|Whitley, N -|
|Miller, J -|
|Cazac, D -|
|O'Brien, D -|
|Dykes, L -|
|Muir, J -|
Submitted to: Small Ruminant Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 30, 2009
Publication Date: November 1, 2009
Citation: Whitley, N.C., Miller, J.E., Burke, J.M., Cazac, D., O'Brien, D.J., Dykes, L., Muir, J.P. 2009. Effect of high tannin grain sorghum on gastrointestinal parasite fecal egg counts in goats. Small Ruminant Research. 87(1-3):105-107. Interpretive Summary: Gastrointestinal nematodes represent a major health challenge to small ruminants and effective alternatives to chemical dewormers are needed for organic production. Grazing sericea lespedeza, rich in condensed tannins, is known to reduce fecal egg counts in goats but, it is not known whether other high condensed tannin-rich feeds can do the same. Scientists at University of Maryland-Eastern Shore, Louisiana State University, USDA, ARS in Booneville, AR, Delaware State University, and Texas Agri-Life determined that feeding high condensed tannin sorghum did not influence gastrointestinal nematode infection in goats. This information is important to producers, extension agents, veterinarians, organic certifiers, and scientists.
Technical Abstract: The objective of three experiments was to determine the influence of high condensed tannin (CT) grain sorghum on gastrointestinal parasite fecal egg counts (FEC) in goats. Sixteen naturally-infected Boer crossbred mixed sex goats were used at 124 plus minus 2.9 days of age in Experiment 1, 24 mixed sex goats at 160 plus minus 3.6 days of age in Experiment 2, and 24 male goats at 259 plus minus 3.0 days of age in Experiment 3. Animals that were supplemented with grain daily were removed from pasture and placed in individual pens and fed treatment diets for 21 (experiment 1 and 2) or 14 days (experiment 3). Goats were allowed ad libitum access to water and diets designed containing cracked grain sorghum (high or low CT varieties with equal numbers of goats fed each diet). Packed cell volume (PCV), FEC and FAMACHA® eyelid color scores (EYE; Experiment 1 only) were recorded on day 0 and then every 7 days for the remainder of the studies. For Experiment 1, percentage of animals dewormed (DE), PCV and EYE were not influenced by treatment and averaged 13.6 plus minus 4.5% (each week), 23.4 plus minus 0.8% and 3.2 plus minus 0.12, respectively for all animals. The FEC were impacted by a treatment by day interaction (P less than 0.02), increasing over time compared to day 0 for control but not high tannin grain sorghum fed animals. As expected, EYE and PCV were negatively correlated (r = -0.45; P less than 0.0005). For Experiment 2, there was no influence of treatment on PCV or FEC, however, there was an effect of day on FEC and PCV (P less than 0.002) in which all animals had higher FEC on day 0 (1956 plus minus 219 eggs/g) than any other sampling day and tended (P less than 0.06) to have lower PCV on day 0 than for day 14 or 21. For Experiment 3, there was no effect of feeding high CT grain sorghum on FEC (2992 plus minus 591 epg) or PCV (25.1 plus minus 0.5%). Although high CT forages such as sericea lespedeza (Lespedeza cuneata) have been found to reduce FEC in small ruminants, in these studies, high CT grain sorghum did not consistently influence FEC and did not impact PCV or number of animals requiring chemical anthelmintic treatment.