Effect of transport loading or noise on blood biochemical variables in calves

The influence of 2 transport stressors (loading and noise) on several serum and plasma biochemical variables was studied in 4 calves. When calves were loaded and kept for 30 minutes on a motionless transport simulator or were exposed to the noise of the working simulator, increases in plasma epinephrine and serum cortisol and nonesterified fatty acids concentrations were similar to changes observed in calves subjected to simulated transport for 30 minutes. Results indicate that loading and noise have an important role in transport stress.     

The effect of nerve growth factor on nuclear progression of porcine oocytes during in vitro maturation and embryo development

The present study examined the effect of nerve growth factor (NGF) on in vitro maturation (IVM), in vitro fertilisation (IVF) and subsequent embryonic development of porcine oocytes. Cumulus-oocyte complexes were cultured with or without 1.0 ng/ml NGF for 40 h. After IVF, they were cultured in vitro for 6 days. After 10 and 20 h of IVM, there was no difference in nuclear status between the NGF-treated and control oocytes. Significant differences were detected in nuclear progression of oocytes matured in the presence or absence of NGF at 30 h of culture. A higher proportion of NGF-treated oocytes were at M-II stage compared to the control. Nevertheless, at the end of the 40-h IVM period, there was no difference in the proportion of M-II stage oocytes between the NGF-treated and control groups. NGF in IVM medium did not influence the developmental competence of putative embryos. Most embryos remained at the 2- to 4-cell stage; however, a significant amount of embryos reached the morula stage both in the NGF and the control groups. These results suggest that NGF during IVM accelerates nuclear progression of porcine oocytes by enhancing the post-diakinetic events of meiosis.     

Hatchery hygiene evaluation as measured by microbiological examination of samples of fluff

The microbial content of 1,180 samples of fluff from hatchers at 18 chick and 6 turkey hatcheries has been determined. The samples were taken (a) 12–15 hr before removal of birds from the hatchers, (b) just before or after theremoval of chicks orpoults, (c) after fumigation and (d) inreplicate from the same hatcher.

Fifty‐eight per cent of the samples of chick fluff contained one million or more bacteria but only 24 per cent contained more than 100,000 coli‐aerogenes bacteria. Moulds were not found in 68 per cent of the samples. Some samples of fluff were examined for coagulase positive staphylococci and fluorescent pseudomonads but these organisms were generally not detected. Bacillus cereus was recovered in very large numbers from a few samples. Bacterial and coli‐aerogenes counts from poult fluff were generally higher than those from chick fluff but the numbers of pseudomonads and coagulase positive staphylococci recovered were generally negligible.

In an intensive study of samples of fluff from one turkey hatchery, it was found that the level of contamination of fluff increased during hatching and the laying season and was accompanied by a decrease in poult quality. Sampling from any location in the hatcher appears to provide a representative indication of overall contamination at that time. Fumigation of fluff and debris generally caused a reduction in the level of contamination in the fluff.

A suggested assessment of hatchery hygiene based on the microbial examination of fluff is given and the advantages and disadvantages of this method are discussed.     

Aminomethylphosphonic acid, a metabolite of glyphosate, causes injury in glyphosate-treated, glyphosate-resistant soybean

Glyphosate-resistant (GR) soybean [Glycine max (L.) Merr.] was developed by stable integration of a foreign gene that codes insensitive enzyme 5-enolpyruvylshikimate-3-phosphate synthase, an enzyme in the shikimate pathway, the target pathway of glyphosate. Application of glyphosate to GR soybean results in injury under certain conditions. It was hypothesized that if GR soybean is completely resistant to the glyphosate, injury could be caused by a metabolite of glyphosate, aminomethylphosphonic acid (AMPA), a known phytotoxin. Glyphosate and AMPA effects on one- to two-trifoliolate leaf stage (16-18-days old) GR and non-GR soybean were examined in the greenhouse. In GR soybean, a single application of glyphosate-isopropylammonium (1.12-13.44 kg/ha) with 0.5% Tween 20 did not significantly reduce the chlorophyll content of the second trifoliolate leaf at 7 days after treatment (DAT) or the shoot dry weight at 14 DAT compared with Tween 20 alone. A single application of AMPA (0.12-8.0 kg/ha) with 0.5% Tween 20 reduced the chlorophyll content of the second trifoliolate leaf by 0-52% at 4 DAT and reduced shoot fresh weight by 0-42% at 14 DAT in both GR and non-GR soybeans compared with Tween 20 alone. AMPA at 0.12 and 0.50 kg/ha produced injury in GR and non-GR soybean, respectively, similar to that caused by glyphosate-isopropylammonium at 13.44 kg/ha in GR soybean. AMPA levels found in AMPA-treated soybean of both types and in glyphosate-treated GR soybean correlated similarly with phytotoxicity. These results suggest that soybean injury to GR soybean from glyphosate is due to AMPA formed from glyphosate degradation.     

Temperature effects on xylem sap osmolarity in walnut trees: evidence for a vitalistic model of winter embolism repair

We studied the effect of temperature on the carbohydrate status of parenchyma cells during winter in relation to the efflux and influx of sugars between parenchyma cells and xylem vessels in 1-year-old twigs of walnut (Juglans regia L.). The mechanism of sugar transfer between contact cells and vessels was also investigated. We obtained new insights into the possible osmotic role of sugars, particularly sucrose, in stem pressure formation and winter embolism repair. Accumulation of sucrose in the xylem sap during winter was mainly influenced by: (1) abundant conversion of starch to sucrose in the symplast at low temperatures; (2) sucrose efflux into the apoplast at low temperatures (1 degrees C); and (3) inefficient sugar uptake at low temperatures, although efficient sugar uptake occurred at 15 degrees C. We hypothesize that a diethyl pyrocarbonate (DEPC)-sensitive protein mediates facilitated diffusion of sucrose from parenchyma cells to xylem vessels (efflux) in walnut. We discuss the possible occurrence of active H+-sucrose symports and the coexistence of both influx and efflux processes in walnut in winter and the modulation of the relative importance of these flows by temperature.     

Amino acid composition,relative nutritive value and in vitro protein digestibility of several Philippine indigenous legumes

This study demonstrates variability in amino acid composition among accessions of several Philippine indigenous legumes. Moreover, two accessions ofD. lablab were identified to have high level of methionine (>2%). Methionine was identified as the first limiting amino acid with leucine, and threonine as the second limiting amino acids for most legumes studies.The IVPDs of the legumes under study ranged from >70 to 79%. Raw mature seeds had relatively low RNVs of 11 to 68% which increased to 68 to 94% and 51 to 89% after boiling and roasting, respectively.