High morbidity associated with an outbreak of tick‐borne disease in a dairy herd, Cornwall

Abstract

In April 2020, animals in a herd of 180 dairy cows began displaying pyrexia, milk drop and condition loss. Some animals aborted while others developed anaemia and redcoloured urine. Copious ticks were noted on affected animals. Blood smear examination performed on sick animals detected piroplasms within erythrocytes, and a panpiroplasm PCR and sequencing confirmed the presence of Babesia divergens. Further PCR testing detected Anaplasma phagocytophilum in some of the animals. In a number of animals, co-infection with both pathogens was demonstrated. A range of control measures were implemented with varying levels of success, and clinical cases continued until winter housing of cows in November. A total of 61 animals were affected. The main contributory factor in this case was likely buying in of large numbers of naïve animals into an endemic tick area. Co-infection also potentially increased severity of disease. The difficulties in controlling this outbreak are discussed. CASE PRESENTATIONThis outbreak occurred in a milking cow dairy herd with 180 Holstein-Friesian animals, located near Bodmin Moor in Vet Rec Case Rep.

Anaplasma phagocytophilum Ecotype Analysis in Cattle from Great Britain

“…To the best of our knowledge, this is the first study to demonstrate the presence of ecotype I in cattle and red deer in GB. Bovine anaplasmosis and co-infection with B. divergens and A. phagocytophilum characterized by severe disease and mortality has been reported in GB [ 16 , 32 ] and other parts of mainland Europe [ 29 , 30 , 31 ]. Although this study did not test for Babesia species, B. divergens is known to share the same vector ( I. ricinus ) as A. phagocytophilum and co-infection can increase the severity of disease [ 16 ].…”

“…Gandy et al [ 17 ] and Bianchessi et al [ 18 ] examined questing ticks and sheep, respectively. However, cases of bovine anaplasmosis [ 29 , 30 ] and co-infection with Babesia and A. phagocytophilum resulting in severe disease have been recorded in GB and Europe [ 16 , 31 , 32 ]. Bovine anaplasmosis is a transient and mild infection characterized by clinical signs such as fever, anorexia, weakness and secondary infection due to immunosuppression [ 33 ].…”

“…Bovine anaplasmosis is a transient and mild infection characterized by clinical signs such as fever, anorexia, weakness and secondary infection due to immunosuppression [ 33 ]. High morbidity associated with abortion and a drop in milk production, resulting in economic losses, have also been reported in dairy cattle diagnosed with bovine anaplasmosis [ 32 , 33 , 34 ]. However, information regarding the potential role of A. phagocytophilum in the pathogenesis and diagnosis of abortions and stillbirth in cattle is not clearly known [ 34 ].…”

Sequences Related to Chimay Rhabdovirus Are Widely Distributed in Ixodes ricinus Ticks across England and Wales

“…The property consists of a series of south-facing fields, three are improved pastures, whilst the fourth is an area of rough grazing adjacent to a river. The dairy herd had repeatedly been infected with a number of tick-borne diseases [ 10 ]. Ticks were sampled from four fields in April 2021 using the flagging method and stored in EtOH before processing.…”

Anaplasma phagocytophilum strain analysis in cattle from Great Britain

“…Gandy et al, [17] and Bianchessi et al,[18] examined questing ticks and sheep, respectively. However, cases of bovine anaplasmosis [29,30] and coinfection with Babesia and A. phagocytophilum resulting in severe disease have been recorded in GB and Europe [16,31,32]. Information on A. phagocytophilum ecotypes present in GB cattle is currently unavailable, the aim of this study was to investigate A. phagocytophilum strains present in GB cattle in samples obtained from southern England, Wales, and Scotland.…”