Live Eggs Research Articles

The effect of transport temperature and duration on survival and growth of house cricket nymphs and eggs

Abstract The transport of live insects is becoming increasingly common within the food and feed industry. However, very little information is available as to its effects on the insects themselves. The aim of this study was to monitor how variation in transport conditions, such as duration of transport and external temperature and humidity, directly and indirectly affect the survival and growth of nymphs of the house cricket, Acheta domesticus. In addition, we investigated the effect of external temperature on the viability of eggs upon completion of a transport event. We investigated how four different temperatures (5 °C, 15 °C, 25 °C, 35 °C) and four possible transport durations (1, 2, 3, 6 days) affected survival and growth of the cricket nymphs. To gain insight into the potential transport of eggs, its effect on egg hatch-rate was studied by storing eggs at three different temperatures (6 °C, 18 °C and 30 °C) before moving the eggs to optimal hatching conditions. We found that humidity remained constant inside the transport boxes and was different from the exterior humidity. Temperature had a significant effect on nymph survival and growth. The extreme temperatures negatively affected nymph survival, and increased temperature was correlated with increased growth. The development of eggs was also sensitive to temperature, and transport of eggs at suboptimal temperatures prolonged incubation time considerably. Finally, based on the results of this study, we discuss temperature optimisation as the most critical factor to consider during transport of live house cricket nymphs and eggs.

New Technique for Identification of Ichthyoplankton and Its Application in Biomonitoring Studies, Management and Conservation of Neotropical Fish.

Despite significant advancements in ichthyoplankton collection and data processing, challenges persist in the taxonomic identification of these organisms, particularly their eggs. To overcome these challenges, a novel technique has been developed to facilitate the identification of live eggs collected directly in wild. This user-friendly technique includes the collection, processing of the material, and field incubation. Sampling must be conducted using a pelagic net towed at low speed, preferably during early evening. The material processing involves pre-sorting and sorting to remove eggs and larvae. The separated eggs, kept in an aerated bowl, can be identified based on their morphological and meristic characteristics. Unidentified eggs can be placed in plastic bags with oxygen and incubated directly in the aquatic environment for 48-72 h. After this incubation period, the hatched larvae at the yolk-sac or preflexion stage, are identified to the lowest possible taxonomic level. Depending on the study's purpose, hatched larvae and field-collected larvae can be transported to research centers for further development, released back into the natural environment, or fixed to complete the collection. The application of this technique supports management and monitoring programs by identifying spawning areas through egg identification, forming broodstock, and replenishing threatened species, thereby enhancing scientific collections of ichthyoplankton. Additionally, it reduces mortality in ichthyoplankton techniques, including endangered species. Therefore, we believe that this novel taxonomic technique for identifying live ichthyoplankton represents a paradigm shift in the monitoring, management, and conservation of fish, as well as in ecological stewardship and advances in this area of research.

Drugs for head lice.

Pediculosis capitis (head lice infestations) occur in all age groups, but especially in elementary school children. In most cases, transmission occurs by head-to-head contact. Pharmacologic treatment is recommended for persons with live lice or eggs (nits) within 1 cm of the scalp. Topical pediculicides should be tried first. Oral therapy is occasionally required for refractory infestations.

Comparison of Economic Feasibility of Different Chicken Genotypes Under On-Station Condition

The main objective of this study was to compare the economic feasibility of Cosmopolitan (C), Improved Horro (H), ♂Improved Horro*Cosmopolitan♀ (HC), and ♂Cosmopolitan*Improved Horro♀ (CH) in reference to Indigenous (L) and Koekoek (KK) genotypes. The study employed a completely randomized design, with a total of 180 samples (36/genotype) for egg sales, 54 samples (9/genotype) for live bird sales, and 36 samples (6/genotype) for meat sales. Each genotype's eggs, live birds, and meat sales were triplicate. All data were analyzed using the GLM model in SAS Software. At 8–24weeks, KK had the highest feed intake (AFI8–24) compared to HC, CH, and C; nevertheless, L had the lowest next to H. At 8–52 weeks, KK, CH, and HC hens had the highest feed intake (AFI8–52), whereas L, H and C hens had the lowest. L had the lowest meat yield (MYD) next to H, but the KK had the highest between 8 and 24 weeks followed by the HC, CH, and C. Live genotypes and meats sales showed that KK had the highest costs (TC1) and meat sales (TC2) followed by HC, CH and C, but the lowest for H and L. KK had the lowest total live sale return (TR1), whereas H had the highest followed by L, CH, HC, and C.L had the lowest total meat sale return (TR2), while KK had the highest followed by HC, CH, C, and H.L hen had the lowest total egg sale return (TR3) followed by C, while the highest was achieved by CH hen followed by H, KK and HC.H had the highest live net return (NR1) followed by L, CH, C, and HC, while KK had the lowest. Meat net return (NR2) was the lowest for L and the highest for KK followed by HC, CH, C, and H. H had the highest net return of egg sales (NR3) followed by CH, C, KK, and HC, but L had negatively least. H registered the highest cost-benefit ratio (TR1/TC1vs.TR3/TC3) compared to other genotypes (live chicken and eggs). KK showed the highest cost-benefit ratio (TR2/TC2) followed by HC, CH, C and H, whereas L had the lowest for meat. In conclusion, the net return and cost-benefit ratio for live genotypes, meats and eggs were notably positive and feasible except L had (for egg case) negative net return and cost-benefit ratio.

Temporal dynamics of the egg bank of Aedes aegypti (Diptera: Culicidae) in the winter-spring transition in a temperate region.

In temperate regions, the populations of Aedes aegypti (L.) (Diptera: Culicidae) remain in the egg stage during the winter. In Buenos Aires, Argentina, a temperate region in the southern limit of Ae. aegypti distribution, the start of the next reproductive season and the rate of increase of the adult population depend on the egg bank that remains after the winter. This study aimed to analyze the mortality, field-hatching, and survival of eggs exposed to field conditions representative of those that occur in nature. In addition, the post-exposure hatching response of the eggs was assessed. Four egg batches were exposed to natural conditions starting in mid-winter and were recovered progressively after 3, 6, 9, and 12 weeks. One egg batch (initial control) was not exposed in the field and remained under laboratory conditions. After the exposure period, the recovered intact, collapsed, and hatched eggs were counted. Intact eggs were immersed three times in the laboratory to study their hatching response. Progressive increases in the proportion of lost (presumably by predation), dead, and hatched eggs in successive egg batches were recorded. Field-hatching was recorded from late winter onwards. The first hatchings occurred in conditions probably not favorable to complete development into reproductive adults. A progressive decrease in live eggs was observed, with 51% of the recovered eggs alive after 12 weeks of exposure. In the laboratory, the hatching response in the first immersion was low for the initial control and for the eggs exposed for 3 weeks, and increased for successive cohorts. The results confirm that the survival of Ae. aegypti eggs in the winter-spring transition ensures persistence throughout the next favorable season in Buenos Aires City. The observed inhibition to hatch of the first batches might relate to a photoperiod-induced diapause, as observed in previous studies.

Metabolic Rates of Rainbow Trout Eggs in Reconstructed Salmonid Egg Pockets

In situ evaluations of the metabolic rates (i.e., respiration and excretion) of salmonid eggs are mostly indirect, focusing on the sampling of hyporheic water from wild or artificial nests. Comparatively, experimental studies carried out under controlled, laboratory conditions are less abundant due to methodological difficulties. This study presents a novel experimental setup aimed to address this issue and enable the measurement of oxygen and dissolved inorganic nitrogen fluxes in simulated rainbow trout (O. mykiss) egg pockets. The experimental setup consists of reconstructed egg pockets in cylindrical cores under flow-through conditions. Live and dead eyed-stage eggs were incubated in a natural, sterilised gravel substrate. Hyporheic water circulation was ensured using peristaltic pumps, with the possibility to collect and analyse inflowing and outflowing water for chemical analyses. Microcosm incubations, with closed respirometry of eggs in water alone, were also carried out in order to infer the importance of microbial respiration in the simulated egg pockets. The results show an increasing trend in oxygen demand, due to the development of biofilm in the reconstructed egg pockets and increased egg respiration rates. Moreover, egg pockets showed positive ammonium net fluxes connected with the advancing developmental egg stage, while nitrate removal peaked during the last phase of the experiment, mainly due to the formation of oxic-hypoxic interfaces, leading to couple nitrification–denitrification processes. The suggested approach enables to test a number of in situ situations, including the effects of extreme hydrological conditions, sediment clogging and sudden changes in water chemistry or temperature on the survival and metabolic performances of nests, at different egg development stages.

An investigation into the combination of the parasitic nematode Phasmarhabditis hermaphrodita and cedarwood oil to control pestiferous slugs

Several slug species are voracious pests of agricultural crops in northern Europe and are difficult to control. The parasitic nematode Phasmarhabditis hermaphrodita has been developed as a slug control product, but there is little information about whether it could be combined with other control methods (such as essential oils) to enhance its efficacy. Here, we carried out experiments in propagators with lettuce at three different time periods (July, September and October), and tested the following treatments: water (untreated control), cedarwood oil, P. hermaphrodita, cedarwood oil and P. hermaphrodita, and Tween 80 (used as an emulsifier for the cedarwood oil solution). Lettuce was grown in propagators with either 10 Deroceras reticulatum or 5 Arion vulgaris and the percentage of lettuce eaten over 14 days (as well as weight, the number of live slugs and eggs produced) was recorded. Cedarwood oil reduced slug damage, slug numbers and slug eggs in the experiments with D. reticulatum, and P. hermaphrodita performed well in two out of three experiments. The mixture of P. hermaphrodita and cedarwood oil was superior in reducing the proportion of lettuce eaten compared to single doses of each treatment in one out of three trials. In propagators with A. vulgaris all treatments performed poorly. In summary, P. hermaphrodita and/or cedarwood can be used to reduce damage by D. reticulatum, but are ineffective at controlling A. vulgaris. Slugs from the genus Arion continue to be a difficult group to control.

Description and pathology of a new genus and species of fish blood fluke (Digenea: Aporocotylidae Odhner, 1912) infecting white mullet, Mugil curema Valenciennes, 1836 (Mugiliformes: Mugilidae) in Mobile Bay (northern Gulf of Mexico) with a phylogenetic analysis.

Three fish blood flukes (Aporocotylidae Odhner, 1912) infect mullets (Mugiliformes: Mugilidae): Cardicola mugilis Yamaguti, 1970 and Plethorchis acanthus Martin, 1975 infect striped mullet, Mugil cephalus Linnaeus, 1758 in the Central Pacific Ocean (Hawaiian Islands) and Brisbane River (Australia), respectively; Cardicola brasiliensis Knoff & Amato, 1992 infects Lebranche mullet, Mugil liza Valenciennes, 1836 from the Southwestern Atlantic Ocean (Brazil). White mullets were cast-netted from the mouth of Deer River, a coastal saltmarsh of Mobile Bay, in the north-central Gulf of Mexico and examined for blood fluke infections. Specimens of Mugilitrema labowskiae Warren & Bullard n. gen., n. sp. were found infecting the endocardial surface and inter-trabecular spaces of the atrium, ventricle, and bulbous arteriosus. The new genus and species differ from all other aporocotylids by having the combination of two post-caecal testes, a uterus with straight ascending and descending portions, and a common genital pore. The 28S analysis recovered the new species and P.acanthus as sister taxa and Aporocotylidae as monophyletic. Carditis associated with intense infections comprised endocardial hyperplasia, resulting in a thickened cardiac endothelium. Probable dead or deteriorating eggs in the myocardium were encapsulated by granulomas composed of epithelioid histiocytes. Live eggs infected the afferent artery of gill filaments and were associated with varied hyperplasia of the overlying epithelium and haemorrhaging from the afferent artery in high-intensity infections. The new species is the first aporocotylid infecting a mullet from the northwestern Atlantic Ocean and only the second description of demonstrable endocarditis attributed to an adult fish blood fluke infection.

In Ovo Feeding Techniques of Green Nanoparticles of Silver and Probiotics: Evaluation of Performance, Physiological, and Microbiological Responses of Hatched One-Day-Old Broiler Chicks

The aim of this study was to investigate the effects of the in ovo feeding of green nanoparticles of silver (Nano-Ag), probiotics, and their combination on hatchability, carcass criteria and internal organs, biochemical parameters, and cecal microbial populations in hatched one-day-old chicks. On day 18 of incubation, 250 live embryo eggs were weighed and randomly assigned to one of five treatment groups: a negative control group, a positive control group consisting of chicks injected with 0.2 mL physiological saline, a group consisting of chicks injected with 0.2 mL Nano-Ag, a group consisting of chicks injected with 0.2 mL probiotics (Bifidobacterium spp.), and a group consisting of chicks injected with 0.2 mL combination of Nano-Ag and probiotics (1:1). The results showed that the in ovo injection of Nano-Ag or probiotics, alone or in combination, had no effect on hatchability, live body weight, or internal organs but improved (p < 0.05) chick carcass yield compared to the control groups. Furthermore, in ovo feeding decreased (p < 0.05) serum levels of cholesterol, triglycerides, urea, creatinine, alanine aminotransferase, and aspartate aminotransferase, as well as cecal E. coli, but increased Bifidobacterium spp. when compared to the control groups. Based on these findings, in ovo injections of green Nano-Ag and probiotics, either alone or in combination, have the potential to improve chick health and balance the microbial populations in hatched one-day-old chicks.

In ovo administration of the Marek's disease vaccine in conjunction with 25-hydroxyvitamin D3 and its subsequent effects on the performance and immunity-related characteristics of Ross 708 broiler hatchlings1,2,3

The combined effects of the in ovo injection of commercial Marek's disease vaccine (MDV) and various levels of 25-hydroxyvitamin D3 (25OHD3) on the hatch variables, immunological measurements, and gene expression of Ross 708 hatchling broilers were investigated. A total of 5 in ovo injection treatments that were applied at 18 d of incubation (doi) included: 1) noninjected (control); or a 50 μL solution volume of 2) MDV alone; or MDV combined with 3) 0.6 μg of 25OHD3; 4) 1.2 μg of 25OHD3; or 5) 2.4 μg of 25OHD3. At hatch, hatchability of set and live embryonated eggs, hatchling body weight, hatch residue analysis, serum IgY and alpha-1 acid glycoprotein (AGP) concentrations, and the expression of genes related to immunity (INFα, INFβ, INFγ, TLR-3, and TLR-21) and vitamin D3 activity (1 α-hydroxylase, 24 hydroxylase, and vitamin D receptor) were determined. No significant treatment differences were observed for hatchability of set and live embryonated eggs, or for serum IgY and AGP concentrations. However, hatchling body weight was higher when MDV was combined with either 1.2 or 2.4 μg of 25OHD3 than when MDV was provided alone or in combination with 0.6 μg of 25OHD3. Also, in comparison to the noninjected treatment group, the expression of the genes for 1 α-hydroxylase and 24 hydroxylase was improved when MDV was combined with either 1.2 or 2.4 μg of 25OHD3. Lastly, expression of the genes linked to viral detection (TLR-3) and antibody production (INF-β) was increased in those treatments that contained any level of 25OHD3. These results indicate that in comparison to controls, the effects of MDV were observed to be greater on hatchling BW and splenic gene expression when it was administered in combination with the 1.2 or 2.4 μg doses of 25OHD3. Further research is needed to determine the posthatch effects of the administration of various levels of 25OHD3 in combination with MDV.

Effects of the in ovo injection of an Escherichia coli vaccine on the hatchability and quality characteristics of commercial layer hatchlings

In the commercial egg industry, avian pathogenic Escherichia coli (APEC) can lead to significant economic loss. The Poulvac E. coli vaccine (PECV) is a commercially available attenuated live vaccine commonly applied via spray or drinking water to protect against losses associated with colibacillosis. The PECV has not been tested in layer hatching eggs using in ovo injection. Therefore, the purpose of this experiment was to determine the effects of injecting 50 μL of different doses of the PECV into Hy-Line W-36-layer hatching eggs on the hatchability and quality characteristics of hatchlings. At 18 d of incubation (DOI), treatments included 1 noninjected and 1 diluent-injected control. Furthermore, PECV treatments included a full dose (4.4×108E. coli CFU) or serial dilutions of the full dose to produce 4.4×106, 4.4×104, or 4.4×102 CFU doses of E. coli. In ovo injections targeted the amnion. Percent hatchability of live embryonated eggs (HI), percent residue eggs, hatchling mortality, and female chick whole and yolk-free BW, relative yolk sac weight, and body length were among the variables examined. Treatment significantly (P < 0.0001) affected HI, with HI being highest in the control groups (97.3% in the noninjected and 94.2% in the diluent-injected), and with HI values being 89.0, 88.9, 84.4, and 71.2% in the 4.4×102, 4.4×104, 4.4×106, and 4.4×108 CFU E. coli dose treatments, respectively. The percentage of live embryos that did not complete hatch but that pipped internally (P=0.024) or externally (P < 0.0001) were significantly affected by treatment, with percentages being highest in the 4.4×108 CFU treatment. Female chick body length was significantly (P < 0.0001) affected by treatment and was longer in both control groups and in the 1×102 CFU E. coli treatment in comparison to all other treatments. Yolk-free female chick BW was significantly (P=0.034) affected by treatment and was lower in the 4.4×106 CFU and 4.4×108 CFU treatments when compared to the diluent-injected control group. An increase in the E. coli concentration administered in the amnion of embryonated layer hatching eggs at 18 DOI decreased hatch success and female chick yolk-free BW and body length.

About the survival of muksun embryos and larvae of the depending on the time of insemination of the eggs after collection

The goal of the research was to study the viability of the offspring of the Coregonus muksun obtained from eggs inseminated at different time (-from 0 to 220 min) after collection.Classical fish breeding methods were used in the work: eggs was inseminated by dry method, incubation was carried out in sieves and modified Weiss devices with a volume of 1 l, juveniles were grown in 60 liter pools with a stocking density of 150 ind./pool, artificial diet and artemia nauplii served as food.Such studies in fish breeding practice are carried out for the first time, which determines their novelty.As a result of the research, an almost linear dependence of the survival rate of the offspring of muksun on the time of insemination of ovulated eggs was established with a very high degree of approximation reliability (R2) for embryos 0,906, larvae 0,846. The best survival rate of embryos and larvae was obtained in experimental variants in which eggs were inseminated in the first hour after collection. The proportion of live eggs at the end of incubation and larvae after 38 days of rearing was 57,5-58,9% and 78-84%, respectively. The survival rate of embryos and larvae in the experimental variants in which eggs were inseminated 80-100 minutes from the moment of collection were in the range of 40,1-42,2% and 49,4-50,1%, respectively; for 120-160 minutes 9,4-15,3% and 45,3-47,6%; for 180-220 min the survival rate of caviar did not exceed 5,0%, larvae- 45,6%.The practical significance of the work lies in determining the optimal period between the collection and insemination of eggs with the least risk to the viability of the offspring, which is of great importance in works on the artificial reproduction and cultivation of valuable fish species.

Size- and position-dependent cytoplasm viscoelasticity through hydrodynamic interactions with the cell surface

Many studies of cytoplasm rheology have focused on small components in the submicrometer scale. However, the cytoplasm also baths large organelles like nuclei, microtubule asters, or spindles that often take significant portions of cells and move across the cytoplasm to regulate cell division or polarization. Here, we translated passive components of sizes ranging from few up to ~50 percents of the cell diameter, through the vast cytoplasm of live sea urchin eggs, with calibrated magnetic forces. Creep and relaxation responses indicate that for objects larger than the micron size, the cytoplasm behaves as a Jeffreys material, viscoelastic at short timescales, and fluidizing at longer times. However, as component size approached that of cells, cytoplasm viscoelastic resistance increased in a nonmonotonic manner. Flow analysis and simulations suggest that this size-dependent viscoelasticity emerges from hydrodynamic interactions between the moving object and the static cell surface. This effect also yields to position-dependent viscoelasticity with objects initially closer to the cell surface being harder to displace. These findings suggest that the cytoplasm hydrodynamically couples large organelles to the cell surface to restrain their motion, with important implications for cell shape sensing and cellular organization.

State of marine biota in the water area of the Muchke Bay’s Coal Terminal of the Tatar Strait

An analysis of the species composition of phytoplankton and ichthyoplankton was carried out for the first time in the port water area of the Muchke Bay (Tatar Strait) in autumn. The species composition, distribution features and structure of macrozoobenthos were considered. Phytoplankton density is evenly distributed in the study area. The density of diatoms reached 97 % of the total phytoplankton density, and the biomass was 99 %. The microalgae Sceletonema costatum (Greville) Cleve, 1873 and Cylindrotheca closterium (Ehrenberg) Reimann &amp; J.C.Lewin, 1964, species that live in polluted waters, were discovered. The development of phytoplankton in the autumn period was active, but the peak of flowering was not observed. Ichthyoplankton in October 2017 is represented by live eggs of Limanda sakhalinensis (Schmidt, 1904) (8 ind./m3), in September 2018 - by the larvae of Hexagrammos stelleri Tilesius, 1810 (0.003-0.056 ind./m3) and H. octogrammus (Pallas, 1814) (0.01-0.077 ind./m3). Up to 85 representatives of macrozoobenthos were registered from the research area, including 40 species of Polychaeta, 19 ones of Crustacea, 16 species of Mollusca, 5 ones of Echinodermata and 5 species of other fauna groups. After dredging, a decrease in the species diversity of phytoplankton, ichthyoplankton and macrozoobenthos was found in the samples.

Variable Effects of the In Ovo Administration of an Escherichia coli Vaccine in the Amnion or Air Cell on Commercial Layer Embryo and Hatchling Development

The effects of injecting the Poulvac E. coli vaccine (PECV) into either the air cell (AC) or amnion (AM) at different dosages at 18 days of incubation (DOI) on Hy-Line W-36-layer embryo and hatchling development were investigated. Serial dilutions of the PECV in diluent provided either 6.5 × 104, 6.5 × 103, 6.5 × 102, or 6.5 × 101 CFU dosages of E. coli. A diluent only injection treatment was included as a control. A total of 19 live embryonated eggs in each of 10 treatment groups were represented on each of 16 replicate levels (3040 total) in the hatcher unit. At 19 DOI, swabs of the AM indicated that the 6.5 × 101 and 6.5 × 102 CFU dosages provided a 50% level of PECV presence, whereas the 6.5 × 103 and 6.5 × 104 CFU dosages provided a 100% level of PECV presence. Conversely, only the 6.5 × 103 and 6.5 × 104 CFU dosages provided a 50% level of PECV presence in the AC. At all E. coli dosage levels, injection in the AM led to higher percentages of live or dead embryos that failed to pip (PEIS) (p = 0.001) or complete hatch (PEPE) (p ≤ 0.001) and a lower percentage of live fully hatched chicks (HI) (p ≤ 0.001), when compared to those injected in the AC. Like HI, significantly lower percentages of female hatchlings were also observed at 22 DOI for the AM compared to the AC injection, for all dosages except for the 6.5 × 102 CFU dosage. However, at all the dosages above the 6.5 × 101 CFU dosage, the AM injection resulted in a lower mean hatchling body weight (p = 0.010) at 22 DOI. In conclusion, E. coli populations were more prevalent in the AM than in the AC after the injection of the PECV in those sites. Furthermore, the injection of the PECV in the AM at all E. coli dosages generally increased late embryo mortality and decreased hatchability and hatchling body weight in comparison to an AC injection. It is concluded that the negative impact of the in ovo administration of the PECV in the AM at 18 DOI on the hatch process is dose dependent. However, effects of an increase in AC dosages and a decrease in AM dosages should be further investigated.

Effects of the In Ovo and Dietary Supplementation of L-Ascorbic Acid on the Growth Performance, Inflammatory Response, and Eye L-Ascorbic Acid Concentrations in Ross 708 Broiler Chickens.

Simple SummaryL-ascorbic acid (L-AA), known as vitamin C, is involved in several metabolic process, including bone formation, antioxidant activity, and inflammatory response. It is well documented that the antioxidant capacity and immunity of broilers are enhanced in response to the dietary or in ovo administration of L-AA. The aim of the current study was to determine the effects the in ovo or dietary administration of L-AA on the post hatch performance, plasma nitric oxide, and eye L-AA concentrations of Ross 708 broilers. At 17 days of incubation, the following treatments were administered: non-injected or sham-injected (100 μL of saline) controls, or the injection of either 12 or 25 mg of L-AA suspended in 100 μL of saline. In addition, chicks were fed a commercial diet with or without 200 mg/kg of supplemental L-AA. The results of the current study revealed that the eye concentrations of L-AA were higher in males in comparison to females. Additionally, 12 mg of L-AA decreased plasma nitric oxide levels in 14-day-old male broilers in comparison to all the other in ovo injection treatment groups. Compared to a commercial diet, dietary L-AA lowered feed conversion ratio during the second week of post hatch growth. In conclusion, the in ovo administration of L-AA was more effective in reducing inflammatory response, whereas the dietary source had a greater impact on the live performance of broilers. Further research is needed to determine the aforementioned effects throughout the entire growing phase.Effects of the dietary and in ovo administration of L-ascorbic acid (L-AA) on the performance, plasma nitric oxide, and eye L-AA concentrations of Ross 708 broilers were investigated. At 17 days of incubation, live embryonated hatching eggs were randomly assigned to a non-injected or sham-injected (100 μL of saline) control group, or a group injected with either 12 or 25 mg of L-AA suspended in 100 μL of saline. Chicks received a commercial diet with or without 200 mg/kg of supplemental L-AA and were randomly assigned to each of 6 replicate floor pens in each in ovo injection-dietary treatment combination. Weekly live performance variables through 14 days of post hatch age (doa) and the eye weights in both sexes at 0, 7, and 14 doa were determined. At 0 and 14 doa, plasma nitric oxide levels and eye L-AA concentrations of one bird of each sex in each pen were determined. Dietary supplemental L-AA decreased feed intake and growth between 0 and 7 doa, but from 8 to 14 doa; all birds fed supplemental L-AA had a lower feed conversion ratio. At 14 doa, male chicks had higher eye L-AA concentrations and lower plasma nitric oxide levels when treated in ovo with 12 mg of L-AA. In conclusion, dietary L-AA may be used to improve feed conversion in the second week of broiler post hatch growth. However, the in ovo administration of 12 mg of L-AA can increase male eye L-AA concentrations and is effective in reducing their general inflammatory response.

Selective Visualization of Live Intestinal Parasites in Stool Specimens Without Purification.

Microscopic observation of live parasites in the stool is an important diagnostic tool in human and veterinary medicine. Because of the presence of large amounts of contaminating organic matter, microscopic analysis must be preceded by time-consuming pre-purification steps. Transmission-through-dye (TTD) optical microscopy obviates this problem. The purpose of this study is to illustrate the use of TTD for the analysis of stool samples. TTD imaging is based on the exclusion of a strongly absorbing dye by living cells. A food colorant Acid Blue 9 (AB9) is added to a fecal suspension, and the sample is observed under transmitted illumination through a 630 nm bandpass filter. AB9 strongly absorbs red light, and it comes out of the sample significantly attenuated. However, if a viable cell of any origin is present in the sample, it excludes the dye and reduces the depth of the light-absorbing layer. Live cells or eggs appear bright red on a dark background, while most of the organic contaminants remain dark. The method has been demonstrated on schistosomes, hookworms, giardia, yeast, and other organisms. TTD dramatically increases the visibility of live parasites and permits their direct observation in a fecal suspension. TTD can be enabled on any microscope by simply adding a red filter.

The oocyte spindle midzone pauses Cdk1 inactivation during fertilization to enable male pronuclear formation and embryo development.

Inactivation of cyclin-dependent kinase 1 (Cdk1), controlled by cyclin B1 proteolysis, orders events during mitotic exit. Here, we used a FRET biosensor to study Cdk1 activity while simultaneously monitoring anaphase II and pronuclear (PN) formation in live mouse eggs throughout fertilization. We find that Cdk1 inactivation occurs over two phases separated by a 3-h pause, the first induces anaphase II and the second induces PN formation. Although both phases require the inhibitory Cdk1 kinase Wee1B, only the first involves cyclin B1 proteolysis. Enforcing the 3-h pause is critical for providing the delay required for male PN formation and is mediated by spindle midzone-dependent sequestration of Wee1B between the first and second phases. Thus, unlike continuous Cdk1 inactivation driven by cyclin B1 proteolysis during mitotic exit, MII oocytes engineer a physiologically important pause during fertilization involving two different pathways to inactivate Cdk1, only the first of which requires proteolysis.

Effects of the In Ovo Injection of L-Ascorbic Acid on Broiler Hatching Performance.

Simple SummaryPrevious studies have shown positive effects of the use of supplementary L-ascorbic acid (L-AA) to mitigate various stressors such as heat and ammonia exposure in the broiler industry. The aim of the current study was to determine the effects of L-AA administrated by in ovo injection on various hatch variables and the embryonic serum L-AA concentrations of Ross 708 broilers. At 18 days of incubation (doi), the following four treatment groups: non-injected control, saline-injected control, and saline containing either 12 or 25 mg of L-AA were administrated. An automated multi-egg injector accurately delivered 100 μL solution volumes into the amnion. The in ovo injection of high levels of L-AA (12 and 25 mg) did not affect hatchability, but 12 mg of L-AA in saline and saline alone resulted in a reduction in embryonic mortality. Additionally, serum L-AA did not differ between the in ovo injected treatments at any time period; however, the serum L-AA concentration was numerically higher in males as compared to female hatchlings. In conclusion, the automated in ovo injection of high levels of L-AA may not be detrimental to hatchling quality but may promote embryonic livability.Effects of the in ovo injection of various concentrations of L-ascorbic acid (L-AA) on the hatchability and retention levels of L-AA in the serum of broiler embryos were investigated. A total of 960 Ross 708 broilers hatching eggs were randomly divided into four treatment groups: non-injected control, saline-injected control, and saline containing either 12 or 25 mg of L-AA. At 18 days of incubation (doi), injected eggs received a 100 μL volume of sterile saline (0.85%) alone or containing one of the two L-AA levels. Percentage egg weight loss was also determined from 0 to 12 and 12 to 18 doi. Hatch residue analysis was conducted after candling to determine the staging of embryo mortality. At approximately 21 doi, hatchability of live embryonated eggs (HI) and hatchling body weight (BW) were determined. Blood samples were taken at 6 and 24 h after L-AA in ovo injection to determine serum L-AA concentrations. Serum L-AA concentrations, HI, and hatchling BW did not differ among all treatment groups. However, chicks in the non-injected group had a higher (p = 0.05) embryonic mortality at hatch in comparison to those in the 12 mg of L-AA in saline and saline alone treatment groups. These results suggest that the in ovo injection of high levels of L-AA (12 and 25 mg) does not negatively affect HI or serum concentrations of L-AA but has the potential to promote embryonic livability. Further research is needed to determine the retention time of L-AA in the other tissues of broilers, including the cornea of the eye, in response to different levels of supplemental L-AA.

Effects of formalin preservation on egg size of small pelagic fish as major target species in ichthyoplankton surveys

AbstractPreservation is critical for egg and larval samples from ichthyoplankton surveys. As growing interest is directed toward maternal effects on egg quality, historical collections of egg samples in formalin are potentially invaluable materials but concerns about the effects of formalin preservation need to be clarified. The present study examined effects of formalin preservation on egg size of Japanese sardine Sardinops melanostictus, chub mackerel Scomber japonicus and Japanese anchovy Engraulis japonicus over a long period (30–36 months). Overall, the egg sizes slightly decreased in a couple of months after preservation but then recovered to be at a similar level to the live eggs for diameters of spherical eggs of sardine and mackerel and short diameters of ellipsoidal eggs of anchovy, although a caveat lies in unstable and slightly increasing patterns in long diameters of anchovy eggs. No substantial differences were found between 5% and 10% formalin solutions. For practical purposes, we conclude that no correction factors are required for using the measurements of egg samples preserved in formalin over a long period. Assuming the applicability to congeneric species, the information presented here supports the validity of previous studies and will promote future studies on egg size variability in small pelagic fish based on historical collections of egg samples preserved in formalin in various regions of the world.