How do I implement FAMACHA scoring and refugia-based parasite management in small ruminants?

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FAMACHA scoring combined with refugia-based targeted selective treatment (TST) is the recommended integrated approach for gastrointestinal nematode management in small ruminants, slowing anthelmintic resistance while maintaining production. --- FAMACHA scoring assesses anemia severity by examining the color of the lower palpebral conjunctiva on a 1–5 scale, where scores 1 and 2 indicate healthy animals, score 3 represents a borderline condition, and scores 4 and 5 indicate severe anemia.34 The system was developed specifically to detect clinical anemia associated with Haemonchus contortus infection and guide selective anthelmintic treatment.5 Treatment thresholds depend on the clinical context and the performance metric being optimized. Using a FAMACHA cutoff of ≥3 to define animals requiring treatment maximizes sensitivity for detecting anemia (96.4% in camelids at PCV ≤15%), while a cutoff of ≥4 maximizes specificity (94.2% at PCV ≤20%).10 In small ruminants, when FAMACHA score ≥3 is used as the anemia threshold, false negatives are 5.9% in goats and 12.5% in sheep.13 Specificity reaches 100% when FAMACHA score ≥4 is used as the anemia cutoff, though sensitivity drops to 35.29% in goats and 25% in sheep at that threshold.13 FAMACHA scoring should not be used as a standalone indicator in all geographic regions. In New York State, no direct association was found between FAMACHA score and fecal strongyle eggs per gram in either sheep or goats, in contrast to validated performance in the southern US.5 This discrepancy likely reflects regional differences in the proportional contribution of H. contortus relative to other gastrointestinal nematode species, since FAMACHA detects anemia specifically attributable to haemonchosis.5 Combining FAMACHA with additional clinical parameters substantially improves TST accuracy. Animals with FAMACHA score ≥3, body condition score ≤2.5, hemoglobin ≤7.5 g/dL in goats or ≤8.6 g/dL in sheep, packed cell volume (PCV) ≤19.8% in goats or