ESR4: Mitigating heat stress effects in poultry production using microbiome programming in ovo

Background

Global climatic change is considered as one of the major environmental threats for broiler chickens. High ambient temperature causes metabolic changes inducing oxidative stress and acid-base imbalance, that subsequently affect the overall performance,health status and meat quality. Perinatal programming is gaining momentum as a strategy to mitigate environmental stressors and shape the resistance of an organism. Such an approach seems to be particularly justified in broilers, because in ovo development (21 days) equals the half of the post-hatch life span (42 days) of the chickens. We hypothesize, that the injection of pre-and/or probiotics at an optimal time point in ovo, can stimulate gut development and immune system, increasing the broiler’s capacity to resist heat stress challenges.

Objectives

  1. Deliver industrial proof of concept targeting heat stress issues by microbiome programming using pre- and/or probiotics delivered in ovo.

  2. Validate the in vitro screening tests to design pre- and/or probiotics targeting heat stress.

Methods

  • Selection of conditions: the pre/probiotics will be selected based on in vitro results and current state of knowledge, and the time point at which heat is disruptive will be provided.

  • Dosage testing: the optimal dosages of the selected pre-and/or probiotics will be determined in ovo, and the presence of probiotic strains in gut will be verified with RT-qPCR.

  • Rearing trial: the selected pre/probiotics will be injected in ovo and HS impact will be applied. The hatched chickens will be randomly allocated up to 8 zootechnical replicates/per treatment group, in an industrial setting. The penned broilers will be sampled for histological studies (gut and muscle tissues), gene expression analysis (GALT tissues including spleen, caecal tonsils, mucosa) and plasma metabolites. Performance traits will be determined weekly (up to 40 d).

  • The penned broilers will be sampled for histological studies (gut and muscle tissues), gene expression analysis (GALT tissues including spleen, caecal tonsils, mucosa) and plasma metabolites. Performance traits will be determined weekly (up to 40 d).

Expected results

  1. The effect of pre-and/or probiotics in ovo on GIT development will be examined (D1.7, D2.9).

  2. Pre- and/or probiotics ameliorating heat stress will be determined (D2.5).

  3. Heat stress effects on physiological and genomic response from in ovo pre- and/or probiotics injected broilers will be assessed (D3.5).

Planned secondments

  • At: FBN (1 mo); Analysis of plasma samples to determine concentrations of amino acids and a large set of metabolites for Objective 1;
  • At: Drobex Agro (1 mo); Test dosage based on hatchability and level of pre- and/or probiotics survival in GIT and get hands-on on hatch management for Objective1;
  • At: Vetdiagnostica (3 mo); Receive industrial training covering production evaluation scheme from hatchery to farm including practical aspects like veterinary diagnostics and onset on farm for Objective 2.

Enrolment in Doctoral degree:

ESR4 will be enrolled at the Department of Animal Biotechnology and Genetics, Faculty of Animal Breeding and Biology of PBS.

Supervisors