Experimental Studies on the Life Cycle and Production of the Littoral Oligochaete Lumbricillus lineatus, and Its Response to Oil Pollution

Comprehensive analysis of non-coding RNAs in the ovaries of high and low egg production hens.

The hypothalamic-pituitary-ovarian (HPO) axis regulates the breeding process cycle of laying hens. However, the key regulatory genes of the HPO axis and pathways that drive chicken egg laying performance remain elusive. A total of 856 Chinese Luhua chicken was raised and the highest two hundred and the lowest two hundred chicken egg production were considered as high egg production (HEP) and low egg production (LEP) according to the total egg number at 300 days of age, respectively. RNA-seq sequencing (RNA-Seq) was conducted to explore the chicken transcriptome from the hypothalamus, pituitary gland and ovary tissue of 6 Chinese Luhua chicken with 3 high and low-rate egg production. In total, 76.09 Gb RNA-seq sequences were generated from 15 libraries with an average of 5.07 Gb for each library. Further analysis showed that 414, 356 and 10 differentially expressed genes (DEGs) were identified in pituitary gland, ovary and hypothalamus between HEP and LEP chickens, respectively. In pituitary gland, DEGs were involve in regulation of cellular glucose homeostasis, Ras protein signal transduction, negative regulation of hormone secretion. In Ovary DEGs were mainly involved in embryonic organ development, regulation of canonical Wnt signaling, response to peptide hormone. Our study identified DEGs that regulate mTOR signaling pathway, Jak-STAT signaling pathway, Tryptophan metabolism and PI3K-Akt signaling pathways at HPO-axis in laying hens. These important data contribute to improve our understanding of reproductive biology of chicken and isolating effective molecular markers that can be used for genetic selection in Chinese domestic Luhua chicken.

Comparative transcriptomic analysis of high and low egg-producing duck ovaries

The influence of temperature and salinity on the duration of embryonic development, fecundity and growth of the amphipod Echinogammarus marinus Leach (Gammaridae)

Proteomic analysis of hypothalamic proteins of high and low egg production strains of chickens

[Factors influencing the life history, feeding and reproduction of Cyclops bicuspidatus thomasi and Diaptomus ashlandi in Yellowknife Bay in the Canadian subarctic were studied between August 1975 and November 1976. The former species emerged as copepodid IV from the overwintering stage in June and completed its life cycle in 60 days. Temperature reduced the developmental rate but food supply was not limiting. Although algae were abundant in the environment, <30 cells/animal occurred in the guts of nauplius III to copepodid III. Only the smallest species, Cyclotella glomerata, was usually eaten, with other algae being rejected because of their length. Almost all specimens ingested large quantities of finely divided (<1 μm) detritus. Only 35-55% of carnivorous copepodid IV-VI contained material in their guts. Rotifers were most frequently ingested and copepodid VI fed throughout the reproductive phase. Changing daylength, measured 2 and 4 weeks earlier, accounted for 34 and 68% of variation in the percentage of females with eggs and clutch size respectively. Food supply was second in importance (24-25%) with temperature being of little significance. Variation in the sex ratio could not be adequately explained by daylength, temperature, or food. D. ashlandi required 5 months to complete its life cycle, emerging from the overwintering phase in April as nauplius II. Temperature and possibly photoperiod affected development but food supply was unimportant. Up to 60 algal cells occurred in the gut of copepodid IV-VI with several species (C. glomerata, Synedra acus var. radians, Chrysolykos gracilis, Dinobryon divergens) being ingested. Size selection restricted consumption of most other species. Changing daylength accounted for up to 79% of the variation in the percentage of females with eggs and 67% in the clutch size. Temperature also significantly affected both parameters, with food supply being of little importance. Changes in sex ratio were independent of daylength, food and temperature., Factors influencing the life history, feeding and reproduction of Cyclops bicuspidatus thomasi and Diaptomus ashlandi in Yellowknife Bay in the Canadian subarctic were studied between August 1975 and November 1976. The former species emerged as copepodid IV from the overwintering stage in June and completed its life cycle in 60 days. Temperature reduced the developmental rate but food supply was not limiting. Although algae were abundant in the environment, <30 cells/animal occurred in the guts of nauplius III to copepodid III. Only the smallest species, Cyclotella glomerata, was usually eaten, with other algae being rejected because of their length. Almost all specimens ingested large quantities of finely divided (<1 μm) detritus. Only 35-55% of carnivorous copepodid IV-VI contained material in their guts. Rotifers were most frequently ingested and copepodid VI fed throughout the reproductive phase. Changing daylength, measured 2 and 4 weeks earlier, accounted for 34 and 68% of variation in the percentage of females with eggs and clutch size respectively. Food supply was second in importance (24-25%) with temperature being of little significance. Variation in the sex ratio could not be adequately explained by daylength, temperature, or food. D. ashlandi required 5 months to complete its life cycle, emerging from the overwintering phase in April as nauplius II. Temperature and possibly photoperiod affected development but food supply was unimportant. Up to 60 algal cells occurred in the gut of copepodid IV-VI with several species (C. glomerata, Synedra acus var. radians, Chrysolykos gracilis, Dinobryon divergens) being ingested. Size selection restricted consumption of most other species. Changing daylength accounted for up to 79% of the variation in the percentage of females with eggs and 67% in the clutch size. Temperature also significantly affected both parameters, with food supply being of little importance. Changes in sex ratio were independent of daylength, food and temperature.]

BackgroundWulong geese (Anser cygnoides orientalis) are known for their excellent egg-laying performance. However, they show considerable population differences in egg-laying behavior. This study combined genome-wide selection signal analysis with transcriptome analysis (RNA-seq) to identify the genes related to high egg production in Wulong geese.ResultsA total of 132 selected genomic regions were screened using genome-wide selection signal analysis, and 130 genes related to high egg production were annotated in these regions. These selected genes were enriched in pathways related to egg production, including oocyte meiosis, the estrogen signaling pathway, the oxytocin signaling pathway, and progesterone-mediated oocyte maturation. Furthermore, a total of 890 differentially expressed genes (DEGs), including 340 up-regulated and 550 down-regulated genes, were identified by RNA-seq. Two genes — GCG and FAP — were common to the list of selected genes and DEGs. A non-synonymous single nucleotide polymorphism was identified in an exon of FAP.ConclusionsBased on genome-wide selection signal analysis and transcriptome data, GCG and FAP were identified as candidate genes associated with high egg production in Wulong geese. These findings could promote the breeding of Wulong geese with high egg production abilities and provide a theoretical basis for exploring the mechanisms of reproductive regulation in poultry.

Poultry farming in most countries of the world occupies a leading position among other branches of agricultural production. In recent years, quail breeding has become particularly relevant in Russia and European countries. Intensive growth and development, a short reproduction period, as well as meat and egg productivity, early maturity, high egg production, all this together allows them to be successfully used to obtain high quality products. At the same time, this gives grounds for the competition of quails with chickens for meat and egg productivity. Quail products are recognized as environmentally friendly, easily digestible, a rich source of valuable macro and microelements, as well as a variety of vitamins. In addition, quail eggs are a hypoallergenic product that has tonic properties and contains a large amount of protein. In terms of nutritional properties, quail eggs are healthier than chicken eggs, since they do not contain cholesterol. When growing poultry, no additional costs are required for the prevention of infectious diseases, as well as drugs that accelerate the growth of individuals. Creating optimal microclimate parameters in poultry houses is one of the important conditions for realizing poultry productivity, as well as minimizing the unit costs of material and technical resources. Violation of zoohygienic requirements for keeping quails has a significant impact not only on the productivity of poultry, but also on the health of the personnel working at the factory, as well as on environmental pollution. Microclimate control using an automated system makes it possible to provide optimal conditions for the functioning of the physiological state of individuals, which is reflected in various forms of ethological manifestations, on the reactions of eating behavior.

Life history and population dynamics of an estuarine amphipod, Eriopisa chilkensis Chilton (Gammaridae)

Lately, it has become increasingly clear that global warming has a significant impact on a broad range of organisms, regardless of their ecological and geographical spread. Temperature is one of the most important abiotic factors that determine the spatiotemporal dynamics of structural and functional parameters of populations of Lepidoptera and influencing production and survival of these species of insects in nature. Climate warming has the potential to affect some processes related to the ecology and life cycle of the butterfly, especially directly controlled temperature, such as: gathering the required temperature for a species to reach reproductive maturity, growth initiation and cessation of growth (both processes are conditioned by certain values of temperature, constant for each species). Duration of embryonic development, characteristic of each species, is much influenced by temperature. The development postembryonal is strongly influenced by biotic factors (food), and by the abiotic (temperature, humidity). Temperature variation affects the mobility and life cycle of the butterfly, the effects on metabolic rate (McMillan et. all., 2005). It is believed that Lepidoptera are among the organisms most affected by global warming, which significantly influences their development cycle, reproduction and even survival. Moreover, generations of Lepidoptera are short and reproductive rates are high, so they are likely to respond more quickly to climate change, compared with bodies which have a long cycle life such as plants and vertebrates.

Background. Distribution of root nodule bacteria of soybean in soils of Ukraine is the result of intensive cultivation of soybeans over the last 20 years. During the observation the structure of soybean rhizobia populations for the first time we have determined the strains which significantly differ in phenotypic properties from typical slow-growing bacteria of B. japonicum species previously described. These strains are characterized by high speed growth and we tentatively called them “stains with intensive growth”. The aim of our work was to investigate the genotypic properties of microsymbionts of soybeans with different rates of growth spreading in soils of Ukraine. Materials and methods. The 16S rRNA gene and intergenic 16S-23S rRNA region of six strains - typical representatives of soybean nodule bacteria with slow- and intensive growth-rates was carried out. The strains were picked up from different Ukrainian soils. Results. Analysis of the 16S rRNA nucleotide sequences showed the 100% similarity of slow-growing strains to B. japonicum USDA 6T and USDA 4 ones. This analysis proved propinquity of strains with intensive growth to the strain B. japonicum USDA 127 (USDA 123 group). Representatives of this group possessed increased saprophytic competence so as the examined strains. With use of restriction analysis of ITS intergenic region soybean rhizobia were divided among two ITS types: 1st ITS type - strains with intensive growth, 2nd ITS type - slow- growing strains. According to results of ITS-region sequencing soybean rhizobia form 3 reliably different clusters: two of which include slow-growing strains (group USDA 6 and USDA 4), and a third include soybean microsymbionts with intensive growth (USDA 123 group). Conclusion. On the basis of phenotypic and genotypic (16S rRNA and 16S-23S rRNA) analysis all of the investigated soybean strains of root nodule bacteria were related to the Bradyrhizobium japonicum species. The division of strains by the structure of the ITS-region into two genotypes corresponds to the division of strains into two physiological groups: the strains of an intense and slow growth.

Many fisheries management decisions require predictions of spatial dynamics, and simulation of realistic movement is critically important for accurately representing population‐level dynamics with spatially explicit individual‐based models (IBMs). Movement approaches developed to date have been applied across a wide range of spatiotemporal resolutions. We compared four movement approaches or submodels (restricted‐area search, kinesis, event based, and run and tumble) using an IBM (roughly based on Bay AnchovyAnchoa mitchilliand Northern AnchovyEngraulis mordax) that simulated growth, mortality, and movement of a cohort on a two‐dimensional grid. We evaluated the submodels in 2.7‐ × 2.7‐km environments at five resolutions defined by various cell sizes and time steps. We used a genetic algorithm to calibrate each movement submodel over a 300‐generation training phase and then tested the mean movement parameters for a single generation in the training environment and a novel environment. Restricted‐area search, kinesis, and event‐based submodels had higher egg production than a random walk model (baseline, assuming no behavioral movement) across spatiotemporal resolutions in training and novel environments. The run‐and‐tumble submodel also had higher egg production than the random walk model but only under certain conditions. Although restricted‐area, kinesis, and event‐based submodels outperformed random walk at all resolutions, the submodels did not perform equally well across resolutions in terms of egg production and aggregation of model individuals in high‐quality cells (i.e., those with high growth and low mortality). The variability in performance was due to the change in habitat quality experienced by model individuals from one time step to the next. Restricted‐area and event‐based submodels had higher egg production when model individuals experienced small changes in habitat quality, whereas the kinesis and run‐and‐tumble submodels performed better when model individuals experienced larger changes in habitat quality.Received October 16, 2013; accepted March 11, 2004

SummaryThe life cycle of the cladoceran Simocephalus acutirostratus has been studied in the laboratory with reference to its total life span, duration of instars, egg production and growth. It has four pre‐adult and eighteen adult instars and produces about 248 eggs during a mean life span of 44 days within a temperature range of 28°C‐30°C. Egg production was found to be bimodal, with a sharp decline towards the end of the life cycle. The present results are compared and discussed with those of other tropical and temperate daphnids. It has been shown that while this species resembles most other daphnids (D. middendorffiana, D. pulex, D. carinata) in the growth pattern of pre‐adult instars, it resembles the temperate D. pulex in having a relatively long life span, relatively high egg production and slow rate of growth.While studies on embryonic development of S. acutirostratus resemble the growth stages of the temperate Daphnia magna, there are differences in the total period of development between the two species. In the latter aspect, however, the present species closely resembles other tropical daphnids.

Simple SummaryTranscriptome is the study of gene expression at the RNA level. In this study, high-throughput transcriptome sequencing technology was used to compare and analyze the gene expression differences in the hypothalamus, pituitary, and ovary tissues of Xinjiang Yili geese with high and low egg production. We preliminarily screened 30 candidate genes related to egg production regulation of Xinjiang Yili geese, including the calcium signaling pathway. Therefore, this study laid a theoretical foundation for further elucidating the molecular mechanism of egg production of Yili geese in Xinjiang.The study was conducted to investigate the transcriptomic differences of the hypothalamic-pituitary-gonadal axis between Xinjiang Yili geese with high and low egg production and to find candidate genes regulating the egg production of Xinjiang Yili geese. The 8 selected Xinjiang Yili Geese with high or low egg production (4 for each group) were 3 years old, with good health, and under the same feeding condition. High-throughput sequencing technology was used to sequence cDNA libraries of the hypothalami, pituitary glands, and ovaries. The sequencing data were compared and analyzed, and the transcripts with significant differences were identified and analyzed with bioinformatics. The study showed that the transcriptome sequencing data of the 24 samples contained a total of 1,176,496,146 valid reads and 176.47 gigabase data. Differential expression analyses identified 135, 56, and 331 genes in the hypothalami, pituitary glands, and ovaries of Xinjiang Yili geese with high and low egg production. Further annotation of these differentially expressed genes in the non-redundant protein sequence database (Nr) revealed that 98, 52, and 309 genes were annotated, respectively. Through the annotations of GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) databases, 30 candidate genes related to the egg production of Xinjiang Yili geese were preliminarily selected. The gap junction, focal adhesion, and ECM-receptor interaction signaling pathways were enriched with the hypothalamic, pituitary, and ovarian differentially expressed genes, and the calcium signaling pathway was enriched with the pituitary and ovarian differentially expressed genes. Thus, these pathways in the hypothalamic-pituitary-gonadal axis may play an important role in regulating egg production of Xinjiang Yili geese. The results provided the transcriptomic information of the hypothalamic-pituitary-gonadal axis of Xinjiang Yili geese and laid the theoretical basis for revealing the molecular mechanisms regulating the egg-laying traits of Xinjiang Yili geese.

Globally, there is an increased interest of the Food Industry, the Politicians and the consumers to be informed about the environmental impacts connected to the production and the supply of food products.In the framework of the Paris Agreement for Climate Change and the 2030 Agenda of the United Nations for Sustainable development, the European Union (EU) has set demanding targets for the years 2030 and 2050 regarding the mitigation of environmental impacts from all its economic activities. Within this legislative context, which is expected to become stricter, the Primary Sector in Greece in general and the Livestock Production Sector more specifically are and will be obliged to contribute to the accomplishment of these goals (at country and EU level).Recent studies have highlighted the increased importance of livestock production systems regarding global environmental pollution and the discussion about implementation of strategies at the farm level for mitigation of environmental impacts has already started. Evaluating such actions on the supply chain level, allows to ensure that these actions do not cause negative environmental effects (problem shifting) to other stages of the supply chain apart from the livestock farm and eventually to the supply chain in total. To this respect, Life Cycle Assessment (LCA) is considered and has been suggested as a suitable methodology for environmental impact assessment.It has to be noticed that differences in the supply chain systems and production practices of livestock products as well as differences in the climatic conditions that these systems occur, lead with high certainty in differences regarding their environmental performance. Τhere is also a lack of environmental LCA (ELCA) research which refers to Greek agricultural and livestock goods or the Food Industry. Implementation of ELCA further requires specialized scientific knowledge and the use of software for which special training is required. Thus, the access of Greek livestock farmers (but also other stakeholders of the livestock products’ supply chains) to the information that ELCA provides is almost impossible in the current conditions. Taking into consideration the aforementioned information, the goal of this PhD Research was to present the first estimates regarding the environmental performance of important livestock production systems in Greece (i.e. raw milk supply chains from dairy cattle farming and sheep and goat farming, animal live-weight supply chain from pig farming and broiler farming), by focusing on collecting data from commercial livestock farms and implementing the LCA methodology (adjusting the LCA methodology to case studies). Throughout the Thesis, focus was given on the compilation of life cycle inventories and models for the studied systems. In the case that more than one supply chain systems are involved, this research attempted to identify the reasons for variations in the environmental performance. This PhD Research further attempted to assess the effect of targeted modifications in livestock production practices (and more specifically in the rations of broiler chickens and fattening pigs) which are interesting for Greece but also on a global level, on the environmental performance of the respective supply chain systems. Within this Thesis, a discussion on how Precision Livestock Farming (PLF) technologies could be used in combination with the ELCA methodology in an effort to improve the environmental performance of a livestock product, was further initiated. Finally, in the framework of this PhD Research two easy-to-use tools for environmental impact assessment by using the LCA methodology (calculators for Greek intensive broiler and sheep and goat production processes) were developed.This PhD Thesis consists of 5 separate sections. In Section 1, an introduction to the legislative framework regarding environmental protection in the EU was presented, the importance of studying the environmental impacts of livestock systems was discussed, principles and important definitions of the ELCA methodology were given and the goals of this PhD Research were set. The rest of the sections constitute the core of this PhD research.The aim of Section 2 was to use a ‘cradle-to-farm-gate’ ELCA in order to estimate the environmental performance of the supply chain of the cow-milk produced in a dairy cattle farm located in the Region of Thessaly, Greece. The functional unit was equal to 1kg of Fat and Protein Corrected Milk (FPCM). This section also aimed to discuss a possible link between the ELCA methodology and Precision Livestock Farming technologies. The results of the Life Cycle Inventory (LCI) revealed that the enteric fermentation of cattle, the excretion and storage of manure and slurry application in ryegrass production were the most important contributing processes at the farm level to the total methane, nitrous oxide and ammonia emissions in this partial life-cycle of cow-milk. The Life Cycle Impact Assessment (LCIA) results suggested the following environmental hot spots for the studied supply chain and for the various impact categories studied (i.e. climate change, fossil fuel depletion, human and ecological toxicity, acidification, eutrophication, water depletion and land use): a) enteric fermentation of cattle, b) on-farm slurry handling, c) soybean cultivation in foreign countries (Argentina, Brazil and USA), d) domestic electricity production and e) domestic production of maize grain and silage. It is finally argued that the ELCA method could be used complementarily with PLF technologies in an effort to improve the quality of environmental impact assessment results of the supply chains of livestock products.In the context of Section 3, an experimental study was conducted to examine the combined effects of adding a dietary protease, reducing the levels of soybean meal (SBM) and introducing corn gluten meal (CGM) in the ration of a group of broilers reared on a commercial Greek farm (Region of Central Macedonia). Five hundred forty chicks were divided into three dietary treatments with six replicates of thirty birds each. The first group (Control) was fed a conventional diet based on corn and soybean meal, containing 21% w/w crude protein (CP). The second group (Soy-Prot) was supplied a corn and SBM-based diet containing a lower level of CP (20% w/w) and 200 mg of the protease RONOZYME® Proact per kg of feed. The third group (Gluten-Prot) was fed a diet without soybean-related constituents which was based on corn and CGM and with CP and protease contents identical to those of the diet of the Soy-Prot group. Body weight, feed intake and feed conversion ratio (FCR) were evaluated. Furthermore, a partial ELCA was performed in order to assess the potential environmental performance of the systems defined by these three dietary treatments and identify their environmental hot-spots. The growth performance of the broilers supplied the Soy-Prot diet was similar to the broilers supplied the Control diet. However, the broilers which were fed the Gluten-Prot diet at the end of the trial showed a tendency (P≤0.010) for lower weight gain and feed intake compared to those of the Control diet. The ELCA suggested that the ammonia and nitrous oxide emissions due to litter handling constitute the farm level hot-spots for the Acidification and Eutrophication Potentials of the Control and Soy-Prot systems and the Global Warming Potential of the Gluten-Prot system, respectively. The Latin American soybean production and domestic corn production and lignite mining are important off-farm polluting processes for the studied life cycles. The Soy-Prot and Gluten-Prot systems both performed better than the Control system in nine of Environmental Impact Category Indicators assessed, with the respective differences being generally larger for the Gluten-Prot system. The environmental impact estimates are regarded as initial, indicative figures due to their inherent uncertainty. Overall, the results could be considered as positive indications in the effort to replace the conventional, soybean-dependent control diet in the specific broiler production system in an environmentally friendly way. In Section 3, an environmental footprint calculator appropriate for the intensive broiler live-weight supply chains in Greece was further developed, based on an attributional ‘cradle-to-farm-gate’ ELCA methodology. It consists of an MS excel workbook whose user is invited to provide a number of inputs concerning the animal capital grown, its nutrition, the bedding material used, transport distances and fuel and electricity consumption. As a result, ten environmental impact category indicators (EICI’s) are estimated, among which the Acidification Potential (AP), the Eutrophication Potential (EP), the Cumulative Energy Demand (CED) and the Global Warming Potential (GWP100).In Section 4, an in situ experimental procedure was performed in order to investigate the effect of supplementing the conventional diet (CNVD) supplied to the fattening pigs of a commercial pig farm in Greece (located in Epirus Region) (based on maize, barley, wheat bran and soybean meal) with 0.4% w/w attapulgite and 0.5% w/w benzoic acid at the expense of maize (ATTBAD diet) on their feed efficiency and growth performance. The results suggested a significant increase (p≤0.05) in the weight gain (TWG) and the slaughter live-weight and a significant decrease (p≤0.05) in the feed intake (FI) and feed conversion ratio per fattening pig when supplied the ATTBAD. These results were further used as an input to a ‘cradle-to-farm-gate’ environmental Life Cycle Assessment (ELCA). The functional unit (FU) was 1 kg of sold pig live-weight and the environmental impact categories (EICs) assessed were climate change (CC) and CC from direct land use change, acidification, eutrophication, land use, water use and fossil energy use. The indicators for all EICs (EICIs) were