Gasterophilus spp. infections in horses from northern and central Kazakhstan

- This is the first study on gastrointestinal parasites of horses in Central Asian countries since the dissolution of the Soviet Union.
- Four Gasterophilus spp. (G. haemorrhoidalis, G. intestinalis, G. nasalis, G. pecorum) were found in northern and central provinces of Kazakhstan.
- All horses were infected with 2nd and 3rd stage larvae throughout the year, indicates that two overlapping generations of botflies exist in the Kazakh steppe during a year.
- The larval burdens were extremely high, and 22% of the horses harboured >1000 Gasterophilus spp. larvae each.

A cross-sectional survey was performed to obtain current data on the gastrointestinal myiasis of horses in the provinces of Kostanay, Akmola and Karagandy, northern and central Kazakhstan. The stomach, small intestine and rectum of 148 slaughter horses were examined for Gasterophilus spp. larvae during a 26-month study period. All horses were infected with 2nd and 3rd stage larvae (mean intensity: 803 ± 350), and 22% of them harboured >1000 Gasterophilus spp. larvae each. Four species were identified: G. intestinalis (prevalence: 100%; mean intensity: 361 ± 240 larvae), G. haemorrhoidalis (100%; 353 ± 191), G. nasalis (100%; 73 ± 36) and G. pecorum (91.2%; 18 ± 10). Horses aged < 2 years were higher infected with Gasterophilus larvae than 2-4 years old animals. Both the prevalence and extremely high intensity of Gasterophilus infections of horses in these Kazakh regions suggest respective control measurements to improve the health and performance of the animals and to increase the economic income of horse owners.