Banca de QUALIFICAÇÃO: LUCIANO BRANDALISE

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
DISCENTE : LUCIANO BRANDALISE
DATA : 13/12/2019
HORA: 09:30
LOCAL: IFC Campus Concórdia
TÍTULO:

Evaluation of Mycoplasma hyopneumoniae infection dynamics in negative replacement gilts housed in positive commercial farms

PALAVRAS-CHAVES:

qPCR, serology, laryngeal swab, acclimation.

PÁGINAS: 45
GRANDE ÁREA: Ciências Agrárias
ÁREA: Medicina Veterinária
RESUMO:

Negative Mycoplasma hyopneumoniae (M. hyopneumoniae) replacement gilts provide greater health security to breeding stock. However, in M. hyopneumoniae positive herds, the introduction of gilts present a higher risk for the vertical transmission (piglet-sow) at first farrowing, because the transmission is slow and excretion occurs for an extended period, maintain the disease in the herds. Therefore, this study aim to evaluate the dynamics of M. hyopneumoniae infection in negative replacement gilts housed in positive commercial farms and naturally exposed to the agent. One hundred and twenty gilts, from negative M. hyopneumoniae farms, were housed in three positive commercial farms located in the west of Santa Catarina and the northwest of Rio Grande do Sul. All animals were identified for longitudinal follow-up during the study. At the time of housing the animals were arranged in collective pens, where on at least one side allowed contact between pens with a group of gilts previously housed in the farm. In these animals, no vaccination for M. hyopneumoniae was performed and when necessary, the medication occurred individually with non-effective M. hyopneumoniae antibiotics. Infection dynamics are being assessed by detection of M. hyopneumoniae by real-time qPCR and ELISA antibody detection from the laryngeal swab and blood samples, respectively, collected at the housing (day 0), 15, 30, 60, 90, 120, 150 days of housing and pre-farrowing. For evaluation of possible vertical transmission through nasal swab, piglets will be sampled near weaning. Laryngeal and nasal swab samples will be considered positive in qPCR when Ct ≤ 38.5. Positive laryngeal swab samples with Ct ≤ 31 will be characterized by the multiple locus variable number tandem repeat analysis (MLVA) technique. Serum samples will be classified as positive or negative. Analyzing the preliminary results, we observed variations in the dynamics of infection among the farms. The first PCR detections occurred within the second week after the start of the evaluation. At ninety days of housing, the animals were positive at least once and the negativity of some animals in the PCR samples began. It took at least twenty-eight days of housing for 100% of the gilts to be acclimatized. In serology, the first antibody detections occurred in the second week of housing, but one hundred and fifty days of housing, all animals were positive at least once. Therefore, PCR detection was earlier than ELISA antibody detection. The study is in progress and more analysis will be performed to project finishing.

MEMBROS DA BANCA:
Interna - 1989957 - ALESSANDRA FARIAS MILLEZI
Presidente - 1756086 - DIOGENES DEZEN
Interno - 2017813 - RICARDO EVANDRO MENDES
Interna - 2408296 - SORAYA REGINA SACCO