Numerous investigations of light induced avian buphthalmia using incandescent light have not defined an etiology. Chickens raised from 2 weeks of age in continuous fluorescent light developed shallow anterior chambers and buphthalmos within the first month of treatment. Chickens raised in continuous fluorescent light developed ocular enlargement similar to that reported in chickens raised in continuous incandescent light. Corneal diameters and axial globe lengths were an inconsistent means of documenting ocular enlargement. Iridocorneal angles were narrowed on scanning electron microscopy.

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During a 2 1/2 year study on the effect of experimentally-induced infectious bursal disease (IBD) in White Leghorns, a system for scoring microscopic lesions was developed. Microscopic changes in the bursa of Fabricius, thymus, spleen, and kidney were studied to create a lesion score for each organ. No changes occurred in the cecal tonsil and few, if any, changes occurred in the liver. The system was useful in evaluating the severity of pathologic and inflammatory changes in each organ during the course of the disease. Lesion scores for the bursa ranged from 0 for normal bursae to +4 for severely affected bursae. The lesion scores for the thymus, spleen, and kidney ranged from 0 to +3. The criteria for scoring lesions in the thymus were: 0 equaled no change; +1- cortex had a few empty spaces, pronounced hyperemia with some heterophil infiltration, especially in the medulla; +2- cortex had an increase in the number of empty spaces and increased heterophil infiltration, and the cortex and medulla had decreased hyperemia; +3- cortex had numerous round aggregations (12 to 16 mu in diameter) of cell debris and pyknotic nuclei, a definite decrease in the lymphocyte density in the cortex, and decreased hyperemia in cortex and medulla. This lesion scoring system was useful in determining the severity of IBD in different-aged progeny from IBD-immune and nonimmune dams.

Eighty-four Single-Comb While Leghorn laying hens housed individually in laying cages were fed rations containing less than 0.1 p.p.m. of dieldrin, DDT, heptachlor and mirex individually or in combination for 7 days and in combination for 15 weeks. DDT residues in egg yolk reached 0.043 p.p.m. by 7 days when fed in combination with the other pesticides. None of the residues were above FDA action level at 7 days and all had declined to below trace levels by 8 weeks after termination of pesticide feeding. Residues in eggs from hens fed all four pesticides for 15 weeks increased steadily for the first few weeks and then reached a plateau or increased only slightly until pesticide feeding was terminated. By the end of the 5th week of pesticide feeding all pesticides except DDT had exceeded FDA action levels for pesticides in eggs. DDT residues reached a level of 0.139 p.p.m. by 8 weeks and did not increase thereafter. Traces of the pesticides were still present 24 weeks after termination of pesticide feeding. The pesticides tested did not affect fertility of hatchability of eggs collected during the 14th and 15th weeks of pesticide feeding. Total carcass fat of chicks hatched from these eggs had 0.024 p.p.m. dieldrin, .049 p.p.m. DDT, .001 p.p.m. heptachlor epoxide and, 0.47 mirex at 1 day of age.

Water consumption of birds and moisture content and water-holding capacity of feces were determined for caged immature broiler breeder males of Strains A and B. Both strains were fed a commercial type corn-soy diet containing 16% protein and .35% sodium chloride. The breeder males of Strain A were also fed different levels of dietary proteins (12, 14, 16, and 18%) for 3 weeks and sodium chloride (0, .17, .35, and .70%) for 3 weeks to evaluate the effect on the criteria listed. A commercial type feeding and water restriction program was used. Strain A males consumed more water and had a significantly greater moisture content and a significantly reduced moisture-holding capacity of feces than did Strain B males when fed the same diet. The dietary levels of salt used had no effect on water consumption (off feed day), fecal moisture, or water holding capacity of the feces in strain A males. Water consumption on feed day significantly increased as dietary salt increased. Although decreasing dietary protein below 16% had no influence on water consumption, it did significantly decrease fecal moisture and increase the water-holding capacity of feces. It was concluded that strain differences in water consumption exist and that the large quantity of water consumed and high fecal moisture content of Strain A males was not related to dietary salt or protein.