Manduca sexta allatotropin and the in vitro biosynthesis of juvenile hormone by moth corpora allata: a comparison of Pseudaletia unipuncta females from two natural populations and two selected lines.

We compared the effects of Manduca sexta allatotropin (Manse-AT) on the rate of in vitro juvenile hormone (JH) biosynthesis by the corpora allata (CA) of different-aged virgin females from migrant (Quebec) and non-migrant (Azores) populations of the armyworm, Pseudaletia unipuncta, as well as from early- and late-calling lines selected from the Quebec population. There was a significant age x strain interaction, with the observed rates of JH biosynthesis in early adult life closely reflecting strain-specific differences in the age at onset of calling. In considering data for all ages combined, treatment of CA with Manse-AT resulted in a significant increase in the rate of JH biosynthesis for all but the Late strain, although significant differences for this strain were detected at certain ages. The CA of females from the Azores strain showed the strongest stimulation, with those of 0- and 1-day-old individuals displaying a singularly high degree of sensitivity. Selection for early- and late-calling lines resulted in significant differences in the temporal patterns of JH biosynthesis but did not markedly affect the sensitivity of the CA to Manse-AT. These findings are discussed within the context of the age-related differences observed in the rates of in vitro JH biosynthesis and JH haemolymph titers previously reported in comparisons of the Quebec and Azorean strains of the true armyworm.

Response of onion plants to arbuscular mycorrhizae : 2. Effects of nitrogen fertilization on biomass and bulb firmness.

The effects of N fertilization on growth and root colonization of preinoculated onion (Allium cepa L. cv. Improved Autumn Spice) were studied. Onion transplants, inoculated with either Glomus intraradices, G. versiforme or nothing at sowing, were grown under three levels of N in soils which had either been irradiated, irradiated and amended with nonmycorrhizal microflora, or not irradiated. Interactions between inoculation and soil treatment had a significant effect on dry biomass and final bulb diameter. Control plants cultivated in non-irradiated natural soil grew normally because of the presence of indigenous arbuscular mycorrhizae, but control plants in irradiated soils were stunted. There was no such difference among inoculated plants. In non-irradiated natural soil, bulbs of onions inoculated with G. intraradices or G. versiforme were significantly firmer than bulbs of control plants. Bulb firmness decreased as N fertilization level increased. In non-irradiated natural soil, tissue P concentration of onion plants preinoculated with either fungus was significantly higher than that of control plants. In all soil types, N, P, and Zn concentrations were higher in onion plants colonized by G. versiforme than in those colonized by G. intraradices. The opposite was true of Mn tissue concentration.

[Influence of bandages on the strength of impact of punches in boxing]. / Influence des bandages sur la force d'impact des coups de poing à la boxe.

In boxing, a punch can be directed to the head or the torso of the opponent; however, because of the gravity of the ensuing injuries, the limit of tolerance of the head and face to repeated impacts (Gurjian, 1955, 1962; Patrick, 1955; Hodgson and Nakamura, 1968) is particularly important to keep in mind. The objective of this research was to compare the impact forces which could be attained barehand versus those obtained with different types of bandages made up of gauze and diachylon. For the purpose of this study, 22 boxers were selected. The impact force was measured with a Kistler force plate, covered with a synthetic mattress. A system of photoelectric cells was used to measure the velocity of the punch. Each boxer had to impact the target with 10 punches while his hand was covered with one of four types of bandages as well as barehand. This study has shown that the bandaged hand increases significantly the impact force of the punch. The force increases in relation to the thickness of the bandage. The use of additional pieces of diachylon has a greater influence than gauzes. Therefore, it can be concluded that the bandaging increases the rigidity of the hand and facilitates the transfer of the force in comparison to a similar punch without a bandage or with a thinner one.

Production of Concentrated Lactococcus lactis subsp. cremoris Suspensions in Calcium Alginate Beads.

The effect of simultaneous modification of medium composition and growth conditions on the production of Lactococcus lactis subsp. cremoris biomass in calcium alginate beads was studied by the response surface method. Statistical methods of data analysis for unbalanced experiments are illustrated. The media tested were whey, whey supplemented with yeast extract and/or meat extract, milk, and the commercial medium Gold Complete (Nordica). Fermentations were performed at 23 degrees C under pH control (5.6, 6.0, 6.4, or 6.8). In one complete series, 1% CaCO(3) was added to the growth media. There were strong interactions between CaCO(3) and media, CaCO(3) and pH level, and CaCO(3), media, and pH level. In media with CaCO(3), all first-order interactions between media, pH, and sampling time were significant. The addition of CaCO(3) increased cell counts in whey-meat extract medium, but no significant difference was found with the other media. Uncoupling between growth and acidification occurred between 16 and 22 h. Highest counts were obtained on milk and Gold Complete (6 x 10/g). In CaCO(3)-containing media, pH influenced cell counts only in whey and in Gold Complete (pH 5.6 and 6.0 giving the best results); pH also influenced the bead mass obtained at the end of the fermentation. Biomass production in alginate gels is proposed as a method of obtaining concentrated cell suspensions without centrifugation or filtration.

Influence of pregnancy, lactation, litter size and diet energy density on the stomach and intestine of sows.

In the first experiment, 52 sows, each having raised one litter, were randomly assigned to the five following groups: control (nongravid) for pregnancy (CP), 110 d pregnancy (P110), control (nongravid) for lactation (CL), 4-wk lactation with 8 (L8) and with 12 (L12) piglets. In a second experiment, 36 sows, each having raised three litters, were randomly assigned to the following groups: control group (nongravid) fed a low-energy-density, 1% tallow diet (CLED) and two lactating groups, one fed the low-energy-density diet (LLED) and one fed a high-energy-density, 10% tallow diet (LHED). At slaughter, the stomach, small and large intestine and cecum were excised, emptied and freed from fat. Lengths and pre- and post-defatting weights were measured. Portions of tissues were homogenized and analyzed for protein, pepsin, maltase, RNA and DNA. Pregnancy had no effect on the weights of the different components of the gastrointestinal tract. Liver and small intestine weights were larger in lactating sows than in the CL group. Sows nursing 12 piglets had heavier livers than those nursing 8. The fundic mucosa of the latter had higher total pepsin activity and total protein and RNA contents than that of L12 sows. LHED sows had heavier small intestine and lower total pepsin content of the fundic mucosa than LLED sows.

Transgene integration patterns and expression levels in transgenic tissue lines of Picea mariana, P glauca and P abies.

Seventy transgenic tissue lines (translines) of three spruce species ( Picea mariana, P. glauca and P. abies) were characterized with respect to the integration pattern of the gus (beta-glucuronidase) gene, and the level of GUS activity was determined in 81 lines. The majority of the P. mariana translines (18 lines of 22) integrated multicopies of the transgene, whereas mostly single integrations were detected in the other two species. The activity levels of GUS varied widely among the individual translines of P. mariana, and there was a strong indication that the logarithm of GUS activity increased with the number of gus copies ( P=0.0003) in lines with one to five known insertions (uncensored). The average level of GUS activity, in lines that integrated one gene copy, was the highest in white spruce followed by black spruce and Norway spruce (22.7, 16.5 and 6.3 nmol 4-methylumbelliferone min(-1 )mg(-1 )protein, respectively).

Injection of synthetic human growth hormone-releasing factors in dairy cows. 1. Effect on feed intake and milk yield and composition.

Eighteen multiparous Holstein cows in the second half of their lactation were used to determine the effect of human growth hormone-releasing factor (1-44)NH2 and a fragment of growth hormone-releasing factor (1-29)NH2 on lactational performance and feed intake. Saline, the 44-amino acid peptide or the 29-amino acid fragment, at the same dose per injection (.2 nmol.kg-1) was injected intravenously at 4-h intervals for 10 d. Average milk yield, milk composition, feed intake, and feed efficiency were compared for the second half of each 10-d preinjection, injection, and post-injection period. Injections of the 44-amino acid peptide and the 29-amino acid fragment increased milk yield 18.6 and 14.6%, respectively. Feed intake was not changed, but feed efficiency was increased 23.9 and 18.8% over control following 44-amino acid peptide and the 29-amino acid fragment injection, respectively. The lactational response was not different between the two peptides for any of the variables measured. This study demonstrates the feasibility of using a growth hormone-releasing factor fragment as an alternative method of elevating milk yield in cattle via somatotropins.