Reproductive Rhythm Research Articles

Reproduction in deep-sea vent shrimps is influenced by diet, with rhythms apparently unlinked to surface production.

Variations in offspring production according to feeding strategies or food supply have been recognized in many animals from various ecosystems. Despite an unusual trophic structure based on non‐photosynthetic primary production, these relationships remain largely under‐studied in chemosynthetic ecosystems. Here, we use Rimicaris shrimps as a study case to explore relationships between reproduction, diets, and food supply in these environments. For that, we compared reproductive outputs of three congeneric shrimps differing by their diets. They inhabit vents located under oligotrophic waters of tropical gyres with opposed latitudes, allowing us to also examine the prevalence of phylogenetic vs environmental drivers in their reproductive rhythms. For this, we used both our original data and a compilation of published observations on the presence of ovigerous females covering various seasons over the past 35 years. We report distinct egg production trends between Rimicaris species relying solely on chemosymbiosis—R. exoculata and R. kairei—and one relying on mixotrophy, R. chacei. Besides, our data suggest a reproductive periodicity that does not correspond to seasonal variations in surface production, with substantial proportions of brooding females during the same months of the year, despite those months corresponding to either boreal winter or austral summer depending on the hemisphere. These observations contrast with the long‐standing paradigm in deep‐sea species for which periodic reproductive patterns have always been attributed to seasonal variations of photosynthetic production sinking from the surface. Our results suggest the presence of an intrinsic basis for biological rhythms in the deep sea, and bring to light the importance of having year‐round observations in order to understand the life history of vent animals.

Melatonin Receptors: A Key Mediator in Animal Reproduction.

Simple SummaryAnimal reproduction is closely related to economic benefits and food safety in domestic animals, as well as human fertility. There are many factors that affect the reproductive ability of animals, among which studies have confirmed that melatonin can affect animal reproduction. Melatonin receptors play important roles in mediating melatonin signaling, and they are expected to become a drug target for the improvement of animal reproduction capacity and treatment of reproductive diseases. In this review, we briefly summarize melatonin receptors MT1- and MT2-mediated signal transduction, as well as their role in reproductive regulation, including their effects on gametogenesis, gamete quality, reproductive rhythm, endocrine function, and embryonic development. We also briefly summarize the developments in pharmacological research regarding melatonin receptors as drug targets, which can provide a future perspective for the development of drugs and therapeutic methods based on melatonin receptors or their mediated signaling pathways.Melatonin, a hormone produced by the mammalian pineal gland, influences various physiological activities, many of which are related to animal reproduction, including neuroendocrine function, rhythm regulation, seasonal behavior, gonadogenesis, gamete development and maturation, sexual maturation, and thermoregulation. Melatonin exerts beneficial actions mainly via binding with G-protein-coupled receptors (GPCR), termed MT1 and MT2. Melatonin receptors are crucial for mediating animal reproduction. This paper reviews the characteristics of melatonin receptors including MT1 and MT2, as well as their roles in mediating signal transduction and biological effects, with a focus on their function in animal reproduction. In addition, we briefly summarize the developments in pharmacological research regarding melatonin receptors as drug targets. It is expected that this review will provide a reference for further exploration and unveiling of melatonin receptor function in reproductive regulation.

Influence of precipitation on reproductive phenophases in Moringa oleifera Lam

Phenology works as an indicator of the response of plants to local climatic and edaphic conditions, enabling a better understanding of the dynamics of the species. The seasonal climate also influences the occurrence of periodic rhythms of growth and reproduction (phenophases). Moringa oleifera Lam., belong to the Moringaceae family, is widely distributed in tropical countries and easily adapts to semiarid conditions, having medicinal value as a forage, flavoring, in the cosmetics, honey, fuel and in the treatment of water purification through the coagulant solution made from the seeds. The objectives of the present work were to study the phenological behavior of M. oleifera and to relate the variations in phenophases with climatic factors, precipitation and temperature. For collection of phenological data, ten trees were selected, and the records were carried out between the first half of August 2020 and the first half of July 2021. The observations were carried out at fortnightly intervals, recording the presence and absence of the flowering and fruiting phenophases including flowering – period in which the tree is in full flowering; fructification – which starts from the moment that small fruits are visible after the fertilization of the flowers and ends with the dispersal of seeds. The Fournier intensity index was determined using a semiquantitative interval scale of five categories (0 to 4), with an interval of 25% between each category. The phenological data of intensity of each phenophase (flowering and fruiting) were related to precipitation and average temperature fortnightly using Spearman's correlation. The flowering and fruiting phenophases of M. oleifera intensified in August, September and December 2020, showing Fournier intensity peaks of 47.5 and 77.5, 72.5 and 92.5, and 35 and 55 %, respectively, and April and June 2021, in the monthly intervals of greater rainfall, with percentage rates of 82.5 and 95, 77.5 and 80%, respectively. In general, we found that M. oleifera produced seeds between the first half of August and the first half of September, and the second half of December 2020, and the second half of April and the first half of June 2021. Thus, it can be stated that the production of fruits by M. oleifera is interrupted in the months with less rainfall (October to November 2020, and January to February 2021). The intensity and duration of the flowering and fruiting phenophases in M. oleifera are synchronized with the temporal distribution of the precipitation pulses in that habitat

Auditory perception dominates in motor rhythm reproduction.

It is commonly agreed that vision is more sensitive to spatial information, while audition is more sensitive to temporal information. When both visual and auditory information are available simultaneously, the modality appropriateness hypothesis predicts that, depending on the task, the most appropriate (i.e., reliable) modality dominates perception. While previous research mainly focused on discrepant information from different sensory inputs to scrutinize the modality appropriateness hypothesis, the current study aimed at investigating the modality appropriateness hypothesis when multimodal information was provided in a nondiscrepant and simultaneous manner. To this end, participants performed a temporal rhythm reproduction task for which the auditory modality is known to be the most appropriate. The experiment comprised an auditory (i.e., beeps), a visual (i.e., flashing dots), and an audiovisual condition (i.e., beeps and dots simultaneously). Moreover, constant as well as variable interstimulus intervals were implemented. Results revealed higher accuracy and lower variability in the auditory condition for both interstimulus interval types when compared to the visual condition. More importantly, there were no differences between the auditory and the audiovisual condition across both interstimulus interval types. This indicates that the auditory modality dominated multimodal perception in the task, whereas the visual modality was disregarded and hence did not add to reproduction performance.

Musical Performance in Adolescents with ADHD, ADD and Dyslexia-Behavioral and Neurophysiological Aspects.

Research has shown that dyslexia and attention deficit (hyperactivity) disorder (AD(H)D) are characterized by specific neuroanatomical and neurofunctional differences in the auditory cortex. These neurofunctional characteristics in children with ADHD, ADD and dyslexia are linked to distinct differences in music perception. Group-specific differences in the musical performance of patients with ADHD, ADD and dyslexia have not been investigated in detail so far. We investigated the musical performance and neurophysiological correlates of 21 adolescents with dyslexia, 19 with ADHD, 28 with ADD and 28 age-matched, unaffected controls using a music performance assessment scale and magnetoencephalography (MEG). Musical experts independently assessed pitch and rhythmic accuracy, intonation, improvisation skills and musical expression. Compared to dyslexic adolescents, controls as well as adolescents with ADHD and ADD performed better in rhythmic reproduction, rhythmic improvisation and musical expression. Controls were significantly better in rhythmic reproduction than adolescents with ADD and scored higher in rhythmic and pitch improvisation than adolescents with ADHD. Adolescents with ADD and controls scored better in pitch reproduction than dyslexic adolescents. In pitch improvisation, the ADD group performed better than the ADHD group, and controls scored better than dyslexic adolescents. Discriminant analysis revealed that rhythmic improvisation and musical expression discriminate the dyslexic group from controls and adolescents with ADHD and ADD. A second discriminant analysis based on MEG variables showed that absolute P1 latency asynchrony |R-L| distinguishes the control group from the disorder groups best, while P1 and N1 latencies averaged across hemispheres separate the control, ADD and ADHD groups from the dyslexic group. Furthermore, rhythmic improvisation was negatively correlated with auditory-evoked P1 and N1 latencies, pointing in the following direction: the earlier the P1 and N1 latencies (mean), the better the rhythmic improvisation. These findings provide novel insight into the differences between music processing and performance in adolescents with and without neurodevelopmental disorders. A better understanding of these differences may help to develop tailored preventions or therapeutic interventions.

Rhythmic ability decline in aging individuals: The role of movement task complexity

Abstract Study aim: To investigate age-related changes in rhythmic reproduction ability in relation to the complexity of the adopted movement task. Material and methods: A Stereophotogrammetric system was used to quantify individual rhythmic performances through motion analysis. Seventeen younger adult (age: 34.8 ± 4.2 yrs) and sixteen older adult (age: 69.9 ± 3.8 yrs) sedentary individuals volunteered for this study. Participants were administered a rhythmic test, which included three different rhythmic patterns to be reproduced by means of finger-tapping, foot-tapping and walking. Number of correct reproductions, time delays and rhythmic ratios were assessed and submitted to analysis of variance. Results: For all rhythmic parameters, age-related differences emerged about rhythmic patterns and motor tasks. Older adults showed reduced accuracy as compared to their younger counterparts with a marked tendency to speed up beats reproduction (p < 0.05). Increased movement complexity negatively influenced rhythmic ability, with worst performances in the walking task (p < 0.05). Conclusions: Complexity of the motor reproduction worsen rhythmic ability. Future research should focus on how specific rhythmic training with progressive movement task complexity could contrast this age-related decline.

The Impact of Re-Mating Interval and Genotype on Physiological Response of Rabbits after First Kindling

This is an experiment aimed to study the effect of re-mating interval on rabbit does after first kindling on hormonal (insulin, leptin, and T3) and metabolites (triglycerides, urea, and glucose) levels. DNA damage in ovary cells of rabbit does during the 2nd parity was also studied. Two varieties were used: APRI (synthetic line) and Baladi Black (BB, Egyptian breed). A total number of 120 mature rabbit does (60 does for each breed) were 6 months of age and were used at the beginning of the breeding season. Does of each breed were divided into three equal groups according to reproductive rhythm. The 1st group was postpartum (PP). The 2nd group was 11 days after parturition (P11). The 3rd group was post-weaning (PW). There were significant (P≥0.05) differences in plasma leptin concentration during 1st parity. The highest value of plasma leptin concentration was recorded by the PW group at mating. Also, there were significant differences in plasma insulin and T3 hormones concentrations of doe rabbits. The highest value of plasma insulin concentration was recorded by the PW group at mating in 1st parity and the highest value of plasma T3 hormone concentration was recorded for the PS group at mating. While there were insignificant differences during 2nd parity in T3 hormone concentration in rabbits, the differences of plasma glucose and triglyceride concentrations of doe rabbits during 1st parity and 2nd parity were significant. However, the highest significant value of plasma glucose concentration was recorded by the PW group at mating. On the other hand, there were insignificant differences in plasma urea concentration of doe rabbits during 1st parity and 2nd parity. Finally, no significant effects were observed on comet length, head diameter, tail length, or DNA % tail.

Expressions of melanopsins in telencephalon imply their function in synchronizing semilunar spawning rhythm in the mudskipper Boleophthalmus pectinirostris

The mudskipper Boleophthalmus pectinirostris inhabits intertidal mudflats, exhibiting semilunar reproductive rhythms. To investigate whether melanopsin is possibly involved in the synchronization of the semilunar spawning rhythm in the female mudskipper, we first cloned all four melanopsin subtypes (opn4m1, opn4m3, opn4x1, opn4x2) in B. pectinirostris. Results from RTq-PCR showed that significantly higher transcription levels of all four melanopsin subtypes were observed in the eyes rather than other tissues. In brain, all four melanopsin subtypes were also detectable in different regions, including the telencephalon, in which the expression of melanopsin has not been reported in other teleosts. The transcription levels of opn4m3 and opn4x1 in the telencephalon exhibited a daily fluctuation pattern. When females entered the spawning season, opn4m1 and opn4x1 transcript levels increased significantly in the telencephalon. During the spawning season, the transcript levels of opn4m3 and opn4x1 in the telencephalon appeared to have a cyclic pattern associated with semilunar periodicity, exhibiting two cycles with a peak around the first or the last lunar quarters. Results from ISH showed that, opn4x1 mRNA was localized in the medial of dorsal telencephalic area, dorsal nucleus of ventral telencephalic area (Vd), ventral nucleus of ventral telencephalic area (Vv), anterior part of parvocellular preoptic nucleus, magnocellular part of the magnocellular preoptic nucleus (PMmc), habenular and ventral zone of hypothalamus. Intriguingly, gnrh3 mRNA was also located in Vd, Vv and PMmc. Taken together, our results suggested that melanopsins, e.g. opn4x1, expressed in the telencephalon might mediate semilunar spawning activity in the female mudskipper.

Effects of feed restriction during pregnancy on maternal reproductive outcome, foetal hepatic IGF gene expression and offspring performance in the rabbit

Primiparous female rabbits have high nutritional requirements and, while it is recommended that they are subjected to an extensive reproductive rhythm, this could lead to overweight, affecting reproductive outcomes. We hypothesised that restricting food intake during the less energetic period of gestation could improve reproductive outcome without impairing offspring viability. This study compares two groups of primiparous rabbit does in an extensive reproductive programme, one in which feed was restricted from Day 0 to Day 21 of gestation (R021), and another in which does were fed ad libitum (control) throughout pregnancy. The mother and offspring variables compared were (1) mother reproductive outcomes at the time points pre-implantation (Day 3 postartificial insemination [AI]), preterm (Day 28 post-AI) and birth; and (2) the prenatal offspring characteristic IGF system gene expression in foetal liver, liver fibrosis and foetus sex ratio, and postnatal factor viability and growth at birth, and survival and growth until weaning. Feed restriction did not affect the conception rate, embryo survival, or the number of morulae and blastocysts recovered at Day 3 post-AI. Preterm placenta size and efficiency were similar in the two groups. However, both implantation rate (P < 0.001) and the number of foetuses (P = 0.05) were higher in the R021 mothers than controls, while there was no difference in foetal viability. Foetal size and weight, the weights of most organs, organ weight/BW ratios and sex ratio were unaffected by feed restriction; these variables were only affected by uterine position (P < 0.05). Conversely, in the R021 does, foetal liver IGBP1 and IGF2 gene expression were dysregulated despite no liver fibrosis and a normal liver structure. No effects of restricted feed intake were produced on maternal fertility, prolificacy, or offspring birth weight, but control females weaned more kits. Litter weight and mortality rate during the lactation period were also unaffected. In conclusion, pre-implantation events and foetal development were unaffected by feed restriction. While some genes of the foetal hepatic IGF system were dysregulated during pregnancy, liver morphology appeared normal, and the growth of foetuses and kits until weaning was unmodified. This strategy of feed restriction in extensive reproductive rhythms seems to have no significant adverse effects on dam reproductive outcome or offspring growth and viability until weaning.

Photoperiodic modulation of ovarian metabolic, survival, proliferation and gap junction markers in adult golden hamster, Mesocricetus auratus

Female reproductive physiology is greatly dependent on tight regulation of metabolic and survival factors. Photoperiod regulates female reproductive rhythms but very less information exists explaining whether photoperiod could modulate thyroid hormone homeostasis, metabolic/energy parameters along with survival, proliferation and gap junction proteins in the ovary of a long-day breeder, Mesocricetus auratus. Adult female hamsters were exposed to different photoperiodic regimes i.e., critical photoperiod (CP; 12.5L:11.5D), short photoperiod (SP; 8L:16D) and long photoperiod (LP; 16L:8D) for 12 weeks. LP upregulated thyroidal and gonadal activity as apparent by histoarchitecture, thyroid hormone profile [triiodothyronine (T3), thyroxin (T4) and thyroid stimulating hormone (TSH)], luteinizing hormone (LH), follicle stimulating hormone (FSH), estradiol (E2) and progesterone (P4) levels when compared with SP exposed hamsters. Further, LP increased thyroid hormone receptor-α/deiodinase-2 (TRα/Dio-2), estrogen receptor-α (ERα)/aromatase and insulin receptor/glucose transporter-4 (IR/GLUT-4) expressions in ovary. Interestingly, ovarian sirtuin-1 (SIRT-1) expression was also upregulated under LP condition along with cell proliferation (proliferating cell nuclear antigen or PCNA), survival (B cell lymphoma-2 or Bcl-2) and gap junction (connexin-43) markers when compared to SP exposed hamsters. We also noted elevated levels of circulatory leptin, insulin along with melatonin and its receptor (MT-1) in ovary under SP condition. Thus, we suggest that photoperiod plays a vital role in regulation of thyroid and reproductive hormone homeostasis along with key metabolic and survival markers in the ovary of adult golden hamsters, M. auratus providing further insight into the regulation of female reproductive seasonality in a long-day breeder.

Revelation of candidate genes and molecular mechanism of reproductive seasonality in female rohu (Labeo rohita Ham.) by RNA sequencing

BackgroundCarp fish, rohu (Labeo rohita Ham.) is important freshwater aquaculture species of South-East Asia having seasonal reproductive rhythm. There is no holistic study at transcriptome level revealing key candidate genes involved in such circannual rhythm regulated by biological clock genes (BCGs). Seasonality manifestation has two contrasting phases of reproduction, i.e., post-spawning resting and initiation of gonadal activity appropriate for revealing the associated candidate genes. It can be deciphered by RNA sequencing of tissues involved in BPGL (Brain-Pituitary-Gonad-Liver) axis controlling seasonality. How far such BCGs of this fish are evolutionarily conserved across different phyla is unknown. Such study can be of further use to enhance fish productivity as seasonality restricts seed production beyond monsoon season.ResultA total of ~ 150 Gb of transcriptomic data of four tissues viz., BPGL were generated using Illumina TruSeq. De-novo assembled BPGL tissues revealed 75,554 differentially expressed transcripts, 115,534 SSRs, 65,584 SNPs, 514 pathways, 5379 transcription factors, 187 mature miRNA which regulates candidate genes represented by 1576 differentially expressed transcripts are available in the form of web-genomic resources. Findings were validated by qPCR. This is the first report in carp fish having 32 BCGs, found widely conserved in fish, amphibian, reptile, birds, prototheria, marsupials and placental mammals. This is due to universal mechanism of rhythmicity in response to environment and earth rotation having adaptive and reproductive significance.ConclusionThis study elucidates evolutionary conserved mechanism of photo-periodism sensing, neuroendocrine secretion, metabolism and yolk synthesis in liver, gonadal maturation, muscular growth with sensory and auditory perception in this fish. Study reveals fish as a good model for research on biological clock besides its relevance in reproductive efficiency enhancement.

Seminal Vesicles and Bulbourethral Glands of Mammals: Morphology, Physiology, Ecology, Action of Extreme Destabilizing Factors

In mammals, the adnexal sex glands are represented by seminal vesicles, the prostate gland, urethral and bulbourethral glands, as well as glands that coagulate sperm and ampullary glands. The secret of the accessory genital glands increases the volume of the ejaculate (the share of secretions of these glands accounts for about 95% of the volume of ejaculate) promotes sperm, causes increased contraction of smooth muscle cells in the walls of the female genital tract.The purpose of this review is to analyze the morphofunctional organization of seminal vesicles and bulbourethral glands of mammalian animals and humans.The presence or absence of seminal vesicles is a species-specific feature. Among mammals, seminal vesicles are well developed in some rodents, insectivores, a number of domestic animals (cattle, pigs), and primates. These glands are absent in cloacae, marsupials, some carnivores, a number of insectivores, artiodactyls. Bulbourethral glands are well developed in rodents, bats, primates, and some ungulates.In the wall of the seminal vesicles, the mucous, muscular and outer membranes are isolated. The epithelium of the secretory parts is pseudomultitial, the interstitium is represented by loose fibrous connective tissue and a significant number of smooth muscle cells. In the wall of the bulbourethral glands, the mucosa and adventitial membrane are isolated. The secretory end sections of the bulbourethral glands are lined with a single-layer single-row epithelium, glandular cells produce a mucosal or mixed secret. The seminal vesicles and bulbourethral glands are androgen-dependent glands. In species with a seasonal pattern of reproduction, their morphofunctional characteristics undergo significant changes during the circannual rhythm of reproduction.The epithelium of seminal vesicles and bulbourethral glands is very sensitive to the action of various adverse factors (heavy metal compounds, organic xenobiotics, electromagnetic radiation, ultrasound, etc.). When exposed to various negative factors in the adnexal glands, a complex of changes occurs (edema of connective tissue and epithelium, decreased secretory activity of epithelial cells, desynchronization of the secretory cycle, desquamation of glandular epithelial cells, proliferation of interstitial connective tissue).There is a lack of information on many aspects of the characteristics of the adnexal glands of the male reproductive system, primarily on the morphology and physiology of the adnexal glands of animals in natural ecosystems, on the ultrastructural and immunohistochemical characteristics of these glands, as well as on the mechanisms of regulation of morphofunctional rearrangements of the adnexal glands during seasonal reproduction rhythms, in the conditions of adaptation to various negative influences.

Reproductive Performance of Hycole Rabbit Does, Growth of Kits and Milk Chemical Composition during Nine Consecutive Lactations under Extensive Rhythm.

Simple SummaryThe reproductive potential and longevity of rabbit does are the real determinants of the economic profitability of rabbit production. Another important characteristic is the quality of rabbit’s milk, as it determines the survival and growth of rabbit kits. The goal of this study was to examine the effect of parity order on the milk quality and the reproductive performance of Hycole does housed under intensive conditions of a commercial rabbit farm. The results of this trial and its duration allowed to trace the reproductive performance of Hycole females throughout their lifespan and to indicate the age boundary of a profitable reproductive performance of Hycole does.The goal of this study was to analyze the reproductive performance of does, growth of their kits, and chemical composition of their milk over nine consecutive parities in order to indicate the boundary of female reproductive profitability. The novelty of this study results from the combinations of three factors: extensive reproductive rhythm, commercial farming conditions, and a period of nine consecutive parities, showing the actual lifespan of a rabbit doe on commercial farms. The data was collected on 60 Hycole females kept at a commercial rabbit farm. Throughout the study, 32 does were excluded due to different reasons (e.g., excluded by means of selection—43.8% and mortalities—25.0%). The does were first inseminated at 28 weeks of age. Following artificial inseminations were conducted 14–15 days after each parturition. All kits were weaned at the age of 35 days. The following characteristics were analysed: body weight of rabbit does at artificial insemination, milk production per lactation, litter size, litter weight, average kit weight, and milk chemical composition. Rabbit does had a significant decrease in kindling rate between the eighth and the ninth parity (by 10.0 percentage points; p = 0.039). The litter size at weaning in the ninth parity was significantly lower to litters weaned at other analysed parities. The amount of milk produced per lactation was affected by the parity order (6.31–6.76 kg; p = 0.042). The litter weights on day 21 and 35 were the lowest at ninth parity. The content of total solids (TS), solids-not-fat, and fat was affected by the parity order on both analysed lactation days. The content of TS and fat in rabbit milk was characterized with a decreasing trend over the analysed period, on both lactation days. The results clearly indicate that rabbit does under extensive reproductive cycles characterize with a very good reproductive performance and can be successfully used for reproduction even up to the eighth parity. However, further research is needed if keeping them longer will not be profitable.

Lunar Periodicity in Reproduction of Senatorial Scallop (Chlamys Senatoria Gmelin, 1791) in Asid Gulf, Masbate, Philippines

Abstract In Masbate, senatorial scallop Chlamys senatoria is one of the five commercially important species of scallop present in Asid Gulf, but its basic biology is poorly understood in the Philippines. To provide biological information for future conservation and management, the reproductive rhythm of senatorial scallop in relation to lunar phase was investigated from October 2016 to March 2017. Scallops were collected daily from the fishers’ catches and were measured, dissected, and processed for histological analysis; whereas, fecundity and size of eggs (diameter) were also determined. Ecological parameter such as bottom water temperature was monitored during the sampling period. Results showed that C. senatoria is a highly fecund species, which ranges from 8.3 X 105 to 2.1 X 106 oocytes per female and its sizes (oocytes) ranges from 53.8 µm to 72.5 µm while Gonado-somatic index (GSI) ranges from 3.2 to 7.1. Fecundity, egg diameter, and the GSI decreased during new moon (NM) and full moon (FM). GSI indicates that the onset of spawning activity commences during NM and FM. Environmental parameters that were monitored showed significant variations in relation to lunar phase. Spawning of scallop C. senatoria follows a lunar reproductive pattern, which was initiated and influenced by the variations of different factors such as temperature, water amplitude, and light as the effect of lunar/tidal cycles. These findings indicate that reproduction and necessarily spawning in the scallop are related to factors associated with lunar phases. Strategies for managing the resource can be formulated using the temporal dimension of lunar phases.

Geographic distributions shape the functional traits in a large mammalian family.

Traits of organisms are shaped by their living environments and also determined in part by their phylogenetic relationships. For example, phylogenetic relationships often affect the geographic distributions of animals and cause variation in their living environments, which usually play key roles in the life history and determine the functional traits of species. As an ancient family of mammals, bears widely distribute and have evolved some specific strategies for survival and reproduction during their long‐term evolutionary histories. Many studies on the ecology of bears have been conducted in recent decades, but few have focused on the relationships between their geographic distributions and ecological adaptations. Here, using bears as a model system, we collected and reanalyzed data from the available literatures to explore how geographic distributions and phylogenetic relationships shape the functional traits of animals. We found a positive relationship between phylogenetic relatedness and geographic distributions, with bears distributed in adjacent areas applying more similar strategies to survive and reproduce: (a) Bears living at high latitudes consumed a higher proportion of vertebrates, which may provide more fat for adaptation to low temperatures, and (b) their reproduction rhythms follow fluctuations in seasonal forage availability and quality, in which bears reach mating status from March to May and give birth in approximately November or later.

Characteristics of meat, pet, and research rabbit farms in Brazil: An overview based on twelve farms

&lt;p&gt;Rabbit production has great growth potential in a country where animal production is very important. However, there is little data about this industry in Southern and Southeast Brazil. The aim of this study was to describe Brazilian rabbit farms that provide meat, pets and animals for learning or research. Three pet farms, four meat farms and five research rabbit farms were visited, and the production and farm characteristics data were collected between June 2018 and March 2019. A total of 1170 rabbits and 617 cages were evaluated. Most farms had 21 to 60 (58.3%) does. Considering all farms, the farmers reported an average rate of conception of 71.8%, prolificacy rate of 6.7 kits per parturition, average interval between parturitions of 65 d and 6.3 parturitions/doe yr. The mean mortality rate for breeding rabbits was 10.4%, compared to 1.7% for growing rabbits (rabbits post-weaning until slaughter or sale). The average area of a cage was 0.43±0.1 m², with an average stocking density for growing rabbits of 3 rabbits/m². The most common cage system used by farmers was a flat-deck (66.7% of farms) system with a wire cage (91.7%). Metal (41.7%) and clay (33.3%) feeders were the most common types of feeders, and automatic nipple drinkers were present in 75% of the farms. Dirt accumulation was observed in 11.2% of the cages and 5.7% of the drinkers, but not in feeders. A total of 4.1% of the cages were considered unsafe, and 0.8% had problems with the drinkers. The farms studied ranged from small to medium in size, used an extensive reproductive rhythm and followed basic production techniques. Animal health and management aspects need to be reviewed by the farmer if the rabbit production conditions are to improve.&lt;/p&gt;

Effects of an Interventional Music Program on Learning Skills of Primary-School Students with Dyslexia

Research has shown that children with dyslexia have difficulties perceiving rhythm, and that musical training can enhance their learning skills. The purpose of this research was to investigate the effectiveness of an interventional music-training program based on rhythm-perception enhancement, within the curriculum of the music course in Greece. For this purpose, this research was conducted on primary school students over a period of 12 weeks. Thirty-two students of the 4th Elementary class, diagnosed with dyslexia, participated in the study. The LAMDA (Learning Skills and Weakness Detection Software) test, a weighted tool for automated detection of learning difficulties in written and oral language, was used to assess the improvement of children. The assessment showed that the interventional music-training program improved students' performance in areas such as word recognition, grammar spelling, visual sequences and rhythm reproduction. The research findings indicate that the incorporation of an appropriately adapted music program into the primary school curriculum, as well as the use of music as a systematic treatment, may have positive effects on students with dyslexia.

Global feed conversion in semi-intensive rabbit production system of Argentina.

The global feed conversion is a variable used to measure feed efficiency in production systems. The number of rabbits produced/doe/year is the most influential factor on production cost. Feeding can be considered a variable cost in livestock, because it varies with the number of rabbits, and that cost becomes diluted when the number of rabbits produced increases. The aim of the present work was to analyze factors that influenced the global feed conversion ratio (FCR) of a semi-intensive rabbit production system of Azul, Buenos Aires province, Argentina. Five breeds (Californian, New Zealand White, New Zealand Black, Butterfly, and Fauve de Bourgogne) were used. The doe productivity varied according to the applied reproduction rhythm (p=0.002), being an average of 1.29±0.09 animal produced/doe/month for the rhythm of 52 days, and 2.38±0.28 for the rhythm of 42 days. The fertility rate was on the average 65% and 77% for the reproductive rhythm of 52 to 42 days respectively. A total of 20,091 kg of feed was required to produce 1027 rabbits (19.6 kg/animal), with a global feed conversion rate of 6.9. The slaughter weight varied according to the applied reproduction rhythm (p=0.008), with an average of 2.79±0.10 kg. However, in the first period, rabbits were heavier (3.31±0.15 kg). The rabbit/feed price ratio was 12.8 to 16 depending on the sale price (retail or wholesale), respectively. The doe productivity was different according the reproductive rhythm applied, and this affected the FCR and the feed consumed/rabbit produced.

Impacts of using a social robot to teach music to children with low-functioning autism

Abstract This article endeavors to present the impact of conducting robot-assisted music-based intervention sessions for children with low-functioning (LF) autism. To this end, a drum/xylophone playing robot is used to teach basic concepts of how to play the instruments to four participants with LF autism during nine educational sessions. The main findings of this study are compared to similar studies conducted with children with high-functioning autism. Our main findings indicated that the stereotyped behaviors of all the subjects decreased during the course of the program with an approximate large Cohen’s d effect size. Moreover, the children showed some improvement in imitation, joint attention, and social skills from the Pre-Test to Post-Test. In addition, regarding music education, we indicated that while the children could not pass a test on the music notes or reading music phrases items because of their cognitive deficits, they showed acceptable improvements (with a large Cohen’s d effect size) in the Stambak Rhythm Reproduction Test, which means that some rhythm learning occurred for the LF participants. In addition, we indicated that parenting stress levels decreased during the program. This study presents some potential possibilities of performing robot-assisted interventions for children with LF autism.

Reproduction Accuracy for Short Rhythms Following Melodic or Monotonic Presentation

Some researchers and study participants have expressed an intuition that novel rhythmic sequences are easier to recall and reproduce if they have a melody, implying that melodicity (the presence of musical pitch variation) fundamentally enhances perception and/or representation of rhythm. But the psychoacoustics literature suggests that pitch variation often impairs perception of temporal information. To examine the effect of melodicity on rhythm reproduction accuracy, we presented simple nine-note auditory rhythms to 100 college students, who attempted to reproduce those rhythms by tapping. Reproductions tended to be more accurate when the presented notes all had the same pitch than when the presented notes had a melody. Nonetheless, a plurality of participants judged that the melodically presented rhythms were easier to remember. We also found that sequences containing a Scotch snap (a sixteenth note at a quarter note beat position followed by a dotted eighth note) were reproduced less accurately than other sequences in general, and less accurately than other sequences containing a dotted eighth note.