218 
The Aberystwyth Area 
Red Water (Boyish Piroplasmosis). 
“Red Water” is one of the chief troubles of the N. Cardiganshire 
farmer, and there is no doubt that in most cases the cause is tick-borne 
bovine piroplasmosis. • 
I have received sixty complaints and in almost all I ascertained 
that the tick Ixodes ricinus was present, frequently in large numbers. 
Prof. G. H. F. Nuttall has reminded me that “red water” may be 
due to toxic plants, but I am unable to say what plants may be respon¬ 
sible for the trouble within the area surveyed, although it is everywhere 
firmly believed that the disease is due to cattle eating alder ( Gwern ) 
and oak leaves, and farmers insist that outbreaks follow the grazing of 
cattle on or near woodlands or rough swampy places where alders are 
abundant. It is in just such places however, that I. ricinus is most 
common. The rough ferny pastures, rocky hillsides and wooded valleys 
and slopes frequently swarm with this tick, and several farmers state 
that at times the cattle come home so covered with them that they can 
be scraped off, while poultry will pick them off the cattle while standing 
and lying about the yards. Fern cutters are often troubled by the 
ticks and I have come across several cases of sores resulting from their 
careless removal from the flesh. I have extracted a number of the 
hexapod larvae from my own limbs after passing through fern, etc., and 
in September 1915 I captured dozens of these larvae crawling upon 
my hands and arms after handling some dead bracken. I have also 
frequently collected this tick from dogs, cats, sheep, etc. in all parts of 
the area, and it is interesting to note that no case has yet been reported 
to me from the upland pastures and peat lands. It will be seen that 
the affected land includes much of the rough peaty soil of the Dyfi Flats, 
and the wooded valleys. I have known cases due to cattle being turned 
into the woods to graze during May and June, because it was too 
early to send them to the hills, and the lower fields had been closed 
for hay. 
Severe losses have occurred on a number of the infected farms, 
sometimes during the spring and early summer, at. other times in late 
summer and early autumn; the majority of outbreaks being in May— 
June and again in August—September. Several cases have come under 
my notice in which red water farms have changed hands, with the 
result that the new occupier has soon had to deal with a more or less 
violent outbreak generally resulting in severe losses, in one instance 
ten cases and three deaths. 
