Parasite transmission in confined hogs.

Area of Science:

• Veterinary Parasitology
• Swine Health Management
• Livestock Epidemiology

Background:

• Intestinal parasites pose significant challenges to swine health and productivity in confinement operations.
• Understanding parasite prevalence, intensity, and transmission is crucial for effective control strategies.
• Previous research has indicated varying parasite burdens across different swine age groups and production stages.

Purpose of the Study:

• To determine the prevalence, intensity, and transmission patterns of intestinal nematode and protozoan parasites in swine.
• To investigate age- and production-related variations in parasitic infections within a confined swine herd.
• To assess the efficacy of management practices in controlling specific parasitic infections.

Main Methods:

• Conducted a 5-year survey (1977-1981) of fecal specimens from swine of all ages in a South Georgia confinement facility.
• Analyzed fecal samples to quantify parasite eggs per gram (EPG) and cysts per gram (CPG).
• Compared parasite prevalence and intensity across different age groups (nursery pigs, growing-finishing hogs, gilts, sows) and production units (gestation, farrowing).

Main Results:

• Nursery pigs showed minimal infections, primarily sporadic Isospora suis. Growing-finishing hogs had low prevalence of Ascaris suum, Oesophagostomum spp., and Balantidium suis.
• Ascaris suum prevalence and EPG peaked around 200 days of age, then declined, while Oesophagostomum spp. and B. suis prevalence and intensity increased with age.
• Gilts exhibited higher Ascaris suum prevalence and EPG but lower Oesophagostomum spp. and B. suis compared to older sows. No peri-parturient increase in parasite shedding was observed.

Conclusions:

• Parasite dynamics in confined swine are significantly influenced by age, with distinct patterns for different nematode and protozoan species.
• Management strategies should consider age-specific parasite risks, particularly for Ascaris suum in younger swine and Oesophagostomum spp./B. suis in older animals.
• The study identified limited parasite establishment for Trichuris suis and effective control of Strongyloides ransomi through anthelmintics.