Brooding Research Articles

Effects of different conditions on the artificial incubation effect and physiological indexes of redclaw crayfish eggs

We explored the effects of different conditions on the artificial incubation of redclaw crayfish eggs in an effort to improve this process. Samples at the egg and juvenile stages were selected. The samples at different stages were separated from the pleopods, then they were placed in incubator boxes and sterilized with different disinfectant solutions. The density was 300,400 and 500 eggs/incubator box, the vibration frequency was 11,16 and 26 vibrations/min, and the water circulation cycle was 2.1, 4.8 and 7.1 cycles/h. The results showed the eggs disinfected with 3000 ppm formaldehyde for 15 min had stronger antioxidant capacity. The hatching and survival rates of five pairs of appendage stage group were significantly lower than those of other groups. In the egg stage, acid phosphatase (ACP) level of compound eye pigmentation stage group was significantly higher than those of other groups. In the juvenile stage, malondialdehyde (MDA) content of five pairs of appendage stage group was significantly higher than those of other groups. The survival rate of 500 eggs/box group was significantly higher than that of other groups. In the egg stage, alkaline phosphatase (AKP) level of 400 eggs/box group was significantly higher than that of other groups. The survival rate of 11 vibrations/min group was significantly higher than that of other groups. In the egg stage, ACP and AKP levels of 11 vibrations/min group were significantly higher than those of 26 vibrations/min group. In the juvenile stage, superoxide dismutase (SOD), ACP and AKP levels of 11 vibrations/min group was significantly higher than those of 26 vibrations/min group. In the juvenile stage, AKP level of 4.8 cycles/h group was significantly lower than that of other groups. In conclusion, egg development at the stage after seven pairs of appendages, with a density of 400 eggs/box, vibration frequencies set at 11 vibrations/min achieved high hatching rates (93.58 %) and survival rates (75.67 %). Moreover, bronopol or hydrogen peroxide might have a better choice to replace formaldehyde if further exploration was conducted to reduce stimulation of the in vitro-grown egg. These conditions could be used on a large scale to optimize the production of redclaw crayfish.

Эффективность влияния пребиотической кормовой добавки на продуктивность, антиоксидантную защиту и иммунологический статус кур

Purpose. The study of the productive traits of chickens when fed with a prebiotic supplement that stimulates the antioxidant and immunological defenses of the body Materials and Methods. The studies were carried out in certified laboratories. The resulting digital material was processed using the statistical package Microsoft Excel, which provides verification of the reliability of the data using the Student's criterion. Results. It has been established that the introduction of the feed additive "LactuSuper" into the diet of laying hens of the Hisex Brown cross dramatically increases their productivity by 85 eggs in 10 weeks of the experiment, or by 1.2 eggs per positive laying hen, the egg-laying intensity – by 1.74%, feed savings – by 0.6 g per day per head, obtaining a hatching egg yield of 4% (97% compared to 93% of the control group). The balance of the feed additive "LactuSuper" with biologically active absorbed absorbable carotenoids in the yolk of the incubation eggs of the experimental group was 23.36% (P≤0.001), which was 16.9 µg/g in absolute values. Incubation of eggs showed a high hatch of chickens in both groups (82.44 and 85.27%), but in the experimental group, the excess in this indicator was 2.83%. High rates of production and quality of hatching eggs in the experimental group, apparently, are provided by the activation of metabolism in the body of chickens, as a result of feeding them the studied additive. Due to the antioxidant properties of the tested feed additive the activity of superoxide dismutase (SOD) increased by 11.22% (P≤0.01), glutathione peroxidase (GPO) – by 3.02% (P≤0.05), ceruloplasmin (CP) – by 16.58% (P≤0.01), total antioxidants (TOA) by 26.97% (P≤0.01), and malondialdehyde (MDA) activity decreased by 14.15% (P≤0,01). The level of T-lymphocytes responsible for cellular immunity increased by 12.61% (P≤0.01), and the content of B-lymphocytes characterizing humoral resistance increased by 6.83% (P≤0.05) relative to the control. An increase in the level of classical antibodies was recorded in the experimental group. Thus, the content of IgA and IgG increased by 17.26 (P≤0.01) and 7.62% (P≤0.05) compared with the control. The presence of IgM also exceeded the control values in the experimental group by 7.79% (P≤0.05). Conclusion. Thus, it was found that the feed additive "LactuSuper" developed by us contributed to the increase in the egg production of the parent flock and the quality of hatching eggs. The active substances of the prebiotic supplement ensured a decrease in the level of free radical lipid oxidation, which had a positive effect on the formation of the body's antioxidant defense, strengthening cellular and humoral immunity.

Effect of thermal manipulation on embryonic development, hatching process, and chick quality under heat-stress conditions

Thermal stress is a risk that threatens poultry welfare and productivity. Thermal manipulation during egg incubation is considered a prevention strategy used to mitigate the detrimental effects of high ambient temperatures on birds. This study aimed to investigate the impact of thermal manipulation, applied to chicken breeder's eggs during the incubation period, on embryonic development, hatching characteristics, and chick quality, as well as posthatch thermotolerance and performance. A total of 1,200 fertile eggs were randomly and equally assigned into 2 groups of 3 replicates (200 eggs/replicate), using a randomized experimental design followed by t test. The first group eggs (G1) were subjected to a commercial setter temperature of 37.5°C with 55% relative humidity (RH) throughout the incubation period (1-18 d) and served as a control, while the second group eggs (G2) were treated the same commercial setter conditions until the 11th day of the incubation, then the eggs were exposed to a higher temperature of 39.5°C with 60% RH for 4 h daily from the 12th to the 18th day of incubation. All eggs in both groups were exposed to the same temperature condition of 37.2°C with 70% RH from the 19th to the 22nd days of the incubation (hatching period). Three hundred hatched female chicks per each treatment group were transferred into a closed-system house and distributed randomly into 20 floor pens (15 birds per pen). At the 8th week of age, birds were exposed to a daily heat challenge by raising the temperature to 35°C for 6 h until the 18th week of the chick's age. According to the results, thermal manipulation at 12 to 18 d of egg incubation positively (P ≤ 0.05) affected several studied traits. It improved some embryonic development traits, such as embryonic weight and tibia length, as well as some hatching parameters, such as hatching time and pipped eggs. It also improved hatched chick quality traits, including the chick's weight, length, and activity. In addition, it enhanced the posthatch chick's thermotolerance and body weight. Hatched chicks of G2 had significantly (P ≤ 0.05) higher total protein, albumin, IgM, glucose, calcium, total antioxidant, and T3 than G1 chicks. They also had significantly (P=0.001) higher body weight (23%) at the 18th week of age than G1, as well as a lower feed conversion ratio (20.71%) than G1 chicks at 8 to 18 wk of age. Therefore, it is recommended to apply thermal manipulation during egg incubation, particularly at 12 to 18 d, for its positive effects on the pre- and posthatch performance.

Design and Temperature Control of an Ecological Hybrid Egg Incubator

In this article, we address the mechanical design and temperature control of an ecological egg incubator. A central component of the proposed incubator is the heating chamber, where the temperature is adjusted using a nickel/chromium heating element and a solar energy-based thermotank. Temperature regulation within the heating chamber is carried out through a PI controller. The tuning of the control gains is performed using the D-partition method, which allows obtaining stability regions of the closed-loop system in the presence of input time delay.

Biology and integrative taxonomy of leaf folder, Helcystogramma hibisci (Stainton, 1859): a pest of musk mallow, Abelmoschus moschatus (L.) Medik.

Abstract The leaf folder, Helcystogramma hibisci (Stainton, 1859) (Lepidoptera: Gelechiidae) is an oligophagous pest of different malvaceous plants. In this study, attempts have been made to study the biology and taxonomy of the insect infesting musk mallow (Abelmoschus moschatus), an aromatic cum medicinal plant in India, following an integrative approach based on external morphology, internal genitalia structures, and molecular taxonomy. In the initial stage, the larva scrapes the tender surface of the leaves, and later, grown-up larvae web the leaves by folding them longitudinally. The entire inner content of the leaves is eaten by the larvae and ultimately the leaves get dry. The identity of the pest species is confirmed through dissecting of the male and female genitalia of the pest species and molecular confirmation (GenBank accession number ON545806). By studying the biology of the insect, the egg incubation period, larval period, and pupal period were determined to be 4.70 ± 0.64, 13.66 ± 0.86, and 6.46 ± 0.61 (male), and 7.60 ± 0.71 days (female), respectively. The average fecundity and adult longevity of males and females were 61.20 ± 11.68 eggs/female, 4.93 ± 1.38 days (male), and 8.06 ± 1.56 days (female), respectively. During their fourth instar, male larvae have dark-colored gonads that are easily visible on the dorsal integument of the abdominal segment distinguishing them from female larvae. Further confirmation of the identification was done by keeping the larvae in separate vials until emergence; larvae with this dark-colored character could be confirmed to be males, while other the larvae developed into female moths. The head capsule width of the larval instars was 0.26 ± 0.02, 0.47 ± 0.04, 0.66 ± 0.03, 0.83 ± 0.06, and 1.13 ± 0.14 mm, respectively. The information is useful for proper identification and management of this pest in such a valuable and popular plant as musk mallow in India. To our best knowledge, this is the first description of this pest species from the Indian region along with molecular confirmation.

Dietary non-phytate phosphorus requirements for optimal productive and reproductive performance, and egg and tibial quality in egg-type duck breeders

Optimal dietary non-phytate phosphorus (NPP) is essential in poultry to maximise productive and reproductive performance, along with indices of egg and bone quality. This study aimed to establish the NPP requirements of egg-type duck breeders aged from 54 to 80 weeks on the following traits: egg production, egg incubation, egg quality, tibial characteristics, reproductive organ, plasma indices, and the expression of genes related to phosphorus absorption. Longyan duck breeders aged 54 weeks (n = 300) were randomly allotted to five treatments, each containing six replicates of 10 individually caged birds. Birds were fed corn-soybean meal-based diets containing 0.18, 0.25, 0.32, 0.38, and 0.45% NPP/kg for 27 weeks. The tested dietary NPP levels did not affect egg production or egg quality indices. The hatchling weight of ducklings increased (quadratic, P < 0.01) as dietary NPP level increased, and the highest value occurred with 0.25% NPP. The number of large yellow follicles (LYF), and the relative weights of LYF and ovary showed linear and quadratic responses to dietary NPP levels; the lowest number and relative weight of LYF occurred with 0.38% NPP, and the lowest ovarian weight was obtained with 0.25% NPP. There were no differences in tibial length, breaking strength, and mineral density in response to dietary NPP levels. In contrast, tibial content of Ca increased (linear, P < 0.01) with dietary NPP levels increasing from 0.18 to 0.45%, and the tibial content of P increased at 0.32% NPP and the higher dietary NPP levels. Plasma concentration of P showed a quadratic (P < 0.05) response to the dietary NPP levels, where the highest value was seen at 0.38% NPP. In conclusion, dietary NPP levels from 0.18 to 0.45% had no effects on egg production, and egg and tibial quality of duck breeders. The duck breeders fed a diet with 0.25% NPP showed the highest hatchling weight of their offspring, while those fed 0.38% NPP had the lowest number and relative weight of LYF. These results indicated that the diet with 0.25% NPP can be used in egg-type duck breeders to improve the hatchling weight of their offspring, without adverse effects on their productivity. The regression model indicated that the maximal hatchling weight of ducklings was obtained from duck breeders fed the diet with 0.30% NPP.

Effect of four eggshell repair materials on weight loss during incubation of white leghorn chicken eggs.

Egg weight loss during incubation is a key indicator used to monitor successful egg development and is closely related to hatchability and chick survival. Artificial incubation is one of the most important captive breeding techniques used in conservation efforts to bolster avian populations. To repair damage to the eggshell and ensure embryonic viability during incubation, a variety of repair coverings can be applied. This study tested the impact of four repair materials (nail polish, synthetic glue, medical dressing, and molten wax film) on egg weight loss during incubation. We found no impact on weight loss for coverings smaller than 35% of the eggshell surface, nor did we find any differences between covering types. The average egg weight loss decreased as the coverage area increased, and the weight loss did not differ when blunt versus sharp-end coverings were compared. Given the relative insensitivity of egg weight loss and survival to the type of patch material used, we concluded that the selection of material for the purpose of weight loss management could be based on practical considerations, such as ease of application and availability.

Development and Performance Evaluation of Home-Made Electric and Kerosene Lump Egg Incubator

This study was carried out to develop and evaluate the performance of home-made electric and kerosene lump egg incubator capable of incubating 150 eggs at predetermined temperature and humidity. The fabricated incubator consists of an egg cabinet made from MDF and plywood, egg tray made from mesh wire, TS-C700 temperature controller, hygrometer, a kerosene lump, water pan, and cooling fan system. The performances were evaluated in terms of hatchability rate, chick normality, fertility, and embryonic mortality rate. The experimental design used was simple descriptive statistics against the biological performance of the incubator. Naturally mated stock koekoek chicken eggs were used for evaluation of the developed incubator. The investigation revealed that the machine was evaluated at temperature of 37.50C and 60% relative humidity for the first 18 days of incubation and then temperature was lowered to 36.50C and increasing relative humidity to 65%. The ambient temperature of egg incubator has more effect on the interior temperature making the interior temperature varied. The average hatchability rate, fertility, embryonic mortality rate, and chick normality were 77.60%, 57.02%, 9.61% and 91.96% at average temperature of 37.240C and 60.75% of relative humidity were observed during incubation test. Depending on the performance results of the the incubator, it is concluded that the constructed incubator machine can be effectively and efficiently used by small and medium-scale poultry farmers.

Thermal conditioning of quail embryos has transgenerational and reversible long-term effects

BackgroundIn the current context of global warming, thermal manipulation of avian embryos has received increasing attention as a strategy to promote heat tolerance in avian species by simply increasing the egg incubation temperature. However, because of their likely epigenetic origin, thermal manipulation effects may last more than one generation with consequences for the poultry industry. In this work, a multigenerational and transgenerational analysis of thermal manipulation during embryogenesis was performed to uncover the long-term effects of such procedure.ResultsThermal manipulation repeated during 4 generations had an effect on hatchability, body weight, and weight of eggs laid in Japanese quails, with some effects increasing in importance over generations. Moreover, the effects on body weight and egg weight could be transmitted transgenerationally, suggesting non-genetic inheritance mechanisms. This hypothesis is reinforced by the observed reversion of the effect on growth after five unexposed generations. Interestingly, a beneficial effect of thermal manipulation on heat tolerance was observed a few days after hatching, but this effect was not transgenerational.ConclusionsOur multigenerational study showed that thermal conditioning of quail embryos has a beneficial effect on post-hatch heat tolerance hampered by transgenerational but reversible defects on growth. Assuming that no genetic variability underlies these changes, this study provides the first demonstration of epigenetic inheritance of traits induced by environmental temperature modification associated with long-term impacts in an avian species.

The effects of egg incubation temperature and parental cross on the swimming activity of juvenile brown trout Salmo trutta

Personality varies among individuals and is influenced by the environment. Here, we tested the hypothesis that egg incubation temperature had carry-over effects on swimming activity of juvenile brown trout, Salmo trutta. Eggs from different crosses involving anadromous and lacustrine-adfluvial parents were incubated under two temperature regimes, unheated (cold) or heated c. 2.5 °C above ambient temperature (warm), until first exogenous feeding. In the laboratory, we used open-field tests to quantify swimming activity in a new environment, and mirror-image tests to measure time spent swimming and resting motionless near a mirror, measures often used as proxies for aggression. These tests were conducted for two cohorts, with one tested in June 2018 and the other in June and August 2019, enabling us to test for repeatability and if differences persisted over the summer. In June, when adjusting for differences in body size between cold- and warm-incubated trout, we found that juvenile trout incubated as embryos at cold temperatures showed more swimming activity and took less time to initiate swimming for their size than those incubated in warm water. There were also body size and year effects but no effects of parental cross. For August, none of the incubation temperature effects observed in June persisted, but cold-incubated trout spent a larger proportion of their time motionless near the mirror than warm-incubated trout and there was a general body size effect on time to initiate swimming. The lack of any persistent effects of incubation temperature between June and August suggests that the effect is ephemeral. Notwithstanding, these results support the hypothesis that incubation temperature has short-term effects on activity of juvenile of brown trout during their first summer.Significance StatementWe studied the effect of embryonic temperature on juvenile fish behavior, focusing on swimming activity under different conditions. Brown trout eggs were incubated under two temperature regimes, cold and warm. We show that juvenile trout originating from cold conditions as embryos spent a greater proportion of time swimming and less time to initiate swimming than trout originating from warm conditions. These effects were present in June but not August, which suggests that the effect is short-lived, and occurs during the first summer when mortality of juveniles is high. The duration of the effects needs further study as our previous studies have shown persistent embryonic temperature effects on metabolism, body shape, reproductive potential and emigration of subsequent life stages of salmonids. These results also have bearing on ongoing climate change as even small differences in embryonic temperature may have ecological consequences for subsequent life stages.

Effect of In-Ovo Organic Zinc Injected and High Temperature During the Late Stage of Chicken Eggs Incubation on Post Hatch Performance

Effect of In-Ovo Organic Zinc Injected and High Temperature During the Late Stage of Chicken Eggs Incubation on Post Hatch Performance

Effect of Bee Bread on Corticosterone Level in Rat Dams Exposed to Gestational Heat Stress.

Environmental temperature rises are powerful stimuli that can alter both the sympathetic nervous system and the hypothalamic-pituitary-adrenocortical axis (HPA). Heat stress has been shown to harm pregnancy outcomes such as causing spontaneous abortion, low birth weight, growth retardation and stillbirth. Supplementation of bee bread in pregnant rats under heat stress exposure has been shown to improve the pregnancy outcomes. However, whether supplementation of bee bread during heat stress exposure may also reduce the level of the stress hormone, corticosterone has yet been reported. Therefore, this study aims to determine the effect of bee bread on corticosterone level, progesterone level, oestradiol level and zonation of the adrenal cortex of pregnant rats under heat stress exposure. Pregnant rats were randomly categorised into four groups (n = 6): Control (C: standard feeding), Treatment 1 (T1: 0.5 g bee bread/kg body weight/day), Treatment 2 (T2: standard feeding with heat exposure), and Treatment 3 (T3: 0.5 g bee bread/kg body weight/day with heat exposure). Bee bread (0.5 g/kg body weight/day) was force-fed to pregnant rats through oral gavage beginning on day 0 of pregnancy and continuing until delivery. Heat stress was generated experimentally by putting both T2 and T3 rats in an egg incubator for 45 min daily at a temperature of 43°C till delivery. On a postnatal Day 21, dams were euthanised to assess serum corticosterone, progesterone, oestradiol levels and adrenal gland histology. Rats in the T2 group had a significantly (P < 0.05) increase in the zona fasciculata thickness (94.95 ± 1.55 μm) and higher corticosterone levels (49.57 ± 1.57 ng/mL) compared with control. However, supplementation of bee bread during heat stress was able to show an improvement in adrenal zona fasciculata thickness by decreasing to 79.89 ± 3.08 μm and corticosterone level reduced to 35.31 ± 1.73 ng/mL significantly (P < 0.05). Therefore, these findings may imply that bee bread is effective as a neutralizer in lowering the production of stress hormone.

Microflora of hatching eggs and ways of its formation

In this study, the results were obtained reflecting the content of the genetic material of bacteria in incubation eggs. Given the widespread use of chicken embryos in medicine, veterinary medicine and pharmacology, the identification and identification of microorganisms is an important task. In the course of the study, a quantitative and qualitative analysis of the composition of bacteria in various tissues of incubation eggs was carried out. Three average mixed samples of each typical category were selected: chorion-allantois shell (HAO) on the 8th day of incubation, yolk sacs on the 13th, 18th and 20th days of incubation. The study was conducted using real-time PCR (real-time PCR). Sampling and sample preparation were carried out in accordance with established standards. The data obtained are important to take into account when using incubation eggs as an experimental model or for obtaining biological products. As a result of this study, the content of bacterial genetic material in various tissues of incubation eggs was established, which is important for assessing the safety and quality of these eggs when they are used in medical, veterinary and pharmacological studies. The real-time PCR method made it possible to conduct a quantitative and qualitative analysis of the composition of bacteria, which is an important step in studying the identification of microorganisms in incubation eggs. The established rules and standards for sampling and sample preparation ensure the reliability and accuracy of the data obtained.

Біологічні особливості та перспективи штучного відтворення вирезуба (Rutilus frisii frisii Nordman, 1840) в Україні (огляд)

Purpose. The main goal of the thematic review was the analysis and generalization of literary sources on the peculiarities of its biology, technological aspects of artificial reproduction and growing of vyrezub (Rutilus frisii frisii Nordman, 1840) for the restoration of its natural population in water bodies of Ukraine. To evaluate the perspectives of artificial reproduction and growing of vyrezub in aquaculture of Ukraine. Findings. As a result of human impact on river networks of Ukraine, the abundance of vyrezub significantly decreased, it has become a rare and at the same time an endangered species. According to retrospective data, vyrezub previously belonged to the widespread commercial species of the Dnipro and Southern Bug rivers. The biological features of this species have been analyzed, the observance of which can allow obtaining viable fish seeds in aquaculture conditions. The adaptive possibilities of vyrezub to artificial conditions of reproduction have been reviewed. Historical information on the reproduction of this species over the last century has been analyzed. On the territory of Ukraine, first attempts to artificially reproduce vyrezub were carried out by specialists of Ukrcherrybvod. According to the results of studies of Ukrainian scientists, several stages of artificial reproduction of vyrezub have been identified, namely: taking spawners from natural water bodies, obtaining eggs and sperm, incubation of eggs in incubation devices, obtaining 6 g fish seeds, release of viable juveniles into natural water bodies. However, the works on artificial reproduction of vyrezub were not successful, which was the reason for their complete cessation. In particular, this species is promising for growing in polyculture, as it does not create intense trophic competition with most objects of freshwater aquaculture, and as a result of the consumption of mollusks will reduce the likelihood of the spread of some invasive fish diseases. Practical value. The review of information sources on various aspects of the use of vyrezub in aquaculture will contribute to the development of a system of separate links of the technology of its cultivation for the needs of rearing in the conditions of aquaculture enterprises and stocking of internal water bodies with viable juveniles. Key words: vyrezub (Rutilus frisii frisii Nord­man, 1840), aquaculture, biocontrol effect, artificial reproduction, viable juveniles, stocking, restoration of population abundance.

Development of standards for artificial reproduction of pike perch Sander lucioperca in the West Siberian Fishery Basin (Novosibirsk region)

The results of fish-breeding works on artificial reproduction of sander — Stizostedion lucioperca in the West Siberian fishery basin, carried out at the fish-breeding and production base of LLC “Rybkhoz”, are presented. In the course of the research, standards for artificial reproduction of sander were worked out, taking into account the indicators approved for other regions of the country by the Order of the Ministry of Agriculture of the Russian Federation dated 30.01.2015 № 25, “On approval of the Methodology for calculating the volume of extraction (catch) of aquatic biological resources necessary to ensure the conservation of aquatic biological resources and ensure the activities of fish farms, when fishing for aquaculture (fish farming)”, as well as according to literary sources. Such biotechnical indicators have not been developed for the West Siberian Fishery basin before. The process is briefly described, including trapping, transportation and bonitization of producers, their injection, obtaining eggs, fertilization, de-gluing and incubation, rearing of sander juveniles up to 0.5 g. The producers selected for artificial reproduction were divided into three experimental groups by weight categories, which were subsequently kept in the same conditions to obtain reliable results fertilization and incubation of eggs. Recommendations are given on the selection of the most suitable producers of sander with an average weight of 1.7 kg, superior to other weight groups in terms of relative fertility, the percentage of maturation of producers and the percentage of fertilization of eggs obtained from them. Recommendations are also given on the conditions for the rearing of juvenile and its release into the reservoirs of the Novosibirsk region.

Olive Ridley Sea Turtle Incubation in Natural Conditions Is Possible on Guatemalan Beaches

The Guatemalan strategy for sea turtle conservation was defined by the National Council of Protected Areas (CONAP) in 1989. Hatcheries lie at the core of this strategy: egg collectors are allowed to deliver 20% of a nest to a hatchery in exchange for selling or eating the remaining eggs. Consequently, nearly 100% of nests are collected, with no nests being left on the beaches. Hatchery design promotes shading using roofs made from vegetation. The logic behind this recommendation is that the natural incubation of eggs is supposedly impossible due to the overly high temperatures on the beach. However, changing the incubation temperature of sea turtle eggs can profoundly alter the sex ratio in sea turtles with temperature-dependent sex determination. It can also modify the physiology or behavior of juvenile turtles. Here, we test whether incubation in natural conditions is possible on Guatemalan beaches, and for the first time, we determine the thermal reaction norm of embryo growth to ensure hatching success in sea turtles. We show that incubation in natural conditions is possible since three out of the four monitored nests produced hatchlings. We urge the Guatemala National Council of Protected Areas to reevaluate its strategy for sea turtle conservation in Guatemala in light of these results.

Calcium anacardate and its association with citric acid in diets for meat-type breeding quails.

The purpose of this study was to evaluate the effects of using calcium anacardate (CaA) as a source of anacardic acid and its association with citric acid (CA) in diets for breeding quails on the performance, the egg quality, incubation parameters, and progeny performance. Were used 540 quails European quails (Coturnix coturnix coturnix) that were 21 weeks old, housed in laying cages based on a completely randomized design, with nine treatments and six replications of 10 quails per parcel, with each experimental unit having eight females and two males. The following additions to the diet were evaluated: 1, no addition (control diet); 2, 0.25% CaA; 3, 0.25% CaA and 0.25% CA; 4, 0.50% CaA; 5, 0.50% CaA and 0.25% CA; 6, 0.50% CaA and 0.50% CA; 7, 0.75% CaA; 8, 0.75% CaA and 0.25% CA; and 9, 0.75% CaA and 0.50% CA. The treatments had no significant effects on the performance of the breeding quails, incubation parameters, and progeny performance. For egg quality, there was only an effect on yolk lipid oxidation, which was lower for eggs from quails fed the diets containing 0.50% CaA and 0.25% CA, 0.50% CaA and 0.50% CA, or 0.75% CaA alone, when compared with the control group. Considering that including CaA with or without CA in diets for breeding quails only affected yolk lipid oxidation, it can be recommend including 0.50% CaA and 0.25% CA or 0.75% CaA alone to mitigate oxidative damage in the yolk of fertile eggs.

Nematocidal Activity of Ethanol and Aqueous Extracts of Persea americana Seeds against Heligmosomoides polygyrus using the Worm Microtracker Method.

Infections with gastrointestinal helminths constitute a serious obstacle to the good health of the local population in most African Countries. The aim of this study was to evaluate the anthelminthic activity of Persea americana ethanol and aqueous extracts against Heligmosomoides polygyrus using the worm microtracker. Aqueous and ethanolic extracts of P. americana were prepared. Different concentrations of the extracts were tested against the egg and larvae stages of H. polygyrus using an automated high-throughput method. Briefly, embryonated eggs and larvae of this parasite were obtained after the incubation of fresh eggs at 25°C for 24, 48, and 96 hours for embryonated eggs, L1 and L2 larvae, respectively. One hundred microliters of the plant extracts at various concentrations were put in contact in a 96-well microplate with a suspension of 100 embryonated eggs in a total volume of 200 μL and incubated in a worm microtracker where the motility of the worms was recorded every 30 minutes for the ovicidal activity. The final tested extract concentration was 5, 2.5, 1.25, 0.625, and 0.3125 mg/mL, whereas ringer solution (0.95%) and 1.5% Dimethyl sulfoxide (DMSO) were used as negative controls and levamisole as positive control. The same method was used for larvicidal activities. The anthelmintic activity was determined using the average movement of the worms in the tested product compared with the negative control (1.5% DMSO and ringer solution). The egg hatching rates of H. polygyrus had IC50 of 0.49 mg/mL (95% confidence interval: 71.70-92.03) and 0.22 mg/mL (95% confidence interval: 74.28-86.18) for the ethanol and aqueous extract, respectively. These IC50 indicate that the aqueous extract is more active for the inhibition of hatching at a 95% confidence interval. The aqueous and ethanol extracts presented mean inhibitory hatching rates of 78.33 ± 1.67% and 75.67 ± 1.15% at 5 mg/mL, respectively, with no significant differences. The highest percentage of inhibition of L1 larva was observed at 5 mg/mL with 89 ± 2.3%and 85 ± 2.7% for the ethanol and aqueous extracts, respectively. The lowest percentage of inhibition was observed at 0.3125 mg/mL, with 54.67 ± 3.38% and 49 ± 2.64% for the ethanol and aqueous extract, respectively. No significant differences were observed between the two extracts at 5 mg/mL with an inhibitory percentage of 90.67 ± 3.05% (ethanol) and 89.33 ± 2.08% (aqueous). Extracts of P. americana seeds possess nematocidal activity, however, further in silico and in vivo investigations are necessary to confirm their anthelminthic activity.

Brood Rearing, Induced Spawning and Egg Incubation of Channa Striatus in an Indoor System With a Note to Its Second Breeding in the Same Season

Channa striatus broods were raised in ferro-cement cisterns at stocking density 2.0 kg/m3. GSI (ovary) of above brood was lowest during December (1.0670.157) and highest during June (9.340.331). Matured broods were induced bred with WOVA- FH (a GnRH based inducing agent) in a rectangular FRP tank. The breeding response was recorded as 88% with spawning fecundity 26.871±6.301 x 103 (ranged 17.142 x 103-36.585 x 103) and spawn recovery rate was 20.238± 5.074 x 103 (ranged 14.056 x 103- 30.365 x 103). The spent broods were further reared in the ferro-cement cistern for further study. The GSI of spent brood were enhanced from 5.0130.870 to 8.88± 0.318 within a period of 45 days and the fish could be induced bred for 2nd time after 60 days of initial spawning. The breeding success for 2nd instance was recorded 30% with spawning fecundity of 21.636±4.789 x 103 (ranged 18.71 x 103- 27.16 x 103) and spawn recovery rate of 16.086± 2.56 x 103 (ranged between 14.270 x 103-19.014 x 103). The GSI of spent fish after second breeding was again reduced to 4.8380.442.

Year-Round Spawning, Filial Cannibalism, and Embryonic and Larval Development of the Coral Reef Fish Orchid Dottyback, Pseudochromis fridmani

Aquaculture of marine ornamental fish could potentially reduce the fishing pressure on wild stocks by the global aquarium trade, but its expansion is often constrained by the limited understanding on the biology and early life history of candidate species. The orchid dottyback Pseudochromis fridmani is a valuable and popular marine ornamental fish, but scientific reports on its baseline biology, especially the egg filial cannibalistic behaviour, are scarce. The present study documented key aspects of reproductive biology and early ontogeny of P. fridmani in captivity, including reproductive behaviour, patterns of spawning and filial cannibalism throughout a 12-month period by seven pairs of brood fish, as well as the embryonic and larval development. The results showed that the captive spawning of the broodstock pairs generally occurred every 5–11 days, most commonly every 6–8 days, throughout a year. Despite feeding the brood fish to satiation throughout the data collection period, the average monthly rate of egg filial cannibalism reached 55 ± 37%, but the cannibalism frequency appeared to be pair-specific. The egg incubation duration was approximately 96 h at 27 ± 1 °C, and the development of embryos from cleavage, blastula, gastrula, and segmentation to the pharyngula stage is herein described in detail. The newly hatched P. fridmani larvae possessed important structures and organs for first feeding, including pigmented eyes, developed jaws, and a straight-tube gut. The 0 to 14 days post-hatching (DPH) period appeared to be an important larval stage, as P. fridmani larvae were observed to complete major changes in morphology, gut development, and phototactic behaviour by 14 DPH. Under the culture conditions of this study, the earliest transition to the juvenile stage was observed on 31 DPH, and the majority of fish became juveniles by 56 DPH. The results of this study inform baseline aquaculture production protocols and direct future research, particularly to reduce filial cannibalism through broodstock management and to improve larval culture through supporting the early ontogenetic development of P. fridmani. Additionally, these findings form a foundation for further studying the biology and ecology of P. fridmani in the wild.