Tadpole Antibodies against Frog Hemoglobin and Their Effect on Development

Rana catesbeiana tadpoles immunized with the main hemoglobin component of the adult frog of the same species produced precipitating and agglutinating antibodies against the immunogen. After natural metamorphosis, the immunized froglets have as their only major hemoglobin a protein immunologically and electrophoretically different from the major hemoglobin of control froglets.     

Immunity in foot-rot infection

Extract

Infestation with Fasciola hepatica is an important cause of disease and economic loss in domestic animals in many parts of the world. Among the effects attributed to fluke infestation are loss of condition, reduced meat and milk production, reduced fertility, and rendering of livers unsuitable for human consumption. Severe infestation may cause death either directly or indirectly by initiating or aggravating bacterial infection, as in the case of black disease.     

Studies of the Pink Bollworm,Pectinophora gossypiella,on Sea Island Cotton in Barbados

Abstract

Barbados once grew large amounts of Sea Island cotton but the accidental introduction of pink bollworm (Pectinophora gossypiella) in the 1920s, falling prices and rising costs led to the collapse of the industry. Falling sugar prices subsequently led to a revival of interest in the crop but pink bollworm still presented a problem and warranted investigation.

The synthetic sex pheromone of pink bollworm, gossyplure, was shown to attract far more males than hexalure or virgin females. Sticky traps needed stirring daily and were only able to catch about 50 males a night. Water, with a drop of liquid detergent, proved to be a suitable trapping medium and was cheaper than liquid paraffin although not quite as effective. The best type of trap from materials readily available was one made from a plastic half gallon ice cream container with lid and holes cut around the upper sides. Traps without the attractant caught very few moths. Gossyplure adsorbed onto rubber caps was attractive to pink bollworm males for over 56 days but the half-life appeared to be about 28 days. Best catches were obtained in cotton when the traps were suspended just below the tops of the plants and, within fields, traps at the leeward end caught more than traps elsewhere. Peak catches of males occurred before midnight in a black light trap whereas pheromone traps caught no males before midnight but peaked at 03.00h.

A close season during which no cotton is allowed to grow is a recognised means of reducing pink bollworm carryover between crops. This was practised in Barbados but island-wide pheromone trapping showed that moths were caught throughout the close season. This continuous trapping of moths indicated that pink bollworm must be breeding (short-cycle) in order to survive. Trapping and laboratory studies confirmed the presence of long-cycle pink bollworm which entered diapause towards the end of the cotton season as daylength increased. This diapause terminated with shortening days after the new season's rains commenced. The case for a four month close season is discussed.

Pheromone trap catches were shown to be very closely correlated with boll damage. Catches of 8–9 moths in a night represented a 10% level of boll damage some ten days later and this is the trapping level at which cotton growers are advised to begin insecticidal treatment.

Thorough residue destruction is the key to a good close season and a suitable method was needed for use under Barbadian conditions. The method finally chosen and proved on an estate scale was to cut down the standing cotton with a horizontal-rotary chain slasher, driving across the rows of cotton, the debris was then raked along the rows, stacked and burnt and finally the stumps were ploughed in, again across the rows.

The parasite Perisierola nigrifemur is very common in pink bollworm larvae towards the end of the season but too late to be of economic value. Predation of diapausing larvae by the mite Pyemotes ventricosus is very common at the end of the cotton crop and during the close season. Insecticidal application in Sea Island cotton which usually grows very tall (> 1.75m) and rank is best achieved with hand-held, battery-operated, u.l.v. sprayers. Control of pink bollworm can be obtained with carbaryl S formulations applied through these sprayers with the addition of a little water and molasses. Synthetic pyrethroids in u.l.v. formulations are also expected to provide control.     

Spatial variability of phenology in two irrigated grapevine cultivar growing under semi-arid conditions

Knowledge and monitoring of the grapevine phenology during the season are important requirements for characterization of productive regions, climate change studies and planning of various production activities at the vine field scale. This work aims at studying the spatial variability of grapevine phenology at the within field scale. It was conducted on two fields, one of cv Cabernet Sauvignon of 1.56 ha and the other of cv Chardonnay of 1.66 ha, both located in Maule Valley, Chile. Within each vine field, a regular sampling grid was designed, to carry out weekly measurements of phenology and maturation. The main results show that there is a significant spatial variability in the phenological development and maturation at the within field scale for both fields. This variability is spatially organised and temporally stable from the beginning of the season (post-budburst) to harvest and over the years. A cluster analysis allowed us to define two clearly contrasted zones in terms of phenology and maturation in both fields, explained by the microclimate. The magnitude of difference between zones varied from 4 to 9 days depending on phenological stages and from 5 to 43 days for maturation. These differences are similar and comparable to that observed at larger scales or under scenarios of climate change. These results highlight the necessity to better take into account this variability to improve sampling and to base decisions of production activities (spraying, harvest, pruning, etc.) application on more relevant information. Further investigations should determine the environmental factors that determine the observed spatial variability.     

Effect of Roscovitine‐Treated Donor Cells on Development of Porcine Cloned Embryos

Synchronization of the donor cell cycle is an important factor for successful animal cloning by nuclear transfer. To improve the efficiency of porcine cloning, in the present report, we evaluated effects of contact inhibition, serum starvation and roscovitine treatment of donor cells on in vitro and in vivo developmental potency of cloned porcine embryos. Fibroblasts derived from a porcine foetus at day 30 of gestation were isolated and cultured to 70% confluency. Then, cells were either cultured to 100% confluency for contact inhibition, or cultured in 0.5% serum for 72 h for serum starvation or with 15 μm roscovitine for 24 h. Cells were most effectively synchronized at G0/G1 in the serum starvation group (87.5%) compared with the contact inhibition and roscovitine treatment groups (76.3% and 79.9% respectively p < 0.05). However, after somatic cell nuclear transfer followed by in vitro culture, the serum starvation group showed a significantly lower blastocyst formation rate (5.6%) compared with the contact inhibition and roscovitine treatment groups (11.6% and 20.0% respectively). Differential expression of apoptosis‐related genes and the level of apoptosis in each treatment group explain the variation in developmental competence among the groups. Significantly higher level of apoptosis was observed in the serum starvation group. On the other hand, the roscovitine treatment group shows the lowest level of apoptosis and the best in vitro development among the groups. Cloned embryos derived from roscovitine‐treated donor cells were transferred to surrogate pigs. Three healthy live piglets were produced. In conclusion, we suggest that roscovitine treatment of donor cells improves development of cloned porcine embryos and can raise the efficiency of cloned piglet production.     

Rare frogs and reptiles of Cape York Peninsula,Australia

‘Rare’ frogs and reptiles on Cape York Peninsula are those which are not found elsewhere in Australia, and which are known from either 20 or fewer museum records or from five or less localities. The six rare frog species and 22 rare reptile species are listed. Detailed data on their habitat requirements, distribution, and preservation through habitat protection in reserves are presented. Seven species inhabit areas which are not protected in any National Parks, State Forests, or Timber Reserves.