Litter Size and Vagina–cervix Catheter Penetration Length in Gilts

As in other species, the reproductive tract in pigs increases in size with age and body weight, and the development of the reproductive tract depends on a balance between development of the pituitary–ovarian axis and the influence of metabolic hormones. Two experiments were conducted in prepubertal Duroc gilts, 150–180 days of age, to determine whether litter size is related to vaginal–cervix catheter penetration length during insemination. In experiment 1, oestrus was induced in 452 gilts with a combined dose of 400 IU Pregnant Mare Serum Gonadotrophine (PMSG) + 200 IU human chorionic gonadotropin (hCG). The gilts were classified into three catheter penetration length groups: Ih, ≤ 21 cm; IIh, > 21 and < 28 cm; IIIh, > 28 cm. The litter size was lowest in group Ih (7.35 ± 0.15) compared with groups IIh (7.81 ± 0.12; p < 0.05) and IIIh (10.0 ± 0.36; p < 0.001). In experiment 2, first oestrus was induced in 162 gilts by boar exposure. The gilts were classified into three catheter penetration length groups at insemination during their second oestrus: In, ≤ 24 cm; IIn, > 24 and < 26 cm; IIIn, > 26 cm. As in experiment 1, the litter size was lowest in the group with the shortest catheter penetration length (8.32 ± 0.19). The litter size was not different among gilts of groups IIn and IIIn (8.84 ± 0.35 and 9.56 ± 0.46, respectively), but litter size was lower (p < 0.05) in group In than in group IIn. Based on the combined data from both experiments, the correlation between the catheter penetration length and total number of piglets born was expressed as: y=5.346 ± 0.104x; r=0.361 (p < 0.05). Fertility rate was not different among the groups of gilts induced into oestrus by hormone treatment or inseminated in the second oestrus; however, the total fertility rate of boar‐exposed gilts was higher (p < 0.0001) than PMSG/hCG treated animals. Thus, it is possible to conclude that litter size at first farrowing is associated with vaginal–cervix catheter penetration length during insemination of the gilt.     

Serological tests in relation to the viability,fertility and localization of hydatid cysts in cattle,sheep, goats and swine

A serological study of intermediate hosts (cattle, sheep, goats and swine) of Echinococcus granulosus was carried out by means of the indirect haemaglutination (IHA) and flocculation with latex (LA) tests, relating them with the organs invaded, and the fertility and viability of the cysts.In cattle a sensitivity of 75% and 21.05% of non-specific reactions was given by IHA, while the LA gave 66.7 and 17.54%, respectively. In the sheep, the IHA gave 79.16 and 20%, and the LA, 75 and 15%. In the goat, the IHA gave 76 and 22%, and the LA 71.43 and 16%. Finally, in the pig, the IHA gave 75 and 22%, and the LA, 66.6 and 14.16%.The IHA was more sensitive in detecting hepatic cysts in the cow, and pulmonary cysts in the goat, while in the sheep and the pig there were no significant differences. The LA was more sensitive in detecting hepatic cysts in the cow, goat and pig, while there were no significant differences in sheep.The differences in serum titers by the IHA and the LA tests with respect to the viability and the fertility of the cysts in the hosts, were not significant.     

Seed production of Charybdis feriatus (Linnaeus)

Some aspects of the reproductive biology of Charybdis feriatus (Linnaeus) were investigated to identify suitable techniques for broodstock management and seed production. Likewise, factors such as ablation, water depth and light requirements affecting survival or reproductive performance were tested. Production of megalops in tanks and juveniles in net cages installed in earthen ponds was conducted. Wild‐caught berried females produced a significantly higher number of zoeae per gram body weight (BW) of the female (3300±600) than captive spawners (867±58). Ablated and unablated crabs spawned after a month and ovaries of both had oocytes in all developmental stages after spawning, indicating that ablation was not necessary. Broodstock survived higher when stocked in 1 m‐deep water and kept in dark conditions compared with shallow (0.5 m depth) water or ambient lighting. There were six zoea and one megalopa stage. Megalops were produced (survival of 2–22% in 1 tonne or 23–55% in 3 L tanks) when methods for the mud crab Scylla serrata (Forsskål) were used, but feeding with Artemia started only at the Z4 stage. Survival of megalops after 1 month was higher when stocked in net cages installed in an earthen pond (32–82%) than when reared continuously in land‐based tanks (5–11%).     

Efficacy of repeated doses of levamisole, morantel, fenbendazole, and ivermectin against gastrointestinal nematodes in ewes

Levamisole, morantel, fenbendazole, or ivermectin was administered at 2-week intervals from May 1 through Sept 14, 1985, to breeding ewes (20 ewes/drug) infected with various gastrointestinal nematodes. All ewes had fewer gastrointestinal nematode eggs per gram of feces (epg) after 2 treatments, compared with pretreatment epg counts. Ewes administered ivermectin continued to have a low mean epg (0 to 3) throughout the study. The mean epg counts of ewes treated with levamisole increased from 3 to 483 during the study. This increase was similar to that of ewes treated with morantel (7 to 485 epg). The mean epg count of fenbendazole-treated ewes increased from 4 to 192 during the study. By the end of the study, the mean epg counts when expressed as a percentage of the pretreatment epg counts were 4% (ivermectin), 249% (fenbendazole), 627% (levamisole), and 630% (morantel). With the exception of the ivermectin-treated ewes, the epg count increased almost linearly in the ewes after the 2nd anthelmintic treatment. These data indicate that the gastrointestinal nematodes (including Haemonchus contortus) may have developed more resistance to levamisole and morantel than to fenbendazole. On the basis of the epg counts, resistance to ivermectin did not develop during the 4.5-month treatment period. The percentage of ewes shedding eggs after 2, 4, and 6 anthelmintic treatments was lowest for ewes treated with ivermectin (20%) and was similar (40%) for ewes treated with 1 of the other 3 anthelmintics. At the conclusion of the study, most of the ewes (90%) were shedding at least a small number of eggs, regardless of the anthelmintic treatment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evaluation of a cloned Babesia bovis organism as a live immunogen

A Babesia bovis isolate was cloned by in vitro cultivation and compared to the original cultured isolate for pathogenicity by animal inoculation. Four yearling heifers were inoculated with cloned material and 4 with the original culture. The four animals which received the cloned Babesia showed comparatively minor hematologic changes and no clinical signs. One animal died in the group that received uncloned Babesia and the mean temperature increase and mean reduction in packed cell volume (PCV) was greater in that group. The four animals receiving the cloned material were challenged 100 days following initial inoculation. All of the animals were totally immune with no significant change in temperature or decrease in PCV, whereas control (previously non-inoculated) animals developed significant (P less than 0.001) increases in temperature and severe anemia. The cloned organism appears to be a candidate live immunogen for use in endemic areas to induce protection against bovine babesiosis.     

Evaluation,tissue culture propagation,and dissemination of ‘Saba’ and ‘Pelipita’ plantains in Costa Rica

Fruit characteristics of the disease-resistant bluggoe-type (ABB) cooking bananas (Musa × paradisiaca L.) ‘Saba’ and ‘Pelipita’ were compared with those of the susceptible ‘Currare’ (‘Horn’). Yields of ‘Saba’ and ‘Pelipita’ were similar to those of ‘Currare’; however, ‘Saba’ and ‘Pelipita’ yielded fewer hands with a greater number of small fruit when compared with ‘Currare’. Shoot-tip cultures of both clones were readily initiated on a modified Murashige and Skoog (MS) basal medium supplemented with N⁶-benzyladenine (BA) in combination with indole-3-acetic acid (IAA). Propagation cultures were initiated by splitting shoot tips along their longitudinal axis and re-culturing the individual pieces to basal medium supplemented with 5 mg l^?1 BA. Transfer of axillary shoots to hormone-free medium resulted in rapid and extensive root formation. Plantlet survival after transfer to methyl bromide-treated soil exceeded 90%. Establishment in the field was achieved following procedures normally used for vegetative propagation of this crop. Trial plantings of in vitro propagated ‘Saba’ and ‘Pelipita’ were established in various provinces of Costa Rica for grower evaluation and for future comparison of growth and reproductive development with plants of these and other cultivars propagated from corms.     

Differential expression of genes encoding cell wall proteins in vascular tissues from vertical and bent loblolly pine trees

Differential expression of cell wall proteins during plant development and in response to biotic or abiotic stress suggests that these proteins may contribute in different ways to plant cell wall architecture. Because the wood of loblolly pine (Pinus taeda L.) is highly specialized in the formation of secondary cell walls, it is an ideal tissue for studying these proteins. The cDNAs coding for six novel cell wall associated proteins, as well as a homologue for a phytocyanin, were identified and characterized from differentiating xylem of loblolly pine. Three of these cDNAs encoded new putative loblolly pine arabinogalactan proteins, based on their structural similarity to classical arabinogalactan proteins (AGPs). In addition, one clone was related to the proline-rich protein group and the other two to the glycine-rich protein group and the mussel adhesive protein. Relative expression of these genes was examined in different tissues and organs from normal trees (needles, phloem and vertical wood), the underside of bent trees (compression wood) and the lateral sides of the bent stems (side wood). All clones, except one, were highly expressed in vascular tissues with noticeable differences among the three types of wood. Their relationships and diversity provide the first insights into concerted expression and related function for this important group of proteins in cell wall formation of wood.     

Stem modeling and simulation of conversion of cork oak stems for quality wood products

Recent research is underway to study cork oak (Quercus suber L.) wood potential for production of wood components. A total of 35 stems of young and mature cork oaks were sampled, live sawn into flitches, scanned using VTT’s WoodCIM^®, and the measured data computed by VTT’s PuuPilot software, allowing stem 3D reconstruction. Sawing simulations were run for 0.5 m and 1 m logs and the whole stem. Sawn products were (1) planks, (2) parquet, (3) lamparquet, and (4) external component of multilayer planks. Cork oak stems showed a moderate to small taper (mean 24 mm/m). Curviness varied between straight to significantly crooked stems (mean value 40 mm) Batch yields for the tested products ranged 25–43% and 37–50% for 0.5 m logs of young and mature trees, respectively; for 1 m logs, batch yields ranged 19–41% and 25–54%. When using the whole stem, batch yields were lower, ranging 11–38% and 15–50%. Higher yields were obtained for all log lengths and samples for production of lamparquet, parquet, and multilayer component.     

Logistic regression models for human-caused wildfire risk estimation: analysing the effect of the spatial accuracy in fire occurrence data

About 90% of the wildland fires occurred in Southern Europe are caused by human activities. In spite of these figures, the human factor hardly ever appears in the definition of operational fire risk systems due to the difficulty of characterising it. This paper describes two spatially explicit models that predict the probability of fire occurrence due to human causes for their integration into a comprehensive fire risk–mapping methodology. A logistic regression technique at 1 × 1 km grid resolution has been used to obtain these models in the region of Madrid, a highly populated area in the centre of Spain. Socio-economic data were used as predictive variables to spatially represent anthropogenic factors related to fire risk. Historical fire occurrence from 2000 to 2005 was used as the response variable. In order to analyse the effects of the spatial accuracy of the response variable on the model performance (significant variables and classification accuracy), two different models were defined. In the first model, fire ignition points (x, y coordinates) were used as response variable. This model was compared with another one (Kernel model) where the response variable was the density of ignition points and was obtained through a kernel density interpolation technique from fire ignition points randomly located within a 10 × 10 km grid, which is the standard spatial reference unit established by the Spanish Ministry of Environment, Rural and Marine Affairs to report fire location in the national official statistics. Validation of both models was accomplished using an independent set of fire ignition points (years 2006–2007). For the validation, we used the area under the curve (AUC) obtained by a receiver-operating system. The first model performs slightly better with a value of AUC of 0.70 as opposed to 0.67 for the Kernel model. Wildland–urban interface was selected by both models with high relative importance.     

Thinning intensity and growth response in SW-European Scots pine stands

The effect of different thinning intensities on growth and yield was studied in Pinus sylvestris L. stands at the south-western limit of its distribution area (Central Spain), using five long-term thinning trials. Data were analysed collectively considering several factors (trial, block, plot and period) as random effects. Total volume and volume increment decreased with thinning intensity, this loss being more significant in the case of moderate and heavy thinning. No difference was found among treatments for total basal area or the increment in basal area. The results revealed an optimum basal area (Assmann’s definition) between 85 and 100% of the basal area in unthinned plots. Volume growth loss associated with heavy thinnings (reduction of 18% in volume increment) was smaller than that reported in Central and Northern European regions (greater than 25%). Height increment was not influenced by thinning, whereas dominant and quadratic mean diameter increments increased with the thinning intensity. The response of diameter growth to thinning was greater at younger ages (less than 50 y) and in medium-sized trees.