Expression of the trophoblast interferon, bovine trophoblast protein-1 (bTP-1), has been studied in embryos produced by in vitro maturation-in vitro fertilization (IVM-IVF). No bTP-1 production was noted until after embryos had reached the expanded blastocyst stage and had begun to hatch (Days 8-9 post-fertilization). Single blastocysts comprising 115 +/- 22 cells released 1.0 +/- 0.1 units of interferon activity/24 h. Amplification of conceptus mRNA by reverse transcription-polymerase chain reaction procedure with bTP-1-specific oligonucleotides confirmed that bTP-1 transcripts were present in blastocysts but were not detectable at earlier stages. Although cultured blastocysts produced by IVM-IVF procedures continued to secrete bTP-1 for a few days, they failed to attach to the substratum and form outgrowths, and soon lost structural integrity. However, when Day 8 blastocysts/morulae were transferred to the uteri of synchronized cows, recovered 4 days later, and placed into individual cultures, they attached and formed outgrowths that produced large amounts of bTP-1 (greater than 2000 units/culture/24 h after 14 days). Embryos thus first expressed bTP-1 when a functional trophectoderm was first formed, and induction did not require a period of in vivo development. However, continued viability of the blastocyst and bTP-1 production were not sustained in vitro and may require some exposure to the uterine environment.

Bovine embryos, whether produced naturally or by in vitro techniques, exhibit considerable variability in morphological quality and develop at different rates. Our objectives have been to determine whether initial expression of trophoblast interferon (IFN-tau) was a reflection of conceptus stage of development or age and whether there was an effect of embryo quality on the amount of IFN-tau produced. Early blastocysts (N = 187) were selected at the onset of blastocoele formation and cultured individually. Embryo quality (excellent, good, or fair: E, G, or F) and developmental stage (early, expanded and hatched blastocysts: BL, EBL, and HBL, respectively) were used in a 3 x 3 factorial complete randomized block design, each block (n = 4) consisting of batches of embryos produced from oocytes in different collections. Quality and developmental stage of embryos and IFN-tau released into the medium were assessed every 24 h. Production of IFN-tau (units/embryo/24 h) was greater (P < 0.01) among hatched blastocysts (HBL; 0.91 +/- 0.08) than expanded blastocysts (EBL; 0.23 +/- 0.04) and early blastocysts (BL; 0.05 +/- 0.08). Embryos of similar developmental stage but differing by 2 days in age released equal amounts of IFN-tau. Expression of antiviral activity increased (P < 0.05) from 27% to 57% to 100% as development proceeded from BL to EBL and to HBL respectively. More IFN-tau was produced by HBL graded G (1.0 +/- 0.1) or E (1.3 +/- 0.1) than by those of F quality (0.5 +/- 0.1). All blastocysts, whatever their quality and developmental stage, contained IFN-tau mRNA.(ABSTRACT TRUNCATED AT 250 WORDS)

Oviducal fluid is important in the reproductive process because of its key function in relation to fertilization and early development of the embryo. Hafez & Blandau (1969)

Five major phospholipids of ejaculated and epididymal porcine spermatozoa were separated and quantitatively determined by thin-layer chromatography. These were in the order of decreasing concentration, phosphatidyl choline, phosphatidyl ethanolamine, ethanolamine plasmalogen, sphingomyelin and choline plasmalogen. Phosphatidyl serine, lysolecithin and possibly phosphatidyl inositol were also present, but in low concentrations. The concentration of phosphatidyl choline and phosphatidyl ethanolamine in spermatozoa progressively decreased from the head to the tail of the epididymis, and was lowest in ejaculated semen. The plasmalogen content of spermatozoa from all levels of the reproductive tract of the boar was low and varied very slightly.

Automated solutions for fresh market fruit and vegetable harvesting have been studied by numerous researchers around the world during the past several decades. However, very few developments have been adopted and put into practice. The reasons for this lack of success are due to technical, economic, horticultural, and producer acceptance issues. The solutions to agricultural robotic mechanization problems are multidisciplinary in nature. Although there have been significant technology advances during the past decade, many scientific challenges remain. Viable solutions will require engineers and horticultural scientists who understand crop-specific biological systems and production practices, as well as the machinery, robotics, and controls issues associated with the automated production systems. Focused multidisciplinary teams are needed to address the full range of commodity-specific technical issues involved. Although there will be common technology components, such as machine vision, robotic manipula-tion, vehicle guidance, and so on, each application will be specialized, due to the unique nature of the biological system. Collaboration and technology sharing between commodity groups offers the benefit of leveraged research and development dollars and reduced overall development time for multiple commodities. This paper presents an overview of the major horticultural and engineering aspects of robotic mechanization for horticultural crop harvesting systems.