The effects of phytase and phytic acid on the loss of endogenous amino acids and minerals from broiler chickens

1. The effects of myo-inositol hexaphosphate (IP6) and phytase (EC 3.1.3.26) on the excretion of endogenous compounds were investigated using growing broiler chickens. 2. A total of 32 female Ross broilers were used in a precision feeding assay involving a 2 x 2 factorial arrangement of treatments. The materials administered were glucose, glucose + 1000 units of phytase activity (FTU), glucose + 1 g of IP6 and glucose + 1 g of IP6 + 1000 FTU. Excreta were collected quantitatively over a 48-h period following intubation of the test materials. The excretion of nitrogen, amino acids, minerals, sialic acid and phytate phosphorus was determined. 3. The ingestion of 1 g of IP6 by broilers increased the excretion of endogenous nitrogen, amino acids, iron, sodium, sulphur and sialic acid compared with birds fed on glucose. Supplementation of IP6 with exogenous phytase reduced the excretion of endogenous amino acids, calcium, sodium, phytate phosphorus and sialic acid compared with birds fed IP6. 4. It can be concluded that IP6 increases the excretion of endogenous minerals and amino acids in broiler chickens. Part of the beneficial effects of the addition of exogenous phytases to the diets of poultry appears to be mediated through a reduction in endogenous losses of these nutrients.     

Chemical composition and the nutritive quality of different wheat cultivars for broiler chickens

1. Different wheat cultivar samples were grown in replicated trials on a single site in three harvest years. A total of 23 wheat samples were harvested. Nutritionally complete, meal-form diets that included each wheat sample at 650 g/kg were used to compare broiler growth performance and determine apparent metabolisable energy (AME). The relationships were examined between these variables of nutritive value for broilers and the chemical composition and tests of quality on the wheat samples. 2. The total starch contents of the wheat samples ranged from 594 to 732 g/kg dry matter (DM). The mean total non-starch polysaccharide (NSP) content was 100g/kg DM comprising 73.5 g/kg DM of insoluble material. Endosperm hardness ranged between 10 and 77 relative units and Beaver was the softest cultivar in two of the batches of samples. The AME of the wheat-based diets had a maximum range of 0.5 MJ/kg within each of the three batches of wheat that were tested. 3. Endosperm hardness of the wheat grains, within a harvest year, was positively correlated with broiler weight gain and the 1000-grain weight was negatively correlated with feed conversion efficiency (FCE). Starch content and gross energy were positively correlated with determined AME, and DM, 1000-grain weight and water holding capacity were negatively correlated with AME. 4. A step-wise regression technique indicated that endosperm hardness and ash content of the wheat were the explanatory variables that, within harvest years, significantly reduced the unexplained variation in broiler growth rate, feed intake and FCE. The contents of total starch, crude protein and ether extract were the explanatory variables that, within harvest years, significantly reduced the unexplained variation in AME.     

An investigation of the toxicity of 1alpha-hydroxycholecalciferol to calves

Two calves were treated with 15 micrograms/kg body weight of 1alpha-hydroxycholecalciferol by intramuscular injection on four occasions at seven-day intervals. Anorexia and reduced water consumption persisted for 48 h after each treatment. No clinical signs of iridocyclitis or any other lesions of the eyes were present at any time either macroscopically or microscopically. After the first treatment serum GOT and GD activities increased, serum AP activity fell, serum concentrations of calcium and inorganic phosphate increased, and magnesium concentrations decreased. The reduced serum magnesium concentrations and increased calcium and inorganic phosphate concentrations were maintained for the duration of the experiment, but there was no evidence of a cumulative effect of successive treatments. Blood urea concentrations increased after the third treatment. The gross pathology at post mortem examination was similar to that reported after vitamin D3 supplementation.     

Von Baeyer/IUPAC names and abbreviated chemical names of metabolites and artifacts of aldrin (HHDN), dieldrin (HEOD) and endrin

The correct von Baeyer/IUPAC names of aldrin (HHDN), dieldrin (HEOD), and endrin, of 5 previously incorrectly-named compounds and of 18 other related compounds which have not hitherto been named in this way are presented in tabular form alongside their structural formulae. The von Baeyer ring systems present in some of these compounds were identified by inspection of Schlegel diagrams (planar representation of bridged hydrocarbons), a guide to the construction of which is presented. Also included in the tables (which have been indexed) are abbreviated chemical names; the suitability of the choices made is discussed. The alternative “polyhydroaromatic” names for 12 of these compounds have been abstracted from the literature and listed.     

Squamous cell carcinoma of the urethral process in a horse with hemospermia and self-mutilation behavior

A 14-year-old Arabian stallion was examined because of acute hemospermia. The stallion was used in an artificial breeding program and had a 6-year history of low-grade hemospermia and a 4-year history of self-mutilation behavior. During previous examinations, minor irritation of the urethral process was identified as the source of the bleeding. Physical examination revealed a mucosal ulceration in the distal portion of the urethra. Histologic examination of a biopsy specimen from this area revealed low-grade squamous cell carcinoma. The urethral process was excised, and the hemospermia resolved. Frequency of self-mutilation behaviors also decreased after surgery, suggesting that there may have been a link between irritation of the urethral process and development of self-mutilation behavior.     

The use of natural areas to establish environmental baselines

In order that wise decisions can be made in environmental management, an understanding is needed of ecosystem functioning and reaction to change. To obtain this information we must have continuing knowledge of the undisturbed ecosystem as a baseline against which to measure the effects of modifications. It is proposed that relatively undisturbed natural areas form the basic research tool for the establishment of such baselines. Thus, there is a need for a comprehensive natural area system to preserve, manage, and catalogue for use, the full range of natural area types. This, together with a network of environmental monitoring stations, should lead to the long-term continuation of the many baseline measurements required for necessary ecosystems analysis programmes. It is expected that such a system of natural area/baseline programmes will lead away from the narrow focus on pollution and towards an integrated approach to environmental quality and management.     

Effects of disk trench orientation and planting spot position on the ten-year performance of lodgepole pine

A disk-trenching experiment in thesub-boreal spruce zone of central British Columbia,Canada, established three plots (0.12 to 0.26 ha each)with trenches running east–west, and another threeplots with north–south trenches. Approximately 200Pinus contorta Dougl. seedlings were planted ineach of 13 microsites: berm, hinge, and trenchpositions in each of north, south, east, and westaspects, and in untreated locations between furrows.Soil temperature and soil moisture of representativemicrosites were monitored for 3 years; seedlingdiameter, height, and vigour were monitored annuallyfor ten growing seasons. Based on tenth-year stemvolumes, performance on south-, east-, and west-facingmicrosites was significantly greater than onnorth-facing or untreated microsites. Superior growthwas noted on all berm and hinge positions other thanthose facing north. Microsites identified as best inyear 5 were also best in year 10. On east-, south- orwest-facing berm positions, stem volume averaged 47%to 54% greater than that of control seedlings in year5, but had suffered greater mortality. Seedlings oneast-, south- or west-facing hinges were 46% to 61%(year 5), or 36% to 47% (year 10) larger thancontrol seedlings. Both east–west and north–southdisk-trenching treatments are useful for increasingseedling growth, with planting spot selection beingmore important overall than trench orientation. Thestand-level effectiveness of north–south disktrenching was greatest, because the creation of coolnorth-facing microsites was avoided.     

On the nature of a defect in cells from individuals with ataxia-telangiectasia

The cells and tissues of patients with ataxia-telangiectasia (A-T), an inherited disease characterized by a high degree of proneness to cancer, are abnormally sensitive to ionizing radiation. Noncycling cultures of normal human and A-T fibroblasts were exposed to x-rays so that the breakage and rejoining of prematurely condensed chromosomes in the G1 phase could be compared. After a dose of 6.0 grays, both cell types had the same initial frequency of breaks and the same rate for rejoining of the breaks, but the fraction of breaks that did not rejoin was five to six times greater for the A-T cells. The results also show that progression of cells into the S phase is not a prerequisite for the increased frequency of chromosome fragments that appear in mitosis after A-T cells are irradiated in the G1 or G0 phase.