Occurrence of Theileria parva infection in cattle on a farm in the Ladysmith district, KwaZulu-Natal, South Africa : article

Theileria parva causes widespread morbidity and mortality in cattle in endemic regions. An outbreak of theileriosis occurred on a farm near Ladysmith in KwaZulu-Natal, South Africa, which is not a declared Corridor disease-infected area. A survey of Red Brangus cattle from all age groups and areas of the farm was performed. Transmission of the parasite from infected animals on the farm to susceptible animals by tick transmission and tick-stabilate injection, was attempted. The survey indicated high numbers of animals with antibody titres to T. parva but only 6 infected animals, based on real-time PCR and RLB analysis. The transmission experiments failed to transmit the parasite. The study shows the difficulty in elucidating a source of infection and determining the dynamics of new infections in a herd where multiple possible sources are present and treatment with tetracyclines has taken place

Two gonadotropin-releasing hormone receptor subtypes with distinct ligand selectivity and differential distribution in brain and pituitary in the goldfish (Carassius auratus)

In the goldfish (Carassius auratus) the two endogenous forms of gonadotropin-releasing hormone (GnRH), namely chicken GnRH II ([His5,Trp7,Tyr8]GnRH) and salmon GnRH ([Trp7,Leu8] GnRH), stimulate the release of both gonadotropins and growth hormone from the pituitary. This control is thought to occur by means of the stimulation of distinct GnRH receptors. These receptors can be distinguished on the basis of differential gonadotropin and growth hormone releasing activities of naturally occurring GnRHs and GnRHs with variant amino acids in position 8. We have cloned the cDNAs of two GnRH receptors, GfA and GfB, from goldfish brain and pituitary. Although the receptors share 71% identity, there are marked differences in their ligand selectivity. Both receptors are expressed in the pituitary but are differentially expressed in the brain, ovary, and liver. Thus we have found and cloned two full-length cDNAs that appear to correspond to different forms of GnRH receptor, with distinct pharmacological characteristics and tissue distribution, in a single species.Articl