In ovo injection of ascorbic acid and higher incubation temperature modulate blood parameters in response to heat exposure in broilers

Author(s)

Sgavioli, S. ^[1] ; De Almeida, V. R. ^[2] ; Matos Junior, J. B. ^[2] ; Zanirato, G. L. ^[2] ; Borges, L. L. ^[2] ; Boleli, I. C. ^[2]

Affiliation

^[1] Brazil Univ, Anim Prod Master Program, Descalvado, SP - Brazil

^[2] Sao Paulo State Univ, Fac Agron & Vet Sci, Dept Anim Morphol & Physiol, Jaboticabal, SP - Brazil

• Document type: Journal article
• Source: BRITISH POULTRY SCIENCE; v. 60, n. 3, p. 279-287, MAY 4 2019.
• Web of Science Citations: 1

Abstract

1. This study analysed whether in ovo injection of ascorbic acid before incubation and at high incubation temperature influenced blood characteristics and performance in broilers reared in different temperature conditions.2. A total of 3,000 fertile eggs from broiler breeders (Cobb (R)) were randomly divided into three incubation treatments: no ascorbic acid injection and egg incubation at 37.5 degrees C (control); no ascorbic acid injection and egg incubation at 39 degrees C; in ovo ascorbic acid injection prior to incubation (6 mu g AA/100 mu l water) and egg incubation at 39 degrees C.3. Male chicks hatched from the three incubation treatments were submitted to three distinct rearing temperatures (control, cold and hot) from the third week of age onwards (540 chicks were divided into 6 treatments with 5 replicates per treatment).4. Measurements at 42d showed that, after egg incubation at 39 degrees C, the haematocrit, haemoglobin values, ionised calcium and glucose concentrations were increased and base excess values were reduced. However, in ovo injection of ascorbic acid normalised all these parameters.5. Partial CO2 and O-2 pressure were higher with increased rearing temperature. Blood pH was lower when eggs were incubated at 39 degrees C and injected with ascorbic acid. In ovo injection of ascorbic acid induced leucocytosis due to lymphocytosis and heterophilia, restored basophils rate and led to monocytopoenia. Leucocytosis was triggered by hot rearing temperature due to lymphocytosis, eosinophilia and heterophilia.6. The results obtained in this study showed that in ovo injection of ascorbic acid before incubation may serve as a long-term stimulator and modulator of the broiler immune system, and that high incubation temperatures induce adaptations in the electrolytic balance, minimising or avoiding the occurrence of respiratory alkalosis under hot rearing temperature. (AU)

• FAPESP's process: 10/15280-0 - Effects of thermal stress and ascorbic acid injection in the incubation on growth, and physiological and behavioral responses of broilers reared under cold, thermoneutral and heat temperature
• Grantee: Isabel Cristina Boleli
• Support type: Regular Research Grants
• FAPESP's process: 10/01923-7 - EFFECT OF THE INJECTION OF ACID ASCÓRBICO AND CALORIC STRESS IN THE INCUBATION ON THE PERFORMANCE AND CHARACTERISTICS PHYSIOLOGICAL AND BEHAVIOR OF BROILERS REARING ON DIFFERENT TEMPERATURES
• Grantee: Sarah Sgavioli
• Support type: Scholarships in Brazil - Doctorate