Effect of vacuum packing and temperature on survival and hatching of strongyle eggs in faecal samples.

The research investigates the combined effect of vacuum packing and temperature on the survival of strongyle eggs in livestock feces and their subsequent ability to develop into larvae. The study found that vacuum packing and specific storage temperatures have differing effects on different types of helminths.

Study Design and Procedure

• Fecal samples were collected from calves, pigs, and horses knowingly infected with Cooperia oncophora, Oesophagostomum dentatum, and Strongylus vulgaris and cyathostomins, respectively.
• The samples underwent four different treatments: vacuum packed and stored at 5 °C or 20 °C; or packed normally in plastic gloves and stored at the same respective temperatures.
• The eggs per gram of feces (EPG) was measured every fourth day until the 28th day using a concentration McMaster-method.
• Larval cultures were prepared on day 0, 12, and 28 and the larval yield, or the number of larvae developed from the eggs, was determined.

Findings

• For Cooperia oncophora in calves, the EPG was significantly higher in vacuum packed samples after 28 days compared to normal storage, regardless of temperature.
• Oesophagostomum dentatum in pigs had significantly higher EPG in samples kept at 5 °C compared to 20 °C, irrespective of the packing method.
• For Strongylus vulgaris and cyathostomins in horses, vacuum packed samples at 5 °C showed a significantly higher EPG compared to other treatments after 28 days.
• The highest yield of larvae from Oesophagostomum dentatum and horse strongyles came from fresh fecal samples. However, if storage is necessary, Oesophagostomum dentatum samples should be kept at room temperature, irrespective of whether it is under aerobic or anaerobic conditions.
• Horse strongyle samples should be set up for larval culture on the day of collection for maximum yield.
• Eggs of Cooperia oncophora should be kept vacuum packed at room temperature for the highest larval yield.

Conclusion

• The research concludes that the survival and development of strongyle eggs are influenced by packaging and temperature conditions.
• Specific retained conditions are ideal for different types of helminths, suggesting custom strategies should be employed for the preservation and study of specific strongyles.