B. L. Reid

Nature of intestinal phytase activity.

Summary Experiments were carried out with chicks, mature hens and weanling rats fed dicalcium phosphate, calcium phytate and sodium phytate as dietary phosphorus sources. Intestinal phytase activity measurements failed to show a significant difference in the activity of this enzyme due to the dietary treatments. The mature hen exhibited lower intestinal phytase activity than did the chick or the rat. The use of mixed substrates, employing sodium phytate and beta-glycerophosphate at equi-molar concentrations, failed to produce an increase in activity as compared to these substrates singly. These data indicated that the phytase activity may have been due to a non-specific phosphatase in the intestinal homogenates. The ratios of alkaline phosphatase to phytase activities in presence or absence of fluoride were the same. These data also point to the presence of only one enzyme system which hydrolyzed both sodium phytate and beta-glycerophosphate.

The effect of injection of chlorinated hydrocarbon pesticides on hatchability of eggs

Abstract Dieldrin, aldrin, endrin, DDT, heptachlor, toxaphene, endosulfan, lindane, and strobane were injected via a corn oil carrier into fertile hen eggs as a test of their toxicity. Dieldrin, 5 or 10 mg, injection into the albumin of fertile eggs prior to incubation caused decreases in hatchability of 30 and 45%, respectively. In addition, chicks from the 10-mg treatment exhibited tremors and died within 24 hours, while the chicks given 5 mg all died within 1 week of hatching. Injection of 0.2 mg of endrin into fertile eggs after 7 days of incubation decreased hatchability to 40%. Higher levels were very toxic and resulted in as low as 1.8% hatchability. Similarly, 3.0 mg of DDT per egg resulted in 10% lower hatchability. Lindane, at 2.0 mg and strobane at 6.0 mg/egg caused no decrease in hatchability. Aldrin, at 2.0 mg per egg and toxaphene and endosulfan, at 1.5 mg/egg resulted in no decrease in hatchability. The 1.5 mg injection of heptachlor resulted in 12% reduction in hatchability. All tested chicks appeared normal except those given dieldrin.

Protein Evaluation of Two Species of Cucurbita Seeds

Summary An experiment was conducted with weanling mice to evaluate the protein quality of two samples of gourd seeds (Cucurbita digitata gray and C. foetidissima HBK). These materials were compared with whole egg protein. The gourd seeds were fed after fat extraction and after autoclaving (30 min at 120°) in addition to the feeding of the untreated ground material. Amino acid analyses showed that the C. digitata seeds were deficient in phenylalanine plus tyrosine, methionine, and threonine; while, the C. foetidissima seeds were deficient in methionine and threonine. Nitrogen retention data, liver transaminase activities and amino acid retention estimates all indicated that C. foetidissima seeds were superior to C. digitata in protein quality and that C. foetidissima seeds could be improved by autoclaving but was still of lower protein quality than whole egg.

The Influence of Acetyl-Salicylic Acid on Growth and Some Respiratory Enzymes in Broiler Chicks.∗

The enzyme, succinic dehydrogenase, was observed to be significantly inhibited by salicylate in in vitro studies(l). A serum salicylate level of 137 mg/100 ml had no effect on hexokinase, cytochrome oxidase or DPNH-cytochrome c reductase(2). In vitro studies with rat liver mitochondria indicated that malate and isocitric dehydrogenase activities were inhibited by salicylate(3,4). An additional study has demonstrated that acetyl salicylic acid fed at levels of 0.005-0.08% of the diet failed to produce a significant difference in growth rate or feed conversion in 3 chick studies(5). New Hampshire X Delaware chicks were fed 0.3, 0.6 and 0.9% acetyl-salicylic acid (ASA) in addition to the basal diet (Table I). Each dietary treatment was replicated 5 times, and each replicate employed in the experiment consisted of 4 males and 4 females. All chicks were reared for 4 weeks in electrically-heated chick batteries with raised wire floors, and feed and tap water were supplied ad libitum. Feed and body weights were determined for each replicate group at the beginning and end of the experiment. At 4 weeks of age, whole blood samples, obtained by cardiac puncture, from 5 males and 5 females per treatment, were heparinized, centrifuged and frozen for analyses. The same birds were sacrificed; livers and kidneys were removed and wrapped in foil and quick-frozen. Isocitric dehydrogenase activities of the plasma were determined by the method of Wolfson and Williams-Ashman (6). Succinic dehydrogenase and cytochrome oxidase activities of the livers and kidneys were determined by the methods of Cooperstein et al(7) and Cooperstein and Lazarow(8). Enzyme activities were measured with a Beckman Model B spectrophotometer and the data recorded on a coupled Bausch and Lomb V.O. M-5 strip chart recorder. Data obtained from these tests were subjected to an analysis of variance as outlined by Snedecor(9), and differences between treatment means were tested by the multiple range test of Duncan(l0).