Tick Infestations in Extensively Grazed Cattle and Efficacy Trial of High-cis Cypermethrin Pour-on Preparation for Control of Ticks in Mvomero District in Tanzania
A study, which assessed 1200 short horn Zebu, discovered high tick infestations in extensively grazed cattle in the Mvomero district in Tanzania.The study also looked at the efficacy of Ecotix acaricide (2.5 per cent high cis cypermethrin).
A total of 1200 Tanzanian short horn Zebu (TSHZ) from two farms in two villages were qualitatively assessed for tick infestations and 40 animals (grouped in 10s from each farm) were separated in their herds and quantitatively examined to establish the tick load.
The animals were grouped in treatment regime groups (TxRG 1, 2, 3, and 4), TxRG 1 being the control group was treated with water.
Ecotix® was applied on day 0 for TxRG 2, days 0 and 7 for TxRG 3 and days 0, 7 and 14 for TxRG 4 and tick load was monitored for 28 days.
Results
All the animals examined were infested with ticks. The identified ticks were Rhipicephalus appendiculatus (55%), Amblyomma variegatum (18%), R. (Boophilus) microplus (12.9%), R. (B) decoloratus (7.1%), R. evertsi evertsi (4.4%) and R. composites (2.6%). The overall mean (mean ± SEM) tick density on day zero was 63 ± 30 ticks per animal (ranging from 20–160). The mean tick density on day zero was 44.6 ± 25.4, 74.6 ± 30.3, 55.0 ± 26.2 and 77 ± 33.5 for groups one, two, three and four respectively. Post-treatment quantitative assessment of tick burden revealed that the TxRG 1 animals maintained a tick load throughout the study period. A significant decrease in tick load in animals in groups TxRG 2, 3 and 4 (P=0.0001) with increasing frequency of Ecotix® application was recorded. There was however no significant difference in tick reduction between TxRG 3 and 4 (P=0.0986). Thus TxRG 3 would be sufficient for the monthly tick treatment and with this regime, the farmer would save up to 2.5 USD per animal during six months of dry season.
Total Number of Tick Species Identified in 40 Cattle on Day 0 of the Experiment | ||
---|---|---|
Tick species | Total number of ticks counted | Percent |
R. appendiculatus | 1354 | 55.0 |
A. variegatum | 394 | 18.0 |
R. (B) microplus | 318 | 12.9 |
R. (B) decoloratus | 175 | 7.1 |
R. evertsi evertsi | 109 | 4.4 |
R. compositus | 63 | 2.6 |
Total | 2462 | 100 |
Conclusions
The study revealed a high tick infestation among the TSHZ kept in extensive grazing systems in Mvomero district and that when treated with Ecotix® as pour-on preparation using a two application regime per month, the tick control strategy was effective.
December 2012