Storage time and temperature affect the isolation rate of Mannheimia haemolytica and Pasteurella multocida from bovine bronchoalveolar lavage samples

Abstract Background A microbiological diagnosis is essential to better target antimicrobial treatment, control and prevention of respiratory infections in cattle. Under field conditions, non-endoscopic bronchoalveolar lavage (nBAL) samples are increasingly collected. To what extent the highly variable turnaround time and storage temperatures between sampling and cultivation affect the isolation rate of bacterial pathogens is unknown. Therefore, the objective of this experimental study was to determine the effect of different storage temperatures (0°C, 8°C, 23°C and 36°C) and times (0,2,4,6,8,24,48 hours) on the isolation rate and concentration of Pasteurellaceae in nBAL samples from clinically affected animals.Results Storage at 36°C resulted in a reduced isolation rate already 2 hours after sampling for Mannheimia haemolytica and 24 hours after sampling for Pasteurella multocida . When samples were stored at 23°C, a decrease in M. haemolytica and P.multocida isolation rate was noticed, starting at 24 and 48 hours after sampling, respectively. The presence of microbial contamination negatively affected the isolation of P. multocida in clinical nBAL samples. An increase in concentration of contaminating bacteria was noticed after 24 hours of sampling at a temperature of 36°C and after 48 hours of sampling at a temperature of 23°C.Conclusion Optimal M. haemolytica and P. multocida isolation rates from clinical nBAL samples are obtained after storage at 0°C or 8°C, provided that the sample is cultivated within 24 hours after sampling. The maximum period a sample can be stored without an effect on the M. haemolytica and P. multocida isolation success varies and is dependent on the storage temperature and the degree of microbial contamination.

Download Full-text

Isolation of Bacterial causes of Respiratory Infections in Calves in Smallholder farms in and around Gonder Town, Ethiopia

10.21203/rs.3.rs-69366/v1 ◽

2020 ◽

Author(s):

Tefera Manaye ◽

Pawlos Wasihun Asnake ◽

Ashebr Abraha ◽

Tsegaw Fentie

Keyword(s):

Risk Factors ◽

Respiratory Disease ◽

Pasteurella Multocida ◽

Respiratory Infections ◽

Mannheimia Haemolytica ◽

Nasopharyngeal Swab ◽

Respiratory Pathogens ◽

Isolation Rate ◽

Cross Sectional ◽

Tract Infections

Abstract Background: Bovine respiratory disease (BRD) is considered as the major cause of severe respiratory tract infections in calves. Pasteurellosis is a multifactorial respiratory disease, which mainly affect calves within four weeks of weaning. A cross-sectional study was conducted from October 2017 to April 2018 in and around Gondar town, Amhara Regional State, North West of Ethiopia. The aim of the study was to isolate Mannheimia and Pasteurella species from calves up to six months old, and to assess the associated risk factors with the occurrence of respiratory disease. Sex, age (< 16 weeks and > 16 weeks), body condition status (poor, medium, good), breed (local and cross breed), livelihood (mixed crop and urban), farming systems (semi intensive and intensive), herd size (small medium, and large), maternity pens (present or absent), and method of colostrum feedings (hand bucket and suckling) were the examined risk factors.Results: A total of 84 nasopharyngeal swab samples were collected from calves with any signs of illness related to pasteurellosis. The overall isolation rate of the respiratory pathogens was 64/84 (76.2%) (95% CI=65.7-84.8), with 46.4% of Mannheimia haemolytica and 28.8% Pasteurella multocida isolates. The distribution of pathogens was statistically higher (P< 0.001) in calves with respiratory problems (93.6%; 95% CI= 82.5-98.7) compared to those with no symptoms of respiratory illness (54.1%; 95% CI= 36.9-70.5). Among the examined risk factors age, sex, breed, farming system were found to be potential risk factors and significantly associated with Pasteurella infection of calves (p<0.05). The higher isolation rate of Mannheimia haemolytica indicated that it is the major cause of respiratory disease in the study area.Conclusion: The present finding revealed that pasteurellosis is one of the major diseases of calves in the study area in which M. haemolytica and P. multocida were found to be commonly involved in respiratory infections. Improved farm management including timely feeding of colostrum, appropriate hygiene of the calf house and training of farmers is recommended to prevent and control of respiratory diseases in the study area.

Download Full-text

Storage time and temperature affect the isolation rate of Mannheimia haemolytica and Pasteurella multocida from bovine bronchoalveolar lavage samples

10.21203/rs.2.15872/v3 ◽

2020 ◽

Author(s):

Laura Van Driessche ◽

Charlotte De Neve ◽

Freddy Haesebrouck ◽

Katharina van Leenen ◽

Filip Boyen ◽

...

Keyword(s):

Pasteurella Multocida ◽

Microbial Contamination ◽

Storage Temperature ◽

Turnaround Time ◽

Antimicrobial Treatment ◽

Mannheimia Haemolytica ◽

Isolation Rate ◽

Control And Prevention ◽

Tract Infections ◽

Storage Temperatures

Abstract Background: A microbiological diagnosis is essential to better target antimicrobial treatment, control and prevention of respiratory tract infections in cattle. Under field conditions, non-endoscopic broncho-alveolar lavage (nBAL) samples are increasingly collected. To what extent the highly variable turnaround time and storage temperatures between sampling and cultivation affect the isolation rate of bacterial pathogens is unknown. Therefore, the objective of this experimental study was to determine the effect of different storage temperatures (0°C, 8°C, 23°C and 36°C) and times (0,2,4,6,8,24,48 hours) on the isolation rate and concentration of Pasteurellaceae in nBAL samples from clinically affected animals.Results: At a storage temperature temperature of 36°C isolation rates of Mannheimia haemolytica and Pasteurella multocida were significantly reduced 6h and 48h after sampling, respectively. At room temperature (23°C), a decrease in M. haemolytica and P. multocida isolation rate was noticed, starting at 24 and 48 hours after sampling, respectively, but only significant for P. multocida at 48h. The presence of microbial contamination negatively affected the isolation of P. multocida in clinical nBAL samples, but not of M. haemolytica. Conclusion: Optimal M. haemolytica and P. multocida isolation rates from clinical nBAL samples are obtained after storage at 0°C or 8°C, provided that the sample is cultivated within 24 hours after sampling. The maximum period a sample can be stored without an effect on the M. haemolytica and P. multocida isolation success varies and is dependent on the storage temperature and the degree of microbial contamination.

Download Full-text

Storage time and temperature affect the isolation rate of Mannheimia haemolytica and Pasteurella multocida from bovine bronchoalveolar lavage samples

10.21203/rs.2.15872/v2 ◽

2020 ◽

Author(s):

Laura Van Driessche ◽

Charlotte De Neve ◽

Freddy Haesebrouck ◽

Katharina van Leenen ◽

Filip Boyen ◽

...

Keyword(s):

Pasteurella Multocida ◽

Microbial Contamination ◽

Storage Temperature ◽

Turnaround Time ◽

Antimicrobial Treatment ◽

Mannheimia Haemolytica ◽

Isolation Rate ◽

Control And Prevention ◽

Tract Infections ◽

Storage Temperatures

Abstract Background: A microbiological diagnosis is essential to better target antimicrobial treatment, control and prevention of respiratory tract infections in cattle. Under field conditions, non-endoscopic broncho-alveolar lavage (nBAL) samples are increasingly collected. To what extent the highly variable turnaround time and storage temperatures between sampling and cultivation affect the isolation rate of bacterial pathogens is unknown. Therefore, the objective of this experimental study was to determine the effect of different storage temperatures (0°C, 8°C, 23°C and 36°C) and times (0,2,4,6,8,24,48 hours) on the isolation rate and concentration of Pasteurellaceae in nBAL samples from clinically affected animals. Results: At a storage temperature temperature of 36°C isolation rates of Mannheimia haemolytica and Pasteurella multocida were significantly reduced 6h and 48h after sampling, respectively. At room temperature (23°C), a decrease in M. haemolytica and P. multocida isolation rate was noticed, starting at 24 and 48 hours after sampling, respectively, but only significant for P. multocida at 48h. The presence of microbial contamination negatively affected the isolation of P. multocida in clinical nBAL samples, but not of M. haemolytica. Conclusion: Optimal M. haemolytica and P. multocida isolation rates from clinical nBAL samples are obtained after storage at 0°C or 8°C, provided that the sample is cultivated within 24 hours after sampling. The maximum period a sample can be stored without an effect on the M. haemolytica and P. multocida isolation success varies and is dependent on the storage temperature and the degree of microbial contamination.

Download Full-text