SUMMARY: Faecal specimens from diarrhoeic pre-weaned calves (n=61) and lambs (n=127) collected over a 1-year period (2008–2009) at 27 cattle and 28 sheep farms in Galicia (NW Spain) were examined for the presence of Cryptosporidium oocysts and positive specimens were selected for molecular examination. Overall, 30 calves (49·2%) and 39 lambs (30·7%) tested positive for Cryptosporidium by microscopy. PCR products of the SSU rRNA locus were obtained for 27 Cryptosporidium positive calf isolates and 23 lamb isolates. Restriction analyses generated profiles of C. parvum in all isolates except for 9 lamb specimens from 5 farms that yielded banding patterns and sequences indicative of the Cryptosporidium cervine genotype. Sequence analyses of the glycoprotein (GP60) gene revealed that all but 1 C. parvum isolate from calves belonged to the subtype IIaA15G2R1 and 1 isolate was identified as the novel subtype IIaA13G1R1. Two different subtypes were identified in sheep flocks including IIaA16G3R1, which was seen in 7 lamb isolates from a single farm and subtype IIaA15G2R1, identified in 3 isolates from 2 farms. These findings suggest a limited genetic diversity within C. parvum in ruminant livestock from this geographical area, although both calves and lambs should be considered as a reservoir for zoonotic subtypes.

An age-related distribution of Cryptosporidium species has been reported in cattle, with C. parvum being predominant in suckling calves, C. bovis and C. ryanae being predominant in post-weaned calves and C. andersoni being predominant in adults. However, variants to this pattern have recently been reported. Thus, fecal samples (n = 594) from asymptomatic cattle were collected in north-western Spain. Animals were classified as 2 years (G5). Cryptosporidium detection and species identification were performed by SSU rRNA PCR. Individual Cryptosporidium prevalence was 16.7%; it significantly decreased with age. Cryptosporidium parvum was predominant in G1 and C. bovis was predominant in the rest of the age classes; C. bovis and C. ryanae were especially prevalent in G2 and G3. Cryptosporidium occultus was not found in suckling calves. Finally, C. andersoni and C. xiaoi were occasionally detected in G5. The presence of C. parvum in all age classes implies significant animal and public health concerns. The predominance of C. bovis in cattle older than 1 month supports the idea that the age-related pattern of Cryptosporidium species described in cattle is not fully consistent, and thus further studies are still needed to identify those factors determining the species distribution.