Mass migration of juvenile Biomphalaria glabrata snails bred under semi-natural conditions

For the development of studies on snail interspecific competition special in-door laboratory channels were built. In the all five channels seeded with adult specimens of Biomphalaria glabrata mass migration of juvenile snails outside the water was observed. Most of the migrant snails presented apertural lamellae. Data collected during the period of two years, showed the regression of the migration phenomenon and the disappearance of the lamellate snails.

Juvenile hormone III and nutrition effects on spermatogenesis in the 4th instar nymphs of Panstrongylus megistus (Hemiptera: Reduviidae)

When 4th instar nymphs of Panstrongylus megistus are fed with a saturant blood meal, there is an intense proliferation of the spermatogonia. At the end of the intermoult, the older spermatogonial cysts differentiate into 1st primary spermatocyte cysts. In the nymphs deprived of the blood meal this evolution is not observed, but a small growth of the testicular follicles occurs, due to a few mitotic divisions. This growth is observed at least, until 25 days after ecdysis. Since day 15, an autolytic process starts in the older spermatogonial cysts. The presence of exogenous juvenile hormone III (JH III) does not promote the development of the germ cells in the fasting insects. There is only a small growth of the testicular follicles and the autolytic process is also observed. In the precocious adults obtained by allatectomy or precocene II treatment, germ cells are observed in all development stages, except packed and elongated spermatozoa bundels.

Biomorphological Alterations Induced by an Anti-juvenile Hormonal Compound, 2-(2-EthoxyEthoxy)Ethyl Furfuryl Ether, on Three Species of Triatominae Larvae (Hemiptera, Reduviidae)

Applied topically to larvae of Rhodnius prolixus Stal, Triatoma infestans (Klug) and Panstrongylus herreri Wygodzinsky, vectors of Trypanosoma cruzi, the causative agent of Chagas'disease, a synthetic, furan-containing anti-juvenile hormonal compound, 2-(2-ethoxyethoxy)ethyl furfuryl ether induced a variety of biomorphological alterations, including precocious metamorphosis into small adultoids with adult abdominal cuticle, ocelli, as well as rudimentary adultoid wings. Some adultoids died during ecdysis and were confined within the old cuticle. The extension of these biomorphological responses is discussed in terms of the complexity of the action of anti-juvenile hormonal compounds during the development of triatomines

Absonifibula estuarina sp. n. (Monogenea: Diclidophoridae) parasite of juvenile Cynoscion guatucupa (Osteichthyes) from southwestern Atlantic Ocean

Absonifibula estuarina sp. n. (Diclidophoridae, Absonifibulinae), is described from the gills of juvenile striped weakfish, Cynoscion guatucupa (Cuvier), from the southwestern Atlantic, Argentinean coast. This marine fish migrates to estuarine areas to spawn where exclusively juveniles are found parasitized; adult fish in marine water were never found to be parasitized by this monogenean. A. estuarina sp. n. is characterized mainly by the pedunculate clamps dissimilar in size, the shape of anterior jaw with sclerite 'a' attached to a sub-trapezoidal lamellate extension and fused to sclerites 'c' and 'd'. It differs from Absonifibula bychowskyi Lawler & Overstreet, 1976, the only known species of the genus, in the shape and arrangement of the genital corona, which is armed with six similar hooks disposed in circle and the sub-trapezoidal shape of lamellate extension ('b'). The restriction to juvenile sciaenids is a shared feature among the Absonifibulinae indicating an estuary-dependent life cycle.

Pharmacodynamics of mefloquine and praziquantel combination therapy in mice harbouring juvenile and adult Schistosoma mansoni

Praziquantel (PZQ) is currently the only drug widely used for the treatment of schistosomiasis, but the antimalarial drug mefloquine (Mef) possesses interesting antischistosomal properties. Combination therapy with these two drugs has been suggested as a strategy for transmission control, as PZQ is active against adult worms and Mef is active against schistosomula. To examine the efficacy of combination therapy, Schistosoma mansoni-reinfected mice were separated into seven groups: untreated (I), treated with PZQ in doses of 200 mg/kg (II) or 1,000 mg/kg (III), treated with Mef in doses of 200 mg/kg (IV) or 400 mg/kg (V); each dose was divided equally and given on two consecutive days. Group VI was treated with doses of PZQ + Mef as in groups II and IV, respectively, while group VII was treated with PZQ + Mef as in groups III and V, respectively. PZQ + Mef at the reduced doses of 200 mg/kg each enhanced the therapeutic efficacy over the reduced PZQ dose alone as shown by a very high reduction in the total numbers of mature worms (95% vs. 49%), immature worms (96% vs. 29%) and the complete eradication of immature females, mature females and immature eggs. The reduction in worm burden was associated with the healing of hepatic granulomatous lesions and the normalisation of all liver enzymes. Therefore, the use of Mef with PZQ is more effective than PZQ alone and should be considered for clinical trials in humans as a potential treatment regimen to prevent treatment failures in areas with high rates of schistosomiasis.

Accidental intoxication of the infant-juvenile population in households: profiles of emergency care

OBJECTIVE Analyzing profiles of intoxication and accidental poisoning of infant-juvenile population (0-24 years) in the household, treated at a reference facility for Emergency and Primary Care, during the year 2013. METHOD A descriptive, cross-sectional study. Data were analyzed using Epi-Info, by way of simple and bivariate analyzes. The project was approved by the Research Ethics Committee (protocol 405.578). RESULTS There were 45 intoxications, with a prevalence of males (60.0%), aged 1-4 years (71.1%). Among children under one, there was a higher frequency of pesticide poisoning (66.6%), between the ages of 1-4 by cleaning products (34.4%), and between 5-9 years of age by pharmacological substances (66.6%). The primary assistance was provided only at health institutions, with hospital admissions in 24.4% of the cases. CONCLUSION The importance of prevention through legislation is evident, in order to ensure greater safety in packaging of various products, and community awareness to eliminate risks in the household environment.

Growth, yield, water and effluent quality in ponds with different management during tambaqui juvenile production

The objective of this work was to evaluate the effect of pond management on fish feed, growth, yield, survival, and water and effluent quality, during tambaqui (Colossoma macropomum) juvenile production. Fish were distributed in nine 600 m² earthen ponds, at a density of 8 fish per m²; the rearing period was 60 days. Three different pond management were applied: limed and fertilized (LimFer), limed (Lim), and natural (Nat). Fish were fed with a commercial ration containing 34% crude protein three times daily. There were no significant differences in fish growth or yield. Three main items found in tambaqui stomach were insect, zooplankton and ration, without a significant difference among treatments in proportion. Alkalinity, hardness, and CO2 were greater in LimFer and Lim ponds. Chlorophyll a, transparency, ammonia, nitrite, temperature, and dissolved oxygen of pond water were not significantly different among treatments. Biochemical oxygen demand, total phosphorus, orthophosphate, ammonia, and nitrite were significantly greater in effluents from LimFer ponds. Pond fertilization should be avoided, because growth and yield were similar among the three pond management systems tested; besides, it produces a more impacting effluent.

Interactions of juvenile Lumbricus terrestris with adults and their burrow systems in a two-dimensional microcosm

The objective of this work was to evaluate interactions of Lumbricus terrestris juveniles with adults and with inherited burrow systems. An experiment was set up using a two dimensional Evans' boxes microcosm. Adult L. terrestris were added to 16 boxes (one individual per box) and kept in darkness at 17ºC along with eight unoccupied boxes for two months. The adult L. terrestris were removed from eight randomly selected boxes, and L. terrestris juveniles were added (one juvenile per box), composing three treatments with eight replicates: 1, with an adult in an inherited burrow (ABJ); 2, alone in an inherited burrow (BJ); and 3, alone in a previously uninhabited box (J). The proportion of juveniles occupying adult burrows observed was significantly different in treatments ABJ (48%) and BJ (75%). The mean mass of juveniles at experimental termination differed significantly among treatments and was greater in treatment J (4.04±0.39 g) in comparison to the BJ (3.09±0.93 g) and ABJ treatments (2.13±0.64 g). Results suggest a negative influence of both the presence of an adult and its burrow system on juvenile growth. Intraspecific competition partially explained this, but further investigation is required to examine how an inherited environment (i.e. burrow) could negatively affect the growth of juveniles.

Feeding rate and frequency on juvenile pompano growth

The objective of this work was to evaluate the ideal feeding rate and frequency for juvenile pompano (Trachinotus marginatus). Two experiments were carried out in a completely randomized design, with three replicates each. In experiment I, 25 fish (4.8±0.6 g and 6.48±0.01 cm) were stocked in 15 tanks (50 L) during 21 days and fed 4, 8, 12, 16, and 20% body weight per day. In experiment II, 20 fish (4.1±0.1 g and 6.6±0.1 cm) were stocked in 15 tanks (40 L) during 28 days and fed 2, 6, 8, and 10 times a day. The tested feeding rates and frequencies did not influence survival. Final weight and length in experiment I were significantly lower in fish fed 4% body weight per day, whereas in experiment II only weight was significantly lower in fish fed 2 and 6 times a day. At the end of both experiments, apparent feed conversion showed significant difference, with the worst value observed for fish fed 20% body weight per day in experiment I and 2 times a day in experiment II. Juvenile pompano show better growth performance when fed 8% body weight per day and 8 times a day.

Eugenol as an anesthetic for juvenile common snook

The objective of this work was to evaluate the efficacy of eugenol as an anesthetic for juvenile common snook, and to determine the minimum effective concentration for use in handling procedures. In the first trial, juvenile common snook were subjected to immersion baths at 25, 50, 75, 100, 125, and 150 mg L-1 eugenol concentrations, after which induction and recovery times were evaluated. In the second experiment, the lethal exposure time (LT50) at 75 mg L-1 was estimated. Minimum effective eugenol concentration was 50 mg L-1, andthe stage of deep anesthesia and recovery were, respectively, reached at 126.3 and 208.8 s. At 75 mg L-1, LT50 was 1,314 s, and induction time and recovery were also satisfactory; however, fish cannot tolerate over 229 s exposure.

JUVENILE-MATURE GENETIC CORRELATIONS IN Pinus taeda CLONES PROPAGATED VIA SOMATIC EMBRYOGENESIS

ABSTRACT This study aimed to estimate the genetic correlation among selection ages (juvenile - adult) and efficiency of early selection for the height, diameter, and volume traits of individuals from Pinus taeda families propagated via somatic embryogenesis. This study was carried out by genetic-statistical analysis, estimation procedure of variance (Reml), and prediction components of breeding values (Blup), using the Selegen-Reml/Blup software. Genetic correlations among juvenile ages and rotation age were performed by applying the linear model developed by Lambeth (1980). In accordance with results of the established model, the early selection can be performed in clones of Pinus taeda with high selection efficiency. Ages from 4 to 6 years old are enough to select Pinus taeda clones propagated via somatic embryogenesis for harvesting at 8 and 12 years old; and 6 to 10 years old are enough to select them for harvesting at 20 years old. On the basis of the genetic correlations estimates from the environments, the clones' selection of Pinus taeda propagated via somatic embryogenesis should be developed specifically for each environment. The clones' selection can be performed considering the diameter due to the high correlation between volume and diameter.

Juvenile dynamics of the endemic and rare Enterolobium glaziovii Benth. (Mimosaceae) around reproductive trees in the Atlantic forest, Brazil

Studies on the regeneration and seedling mortality of rare tree species are important, but scarce. The aim of this study was to investigate the annual variation in recruitment, growth and mortality of juveniles of Enterolobium glaziovii Benth., a rare tree species from the Brazilian Atlantic Rain Forest. All seedlings and juveniles around four reproductive trees were labeled and their fate was followed from 1996 to 1999. There were no annual differences in juveniles' recruitment below and beyond the parental crown, but juveniles' survival and growth were lower below than beyond of the parental tree crowns. Small individuals (< 15 cm tall) showed the greatest mortality and the lowest growth, followed by medium (from 15 to 50 cm tall) and large ones (> 50 cm tall). Large juveniles were more widely dispersed from the conspecific parental tree than were medium and small ones. This suggests that distance dependent mortality of juveniles mediated by the parental tree is an important cause of spacing shifts associated with the growth of small individuals of E. glaziovii into large ones. Widely dispersed juveniles may escape the high mortality associated with pathogens, herbivores or seed predators concentrated around adult conspecifics. The negative influence of the parental tree on its juveniles may explain the sparse distribution of its adults in the forest.

The effect of methotrexate and azathioprine on the serum levels of IgA-a1-antitrypsin complex in juvenile chronic arthritis

In the present study we investigated the influence of methotrexate (MTX) and azathioprine (AZA) on the serum levels of the IgA-a1-antitrypsin (IgA-AT) complex in patients with the systemic form of juvenile chronic arthritis (JCA). Fifty-six JCA patients (22 treated with MTX, 18 treated with AZA, and 16 not treated with any immunosuppressive agent) were enrolled in the study. MTX dosage ranged from 0.3 to 0.5 mg kg-1 week-1, while AZA was given daily at an average dose of 1 mg/kg. MTX was given for 13 months (SD = 7 months) whereas AZA for 11 months (SD = 6 months). The average value of the complex was higher in JCA patients than in both control groups (0.74 ± 0.73 U vs 0.37 ± 0.13 U (control children), P<0.001 and vs 0.23 ± 0.12 U (control adults), P<0.001). Values exceeding the normal range were found in twenty-two JCA patients (39.4%). Serum IgA-AT level was lowest in the MTX group compared to AZA and non-treated patients (0.56 ± 0.24 U, 0.76 ± 0.43 U, 0.95 ± 0.52 U, respectively, P<0.05). IgA values exceeding normal levels for age were found in 14% of the patients. A correlation between the levels of the IgA-AT complex and C-reactive protein (r = 0.43, P<0.01), a1-acid-glycoprotein (r = 0.45, P<0.01), a1-antichymotrypsin (r = 0.52, P<0.01), a1-antitrypsin (r = 0.40, P<0.01) and IgA (r = 0.56, P<0.01) was established

Insect juvenile hormone: from "status quo" to high society

Juvenile hormone (JH) exerts pleiotropic functions during insect life cycles. The regulation of JH biosynthesis by neuropeptides and biogenic amines, as well as the transport of JH by specific binding proteins is now well understood. In contrast, comprehending its mode of action on target organs is still hampered by the difficulties in isolating specific receptors. In concert with ecdysteroids, JH orchestrates molting and metamorphosis, and its modulatory function in molting processes has gained it the attribute "status quo" hormone. Whereas the metamorphic role of JH appears to have been widely conserved, its role in reproduction has been subject to many modifications. In many species, JH stimulates vitellogenin synthesis and uptake. In mosquitoes, however, this function has been transferred to ecdysteroids, and JH primes the ecdysteroid response of developing follicles. As reproduction includes a variety of specific behaviors, including migration and diapause, JH has come to function as a master regulator in insect reproduction. The peak of pleiotropy was definitely reached in insects exhibiting facultative polymorphisms. In wing-dimorphic crickets, differential activation of JH esterase determines wing length. The evolution of sociality in Isoptera and Hymenoptera has also extensively relied on JH. In primitively social wasps and bumble bees, JH integrates dominance position with reproductive status. In highly social insects, such as the honey bee, JH has lost its gonadotropic role and now regulates division of labor in the worker caste. Its metamorphic role has been extensively explored in the morphological differentiation of queens and workers, and in the generation of worker polymorphism, such as observed in ants.

Heart rate and body weight alterations in juvenile specimens of the tropical land snail Megalobulimus sanctipauli during dormancy

The time course of heart rate and body weight alterations during the natural period of dormancy were determined in active feeding and dormant juvenile specimens of Megalobulimus sanctipauli. In both groups, heart rate markedly decreased during the first 40 days of dormancy, tending to stabilize thereafter. This time period coincided with the decrease in environmental temperature during autumn-winter. At the end of the dormancy period, surviving active feeding and dormant snails showed a significant decrease in heart rate which, however, was significantly greater in the latter group. Total body weight decreased concomitantly with heart rate in dormant snails but remained constant in active feeding snails. Body hydration induced significant increases in weight and heart rate in surviving dormant snails. Feeding following hydration promoted a new significant increase in heart rate but not in weight. These results indicate that the decrease in heart rate observed in juvenile specimens of M. sanctipauli during dormancy may be due to at least three factors: 1) decrease in environmental temperature during autumn-winter, 2) starvation which leads to the depletion of endogenous fuel reserves and to a probable decrease in hemolymph nutrient levels, and 3) dehydration which leads to a probable decrease in hemolymph volume and venous return and/or to an increase in hemolymph osmolarity.