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

Abstract

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.

Effects of a blend of chestnut and quebracho tannins on gut health and performance of broiler chickens

“…Besides experimental trials describing the effects of chestnut and quebracho tannins, efficacy should be contrasted in field/commercial trials under different challenge conditions. However, to our knowledge, only a few studies describing the impact of tannins or others AGP-alternatives in commercial poultry production conditions are available in the scientific literature, and these works reported variable results [15][16][17][18]. In order to overcome limitations in the study of field application of potential AGP alternatives including chestnut and quebracho tannins, multiple approaches are needed to identify products with high effectiveness rate to reduce antimicrobial needs in poultry industry.…”

Comparison of functional-oil blend and anticoccidial antibiotics effects on performance and microbiota of broiler chickens challenged by coccidiosis

“…One important factor to consider is that they do not entirely suppress parasite development, thus allowing the development of host immunity after initial exposure [ 17 , 22 ]. Parent et al [ 23 ] observed that programs that used antibiotics presented similar performance to those that exclusively used ionophores. However, cases of parasite resistance to ionophores have been reported owing to the use of these substances for an extended period [ 22 ].…”

Mandated restrictions on the use of medically important antibiotics in broiler chicken production in Canada: implications, emerging challenges, and opportunities for bolstering gastrointestinal function and health — a review

“…Therefore, the industry is faced with either the possible loss in efficacy of antibiotics or their complete removal from flocks. Processors are faced with some possible challenges associated with the removal of AGP including decreased body weight and reduced flock uniformity however, increased condemnations may not necessarily occur (Engster et al 2002;Smith 2011;Gaucher et al 2015;Parent et al 2020). The degree of processing challenges as they relate to compromised weight and uniformity and incidence of condemnations will be dependent on the occurrence and severity of clinical and subclinical enteric diseases (Kaldhusdal et al 2016).…”

“…There is interest in evaluating bird performance and overall health under commercial farm conditions. This has been supported in academia through the publication of some studies done in commercial settings (Diarrassouba et al 2007;Bray et al 2009;Gaucher et al 2015;Parent et al 2020).…”