High Fecundity Rate Research Articles

Ecotoxicological studies of direct and indirect genotoxicity with Artemia: a integrative review

Artemia is a brine shrimp genus adapted to extreme habitats like ranges salinity from 5–25 g/L and in temperatures from 9 to 35 °C. It is widely distributed and used as an environmental quality biomarker. Artemia franciscana and Artemia salina species are commonly used in ecotoxicological studies and genotoxicity assays due to their short life cycle, high fecundity rate, easy culture, and availability. Thus, considering the importance of these tests in ecotoxicological studies, the present study aimed to present Artemia genus as a biological model in genotoxicity research. To this end, we reviewed the literature, analyzing data published until July 2023 in the Web of Science, SCOPUS, Embase, and PubMed databases. After screening, we selected 34 studies in which the genotoxicity of Artemia for various substances. This review presents the variability of the experimental planning of assays and biomarkers in genotoxicity using Artemia genus as a biological model for ecotoxicological studies and show the possibility of monitoring biochemical alterations and genetic damage effects. Also highlight innovative technologies such as transcriptomic and metabolomic analysis, as well as studies over successive generations to identify changes in DNA and consequently in gene expression.

Analysis of Elimination Effects of Inbreeding on Genotype Frequency in Larval Stages of Chinese Shrimp.

Marine animals possess genomes of considerable complexity and heterozygosity. Their unique reproductive system, characterized by high fecundity and substantial early mortality rates, increases the risk of inbreeding, potentially leading to severe inbreeding depression during various larval developmental stages. In this study, we established a set of inbred families of Fenneropenaeus chinensis, with an inbreeding coefficient of 0.25, and investigated elimination patterns and the manifestations of inbreeding depression during major larval developmental stages. Reduced-representation genome sequencing was utilized to explore the genotype frequency characteristics across two typical elimination stages. The results revealed notable mortality in hatching and metamorphosis into mysis and post-larvae stages. Inbreeding depression was also evident during these developmental stages, with depression rates of 24.36%, 29.23%, and 45.28%. Segregation analysis of SNPs indicated an important role of gametic selection before hatching, accounting for 45.95% of deviation in the zoea stage. During the zygotic selection phase of larval development, homozygote deficiency and heterozygote excess were the main selection types. Summation of the two types explained 82.31% and 89.91% of zygotic selection in the mysis and post-larvae stage, respectively. The overall distortion ratio decreased from 22.37% to 12.86% in the late developmental stage. A total of 783 loci were identified through selective sweep analysis. We also found the types of distortion at the same locus could change after the post-larvae stage. The predominant shifts included a transition of gametic selection toward normal segregation and other forms of distortion to heterozygous excess. This may be attributed to high-intensity selection on deleterious alleles and genetic hitchhiking effects. Following larval elimination, a greater proportion of heterozygous individuals were preserved. We detected an increase in genetic diversity parameters such as expected heterozygosity, observed heterozygosity, and polymorphic information content in the post-larvae stage. These findings suggest the presence of numerous recessive deleterious alleles and their linkage and suggest a major role of the partial dominance hypothesis. The results provide valuable insights into the mechanisms of inbreeding depression in marine animals and offer guidance for formulating breeding strategies in shrimp populations.

A Review on Digestive System of Rhynchophorus ferrugineus as Potential Target to Develop Control Strategies

Rhynchophorus ferrugineus, commonly known as red palm weevil (RPW), is a high-risk insect pest that has become a threat to many important palm species. There are several dominant factors that lead to the successful infestation of RPW, including its stealthy lifestyle, highly chitinized mouthpart, and high fecundity rate. Due to that, millions of dollars of losses have been suffered by many countries invaded by RPW. Several methods have been designed to control its invasion, including the usage of insecticides, but many cause resistance and environmental pollution. Therefore, an environmentally friendly insecticide that targets specific systems or pathways in RPW is urgently needed. One of the potential targets is the digestive system of RPW, as it is the major interface between the insect and its plant host. The related knowledge of RPW’s digestive system, such as the anatomy, microflora, transcriptomic analysis, and proteomic analysis, is important to understand its effects on RPW’s survival. Several data from different omics regarding the digestive systems of RPW have been published in separate reports. Some of the potential targets have been reported to be inhibited by certain potential insecticides, while other targets have not yet been tested with any inhibitors. Hence, this review may lead to a better understanding on managing infestations of RPW using the system biology approach for its digestive system.

Effect of Nutritional Flushing Using Long-Term Energy and Protein Supplementation on Growth Performance and Reproductive Parameters of Doyogena Ewes in Ethiopia.

The objective of the study was to establish the effect of appropriate supplementation days (days -21 to +7) using four isonitrogenous (14.7% CP) diets balanced to provide low (Lo-ME) or high (Hi-ME) metabolizable energy on the body condition score (BCS), body weight (BW) change, and reproductive performances of sheep. Thirty-five Doyogena ewes (27.71 ± 2.87 kg, 2-5 years of age, BCS of 2.0-2.5) grazing on natural pasture were randomly assigned to supplementary treatments consisting of combinations of enset leaf (EL) and commercial concentrate (CC): T0 (control), T1 (250 g EL + 500 g CC: Lo-ME), T2 (400 g EL + 500 g CC; Hi-ME), T3 (500 g EL + 400 g CC; Hi-ME), and T4 (500 g EL + 250 g CC; Lo-ME). The estrous cycle was synchronized with one intramuscular injection, 5 mg PGF2α, prior to artificial insemination. The dry matter (DM) from the pasture provided 1.10-1.46 kg/day, which corresponds to the DM requirements of the ewes until late gestation. However, the pasture provided a protein content of 9.52%, which was insufficient for breeding, mid-gestation, and gestation, requiring minimums of 16.1%, 13.1%, and 14.8%, respectively. The pasture could only provide enough energy for breeding ewes with a BW of up to 30 kg. The energy provided by pasture was insufficient for ewes weighing > 30 kg at mid-gestation and gestation, providing 6.9-9.2 MJ/day, below the requirement of 11.92-16.32 MJ/day required for mid-gestation and gestation. The energy was not sufficient for large ewes weighing > 40 kg. Supplementary diets T1-T4 provided DM in the range of 1.7-2.29 kg/day. This was sufficient for AI, mid-gestation, and gestation phases. Dietary supplements increased (p < 0.01) BW during breeding and mid-gestation. During lambing, T2 and T3 increased BW (p < 0.05) compared to T4 and T1. T4 had a similar effect (p > 0.05) on BW during lambing. T1, T2, and T3 significantly increased BCS (p < 0.05). T2 and T3 increased (p < 0.05) BCS at mid-gestation, but only T2 significantly increased BCD (p < 0.05) during lambing. All dietary supplements resulted in a shorter (p < 0.05) time to the resumption of estrous and the length of estrous (p < 0.05). T1, T2, and T3 resulted in a stronger estrous response (p < 0.05). Dietary supplements enhanced (p < 0.05) the conception rate and fecundity rate. The conception rate was highest in T2 and T3 at 85.7% and 83.3%, respectively. T2 had the highest fecundity rate at 151.7% (p < 0.05). Dietary supplementation increased the rate of lambing (LR), litter size (LS), and weight of lambs at birth (LBW). The LR for treatments T2, T3, and T4 was 100% versus 66.7% in the control. T1 and T2 significantly increased (p < 0.05) LS, but T4 had a similar LS to the control. Dietary supplements T1, T3, and T4 tended to increase (p < 0.05) LBW, but T2 increased LBW significantly (p < 0.05). Supplementation (T2, T3) with 400 g enset + 500 g CC and 500 g enset + 400 g CC are promising feed supplements to increase the reproductive capacities of Doyogena ewes in Ethiopia. Energy is as important to ewe flushing as protein.

On the road to self-sustainability: reintroduced migratory European northern bald ibises Geronticus eremita still need management interventions for population viability

AbstractThe northern bald ibis Geronticus eremita disappeared from Europe in the Middle Ages. Since 2003 a migratory population has been reintroduced in Central Europe. We conducted demographic analyses of the survival and reproduction of 384 northern bald ibises over a period of 12 years (2008–2019). These data also formed the basis for a population viability analysis simulating the possible future development of the northern bald ibis population under different scenarios. We analysed life stage-specific survival rates, rearing protocols and colonies, and the influence of stochastic catastrophic events and reinforcement translocations on population growth. Life stage-specific survival probabilities were 0.64–0.78. Forty-five per cent of the mature females reproduced, with a mean fecundity of 2.15 fledglings per nest. The complementary population viability analysis indicated that the Waldrappteam population is close to self-sustainability, with an estimated population growth rate of 0.95 and a 24% extinction probability within 50 years. Of the 326 future scenarios tested, 94% reached the criteria of extinction probabilities &lt; 5% and population growth rates &gt; 1. Stochastic catastrophic events had only a limited effect. Despite comparatively high survival and fecundity rates the population viability analysis indicated that to achieve self-sustainability the Waldrappteam population needs further translocations to support population growth and the implementation of effective measures against major mortality threats: illegal hunting in Italy and electrocution on unsecured power poles. The findings of this study are to be implemented as part of a second European LIFE project.

Biology of green apple aphid, Aphis pomi De Geer on high density apple plantations in Kashmir province of J&amp;K UT, India

As Aphis pomi is one of the important and emerging pest especially on apple plants from past few years as its huge incidence has attracted the attention of research workers across the globe especially in apple growing regions. Currently the most important constraint for apple producers is that its management becomes difficult due to resurgence problems and also their high fecundity rate, complex life cycle. So our motive to study biology of Aphis pomi is to find a better management strategy as biological study of insect is one of the key factor for its management. In the present study the biological parameters evaluated were duration and survival% of nymphal instars, daily and total fecundity and adult longevity by various methods under laboratory conditions. Also the data on pre-oviposition, oviposition and post-oviposition was recorded. We found that duration of total nymphal period, pre-ovipositional period, ovipositional period, post ovipositional period and total life period varied from 13.5-15.5 (14.52±0.070), 10.3-12.5 (14.52±0.07), 10- 20 (13.4±0.65), 2.0-3.0 (2.4±0.17), and 22-35 (30.28±1.51) days respectively. The morphometric were also studied during the period of nymphal development till adults. The morphometric analysis showed gradual developmental variations from first instar to adult stage in size, shape, colour and number of characters.

Biologi ngengat Galleria mellonella (Linn.) (Lepidoptera: Pyralidae) pada beberapa jenis pakan buatan

Ngengat lilin (Galleria mellonella (Linnaeus)) merupakan salah satu hama penting pada peternakan lebah madu di Asia. Selain sebagai hama, G. mellonella ternyata juga digunakan sebagai serangga uji di beberapa bidang usaha. Kebutuhan populasi G. mellonella mendorong beberapa bidang usaha untuk membudidayakannya secara praktis dan ekonomis. Penelitian ini bertujuan mengetahui dan menguji komposisi bahan makanan sebagai pakan buatan yang dapat memengaruhi pertumbuhan dan perkembangan G. mellonella. Pengujian terdiri atas empat formula modifikasi pakan yang berbeda, yaitu P1 (tepung jagung, dedak gandum, gliserol, dan ragi), P2 (tepung beras, tepung terigu, dedak gandum, gliserol, dan ragi), P3 (tepung terigu, dedak gandum, gliserol, dan ragi), dan P4 (beras merah, gliserol, dan ragi). Kriteria pengamatan yang dilakukan, yaitu siklus hidup, tingkat mortalitas, fekunditas, dan fertilitas telur ngengat G. mellonella. Berdasarkan hasil penelitian, perkembangan siklus hidup G. mellonella terpendek pada perlakuan P3 (71,5 ± 5,2 hari), sedangkan perlakuan P4 terpanjang (84,2 ± 8,3 hari). Tingkat mortalitas tertinggi pada tipe pakan P3 sebesar 13,12%, sedangkan terendah terjadi pada perlakuan P4 sebesar 4,44%. Berdasarkan fekunditas imago betina, perlakuan P4 memiliki tingkat fekunditas tertinggi, yaitu sebesar 527,7 telur/betina, sedangkan perlakuan P1 merupakan yang terendah (169,6 telur/betina). Perlakuan P4 memberikan respons terbaik pada beberapa aspek biologi ngengat G. mellonella, seperti ukuran tubuh yang lebih besar, mortalitas yang lebih rendah, dan tingkat fekunditas yang tinggi.

Effects of abiotic factors on the immature development, adult performance, and field parasitism of mass-reared Anastatus parasitoids (Hymenoptera: Eupelmidae)

ABSTRACT Anastatus japonicus Ashmead, A. fulloi Sheng, and Wang, and A. dexingensis Sheng and Wang are vital biocontrol agents for the univoltine litchi stink bug Tessaratoma papillosa (Drury) in Taiwan as well as other invasive hemipteran and lepidopteran pests worldwide. An effective augmentative biocontrol programme was established with Anastatus parasitoids produced using eggs of the ailanthus silkmoth (Samia cynthia (Drury)) as factitious hosts. The study’s objective was to evaluate the immature development and adult performance of three Anastatus parasitoid species at 20, 25, and 30°C. The highest numbers of female and total progeny were produced by A. japonicus at 25°C and by A. dexingensis and A. fulloi at 20°C and 30°C, respectively. Anastatus japonicus had higher parasitism rates than A. dexingensis and A. fulloi at all three temperatures. The female ratios increased from 24.9% at 20°C to 70.4% at 30°C. The highest female ratios were recorded during the first two weeks of reproduction, and male progeny’s proportion gradually increased with female age. Anastatus japonicus was selected as the biocontrol agent for mass production based on its high fecundity and female progeny production rates. The field parasitism from the three release sites showed 30–40% of field parasitism during the first nine days of release. A significant reduction of field parasitism occurred after rainfall. The A. japonicus production system developed herein using the eggs of the factitious ailanthus silkmoth host could be commercialised to provide biocontrol against other hemipteran and lepidopteran pests species.

Experimental infection with Schistosoma mansoni isolated from the wild rodent Holochilus sciureus shows a low parasite burden but induces high schistosomiasis severity in BALB/c mice.

Wild mammals, especially rodents, can participate in the life cycle of Schistosoma mansoni; however, the impact of these parasite strains on the severity of schistosomiasis remains unclear. The aim of this study was to comparatively evaluate the parasitological and immunopathological alterations induced by an S. mansoni strain isolated from the wild rodent Holochilus sciureus (HS strain) and a parasite strain isolated from a human (LE strain) in experimentally infected mice. Male BALB/c mice were subcutaneously infected with 50 cercariae/mouse of either the HS or the LE strain and were evaluated for 12 weeks. In the experimental groups, the parasite burden was estimated by worm and egg (feces and tissues) count, and immunopathological alterations were evaluated in the liver and intestines. Compared to experimental infection with the LE parasite strain, HS-infected mice showed reduced number of parasite worms but higher fecundity rate, significant reduction in IL-5, IL-10 and IL-13 concentrations, lower EPO-activity in liver homogenate and higher concentrations of TNF-α, IFN-γ, IL-12 and IL-17 in the small intestine homogenate. Moreover, HS infection resulted in higher concentrations of NO end-products in both the liver and intestine, suggesting a predominance of the Th1/Th17 immune response. HS-infected mice also showed higher plasma transaminase levels, formed larger granulomas, and had a higher mortality rate in comparison with LE-infected mice. Data indicate that BALB/c mice infected with the HS strain of S. mansoni showed reduced susceptibility to the parasite but stronger tissue inflammation and high disease severity.

Making a meal out of bugs

Making a meal out of bugs

Interaction between biological parameters of Panonychus citri (Acari: Tetranychidae) and some phytochemical metabolites in different citrus species.

The citrus red mite, Panonychus citri McGregor, is a key pest of different citrus species in various parts of the world. Considering the key role of resistant host plants in integrated pest management strategies, we evaluated the effects of five citrus species including grapefruit (Citrus paradisi), lime (Citrus aurantifolia), tangerine (Citrus reticulata), orange (Citrus sinensis), and sour orange (Citrus aurantium) on life table parameters of P. citri under laboratory conditions (25 ± 1°C, 65 ± 5% RH, 16:8 L:D). In addition, biochemical traits of the citrus plant species were evaluated in order to understand any possible relationship between important life history parameters with biochemical metabolites of citrus plant leaves. Phytochemicals were determined in leaf extract of citrus plant species. Various citrus species had significant effects on life history and demographical parameters of P. citri. The longest pre-adult time was observed on grapefruit (16.52 ± 0.43 days). Higher fecundity rate was on orange (15.05 ± 2.41 eggs) and tangerine (14.60 ± 3.07 eggs) and the lowest was on grapefruit (7.21 ± 2.00 eggs). The highest intrinsic rate of increase (r) was recorded as 0.071 (day-1) on tangerine, and the lowest value of this parameter was obtained on grapefruit (0.016 day-1). Significant correlations were observed between life history parameters with biochemical metabolites (carbohydrate, phenolic compounds, anthocyanin, and flavonoid). The results revealed that grapefruit was a relatively resistant host plant and tangerine was the most suitable host plant for feeding of P. citri. Our findings could be helpful for sustainable management of P. citri in citrus orchards.

Wild pig removal reduces pathogenic bacteria in low-order streams

Invasive wild pig populations have undergone enormous increases in the United States and particularly across the southern U.S. in recent years. High fecundity rates and abilities to adapt quickly to varied habitats have enabled pig populations to become entrenched and difficult to eliminate. The pigs cause many negative impacts on ecosystems including degradation of water quality through infusion of fecal contamination and other non-point source pollutants. Our goal was to determine the effects of pig removal on water quality in streams that were known to be significantly polluted by pig activity Bolds (J Environ Qual 50: 441–453, 2021). We compared e. coli and fecal coliform concentrations and loads in streams between a pre-removal period with those that occurred during the removal activities. Results suggest that e. coli and fecal coliform concentrations were reduced by 75 and 50% respectively through pig removal efforts. Questions remain concerning the longevity of the reduction especially once pig removal activities decrease in intensity.

Evaluation of the effectiveness of Neoseiulus cucumeris (Oudemans) as a predator of Tuta absoluta (Meyrick).

The leaf miner, Tuta absoluta is continue to be a serious threat to solanaceous plants, especially tomato plant worldwide. Tomato crop in Saudi Arabia has been recently affected by T. absoluta, which is difficult to control due to its unique biological features, such as high fecundity and its potential to develop resistance to chemical pesticides. In this article, the suitability and effectiveness of the predatory mite, Neoseiulus cucumeris (Oudemans) (Acari: Phytoseiidae), an indigenous species usually found in tomato greenhouses of northcentral Saudi Arabia, has been evaluated on eggs and 1st instar larvae of T. absoluta in the laboratory. All experiments were conducted in an incubator at three constant temperatures of 22, 27 and 32°C ± 1°C, 50 ± 4% R.H. and L12:D12 h photoperiod. Adult females and males of N. cucumeris were able to feed and sustain oviposition on eggs and 1st instar larvae of T. absoluta, and could be an effective biocontrol agent against T. absoluta. The N. cucumeris had a clear preference for eggs compared to 1st instar larvae of T. absoluta. The results showed the obvious effect of the temperature on the consumption rate of the predatory mite. The maximum daily consumption rate occurred during the oviposition period, when the females of the predatory mite consumed an average of 4.26 eggs and 2.44 1st instar larvae of T. absoluta. In general, total fecundity was high with T. absoluta eggs as a food source when temperature increased from 22 to 32°C. The highest fecundity rate (42.92 and 20.97 eggs /female) was recorded at 32°C, while the lowest one (26.77 and 10.12 eggs / female) was recorded at 22°C, when N. cucumeris female fed on eggs and 1st instar larvae of T. absoluta, respectively. The results of this study indicated that the predatory mite, N. cucumeris can be considered a promising potential candidate for controlling the leaf miner T. absoluta, and further research is required to assess its effectiveness under greenhouse conditions.

Spatial distribution and factors associated with modern contraceptive use among women of reproductive age in Nigeria: A multilevel analysis.

BackgroundEvidence suggests that in countries with high fertility and fecundity rates, such as Nigeria, the promotion of modern contraceptive use prevents approximately 32% and 10% of maternal and child mortality, respectively. Therefore, this study aimed to assess the spatial distribution of modern contraceptive use and its predictors among women of reproductive age in Nigeria.MethodsThe study employed a cross-sectional analysis of population-based data involving 24,281 women of reproductive age in Nigeria. The study adopted both multilevel and spatial analyses to identify the predictors of modern contraceptive use and its spatial clustering among women in Nigeria.ResultsModern contraceptive use among the study population in Nigeria ranged from 0% to 75%, with regional variations. The spatial analysis showed that areas with a low proportion of modern contraceptive use were Sokoto, Yobe, Borno, Katsina, Zamfara, Kebbi, Niger, Taraba and Delta. Areas with a high proportion of modern contraceptive use were Lagos, Oyo, Osun, Ekiti, Federal capital territory, Plateau, Adamawa, Imo, and Bayelsa. The multilevel analysis revealed that at the individual level, women with secondary/higher education, women from the Yoruba ethnic group, those who had four children and above, and those exposed to mass media had higher odds of using modern contraceptives. On the other hand, women who were 35 years and above, those who were married, and women who were practicing Islam were less likely to use modern contraceptives. At the household/community level, women from the richest households, those residing in communities with medium knowledge of modern contraceptive methods, and women residing in communities with a high literacy level were more likely to use modern contraceptives.ConclusionThere were major variations in the use of modern contraception across various regions in Nigeria. As a result, areas with low contraceptive rates should be given the most deserving attention by promoting contraceptive education and use as well as considering significant factors at the individual and household/community levels.

Natural history of neustonic animals in the Sargasso Sea: reproduction, predation, and behavior of Glaucus atlanticus, Velella velella, and Janthina spp.

The Sargasso Sea, located in the North Atlantic subtropical gyre, is one of the most well-known ocean surface ecosystems on the planet. It supports numerous ecologically and economically important fish species, juvenile turtles, and endemic species. However, in addition to the floating algae Sargassum from which the sea derives its name, numerous floating neustonic animals also live at the surface, yet their basic natural history remains poorly known. Without the basic knowledge of these species, understanding ecosystem function, food webs, and pollution impacts is impossible. This is especially problematic because pollutants like plastic are now increasing at the surface at alarming rates. This study examines the diet, reproduction, and behavior of four neustonic animal species: Velella velella, Janthina janthina, Janthina pallida, and Glaucus atlanticus. All mollusk species showed unique predatory preferences and behaviors, indicating possible methods of niche partitioning among these species. For example, Glaucus atlanticus showed an equal preference for all prey but preyed primarily by crawling below to consume the underside of prey, while large J. janthina often preyed more on the margin of V. velella and P. physalis, in contrast, J. pallida only preyed on V. velella. Of the four species observed, two reproduced in the lab (G. atlanticus and V. velella), and the embryo cases of J. pallida were examined from both collected snails and discarded bubble rafts. High fecundity rates were observed in all species, which may be an adaptation to high loss rates. This study lays the groundwork for future research on neustonic animals in the Sargasso Sea.

Neoseiulus californicus (Acari: Phytoseiidae) shows good predation potential when reared on an artificial diet supplemented with Tetranychus cinnabarinus

To evaluate the predation potential of Neoseiulus californicus (McGregor) reared on an artificial diet as a biological control agent for Tetranychus cinnabarinus (Boisduval), life table and functional response studies were performed. To identify alternative food sources for rearing N. californicus, we compared the nutritional values of the basal diet (composed of sucrose, yeast extract, honey, tryptone and egg yolk), meridic diet (add T. cinnabarinus on the basis of basal diet) and control (T. cinnabarinus). Further, the predation ability of N. californicus continuously reared for ten consecutive generations on a meridic diet to control T. cinnabarinus was assessed. The results showed that N. californicus fed the basal and meridic diets successfully completed development from eggs to adults, but they did not oviposit when fed the basal diet. The high fecundity (41.00 eggs per female) and intrinsic rate of increase (0.2357 d-1) recorded in the meridic diet group suggests that it is a suitable diet for N. californicus rearing. Additionally, a functional response (type II) was observed in N. californicus reared on the meridic diet. We found that when the predator was reared on the meridic diet, the estimated maximum attack rate (T/Th) associated with larvae was 58.67, which was only 13.94% lower than the control (68.17). The 10th generation of N. californicus did not lose the ability to capture and kill T. cinnabarinus when fed on meridic diet. In conclusion, N. californicus reared on the meridic diet containing T. cinnabarinus showed good predation ability; therefore, this diet may be beneficial for the mass production of N. californicus.

Invasive Sun Coral Species Challenges Decommissioning of Structures Offshore Brazil

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper OTC 30656, “Decommissioning of Subsea Structures in Brazil: Effect of Invasive Species and Genome Sequence of the Azooxanthellate Coral Tubastraea sp.,” by João Humberto Guandalini Batista, SPE, Repsol; Mauro Rebelo, Universidade Federal do Rio de Janeiro; and Giordano Soares-Souza, SENAI CETIQT, prepared for the 2020 Offshore Technology Conference, originally scheduled to be held in Houston, 4–7 May. The paper has not been peer reviewed. Copyright 2020 Offshore Technology Conference. Reproduced by permission. Decommissioning of offshore assets in Brazil is subject to high levels of uncertainty because of Tubastraea, an invasive species of sun coral. This species has a high capacity for dispersion and recruitment and has been associated with the replacement of native species in rocky shores, exerting a serious effect on native biodiversity. The complete paper explores the biology of the invasive species, aiming to identify methods to eliminate or diminish its spread. The authors write that data generated in this study will foster the development of effective technologies in coral-species management, whether species are invasive or threatened. Introduction Originally from the Coral Triangle in the Pacific Ocean—a highly diverse region with hundreds of coral species—Tubastraea was first observed in the Campos Basin in the 1980s. Tubastraea sp. have high fecundity and growth rates with the ability to reproduce asexually, establishing very dense populations. This fast reproduction allows larvae to outcompete native species in both natural and artificial substrates in the sea. Sun coral is extremely resistant to environmental change. It has been found in shallow waters, sometimes exposed to air, showing tolerance even to short periods of desiccation. Recently, new species have been identified in Brazilian waters, heightening concern over the proliferation of sun coral. In the past, the common understanding was that subspecies coccinea and tagusensis were those found in Brazilian waters. However, recent studies dedicated to the research of the Tubastraea genus raised suspicion of the presence of diaphana and aurea, with the possible occurrence of hybrids as well. The preference of Tubastraea is to live in structures that are static or mostly motionless, such as production platforms, subsea structures, and drilling rigs. This trait has made sun coral a major challenge for the local oil and gas industry. While in the Campos Basin, the main objective is to decrease dispersion of already bioencrusted production units and subsea structures, in the Santos Basin, the goal is to avoid colonization in structures in operation or those scheduled to be installed soon. To further complicate matters, drilling and intervention vessels and rigs are contracted to service both basins. They work in dynamic-positioning mode, stationary around the production units and subsea structures for lengths of time that exceed the reproduction cycle time of the sun coral, allowing larval dispersion.

A review on biological interactions and management of the cotton bollworm,Helicoverpa armigera(Lepidoptera: Noctuidae)

AbstractHelicoverpa armigeraHübner (Lepidoptera: Noctuidae) is one of the most damaging insect pests globally, causing estimated global economic losses of over 3 billion US dollars annually. Crops most affected include cotton, tomato, soybean, grain crops such as corn and sorghum, chickpea and other pulses. Adults of this species possess strong migratory abilities (&gt;2000 km), high fecundity and rapid reproductive rates; completing 4–6 generations per year in most cropping regions. Furthermore, the larvae are polyphagous, with a wide and diverse host range and possess the ability to enter diapause in order to survive adverse climatic conditions. At present, it is distributed across most of Oceania, Asia, Africa and southern Europe and has recently spread to South America. Various control measures have been trialled or proposed for the treatment of this pest, including synthetic insecticides, phytopesticides, microbial pesticides, macro‐biocontrol agents (both parasitoids and predators) and the development of genetically modified crops (e.g.Btcotton). Successful control necessitates the use of an integrated pest management (IPM) approach, wherein biological, chemical and physical control measures are combined for the greatest control efficacy.

Localization, Distribution and Structure of Muscle Fibres Using Specific Antibody Markers in the zebrafish, Danio rerio (Hamilton, 1822)

The zebrafish Danio rerio is a popular model species for genetic and early development studies. It is relatively easy to maintain in laboratory, has a high fecundity rate and produces transparent embryos. Here, we characterise muscle development in early life stage zebrafish using paraffin sections of embryos and larvae treated with haematoxylin and eosin staining, and whole mount fluorescent immunohistochemistry. We found variations in the distribution of muscle mass throughout the body, with the greatest proportion of muscle mass found in the tail. Our data also showed for the first time the reaction of antibodies (protein expression) in muscle at early life stages of development. Whole mount fluorescent immunohistochemistry staining with three markers (PAX7, MF20 and F59) suggests that muscle development starts even earlier than previously suggested at the embryonic stage (1 dpf).

Reproductive biology of the anchovy (Stolephorus commersonnii, Lacepède, 1803) and spotted sardine (Amblygaster sirm, Walbaum, 1792) from Tanga Region, Tanzania

The present study investigated the reproductive biology of Stolephorus commersonnii and Amblygaster sirm at two landing sites in Tanga on the northern coast of Tanzania. Fish samples were collected on a monthly basis from ringnets operated by artisanal fishers in the nearby coastal waters. Spawning seasons were determined using gonadosomatic index (GSI) and gonadal maturity stages. The size at first maturity was 57.7 mm and 66.2 mm total length for male and female S. commersonnii respectively. Male and female A. sirm were estimated to attain first maturity at 147.7 mm and 169.2 mm respectively. The spawning seasons of both species were protracted. S. commersonnii demonstrated a year round spawning cycle with peaks in August, October and January. The peak spawning season for male and female A. sirm was recorded in August and September respectively. Both species exhibited skewed size-dependent sex ratios with females predominating in the larger size classes. A. sirm had a higher fecundity rate with a maximum of 96,500 eggs in the largest female fish of 258 mm as compared to S. commersonnii (10,055 eggs) in the largest fish of 98 mm. The mean (±SE) total fecundity of S. comersonnii and A. sirm was 5,134.7 ± 136.9 eggs, and 47,029.03 ± 1,435.13 eggs in females of sizes 68 mm to 98 mm and 170 mm to 258 mm respectively.