes in 48-day-old fast- and slow-growing broiler chicken strains.

Emerging market differentiation for broiler meat from strains exhibiting a range of growth rates is necessitating comparative research on various physiological and production aspects of these strains. The objective of the present study was to compare select gastrointestinal, tibial, and plasma attributes in a sample of 48-day-old (50 male and 50 female) broilers obtained from fast-and slow-growing flocks maintained under similar feed and management regimens. Eight birds were randomly selected from a fast (B; representative of modern commercial strains) and each of the 4 slow-growing strains (SG; D, H, M, and E). The strains differed by estimated time to reach 2.2 kg bodyweight corresponding to 36, 50, 42, 44, and 50 D for B, D, H, M, and E, respectively. Blood samples were collected to determine plasma metabolites, and birds were subsequently euthanized, weighed, and necropsied for gizzard and small intestine weight, jejunal tissue for histomorphology, ceca digesta samples for concentration of short-chain fatty acids (SCFA) and left tibia for ash content. Gizzard was heavier (P < 0.01) for D, H, and M than that for B and E, whereas the small intestine was lighter (P < 0.01) for B, D, and H than for M and E. There were no (P > 0.05) strain differences on SCFA, jejunal villus height and crypt depth, plasma proteins, and electrolytes. Strains D, H, and M exhibited higher (P = 0.01) tibia ash concentration than B; E was intermediate and not different (P > 0.05) from any strain. Specifically, the tibia ash for B, D, H, SG 3, and E were 1.24, 1.44, 1.43, 1.49, and 1.39 g/kg BW, respectively. The B birds showed higher (P < 0.01) plasma concentrations of aspartate transaminase, creatine kinase, lactate dehydrogenase, and creatinine than SG strains. In conclusion, although B and some SG strains had lighter gastrointestinal tract indicative of energy efficiency, higher circulating plasma enzymes in B birds suggested impaired hepatic function. Moreover, lower tibia ash in B suggested disproportionate body mass relative to skeletal support.