Evaluación de procedimientos no letales para el análisis gonadal del caracol West Indian, Cittarium pica (Gastropoda: Trochida)

Effects of temperature, salinity and aerial exposure on predation and lysosomal stability of the dogwhelk Thais (Nucella) lapillus (L.)

Deterrent effect of Gymnodinium catenatum Graham PSP-toxins on grazing performance of marine copepods

Developmental larval stages of the geoduck Panopea globosa (Dall, 1898) are described for the first time. Growth rate, survival, and the length—size relationship were also assessed at 22°C in five independently reared cohorts. Clearance rates (CR), ingestion rates (IR), dry weight, and organic weight of select larval stages were quantified in two additional runs. Clearance rates and IR were evaluated as a function of cell concentration (50, 100, 200 and 300 cells/µL) of the chrysophyte Isochrysis sp. (clone T-ISO) using static systems. Conspicuous larval stages appeared after 20 h (trochophore), 24 h (straight hinge or “D”), 5–6 day (early umboned), 9–10 days (intermediate umboned), 11–12 days (late umboned), and 12–14 days (pediveliger). The larval period for P. globosa lasted between 12 days and 14 days, and the shell length recorded at settlement ranged from 332–356 µm (mean, 343 ± 4.2 µm). The overall average gross growth rate of the five larval cohorts was ∼20 µm/day. The relationship between larval shell length (in micrometers) and organic weight (in micrograms) followed a power function with an exponent value of 2.43, whereas the relationship between dry weight and organic weight was linear. Survival rate was approximately 50% in three larval cohorts and 20% in two cohorts. Clearance rates were inversely related to microalgal concentration regardless of larval size, and ranged from 0.3–1.5 µL/h (D larvae) to 15–59 µL/h (pediveliger, 330µm). On the other hand, IR increased with increasing algal concentration, and reached maximum values at 200 cells/µL, except in D-hinge larvae, which exhibited a maximum IR at all concentrations tested. At the highest concentration (300 cells/µL), premetamorphic larvae inhibited their IR. Overall, IR increased from 57–85 cells/h (D-hinge larvae) to 40- or 50-fold when larvae reached the premetamorphic stage. The current study revealed that P. globosa has a short larval period and high survival rate, and withstands a wide range of food concentrations without inhibiting its IR. Therefore, this species appears to be an excellent candidate for hatchery production.

This study experimentally determined the role of local diatom and dinoflagellate diets and theirfatty acid composition on the survival, ingestion, and egg production rates of the copepod Centropages furcatus from Bahía de La Paz. The fatty acid profiles of the diatoms Odontella longicruris and Chaetoceros sp., and of the dinoflagellates Scrippsiella sp., Gyrodinium sp., and Prorocentrum micans were determined. After incubating at 24 °C in darkness during 24 h, survival within all phytoplankton diets was > 90%. Dinoflagellate diets provided higher egg production (>25 eggs female-1 day-1) than diatom diets (<10 eggsfemale-1 day-1). No significant differences were observed in the ingestion rates when fed dinoflagellates or diatoms, which varied between 400 and 900 ng C copepod-1 h-1. Higher egg production with dinoflagellate diets suggests better food quality, which may be attributed to higher proportions of the fatty acids 18:4 (n-3) and 22:6 (n-3). These results suggest that when C. furcatus predominantly graze on dinoflagellates eggproduction will increase. Higher abundances of dinoflagellates in the La Paz bay could be coupled with higher egg production of the copepod C. furcatus.

Sex identification of the ornamental amazon fish Astronotus ocellatus by videoceloscopy and gonadal biopsy

Comparison of larval bioenergetics of two marine gastropods with widely differing lengths of planktonic life, Thais haemastoma canaliculata (Gray) and Crepidula fornicata (L.)

The combined effects of initial stocking density (2, 5, 10 individuals [inds]/mL) and feed ration (5×103, 20×103, 40×103, 100×103 cells·ind−1·d−1) on growth, survival, and ingestion rate of larval geoduck clams Panopea generosa fed Isochrysis sp. (Tahitian strain, TISO clone) were assessed. All three measurements were significantly affected by stocking density, ration, and their interaction. Growth rate ranged from 2.15 to 3.85 μm/d in the various treatments. It increased with stocking density at 5×103 cells·ind−1·d−1, was significantly higher at 5 than at 2 inds/mL at 20×103 cells·ind−1·d−1, and was significantly higher at 2 and 5 than at 10 inds/mL at 40×103 and 100×103 cells·ind−1·d−1. Growth rate increased with increasing ration up to 40×103 cells·ind−1·d−1 at 2 and 5 inds/mL, but decreased with increasing ration at 10 inds/mL. Percent survival over the experiment duration (23 d) ranged from 7% to 56% in the various treatments and generally decreased with increasing stocking density. There was no significant effect of ration on percent survival at 2 and 5 inds/mL, but survival decreased with increasing ration at 10 inds/mL. Ingestion rate ranged from 2×103 to 29×103 cells·ind−1·d−1 in the various treatments. It was not significantly affected by stocking density at 5×103 and 20×103 cells·ind−1·d−1, but larvae held at 2 and 5 inds/mL had significantly higher ingestion rates than those stocked at 10 inds/mL at 40×103 and 100×103 cells·ind−1·d−1. Ingestion rate increased with ration at 2 and 5 inds/mL but was not significantly affected by ration at 10 inds/mL. Due to the significant interaction of the treatment factors, stocking density-specific ration levels must be selected in order to maximize growth and survival.

Quantitative studies of feeding and nutrition during larval development of the coral reef asteroid Acanthaster planci (L.)

We present a model of the survival-maximizing foraging behavior of an animal searching in patches for hidden prey with a clumped distribution. We assume the forager to be Bayesian: it updates its statistical estimate of prey number in the current patch while foraging. When it arrives at the parch, it has an expectation of the patch's quality, which equals the average patch quality in the environment While foraging, the forager uses its information about the time spent searching in the patch and how many prey has been caught during this time. It can estimate both the instantaneous intake rate and the potential intake rate during the rest of the parch visit. When prey distribution is clumped, potential intake rate may increase with time spent in the parch if prey is caught in the near future. Being optimal, a Bayesian forager should therefore base its patch-leaving decision on the estimated potential patch value, not on the instantaneous parch value. When patch value is measured in survival rate and mortality may occur either as starvation or predation, the patch should be abandoned when the forager estimates that its potential survival rate dining the rest of the patch visit equals the long term survival rate in the environment This means that the instantaneous intake rate, when the patch is left, is nor constant but is an increasing function of searching time in the patch. Therefore, the giving-up densities of prey in the patches will also be higher the longer the search times. The giving-up densities are therefore expected to be an increasing, but humped, function of initial prey densities. These are properties of Bayesian foraging behavior not included in previous empirical studies and model tests.

Background: Coccidiosis is the infectious disease with the greatest economic impact in poultry production. Additionally, chemotherapeutic growth promoters are being substituted for safer alternative strategies. Objective: To evaluate the effect of feeding oleoresins from chili pepper (Capsicum annuum) and turmeric (Curcuma longa L.) on the performance, survival rate, and the Productive Efficiency Index of broilers from 1 to 21d challenged by Eimeria sp. Methods: A total of 700 male 1-dayold chicks (Cobb 500) challenged with Eimeria sp, were assigned to a completely randomized design with four treatments: (1) negative control diet, without anticoccidial agent or growth promoters; (2) control diet+0.05% salinomycin; (3) negative control diet+100g/ton; and (4) negative control diet +140g/ton of test product (Curcuma longa L. plus Capsicum annuum oleoresins). Results: Body weight, weight gain, feed conversion and Productive Efficiency Index did not differ between broilers fed anticoccidial chemotherapeutics and oleoresins. In addition, there was no difference in feed intake and survival rate between dietary treatments. Conclusion: Broilers supplemented with chili pepper and turmeric oleoresins from 1 to 21d present similar body weight, weight gain, feed conversion, and Productive Efficiency Index compared to broilers supplemented with chemotherapeutic anticoccidials without affecting feed intake or survival rate.

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Instantaneous salinity reductions affect the survival and feeding rates of the co-occurring copepods Acartia tonsa Dana and A. clausi Giesbrecht differently

Two 5-wk experiments, using a total of 270 pigs (avg initial wt of 16.1 and 13.11b), were conducted to determine the dose-response relationship between Streptococcus faecium additions to drinking water and performance of newly weaned pigs. In experiment 1, treatments were: 1) untreated control; 2, 3, and 4) .5, 2.5, and 4.5 x 109 CFU of S. faecillm/pig/d; 5) antibioticfed positive control (CSP250 and CUS04)' Bacterial content of feces collected from the pigs on d 7, 14, and 21 indicated that antibiotic feeding greatly reduced fecal content of streptococci. S. faecium given in the water (.5, 2.5, or 4.5 x 10 CFU/pig/d) slightly increased the CFU of streptococci in the feces. Giving S. faecillm in the water or antibiotics in the feed did not reduce fecal content of coliform bacteria. Antibiotic feeding improved feed intake, growth rate, and efficiency of gain when compared to the untreated control. Pigs given the highest level of S. faecium addition to the water (i.e., 4.5 x 10^9 had performance that was intermediate to that of the untreated control and positive control. In experiment 2, dosages of S. faecium were spread further apart. Treatments were: 1) untreated negative control; 2,3, and 4) 5 x 107, 5 X 109, and 5 x 1011 CFU of S. faecium/pig/d; and 5) antibiotic-fed positive control. Streptococci content of the feces was increased by giving S. faecillm in the water. However, total coliform content was not affected by giving S. faecium or antibiotics. Antibiotic feeding improved rate of gain, feed intake, and efficiency of gain, but giving S. faecium did not improve performance of pigs compared to those given the untreated control.; Swine Day, Manhattan, KS, November 16, 1989

PurposeRadiation-induced oral mucositis limits the delivery of high-dose radiation to head and neck cancer. This study investigated the effectiveness of epicatechin (EC), a component of green tea extracts, on radiation-induced oral mucositis in vitro and in vivo.Experimental DesignThe effect of EC on radiation-induced cytotoxicity was analyzed in the human keratinocyte line HaCaT. Radiation-induced apoptosis, change in mitochondrial membrane potential (MMP), reactive oxygen species (ROS) generation and changes in the signaling pathway were investigated. In vivo therapeutic effects of EC for oral mucositis were explored in a rat model. Rats were monitored by daily inspections of the oral cavity, amount of oral intake, weight change and survival rate. For histopathologic evaluation, hematoxylin-eosin staining and TUNEL staining were performed.ResultsEC significantly inhibited radiation-induced apoptosis, change of MMP, and intracellular ROS generation in HaCaT cells. EC treatment markedly attenuated the expression of p-JNK, p-38, and cleaved caspase-3 after irradiation in the HaCaT cells. Rats with radiation-induced oral mucositis showed decreased oral intake, weight and survival rate, but oral administration of EC significantly restored all three parameters. Histopathologic changes were significantly decreased in the EC-treated irradiated rats. TUNEL staining of rat oral mucosa revealed that EC treatment significantly decreased radiation-induced apoptotic cells.ConclusionsThis study suggests that EC significantly inhibited radiation-induced apoptosis in keratinocytes and rat oral mucosa and may be a safe and effective candidate treatment for the prevention of radiation-induced mucositis.

The addition of atractant in feed is expected could improve snakehead respond,andincreasing its growth. The Aims of this study are to knowfeed respond, the feed intake, growth, feed efficiency, and survival rate of snakehead fry given by feed with different various of atractant.This research was conducted on Jun-July 2016 at Laboratorium Dasar Perikanan Program Study Budidaya Perairan, Agriculture Faculty, Sriwijaya University. This research was using completely randomized designed with four treatments and three replications, consist offeed without attractants (P0), feed with 2% fish meal addition (P1), feed with 2% squid meal addition (P2), and feed with 2% shrimp meal addition (P3). Fish maintained for 30 days and fed four times a day (at 07.00, 11.00, 14.00 and 17.00) are at satiation. Parameters of this research are feed respond, the feed intake, growth, feed efficiency and survival rate of snakehead fry. The result showed that given of atractant effect to feed intake and absolute growth of weight (Channa striata) fry, yet did not give effect to snakehead respond significantly, for absolute growth of length, feed efficency and survival rate. The best treatment was P3 (feed with 2% shrimp meal addition) with feed intake was 17.19 g, absolute growth of weight was 0.52 g, absolute growth of length was 1.33 centimetre, survival rate was 73.33% and feed efficiency was 48.97%. Physical and chemical of media maintanace, temperature 25-28oC, pH was 6.35-6.96, DO was 5.05-5.96 mg.L-1 and ammonia 0.02-0.17 mg.L-1. Keywords : Atractant, Channa striata, Growth and feed respond