Effect of insecticide treated nets fence in protecting cattle against tsetse and other biting flies in Arba Minch Zuria district, Southern Ethiopia
A field trial was carried out to assess the effect of insecticide treated net in protecting cattle from tsetse and other flies. A total of 35 pens were constructed, out of which 30 of them were fenced with insecticide treated net which served as treatment group and the remaining 5 pens were untreated controls. The fly populations around the pens were monthly monitored for five months using NGU traps deployed 5 m away from the cattle pens. The defensive movements of different body parts manifested by an animal for fly protections were observed for 5 minutes in each of the experimental and control groups. Additionally, other parameters such as packed cell volume, milk yield and body condition scores and buffy coat examination were investigated for both groups. Milk yield, body condition scores, packed cell volume (PCV) and data of defensive movements of animals were analyzed using linear model for longitudinal data or repeated measures by specifying time (monitoring cycles) and cattle as repeated variables. The result of this study showed that the overall proportion of fly catches was significantly lower in treated (38.3%) than control group (61.7%). Similarly, a significantly lower proportion of tsetse flies (28.4% versus 71.6%), biting flies (40.7% versus 59.3) and non-biting nuisance flies (39.7% versus 60.3%) compared to treatment. As a result, animals in treatment group had significantly lower average defensive movements of different body parts (7.84) compared to those in controls (16.37). All animals in both groups were negative for trypanosome infection and and there was no significant difference in their mean PCV values. Significant variation was not observed in daily milk yield between cows in treatment (0.83 liter) and in controls (0.53 liter). Fly densities had showed positive and negative relationships with defensive movements and PCV values over the monitoring time period, respectively. Body condition score of animals in the treatment group was also significantly higher (p<0.05) than those in controls. In conclusion, deltamethrin treated netting was found to reduce the challenges of tsetse and other biting flies, and thus can contribute to improved performances of animals in treatment groups.
Keywords: Cattle; Fly protection; Insecticide treated net; Southern Ethiopia; Zero-grazing