New routes to early memories

Stimulation of one side of the olfactory system during training with odor-milk pairings in neonatal rats results in their ability to recall an odor memory by using the trained but not the untrained side of the brain. In 12-day-old rats, olfactory learning can be recalled by stimulation of either the trained or untrained side. The development of bilateral recall reflects the maturation of olfactory commissural pathways that provide access to the olfactory memory stored on the contralateral side. Furthermore, the commissural pathways need not be present at the time of memory formation but can establish new and specific access to already existing olfactory memories.     

Serologic correlation of suspected Leptospira interrogans serovar pomona-induced uveitis in a group of horses

After the observation of 2 horses with uveitis on a horse farm in the Minnesota River valley, 100 horses from this geographic area were given ophthalmologic examinations and were evaluated serologically for leptospirosis. A statistically significant (P less than 0.001) association was observed between the finding of antibodies against Leptospira interrogans serovar pomona and uveitis.     

Recording of the reticular motility in cattle with experimental and spontaneous traumatic reticuloperitonitis

Using the method described in a previous publication for recording the reticulum action in normal cows the authors have investigated three cows with experimentally produced reticuloperitonitis as well as a group of cows with spontaneous peritonitis under treatment at the stationary clinic. The experimental animals were provided with permanent rumen fistulas.In the three cows with experimentally produced peritonitis the pointed object worked loose spontaneously during the first 24 hrs. The symptoms were mild after the first perforation and became aggravated after further perforations.An abnormally prolonged reticulum interval was recorded immediately after the perforation and continued to be clearly distinguishable for two to three days. In the cows with spontaneous peritonitis, this change was observed only in the acute stage.Prolongation of the second phase of the reticulum was the most pronounced finding from the recordings of the reticular movements, both in the cows with experimental peritonitis and in those in the spontaneous group. The change was at its height after two to seven days, and then subsided gradually in the experimental animals in which repeated recordings had been made.The pressure elevation in reticulum during the contractions was lower both in the animals with experimental peritonitis and in the spontaneous group than in the healthy animals.The cows with reticuloperitonitis also displayed impaired ability to pass the recording catheter from the atrium ruminis to the reticulum.     

Influence of Phytohemagglutinin on the Agronomic Performance of Beans (Phaseolus vulgaris L.)

The abundant lectin phytohemagglutinin (10 % of total seed protein) does not contain sulfur amino acids and, being a potent antimetabolite, it is responsible for the lowering of the nutritional value of bean seeds. The aim of the present work was to improve the dry bean cultivar ‘Taylor's Horticultural’ (Asgrow), by genetically introducing the lectin null (lec/lec) character from two null genotypes: ‘Pinto UI 111’ and ‘Heidi’. Thirty-seven BC²F₃ and fourteen BC₆F₅ inbred lines were evaluated in agronomical trials. Analysis of Variance (ANOVA) showed significant differences among BC₂F₃ breedings lines for all traits under evaluation. Comparison of the LedLee genotypes versus lec/lec did not show statistically significant differences in the means for the following traits: yield, yield components and percentage of protein in the seed. Fourteen BC6F5 lines, compared together with their recurrent parent ‘Taylor's Horticultural’, showed significant differences among genotypes for 1000 seed weight, protein percentage on dry matter and ash percentage. No significant differences were observed for grain yield. The data indicate that lectin removal did not have a detrimental effect on the traits evaluated.     

Measured Soil Water Concentrations of Cadmium and Zinc in Plant Pots and Estimated Leaching Outflows from Contaminated Soils

Soil water concentrations of cadmium and zinc were measured in plant pots with 15 contaminated soils which differed in origin, texture, pH (5.1 – 7.8) and concentrations of cadmium (0.2 – 17 mg Cd kg-¹) and zinc (36 – 1300 mg Zn kg-¹). The soil waters contained total concentrations of 0.5 to 17 µg Cd L-¹ and 9 to 3600 µg Zn L-¹, which were dominated by free metal ions as measured by an ion exchange-resin method. Annual leaching outflows were estimated from soil water concentrations to be 0.5 – 17 g Cd ha-¹ y-¹ and 9 – 3600 g Zn ha-¹ y-¹ per 100 mm of net percolation, corresponding to 0.1% per year of the total soil content of cadmium and zinc. The measured soil water concentrations of cadmium and zinc did not correlate linearly with the corresponding soil concentrations but correlated fairly well with concentrations measured in Ca(NO₃)₂ extracts of the soils and with soil water concentrations estimated from soil concentrations and pH. Such concentration estimates may be useful for estimating amounts of cadmium and zinc being leached from soils.     

A holistic view of poultry science from a reductionist perspective

1. The success of the poultry industry has been dependent upon development of a precise understanding of poultry biology. 2. The advent of tools and probes that reveal the molecular and cellular organisation of complex physiological systems should be embraced by the poultry industry to gain insights into recurring problems such as egg shell quality and ascites. 3. The ability to modify the genome of chickens provides an opportunity to breed chickens with unprecedented precision. 4. The judicious use of time and resources will require a working knowledge of molecular and cellular biology and the poultry industry. There is an urgent need for educational facilities that provide both perspectives.