Effect of Tasco® on Fecal Egg Counts and Packed Cell Volume in Meat Goats

Abstract Text: The effect of Tasco® on goat gastrointestinal nematode parasite fecal egg counts (FEC) and packed cell volume (PCV) was investigated in two experiments (Exp) using Boer and Boer crossbred goat kids. In Exp 1, female goats at 264 ± 2.5 days of age and 31 ± 0.99 kg BW were artificially infected with 2000 L3 Haemonchus Contortus every other day for 6 d. At 56 days post-infection, 20 goats were assigned to treatments of Control (Con) or Tasco® (TA), n=10/treatment. For Exp 2, 36 naturally-infected, 119 ± 2.4 day old female and castrated male goats at 22.5 ± 0.4 kg were assigned to Con and TA (n=18/treatment). Pre-treatment FEC and BW means were similar. Goats were individually housed in 1.5 x 1.5 m pens with ad libitum water access. A commercially pelleted 17% CP meat goat feed was used. For Exp 1, goats were fed Tasco at 2% feed offered or a similar amount of their daily feed ration (2% BW with  coccidiostat) mixed with 20 ml corn oil 2-3 hours pre-feeding for 14d. For Exp. 2, Tasco was added at 2% DM by the feed company prior to pelleting (no coccidiostat). Both TA and Con pre-weighed rations were fed daily to allow for 10% orts for 21d. Goats were weighed on d 0 and 21 (Exp 2) and fecal sampled at d 0, 7, and 14 (and d 21 for Exp 2) for FEC by modified McMaster’s technique. Percentage PCV was measured in jugular blood samples on d 0, 7, 14 and 21 (d 0 and 14 only for Exp 1). Orts were weighed on d 7 (Exp 1 and 2), and d 14 and 21 (Exp 2). For Exp 1, half the goats regularly left unconsumed Tasco. However, analyzed separately (consumed all vs part) or together, FEC was not impacted by TA, while PCV was higher (P < 0.01) for TA (33.3 ± 0.56%) than Con (30.3 ± 0.58%). For Exp 2, FEC (1820 ± 156 epg), PCV (29.6% ± 0.4%), ADG (0.15 ± 0.02 kg) and FE (0.19 ± 0.02 kg gain/kg feed) were not impacted by TA. Pre-treatment fecal larval identification indicated 84.5% H. contortus. Intake was not influenced by TA. Overall, Tasco® addition to the diet did not have consistent effects on PCV and FEC in goats and did not impact growth or feed efficiency.

Keywords: goat, parasites, Tasco