Pathology of experimentally induced quail bronchitis

Bobwhite quails (Colinus virginianus) were inoculated with 10(6) mean tissue-culture infective dose of quail bronchitis virus at 1, 3, 6, or 9 weeks of age by intratracheal, intraperitoneal, or subcutaneous routes. Quails developed necrotizing tracheitis, proliferative and necrotizing bronchitis and pneumonia; multifocal necrotizing hepatitis; necrotizing splenitis, with or without hyperplasia of splenic mononuclear phagocytes; bursal lymphoid necrosis; and bursal atrophy. Lesions were more extensive and severe in quails inoculated at 1 or 3 weeks of age than in older quails. Large intranuclear inclusions, characteristic of adenovirus infection, were identified in trachea, lung, liver, and bursa of Fabricius. This is the first report of the histopathology of experimentally induced quail bronchitis.     

Effects of basal debris on glacier flow

Glacier movement is resisted partially by debris, either within glaciers or under glaciers in water-saturated layers. In experiments beneath a thick, sliding glacier, ice containing 2 to 11% debris exerted shear traction of 60 to 200 kilopascals on a smooth rock bed, comparable to the total shear traction beneath glaciers and contrary to the usual assumption that debris-bed friction is negligible. Imposed pore-water pressure that was 60 to 100% of the normal stress in a subglacial debris layer reduced shear traction on the debris sufficiently to halt its deformation and cause slip of ice over the debris. Slip resistance was thus less than debris shearing resistance.     

Acute effects of wood-pulp on sockeye salmon (Oncorhynchus Nerka)

Freshwater suspensions of pulp fiber in concentrations exceeding 1000 ppm at 15°C are acutely lethal to sockeye salmon fingerlings. Limited adaptation of such fish to fiber is possible but injury, at least in the short term, is irreversible. The acute lethality of various toxicants associated with industrial pulps is synergistically enhanced by the presence of fiber, and pulp storage up to 158 days at 15°C had no significant effect on the acute lethality. Highly purified fibers are less toxic in fresh than in sea water. The sensitivity to fiber of fish from two sources did not differ significantly.     

Differentiation of physical from chemical toxicity in solid waste fish bioassays

This study showed that particulate (i.e., physical) toxicity was responsible for rainbow trout deaths in bioassays with two separate solid wastes. This conclusion was based on: (1) fish necropsies which indicated physical damage to gills but no evidence of chemical damage to liver or kidney, (2) chemical analyses which indicated that levels of Priority Pollutants and other target compounds were too low to cause the observed toxicity, (3) structural and chemical analyses of the waste particles which showed that these consisted of inert materials, and (4) the use of centrifugation techniques to remove most of the suspended particulate material in bioassay tanks resulting in an elimination of most of the toxicity. The particles associated with the lethal effects were approximately 5 to 10 μm in size. Regulatory testing of solid wastes must distinguish physical and chemical toxicity since disposal options can vary depending on the mode of toxicity. For instance, chemical toxicity raises concern regarding leaching through soils into groundwater, whereas if physical particles are responsible for toxicity, such leaching is not of concern.     

Editorial. The Earth's Biospshere and Its Future

Water, Air, &; Soil Pollution -     

Induction of immunity against infection with Theileria parva (East Coast fever) in cattle using plasma membranes from parasitized lymphoblasts

Protection against challenge with Theileria parva was conferred on three of four calves given three or four inocula of plasma membranes prepared from 6 to 12 X 10(8) autologous parasitized lymphoblasts from cultured cell lines. In contrast, calves remained susceptible to infection following immunization with membranes prepared from allogeneic parasitized lymphoblasts. Similarly, calves vaccinated with either gamma-irradiated autologous or allogeneic infected cells also died of East Coast fever after challenge. The results raise the possibility of vaccination against T. parva using subcellular material from infected lymphoblasts.     

The possible role of weed races in the evolution of cultivated plants

Most of our cultivated plants have companion weed races. This phenomenon is so common that it must have some biological significance. In some cases the weeds are the progenitors of the crops, but in many cases we must look for something that could give rise to both the weed forms and the cultivated form together.The weed races have served as reservoirs of reserve germ plasm, periodically injecting portions of it into the crop under conditions that would most favor increase in variability, heterozygosity and heterosis.Presented at a symposium entitled The Origin and Evolution of Cultivated Plants held during the Tenth International Botanical Congress, 1964. Submitted by J. B. Hutchinson and J. G. Hawkes.