Parasite life-history traits reflect past environmental and host selective pressure that act to produce strategies that maximize successful transmission. Pooled human pinworm eggs were pretreated with 0.9% NaCl, acid digestive enzyme, and alkaline solutions (pH 9.0) and then incubated in 0.9% NaCl at room temperature and 37 degrees C both with and without 5% CO2. Eggs pretreated with both acid ...

A study was conducted to investigate Fe requirements of broiler breeders. One-hundred-fifty-six Cobb 500 broiler breeder hens were individually placed in electrostatically painted cages at 22 weeks. The study was composed of an adaptation phase, in which hens were fed corn-soy-wheat bran diets until 35 wks. An Fe deficient mash diet (24.6 ppm Fe) was provided from 35 to 46 wk in order to induce...

It is generally accepted that the hatching of mouse blastocysts is accompanied by regional dissolution of the zona pellucida by a trypsin-like proteinase synthesized in trophectoderm cells (Perona and Wassarman, 1986; Hogan et al., 1994), and trophectoderm cells protrude from the dissolved hole of the zona pellucida (Orsini and McLaren, 1967; McLaren, 1970; Niimura and Fujii, 1997). Then a slit...

The emergence of the mammalian blastocysts from their thick glycoprotein investment known as the zona pellucida is an important, but poorly understood, event in embryogenesis. In this paper, we demonstrate that peri-hatching blastocysts generate a considerably high quantum of an active oxyradical species for an extremely short period of time when compared to the pre-hatching (unhatched) and pos...

Globodera rostochiensis and G. pallida responded similarly to hatch stimulation by potato root leachate, but proportionally more second-stage juveniles (J2s) of G. rostochiensis hatched than of G. pallida in response to picrolonic acid, sodium thiocyanate, alpha-solanine, and alpha-chaconine. Fractionation of the potato root leachate identified hatching factors with species-selective (active to...

We present a method for drawing lines on an object that depict both the shape and shading of the object. To do so, we construct a gradient field of the diffuse intensity of the surface to guide a set of adaptively spaced lines. The shape of these lines reflect the lighting under which the object is being viewed and its shape. When the light source is placed at the viewer’s location, these lines...

A growing body of work suggests that the activity of ion channels and pumps is an important regulatory factor in embryonic development. We are beginning to identify functional roles for proteins suggested by a survey of expression of ion channel and pump genes in Xenopus and chick embryos (Rutenberg et al. [2002] Dev Dyn 225, this issue). Here, we report that the ATP-sensitive K channel protein...

In temperate regions, the seasonal dynamics of Aedes aegypti (L.) (Diptera: Culicidae) is mainly influenced by temperature. It is assumed that, during the winter season, the population remains as eggs and that the development and population growth of surviving eggs begin during the following spring. The aim of the current study was to assess the temporal dynamics of egg hatching of Ae. aegypti ...