Seasonal Prevalence of Helminthic Infections in the Gastrointestinal Tract of Sheep in Mazandaran Province, Northern Iran

Table 1

The number (percentage) of the observed gastrointestinal parasites.

Genus	Spring	Summer	Fall	Winter	Total
Nematodirus^a	3 (5%)	0	2 (3.33%)	3 (5%)	8 (3.19%)
Trichuris^a	2 (3.33%)	5 (8.33%)	5 (8.33%)	2 (3.33%)	14 (5.58%)
Toxocaridae^a	2 (3.33%)	5 (8.33%)	5 (8.33%)	0	12 (4.78%)
Strongyloides^a	6 (10%)	0	0	0	6 (2.39%)
Haemonchus^b	4 (6.66%)	4 (6.66%)	3 (5%)	1 (1.66%)	12 (4.78%)
Ostertagia^b	3 (5%)	4 (6.66%)	7 (11.66%)	0	14 (5.58%)
Cooperia^b	3 (5%)	3 (5%)	2 (3.33%)	0	8 (3.19%)
Trichostrongylidae^b	32 (53.3%)	33 (55%)	37 (61.6%)	15 (25%)	117 (46.61%)
Oesophagostomum^b	6 (10%)	4 (6.66%)	2 (3.33%)	0	12 (4.78%)
Chabertia^b	5 (8.33%)	3 (5%)	5 (8.33%)	2 (3.33%)	15 (5.98%)
Dicrocoelium^a	6 (10%)	2 (3.33%)	0	0	8 (3.19%)
Fasciola^a	9 (15%)	8 (13.33%)	8 (13.33%)	0	25 (9.96%)
Total	81 (32.27%)	71 (28.29%)	76 (30.28%)	23 (9.16%)	251

^aIdentified by its egg.
^bIdentified by its larvae.