‘Progressive ataxia’ in a Charolais steer in New Zealand

Extract

Signs of progressive central nervous system disease in cattle aged 2 years and older should alert farmers and veterinarians to consider the possibility of bovine spongiform encephalopathy (BSE). Government veterinarians routinely assess all livestock slaughtered in meat plants in New Zealand for signs of any nervous disorder, including abnormalities of behaviour and mental state and abnormalities of posture and gait.     

GONG Observations of Solar Surface Flows

Doppler velocity observations obtained by the Global Oscillation Network Group (GONG) instruments directly measure the nearly steady flows in the solar photosphere. The sun's differential rotation is accurately determined from single observations. The rotation profile with respect to latitude agrees well with previous measures, but it also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the sun reveal the torsional oscillation signal-weak, jetlike features, with amplitudes of 5 meters per second, that are associated with the sunspot latitude activity belts. A meridional circulation with a poleward flow of about 20 meters per second is also evident. Several characteristics of the surface flows suggest the presence of large convection cells.     

Natural and experimental pox virus infection in the domestic cat

Three naturally occurring cases of cowpox virus infection in the domestic cat are described. Isolate L97 was identified as cowpox virus on the basis of morphology, serology and characteristic cytopathic effect in tissue culture and on the chorioallantoic membrane of embryonated eggs. All three cases showed multiple skin lesions, slight conjunctivitis or purulent ocular discharge but there were no respiratory signs. Two animals recovered, the third was put down as a stray. The disease was reproduced in experimental cats. Isolate L97 was inoculated into two cats intravenously and two cats by skin scarification. All four developed skin lesions at the site or sites of inoculation, and in one cat multiple lesions developed. The two intravenously inoculated animals also developed severe oedema of the neck and brisket around the site of inoculation into the jugular vein, and one cat died. Serological and pathological findings on both the natural and experimental infections are described. Serum neutralising antibody titres in both natural and experimental early convalescent cases were significantly enhanced by the addition of complement.     

Lactose synthetase: progesterone inhibition of the induction of alpha-lactalbumin

Lactose synthesis in the mammary gland is dependent on the hormonally controlled synthesis of the two protein components of lactose synthetase, alpha-lactalbumin and a galactosyltransferase. Prolactin induces the synthesis of both proteins in mammary gland explants treated with insulin and hydrocortisone, but the induction kinetics cannot account for the asynchronous synthesis of the two proteins that are observed in vivo. Progesterone appears to take part in the control of lactose synthesis and acts to repress the formation of alpha-lactalbumin throughout pregnancy. At parturition, when the concentration of progesterone in the plasma decreases, the rate of alpha-lactalbumin synthesis increases.     

Seroprevalence of Japanese encephalitis virus and risk factors associated with seropositivity in pigs in four mountain districts in Nepal*

Japanese encephalitis was recently reported from individuals in the mountain districts of Nepal without travel history to Japanese encephalitis virus (JEV) endemic areas. We performed a cross-sectional study to estimate the seroprevalence of JEV in pigs and subsequently conducted a survey of farmers to identify risk factors associated with seropositivity. In July and August, 2010, 454 pig serum samples were collected and tested by competitive ELISA. Data from a 35-question survey of 109 pig owners were analysed using multivariate logistic regression. Seventy-six (16.7, 95% CI 13.6-20.4) pigs tested positive for anti-JEV antibodies, none of which had been vaccinated against JEV or sourced from JEV endemic areas. Risk factors associated with JEV seropositivity were 'summer abortion', 'wells as a water source', 'urban location', 'reported presence of mosquitoes' and 'lower elevation'. Our results suggest that JEV is likely circulating in the mountain districts of Nepal, and that locally acquired JEV should be considered a risk for residents and travellers in these areas.     

A comparision of the competitive effects and nutrient accumulation of fat‐hen and groundsel

The competitive effects of fat‐hen (chenopodium album L.) and groundsel (Senecio vulgaris L.) on tomato (Lycopersicon esculentum Mill), lettuce (Lactuca sativa L.) and cabbage (Brassica oleracea L. var. Capitata) were investigated under glasshouse conditions. Weed competition severely reduced growth of the three food crops, the reduction being more pronounced with the longer exposure to the competition. Chenopodium album and 5. vulgaris were considerably different in their competitive abilities, although similar differences among the three food‐crop species were found. Senecio vulgaris was affected more by the competition than C. album and had lower tissue concentrations of N, K, and Mg. Growth of both weeds was greatly suppressed when tomato emerged two weeks earlier than the weeds, but the crop plants were severely stunted when the weeds had two weeks initial advantage. It appeared that C. album competed with the three food crops more for K than other elements, while S. vulgaris competed better for P. Cabbage was more competitive with both weed species than tomato while lettuce was the least competitor. Some aspects of these differences in competitive ability among the species could be related to their nutrient use.     

Cytoplasmic substitution inSolanum. II. Tuber characteristics of reciprocal backcross progeny

Summary Recurrent backcrosses (BC) were used to introduce nuclear factors ofS. tuberosum L. ssp.tuberosum into the cytoplasm of Andean potatoesS. tuberosum ssp.andigena (Juz. and Buk.) Hawkes andS. phureja Juz. and Buk. Each generation BC was produced in reciprocal directions to test the effect of cytoplasmic substitution on yield. This report analyses tuber number, tuber weight, and tuber length of BC₂ and BC₃ substitution into ssp.andigena cytoplasm and BC₂ and BC₂ substitutions intoS. phureja cytoplasm. Direction of cross had no consistent significant effect on yield components of ssp.andigena substitution lines. InS. phureja reciprocal progenies direction of cross was responsible for significant differences of some reciprocal sets. When there were significant differences the higher yield usually occurred when ssp.tuberosum was the pistillate parent, but in some progenies when ssp.tuberosum was the pistillate parent the yield was significantly lower than in the reciprocals. It is suggested that differences between reciprocals resulted from chromosomally encoded gene action, resulting from maternal and/or paternal effects, rather than cytoplasmic factors. Authorized for publication as paper No. 7494 in the Journal Series of The Pennsylvania Agriculture Experiment Station.