Influence of the early use of antibiotic on gut microbiota development, immune response and incidence of diarrhea in neonate heifers

Author(s)

Camila Cecilia Martin

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
• Defense date: 2017-08-25

Examining board members

Viviani Gomes; Mario Julio Avila Campos; Júlio Augusto Naylor Lisbôa

• Advisor: Viviani Gomes

Abstract

The general goal of this research was to evaluate the influence of early antimicrobial use in the gut microbiota, immune response and occurrence of diarrhea in neonate heifers. It was screened 26 neonate Holstein heifers distributed according to the application (ATB+) or not (ATB-) of tulathromycin (2.5mg/Kg - SC) from birth until 12 hours of life. Chapter 1 This chapter evaluated the influence of early use of antimicrobial in the health of neonate Holstein heifer by general clinical examination. Diarrheas were detected using score system and fecal dry matter (%), besides of respiratory score and external palpation of navel region. The performance of calves was evaluated by daily weight gain. Heifers ATB- had high frequency of paleness mucous (P=0.066) and umbilical inflammation in ATB- group on D3-5 (P=0.063) and D13-15 (P= 0.066). The frequency of fecal score 2 and 3 was similar between groups, observing peak of diarrhea on D13-15. The mean values of fecal dry matter were low in ATB+ group on D7-9 (P=0.063) and D27-30 (P=0.084). The main etiologic agent of diarrheas was Cryptosporidium and/or rotavírus. The daily weight gain (DWG) was similar between groups, observing intense decrease of DWG on D13-15. Chapter 2 The aim of this chapter was to evaluate the influence of early use of antimicrobial in the microbial gut colonization by detection of genetic bacterial material using real time PCR. It was not found difference between groups for total bacteria and C. perfringens. The calves from ATB- group had high quantity of Bifidobacterium in the fecal material on D3-5 (P=0.002) and D7-9 (P=0.018). The Lactobacillus population had a tendency (P=0.097) to have high number of DNA copies in the ATB- group. On the other hand, Escherichia coli had tendency to high values in ATB+ group on D20-23 (P=0.052) and D27-30 (P=0.072). Chapter 3 The aim of this chapter was to evaluate the influence of early use of antimicrobial in the inflammatory profile of neonate Holstein heifers by hematological, immunological and biochemical tests, besides electrophoresis. It was possible to observe lower values of hemoglobin (P=0.071), CHCM (P=0.057) and serum iron (P=0.051) in ATB- group on D3-5. In this moment, the frequency of anemia also was high in ATB- group (P=0.016). The number of neutrophils (P=0.051) and spontaneous ROSs was high in ATB- group, while the number of lymphocytes was high in ATB+ group (P=0.061) on D7-9. These data were according to immune analysis, where the proportion of mononuclear population 1 and 2 expressing CD62L+ had a tendency for high values in ATB+ group on D3-5 (P=0.098) and D7-9 (P=0.083). After diarrhea (D13-15), granulocytes (P=0.043) and mononuclear cells (P=0.089) showed high fluorescence intensity of CD62L in ATB+ heifers on D20-23. ATB+ group also had high rate of beta globulin (P=0.057), gamma globulin (P=0.069) and haptoglobin (P=0.032) on D13-15. The early use of tulathromycin had influence on gut microbiota, innate immunity and occurrence of disease in the neonatal period. (AU)

• FAPESP's process: 15/16981-6 - INFLUENCE OF ANTIBIOTICS USE IN EARLY DEVELOPMENT OF GUT MICROBIOTA, IMMUNE RESPONSE AND IMPACT OF DIARRHEA IN NEWBORN CALVES
• Grantee: Camila Cecilia Martin
• Support Opportunities: Scholarships in Brazil - Master