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1. A total of 864 d old (male) Ross × Ross 708 broiler chicks were allocated to 48 floor pens (12 pens/treatment and 18 birds/pen) to investigate dose-response of a blend of seaweeds (SB) on growth performance, breast yield, jejunal histomorphology, microbial metabolites and community and plasma biochemical profile. 2. A maize-soybean meal diet was formulated with 0, 5, 10 or 20 g/kg of SB. Diets were formulated for a three-phase feeding programme (starter: d 0-10, grower: d 11-24, and finisher: d 25-42) and met or exceeded Aviagen nutrient specifications. Diets were allocated to pens (n = 12) balanced for body weight (BW). Birds had free access to feed and water, BW and feed intake (FI) were monitored by phase. One bird per pen was randomly selected on d 42, bled for plasma, and samples for intestinal tissue and caecal digesta were taken. Microbial DNA was extracted and submitted for microbial community profile using the Illumina Miseq® platform. 3. In the starter phase, SB linearly (

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.

There is limited information on the effects of enteric pathogen on bone quality in rapidly growing broiler chicks. We examined tibia and femur attributes (length, diameter, relative weight of ash content [AC] to the BW, ash concentration [AP]) and serum bone-turnover markers including receptor activator of nuclear factor kappa-B ligand (RANKL) for resorption, alkaline phosphatase (ALP) for mineralization, and selected serum metabolites in 14-day-old broilers challenged with Eimeria. A total of 160 (80 males and 80 females) 1-day-old Ross × Ross 708 chicks were used. Based on BW, birds were placed within sex in cages (5 birds per cage) and fed chick starter diets to day 9 of age. On day 9, half of the cages were orally gavaged with 1 mL of Eimeria culture (100,000 oocysts of E. acervulina and 25,000 oocysts of E. maxima) and the other half (unchallenged control) received 1 mL 0.9% saline in distilled water. On day 14, 2 birds were randomly selected and necropsied for intestinal lesion score, blood, tibia, and femur samples. Data were analyzed in a 2 (challenged vs. unchallenged) × 2 (males vs. females) factorial arrangement. There was no interaction (P > 0.05) between Eimeria and sex on any measurement. Whereas there were no intestinal lesions in unchallenged birds, Eimeria resulted in lesion score (0 to 4) of 3.35, 2.59 and 0.11 in duodenum, jejunum and ileum, respectively. Eimeria challenge decreased (P < 0.05) tibia AC and AP by 10 and 8.2%, respectively but had no (P > 0.10) effect on femur attributes. Generally, males showed (P < 0.05) longer and wider bones with more AC compared with the female. Circulating serum RANKL concentration increased (P = 0.017) in response to Eimeria challenge and was negatively correlated with tibia AC (–0.731; P = 0.021). Our findings showed that Eimeria damage to the intestinal physiology had adverse effects on long bone attributes linked to increased resorption.

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. Tomeet 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. Global Animal Partnership, Canada First Research Excellence Fund, Ontario Agri-Food Innovation Alliance, and Protekta

A total of 672 one-d-old Ross 308 (mixed gender) broiler chicks with an average initial body weight of 34.1 ± 0.2 g were used in a 28-d feeding trial to investigate the effect of supplementing low energy diets with an emulsifier or multi-enzyme complex on broiler. Chickens were allocated to one of six treatments with seven pens/treatment and 16 birds/pen. Treatments were (1) PC (basal diet), (2) NC (PC-100 kcal ME/kg), (3) L05 (NC + 0.05% emulsifier), (4) L10 (NC + 0.10% emulsifier), (5) E05 (NC + 0.05% multi-enzyme), and (6) E10 (NC + 0.10% multi-enzyme). Results showed that supplementing low energy diet with 0.10% multi-enzyme or 0.10% emulsifier improved (P

A total of 864 1-day-old Ross 308 broiler chickens with an average body weight of 40 ± 1.1 g were used to determine the effect of adding protease to broiler chickens diets with different crude protein (CP) density on growth performance, carcase characteristics, excreta microbiota, blood constituents, and nutrient digestibility. The chicks were allotted in pens with 18 birds/pen and 12 pen/treatment. Treatments were T1: basal diet, T2: T1 − 1.0% CP, T3: T2 + 0.05% protease, T4: T2 + 0.1% protease. Results showed that supplementing low CP diets with protease alleviated the negative effects of lowering dietary CP on BWG and FCR (P

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 0.05) 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

Growth performance and physiological responses of feeding modified soy protein concentrate (MSPC, 72% CP) in the starter phase were investigated. A total of 1,216 d old male Ross x Ross 708 broiler chicks were placed in 32 floor pens based on BW, fed one of 4 (n = 8) corn-soybean meal-based diets formulated with 0, 7.7, 10.0 or 12.5% MSPC for 10 d and transitioned to common diets to d 42. Feed intake, BW, and mortality were measured. Samples of birds were bled on d 10 for plasma uric acid (PUA) and subsequently necropsied for organs weight and samples of pancreatic tissues for enzyme activity, jejunal tissues for enzyme activity and histomorphology and ceca digesta for microbial activity. Litter moisture was determined on d 36 and 42 and sample of birds were necropsied on d 42 for breast yield and ceca digesta sample for microbial activity. Feeding MSPC linearly (P < 0.001) increased starter growth performance. Overall (d 0–42), MSPC linearly (P = 0.05)improved FCR; The FCR was 1.566, 1.535, 1.488 and 1.527 for 0.0, 7.7, 10.0, and 12.5% MSPC, respectively. Feeding MSPC linearly (P ≤ 0.04) increased breast yield and decreased small intestine length, gizzard digesta pH, and PUA. Breast yield was 230, 238, 246, and 252 g/kg BW for 0.0, 7.7, 10.0, and 12.5% MSPC, respectively. Pancreatic and jejunal chymotrypsin and trypsin activities and histomorphology were not (P > 0.10) influenced by the diets. On d 10, MSPC linearly (P < 0.05) reduced ceca digesta abundance of Ruminococcaceae, E. Coli, and Clostridium but increased abundance of Bifidobacterium and the ratio of Lactobacilli and E. Coli. Birds fed MSPC showed linear (P = 0.01) increase in abundance of Bifidobacterium on d 42. Feeding MSPC linearly increased ceca digesta acetic (P = 0.01) and reduced propionic (P = 0.048), and iso butyric (P = 0.003) in 10 d old broiler chicken. In conclusion, up to 12.5% MSPC inclusion in the starter phase increased growth performance through to d 42 linked to enhanced gut health through reduction of enteric pathogens.