The use of large databases to inform the development of an intestinal scoring system for the poultry industry

Does supplementing β-mannanase modulate the feed-induced immune response and gastrointestinal ecology in poultry and pigs? An appraisal

The provision of adequate and balanced nutrients is critical for efficient and profitable animal protein production. However, non-nutritive components in feedstuffs can elicit responses that can negatively impact nutrient utilization efficiency. For example, dietary β-mannans are recognizable by cell surface mannose receptors are pivotal for diverse cellular functions. This review will evaluate the physiological implications of dietary native β-mannans, the utility of supplemental feed β-mannanase in hydrolyzing β-mannans, and subsequent metabolic responses. Dietary native β-mannans have been implicated in inadvertent stimulation of immune response through a phenomenon called the feed-induced immune response (FIIR), that has been associated with intestinal inflammation and depression in animal performance. Supplemental β-mannanase blunted the FIIR by hydrolyzing native β-mannans to smaller fragments with a reduced ability to stimulate the innate immune system as indicated by the modulation of oxidative stress, mucosal permeability, and blood concentration of acute phase proteins and immunoglobulins in broilers and piglet models. Moreover, β-mannanase hydrolysis of native β-mannans to mannooligosaccharides (MOS) impacted gastrointestinal microbial ecology. Indeed, β-mannanase-derived MOS reduced the concentration of pathogenic bacteria such as Escherichia coli and Salmonella and increased the production of short-chain fatty acids in gastrointestinal tracts of various animal models. Consequently, by hydrolyzing native β-mannans, supplemental β-mannanase may have nutritional, metabolic, and microbial ecology benefits. In summary, integrating multi-functional feed additives such as β-mannanase into feeding programs for monogastric animals will be critical for efficient and sustainable animal protein production in the context of evolving challenges such as the mandated elimination of use of antibiotics for growth promotion.

Impacts of antibiotic reduction strategies on zootechnical performances, health control, and Eimeria spp. excretion compared with conventional antibiotic programs in commercial broiler chicken flocks

Increasing efforts have been made in recent years to reduce antimicrobial use in animal production. The objective of this prospective study was to evaluate, in commercial broiler chicken farms, 2 antibiotic reduction strategies that eliminated the use of antibiotics important for human medicine, in comparison with the conventional use of antibiotics. On 7 broiler chicken farms, a house was allocated to the antibiotic reduction treatments for 6 consecutive flocks, whereas a similar house on the same premises was assigned to the conventional use of antibiotics (CONV) for 6 consecutive flocks. The antibiotic reduction strategies consisted of continuous in-feed use of ionophores (TX1) and continuous in-feed use of ionophores with butyric acid (TX2). In the 84 flocks, zootechnical performance was recorded, lesion scoring at 21 and 28 D of age was performed, and fecal samples were recovered during grow out for Eimeria spp. oocysts counts. There was no statistical difference between TX1, TX2, and CONV for weights at slaughter, feed conversion ratios, average daily gains, age at slaughter, total mortalities, and condemnations. The probability of identifying oocysts in the fecal samples significantly increased with the age of the flock, but there was no significant treatment effect between 7 and 16 D of age. At 19 D of age, the probability of a sample containing oocysts was higher in TX1 than in CONV, but TX2 was not statistically different from TX1 and CONV. Predicted oocysts per gram in CONV flocks were significantly lower between 22 and 34 D of age than in TX1 and TX2 flocks, whereas there were no significant differences between TX1 and TX2 for all ages. Lesion scoring of the gastrointestinal system showed no differences for coccidiosis scores between TX1, TX2, and CONV. No lesions of necrotic enteritis were observed. In conclusion, it was possible to adequately control intestinal diseases and maintain zootechnical performances by relying exclusively on ionophores, when compared with broiler chicken flocks using standard shuttle programs with antibiotic growth promoters.

A study on risk factors for macroscopic gut abnormalities in intensively reared broiler chickens

Intensification of broiler production has coincided with an increase in enteric disorders. Enteric syndromes of unknown aetiology are often associated with an increased feed conversion ratio and are given the general term "dysbiosis". Despite the importance of dysbiosis, information on factors contributing to this condition are scarce. Therefore, the aim of this study was to describe dysbiosis in broilers (Ross 308) during one production round and to identify risk factors. Fifteen farms in Flanders (Belgium) were followed up, with visits at days 10, 17, 20, 24 and 28 of production. At every visit, 10 random birds were inspected for footpad lesions, hock burns and breast blisters. Also, coccidiosis and enteric abnormalities were scored after necropsy. A gut appearance score (GAS) was given based on 10 macroscopically visible parameters, where a higher GAS equalled more enteric abnormalities. Footpad lesions were seen in 14 farms and increased in prevalence with the age of the birds. Hock burns were seen less frequently, and no breast blisters were detected. Eimeria acervulina lesions were most frequently observed, followed by E. maxima and E. tenella lesions. The average GAS increased from day 10 until day 20. The strong correlations between the GAS at days 10, 17 and 20 indicate that prevalence of gut abnormalities at day 10 can be predictive for scores later on. A higher amount of intestinal defects was seen in older female birds, in the presence of a conceivable E. tenella infection and at farms with a higher productivity and sanitary status.RESEARCH HIGHLIGHTSGut lesions found in young broilers can predict further development of defects.Caecal lesions showed the strongest correlation with GAS in a multivariate model.