Brood Stages Research Articles

Molecular and transcriptomic analysis of the ovary during laying and brooding stages in Zhedong white geese (Anser cygnoides domesticus)

ABSTRACT 1. This study investigates the molecular mechanisms affecting brooding in Zhedong white geese by examining differences in reproductive endocrine levels, ovarian histology and transcriptomics. 2. Twenty 18-month-old Zhedong white geese were selected to examine their ovaries using histological, biochemical, molecular biological, and high-throughput sequencing techniques during the laying and brooding periods. 3. The results showed that the number of atretic follicles and apoptotic cells in the ovaries increased significantly (p < 0.05), the levels of follicle-stimulating hormone, luteinising hormone, gonadotropin-releasing hormone and oestradiol decreased significantly (p < 0.05), and the level of prolactin increased significantly (p < 0.01) during the brooding stage. 4. In broody geese, the expression of CASP3, CASP9, P53, BAX, and Cyt-c were considerably higher (p < 0.05), but BCL2 expression was significantly lower (p < 0.05). 5. In ovarian tissues, 260 differentially expressed lncRNAs, 13 differentially expressed miRNA and 60 differentially expressed mRNA were all discovered using transcriptome sequencing analysis. Functional enrichment analysis revealed that the differentially expressed mRNA and non-coding RNA target genes were primarily involved in ECM-receptor interaction, cell adhesion, cardiac muscle contraction, mTOR signalling, and the calcium signalling pathway. 6. In conclusion, follicular atrophy and apoptosis occurred in the ovaries and serum reproductive hormone levels were significantly changed during the brooding period of Zhedong white geese. COL3A1, COL1A2, GRIA1, RNF152, miR-192, and miR-194 may be important candidates for the regulation of brooding behaviour, with the mTOR signalling pathway playing a key role.

Automated precision beekeeping for accessing bee brood development and behaviour using deep CNN.

Bees play a significant role in the health of terrestrial ecosystems. The decline of bee populations due to colony collapse disorder around the world constitutes a severe ecological danger. Maintaining high yield of honey and understanding of bee behaviour necessitate constant attention to the hives. Research initiatives have been taken to establish monitoring programs to study the behaviour of bees in accessing their habitat. Monitoring the sanitation and development of bee brood allows for preventative measures to be taken against mite infections and an overall improvement in the brood's health. This study proposed a precision beekeeping method that aims to reduce bee colony mortality and improve conventional apiculture through the use of technological tools to gather, analyse, and understand bee colony characteristics. This research presents the application of advanced digital image processing with computer vision techniques for the visual identification and analysis of bee brood at various developing stages. The beehive images are first preprocessed to enhance the important features of object. Further, object is segmented and classified using computer vision techniques. The research is carried out with the images containing variety of immature brood stages. The suggested method and existing methods are tested and compared to evaluate efficiency of proposed methodology.

Efficacy and trade-offs of an innovative hyperthermia device to control Varroa destructor in honeybee colonies

For decades, the honeybee, Apis mellifera, has suffered from severe colony losses due to the ectoparasitic mite Varroa destructor. Various strategies based on chemicals fail to adequately control varroa mite populations, and often comprise side-effects on the host, parasite resistance and residues in hive products. Reduced temperature tolerance of V. destructor compared to its host has long been recognised and accordingly, the potential of hyperthermia to disrupt mite reproduction within honeybee brood cells or even kill adult parasites. Yet, earlier studies on hyperthermia remain largely anecdotal, and readily implementable solutions have so far been lacking. This study investigates autonomously controlled interval heating from within brood combs throughout the season compared to control colonies maintained according to good apicultural practice. We documented treatment-dependent colony growth dynamics and honey production at three apiaries, complemented by regular monitoring of varroa mite levels and comprehensive digital assessments of brood development over time. Our one-year field trial suggests the evaluated hyperthermia device efficiently suppresses mite populations below critical thresholds until autumn. Whilst a general winter reference-curing revealed similar mite infestations of colonies previously treated with hyperthermia versus formic acid (control), only the latter imposed substantial overwintering burdens indirectly through frequent late-season queen supersedure. However, relative to targeted pupae, increased mortality particularly of heat-treated non-target brood stages (eggs and larvae) appeared to trigger compensatory colony-level responses, translating into temporarily decreased numbers of adult workers coupled with increased pollen foraging and overall lower honey harvests. Valuable insights into previously unrecognised side-effects of hyperthermia and mitigation thereof may ultimately permit successful routine applications of this chemical-free approach to combat the major threat to honeybees worldwide.

EFFECT OF DIETARY SUPPLEMENTATION OF ANIMAL BLOOD PLASMA POWDER ON PRODUCTION PERFORMANCE, DRESSED WEIGHT AND IMMUNE RESPONSE OF BROILER

Enhancing economical poultry production using low-cost animal blood plasma powder incorporated in poultry rations is a good step toward sustainable poultry production. The purpose of the present study was to evaluate the effect of dietary supplementation of animal blood plasma powder on production performance, dressed weight, and immune response of broilers. Bovine plasma was separated from the whole blood through centrifugation. A total of 240 day-old broiler chicks having uniform body weights were randomly assigned into 4 treatment groups (AP0, AP1, AP2, and AP3). Each group had three replicates of 20 chicks (n=3; 20 birds/replicate). Ross broiler management guidelines were followed for feeding, watering, and vaccination. broiler starter ration (23.2% CP and 2990kcalME/kg) was provided during the brooding stage and switched to the grower diet (20.08% CP and 3112 kcal/kg ME) up to 28 days and finisher (18.86% CP and 3208 kcal/kg ME). Animal blood plasma powder supplemented into the diet at different levels AP1 (0.5g/kg), AP2 (1g g/kg), AP3 (1.5g g/kg), and AP0 (Control 0g/kg) for different groups. The treatment was continued for seven weeks. Significantly lower (P&lt;0.05) feed intake (2809.3g±5.36) and high body weight gain (1513.3g±9.83) were found for the higher supplemented group compared to the non-supplemented group (1441.0g ±4.04). Overall FCR was significantly (p&lt; 0.05) lower for supplemented groups compared with the control group. The decreasing (p&lt; 0.05) trend in FCR in supplemented groups was increasing the level of bovine animal blood plasma supplementation in the diet. The dressing percentage was significantly (P&lt;0.05) higher for supplemented groups as compared to the control. Non-significant differences were observed in haemagglutination inhibition (HI) antibody titer against Newcastle disease and mortality among groups. It was concluded that animal blood plasma could be safely used in broiler ration for better performance without any loss to antibodies titer and mortality. Animal blood plasma has more capability to be used as an alternative and cheap source of protein in poultry ration.

WGCNA based identification of hub genes associated with cold response and development in Apis mellifera metamorphic pupae.

Honeybee is a crucial pollinator in nature, and plays an indispensable role in both agricultural production and scientific research. In recent decades, honeybee was challenged with health problems by biotic and abiotic stresses. As a key ecological factor, temperature has been proved to have an impact on the survival and production efficiency of honeybees. Previous studies have demonstrated that low temperature stress can affect honeybee pupation and shorten adult longevity. However, the molecular mechanism underlying the effects of low temperatures on honeybee growth and development during their developmental period remain poorly understood. In this paper, the weighted gene co-expression analysis (WGCNA) was employed to explore the molecular mechanisms underpinnings of honeybees' respond to low temperatures (20°C) during four distinct developmental stages: large-larvae, prepupae, early-pupae and mid-pupae. Through an extensive transcriptome analysis, thirteen gene co-expression modules were identified and analyzed in relation to honeybee development and stress responses. The darkorange module was found to be associated with low temperature stress, with its genes primarily involved in autophagy-animal, endocytosis and MAPK signaling pathways. Four hub genes were identified within this module, namely, loc726497, loc409791, loc410923, and loc550857, which may contribute to honeybee resistance to low temperature and provide insight into the underlying mechanism. The gene expression patterns of grey60 and black modules were found to correspond to the developmental stages of prepupae and early-pupae, respectively, with the hub genes loc409494, loc725756, loc552457, loc726158, Ip3k and Lcch3 in grey60 module likely involved in brain development, and the hub genes loc410555 in black module potentially related to exoskeleton development. The brown module genes exhibited a distinct pattern of overexpression in mid-pupae specimens, with genes primarily enriched in oxidative phosphorylation, citrate cycle and other pathways, which may be related to the formation of bee flying muscle. No related gene expression module was found for mature larvae stage. These findings provide valuable insights into the developmental process of honeybees at molecular level during the capped brood stage.

Transcriptomic and Chromatin Landscape Analysis Reveals That Involvement of Pituitary Level Transcription Factors Modulate Incubation Behaviors of Magang Geese.

The incubation behavior of geese seriously affects their egg production performance. Studies on incubation behavior have identified functional genes, but the regulatory architecture relationship between functional genes and chromatin accessibility remains poorly understood. Here, we present an integrated analysis of open chromatin profiles and transcriptome to identify the cis-regulatory element and their potential transcription factors involved in regulating incubation behavior in goose pituitary. Assay for transposase-accessible chromatin sequencing (ATAC-seq) revealed that open chromatin regions increased in the pituitary during the transition from incubation behavior to laying. We identified 920 significant differential accessible regions (DARs) in the pituitary. Compared to the laying stage, most DARs had higher chromatin accessibility in the brooding stage. Motif analysis of open DARs showed that the most significant transcription factor (TF) occupied sites predominantly enriched in motifs binding to the RFX family (RFX5, RFX2, and RFX1). While the majority of TF motifs enriched under sites of the nuclear receptor (NR) family (ARE, GRE, and PGR) in closed DARs at the incubation behavior stage. Footprint analysis indicated that the transcription factor RFX family exhibited higher binding on chromatin at the brooding stage. To further elucidate the effect of changes in chromatin accessibility on gene expression levels, a comparison of the transcriptome revealed 279 differentially expressed genes (DEGs). The transcriptome changes were associated with processes of steroid biosynthesis. By integrating ATAC-seq and RNA-seq, few DARs directly affect incubation behavior by regulating the transcription levels of genes. Five DAR-related DEGs were found to be closely related to maintaining the incubation behavior in geese. Footprinting analysis revealed a set of transcription factors (RFX1, RFX2, RFX3, RFX5, BHLHA15, SIX1, and DUX) which displayed the highest activity at the brooding stage. SREBF2 was predicted to be the unique differentially expressed transcription factor whose mRNA level was down-regulated and enriched in hyper-accessible regions of PRL in the broody stage. In the present study, we comprehensively profiled the transcriptome and chromatin accessibility in the pituitary related to incubation behavior. Our findings provided insight into the identification and analysis of regulatory elements in goose incubation behavior. The epigenetic alterations profiled here can help decipher the epigenetic mechanisms that contribute to the regulation of incubation behavior in birds.

Detailed chemical analysis of honey bee (Apis mellifera) worker brood volatile profile from egg to emergence.

Chemical communication is a widely used mode of communication for social insects and has been demonstrated to be involved in many behaviours and physiological processes such as reproduction, nutrition or the fight against parasites and pathogens. In the honey bee, Apis mellifera, the release of chemical compounds by the brood plays a role in worker behaviour, physiology, and foraging activities and colony health as a whole. Several compounds have already been described as brood pheromones, such as components of the brood ester pheromone and (E)-β-ocimene. Several other compounds originating from diseased or varroa-infested brood cells have been described as triggering the hygienic behaviour of workers. So far, studies of brood emissions have focused on specific stages of development and little is known about the emission of volatile organic compounds by the brood. In this study, we investigate the semiochemical profile of worker honey bee brood during its whole developmental cycle, from egg to emergence, with a specific focus on volatile organic compounds. We describe variation in emissions of thirty-two volatile organic compounds between brood stages. We highlight candidate compounds that are particularly abundant in specific stages and discuss their potential biological significance.

Effect of non-essential amino acids (proline and glutamic acid) and sugar polyol (sorbitol) on brood of honey bees

Dietary nutrients provide fuel for the growth and development of insects as well as chemicals for their tissue construction. Apis mellifera L., an important pollinator, collects nectar and pollens from different plants to get their nutritional needs. Honey bees use protein for growth and development and carbohydrates as energy sources. Pollens predominantly contain proline and glutamic acid (non-essential amino acids). This is the first study to evaluate the role of proline, glutamic acid and sorbitol on bee broods. The composition of the diet can optimize the in vitro rearing process. Therefore, we elaborated on the possible impact of these amino acids and sugar alcohol on bee broods. This study aimed to achieve this objective by rearing honey bee larvae under different concentrations of proline, glutamic acid, and sorbitol (1, 4 and 8%), which were supplemented into the standard larval diet. The supplementation of proline helped the quick development of larvae and pupae of honey bees, whereas developmental time only decreased in pupae in the case of glutamic acid. The duration of the total bee brood development was the shortest (20.1 and 20.6 days) on Pro8 and Glu4, respectively. Proline only increased larvae survival (93.8%), whereas glutamic acid did not increase the survival of any brood stage. Pupal and adult weights were also increased with proline and glutamic acid-supplemented diets. Sorbitol did not change the developmental period of the honey bee brood but increased larval survival (93.7%) only at the lowest concentration (Sor1). The small concentration of sorbitol can be used to increase the survival of the honey bee brood. However, a higher concentration (Sor8) of sorbitol reduced the body weight of both pupae and adults. This study predicted that rearing bee brood could be one of the factors for the selectivity of pollen with higher proline and glutamic acid during the foraging of bees.

Intra- and inter-annual variation in body mass of two species of weavers in an Afrotropical environment

ABSTRACT Capsule We describe the effects of sex, daily rainfall and temperature, seasonality, and breeding stage on body mass variation in two species of weaver in a tropical African environment. Aims To investigate the effects of sex, weather conditions, seasonality, and breeding stage on body mass of the Village Weaver Ploceus cucullatus and Northern Red Bishop Euplectes franciscanus in Amurum Forest Reserve, Central Nigeria. Methods Biometric data were extracted from a Constant Effort Sites database of over 15 years and daily rainfall and temperature data were obtained from Jos Metrological Center. We used a general linear mixed model to determine the effects of sex, rainfall, temperature, and season on body mass variation of the two species within and across years, and differences in body mass of females of the two species within and across years with daily rainfall and temperature, and season during the different incubation stages. Results The body mass of males was higher than that of females in both species. Daily rainfall and mean temperature were negatively related to body mass in Village Weavers, while in Northern Red Bishops rainfall was positively related to body mass. In both species, female body mass varied according to brood patch status: female Village Weavers were heavier during the egg-laying stage compared to the non-breeding season; female Northern Red Bishops weighed more at incubation or brooding stages and less during the chick rearing stage when compared to the non-breeding season. The body mass of females did not correlate with daily rainfall and temperature, or season. Conclusions Our results showed the effect of sex on body mass in both species of weaver. The variation in body mass of these species during breeding, and with local weather conditions, suggests how the species manage body mass within a tropical African environment.

Columbian sharp‐tailed grouse female and nest survival in northwestern Colorado

AbstractWildlife management and conservation can be challenging when the demography of a focal species is unknown or limited given that fecundity and adult survival influence population growth. The Columbian sharp‐tailed grouse (Tympanuchus phasianellus columbianus) have been reduced to ≤10% of their former range since the early 1900s. We conducted a 3‐year study (2015–2017) across 4 study sites in northwestern Colorado, USA, to evaluate female hazard and nest survival. We trapped and marked 270 female sharp‐tailed grouse and identified 275 nests for our hazard and survival analyses. Females during the breeding stage of the reproductive season experienced more hazard compared to the nesting and the early and late post‐nesting stages for females without broods. Females experienced a higher degree of hazard during the breeding stage and mortality risk was &gt;3 times higher than the nesting stage, &gt;7 times higher than early post‐nesting (EPN)‐no brood stage, and &gt;5 times higher than the late post‐nesting (LPN)‐unsuccessful stage. Two reproductive season stages (LPN‐successful and EPN‐brood) provided marginal inference. Nest incubation initiation date and nest age best described nest daily survival. Females that initiated incubation of initial nests earlier in the season experienced lower nest daily survival than later in the incubation season. Because female Columbian sharp‐tailed grouse hazard varied among different reproductive season stages, we recommend that wildlife managers develop management actions that reduce hazard during the specific reproductive season stages (i.e., the breeding season). For Columbian sharp‐tailed grouse in Colorado, we recommend that Colorado Parks and Wildlife collaborate with federal farm program agencies to implement a no‐tillage restriction from 1 May through 30 June for active agricultural fields within 2 km of active Columbian sharp‐tailed grouse leks to enhance nest survival.

Brood reduction caused by sibling cannibalism in Isodontia harmandi (Hymenoptera: Sphecidae), a solitary wasp species building communal brood cells.

Sibling rivalry or brood reduction prevailing within bird nests is effectively avoided in solitary aculeate nests because the larvae of wasps and bees usually develop in each brood cell. However, a solitary wasp species, Isodontia harmandi, allows us to study brood reduction in a communal brood cell, where up to a dozen larvae develop in a group relying on prey provisioned by a female wasp. To demonstrate brood reduction in this species, we collected nests at various developmental brood stages from fields for five years (2010–2015). There was a significant decrease in the brood size between the nests sampled at the egg or hatchling stages and those at later stages when analyzing only data excluding nests that were parasitized, attacked by predators, or containing deteriorated prey. In whole brood-rearing experiments, we also confirmed that brood reduction occurred in 30 of 39 nests during larval stages and in 23 nests after cocoon stage. Larval survival was affected positively by total prey weight and negatively by brood size, though cocoon survival was not affected. A third-quarter (76%) of larval death was identified as sibling cannibalism through observation by time-lapse recording on multi-larvae rearing experiments. Therefore, we conclude that brood reduction routinely occurs as a result of sibling cannibalism in I. harmandi. Additionally, as we could not detect any positive effects of clutch size on the amount of provision, female wasps might overproduce offspring due to the unpredictability of available prey resources. Differences in brood size and reduction among sex categories were undetected, except for parental provisions. Thus, sibling cannibalism may efficiently regulate brood size in communal brood cells under prey shortage.

Growth Performance, Bone Development and Phosphorus Metabolism in Chicks Fed Diets Supplemented with Phytase Are Associated with Alterations in Gut Microbiota.

Simple SummaryPhosphorus is a crucial component of nucleic acids, phospholipids, several coenzymes and bone, and plays numerous roles in nutrient metabolism in animals. We investigated the growth performance, bone development, phosphorus metabolism and gut microbiota changes elicited by different phosphorus levels with/without phytase in chicks during the brooding period. Low-phosphorus diets inhibited growth performance and bone development, decreased utilization of phosphorus and altered gut microbial structure and function in the brooding stage of chicks. Inclusion of phytase improved growth performance and bone development and decreased phosphorus emission. The potential mechanisms may be associated with gut microbiota reprogramming.Phosphorus pollution caused by animal husbandry is becoming increasingly problematic, especially where decreasing and non-renewable phosphorus resources are concerned. We investigated the growth performance, bone development, phosphorus metabolism and gut microbiota changes elicited by different phosphorus levels with/without phytase in chicks during the brooding period (1–42 d). Five-hundred-and-forty (540) egg-laying chickens were assigned to six groups (0.13% NPP, 0.29% NPP, 0.45% NPP, 0.13% NPP + P, 0.29% NPP + P and 0.45% NPP + P) according to a factorial design with three non-phytate phosphorus (NPP) levels (0.13, 0.29 and 0.45%) and two phytase (P) dosages (0 and 200 FTU/kg). Chicks fed with the diet with 0.13% NPP had the lowest body weight, average daily gain, shank length, average daily feed intake and highest ratio of feed to gain, while phytase supplementation was able to mitigate the adverse effects of low-phosphorus diets on growth performance. Moreover, phosphorus metabolism was affected by different dietary NPP and phytase levels. Thus, 0.13% NPP significantly reduced serum phosphorus, while phytase supplementation significantly increased serum phosphorus. Notably, phosphorus utilization in the 0.13% NPP group was significantly decreased and the phosphorus excretion ratio was increased. Phytase supplementation significantly improved phosphorus utilization by 43.79% and decreased phosphorus emission in the 0.13% NPP group but not in the 0.29% NPP or the 0.45% NPP group. Remarkably, the alpha diversity of gut microbiota was significantly decreased in the low-phosphorus group, while phytase supplementation increased alpha diversity and improved gut microbial community and function. The LEfSe analysis revealed that several differential genera (e.g., Bacteroides, norank_f__Clostridiales_vadinBB60_group and Eggerthella) were enriched in the different dietary NPP and phytase levels. Furthermore, correlations between differential genera and several crucial phenotypes suggested that the enrichment of beneficial bacteria with different levels of phosphorus and phytase promoted phosphorus utilization in the foregut and hindgut. In summary, low-phosphorus diets inhibited growth performance and bone development, decreased utilization of phosphorus and altered gut microbial structure and function in the brooding stage of chicks. Finally, phytase supplementation improves growth performance and bone development and decreases phosphorus emission, and the potential mechanisms may be associated with the reprogramming of gut microbiota.

Optimization of ideal temperature using Mamdani fuzzy logic alogorithm on tunnel flow type chicken cage for brooding period

Consumption of meat, particularly chicken meat, is increasing in Indonesia year after year, resulting in an increase in chicken meat output. The first step in improving the quality of chicken meat production is to boost success during the brooding stage, with one of the most critical stages being the achievement of the appropriate temperature requirement throughout the brooding period. Good broiler performance will result from uniform cage temperature during brooding. Too-cold temperatures will cause chicks to cuddle close to the heater and be too lethargic to conduct activities such as feeding and drinking. Chickens suffer from stunted growth as a result of this condition. A temperature that is excessively high, on the other hand, will force the chicks to flee the heater and seek a cooler location with better airflow. A fuzzy algorithm is an alternate way for temperature regulation that can maintain the temperature requirement of chicks during brooding. The Mamdani fuzzy approach utilized has the advantage of producing better results than other fuzzy methods. The findings of a temperature management system designed utilizing the Mamdani fuzzy approach with a tunnel flow cage design, a 100-watt bulb heater, two cooling pads, and three fans were able to maintain the appropriate temperature for 14 days in this investigation.

Phosphorus Restriction in Brooding Stage Has Continuous Effects on Growth Performance and Early Laying Performance of Layers.

Simple SummaryPhosphorus plays a critical role in bone and eggshell formation. Dietary phosphorus oversupply depletes non-renewable natural resources and causes environmental concerns in animal husbandry. This study evaluated the effects of phosphorus restriction in the brooding stage and subsequent recovery on growth performance, tibia development and early laying performance of layers. Phosphorus restriction decreases growth performance and bone characters in the brooding stage, and the adverse effects on body weight and early laying performance do not disappear after phosphorus supplementation. These findings give a foundation and new perspective on low phosphorus feeding strategies in the production of layers.This study evaluated the effects of phosphorus restriction in the brooding stage and subsequent recovery on growth performance, tibia development and early laying performance of layers. 360 one-day-old hens were randomly divided into 4 groups with 6 replicates and 15 chicks per replicate. Chicks were fed diets containing 0.13% (L), 0.29% (M), 0.45% (N), 0.59% (H) non-phytate phosphorus (nPP) from 1 to 8 weeks of age. From 9 to 20 weeks of age, the L and N group were divided into two groups fed normal level phosphorus (n, 0.39% nPP) and high-level phosphorus (h, 0.45% nPP) separately, then all the birds were fed a normal diet (0.39% nPP) from 21 to 26 weeks of age. Four treatments were tested: Ln, Lh, Nn, and Nh. The lower body weight, average daily feed intake, tibia length and daily tibial increment were observed in the L group (p < 0.05) and the ratio of feed to gain was significantly increased in the L group at 8 weeks of age (p < 0.05). In addition, the fresh and degreased tibia weight, bone ash, Ca content in the tibia and P content in the ash and tibia were significantly decreased in the L group at 8 weeks of age (p < 0.05). After compensatory processes, there was no significant difference in tibia characters; however, body weight in the Ln group was significantly lower than in the Nn group (p < 0.05) and was significantly lower in the Lh group than the Nn group (p < 0.01) and Nh group (p < 0.05). In addition, the laying rate and average daily egg mass in the Lh group were lower than Nn and Nh (p < 0.05). In conclusion, severe dietary phosphorus restriction impaired growth performance and bone mineralization in the brooding stage. Subsequent phosphorus supplementation could not alleviate this adverse effect on body weight, which continued to affect egg production. These findings give a foundation and new perspective on a low phosphorus feeding strategy in layer production.

Performance evaluation of the parents of the improved backyard poultry germplasm in sub-tropical condition of North Eastern Hill Region of India.

Productivity of traditional backyard poultry in developing countries can be enhanced by introduction of improved germplasm of backyard chicken which is adaptable to diverse ago-climatic condition. The growth and reproductive performance of parents of improved backyard chicken (Vanaraja and Srinidhi) were evaluated under intensive production system in humid sub-tropical region of North East India. We also evaluated the growth performance and mortality in terminal crosses of above parents until 6 weeks of age. At day 0 and at 25 weeks of age, body weight of Srinidhi male parent was significantly (P<0.05) higher than Vanaraja male parent. During brooding stage, mortality was 15.7% in Srinidhi male parent, 14.5% in Vanaraja male parent, 13.9% in Srinidhi female parent, and 8% in Vanaraja female parent. Hen-day egg production (HDEP) of Vanaraja female parent varied from 0.2 at 25 weeks to 54.9% at 54th weeks of age. In Srinidhi female parent, HDEP reached 60% at 35 weeks and peaked 63.9% at 39 weeks of age. Srinidhi female parent has significantly (P<0.05) lower age at first lay. Average annual egg production was significantly (P<0.05) higher in Srinidhi female parent (202 eggs vs. 137 eggs). Egg weight at 25, 30, 35, 40, 45, and 50 week of age was significantly (P<0.05) higher in Vanaraja female parent. Egg shape index and yolk index at 40 weeks of age were significantly (P<0.05) higher in Srinidhi female parent. Fertility of Vanaraja female parent was significantly (P<0.05) lower in winter. In case of Srinidhi female parent, fertility was significantly higher (P<0.05) in winter as compared to summer. In case of terminal crosses, body weight at 6 weeks of age was significantly (P<0.05) higher in Vanaraja as compared to Srinidhi. Cumulative mortality during brooding phase was 9.2 per cent in Vanaraja and 9.6 per cent in Srinidhi. In conclusion, parents of Vanaraja and Srinidhi are suitable and well-adapted birds in humid sub-tropical condition of North East India. These birds could be introduced in the region on large scale for up-scaling of traditional backyard poultry.

Resource selection and movement by northern bobwhite broods varies with age and explains survival.

Resource selection is a dynamic process driven by habitat valuation and risk avoidance in heterogeneous landscapes. Resource selection and movement decisions of individuals may be sensitive to intrinsic factors, such as body condition, and variation in these choices may have consequences on subsequent survival. We evaluated northern bobwhite (Colinus virginianus) brood resource selection patterns to quantify utility of different cover types during the development period using integrated step-selection analysis in a Bayesian hierarchical modeling framework with three brood stages: flightless broods ≤ 14days old, dependent broods 15-35days old, and independent broods over 35days old. Broods showed strongest selection for native grasslands that were burned and grazed at least once in the previous two years, and agricultural fields. Brood mobility improved with age; broods > 35days old travelled farther on average and took daily steps > 200m more frequently than younger broods. Young broods ≤ 14days old did not select for idle native grasslands, while broods > 35days old did select for that cover type. Young broods also selected areas farther from trees compared to older broods. We evaluated the survival consequences of resource selection by comparing patterns in choices of broods that succeeded to choices of broods that failed to survive to 35days. Successful broods chose habitats with more shrub cover and areas farther from trees compared to failed broods. Our results suggest that conservation planning should consider age-specific patterns in habitat use and demographic consequences of habitat choice for greatest effectiveness.

Developmental asynchrony and host species identity predict variability in nestling growth of an obligate brood parasite: a test of the “growth-tuning” hypothesis

Generalist obligate brood parasites are excellent models for studies of developmental plasticity, as they experience a range of social and environmental variation when raised by one of their many hosts. Parasitic Brown-headed Cowbirds (Molothrus ater (Boddaert, 1783)) exhibit host-specific growth rates, yet Cowbird growth rates are not predicted by hosts’ incubation or brooding periods. We tested the novel “growth-tuning” hypothesis which predicts that total asynchrony between Cowbirds’ and hosts’ nesting periods results in faster parasitic growth in nests where host young fledge earlier than Cowbirds. We tested this prediction using previously published and newly added nestling mass data across diverse host species. Total nesting period asynchrony (summed across incubation and brooding stages) predicted Cowbird growth; 8-day-old Cowbirds were heavier in host nests with relatively shorter nesting periods. We further explored the drivers of variation in growth using mass measurements of Cowbirds in Song Sparrow (Melospiza melodia (A. Wilson, 1810)) and Red-winged Blackbird (Agelaius phoeniceus (Linnaeus, 1766)) nests. Our top models included host species (Cowbirds grew faster in Sparrow nests), numbers of nestmates (slowest when raised alone), and sex (males grew faster). These results confirm that multiple social and environmental factors predict directional patterns of developmental plasticity in avian generalist brood parasites.

Evaluation of chemical pesticides for the management of Top Borer (Scirpophaga excerptalis Walker) in sugarcane

An experiment was conducted at research field of National Sugarcane Research Program, Jeetpur, Nepal in 2014 and 2016, to evaluate the efficacy of chemical insecticides against sugarcane top borer (Scirpophaga excerptalis Walker). Nine different treatments viz. Chlorantraniliprole 0.4 G, Cartap hydrochloride 4 G, Fipronil 0.3 G, Carbofuran 3 G (standard check) as soil application and foliar spray of Chlorantraniliprole 18.5 SC, Thiodicarp 75 WP, Spinosad 45 SC, Chlorpyrifos 20 EC (standard check) and one untreated check (control) were used in randomized complete block design with three replications. The top borer susceptible genotype, Co 0238 was planted on February and single application of these insecticides was done on July at brood stage against top borers. The lowest 10.65 and 12.43, 13.68, 14.61, 14.15 percentage of top borer damage was found in foliar application of Chlorantraniliprole @ 35g a.i. /ha followed by Spinosad @ 125g a.i. /ha and soil application of Cartap hydrochloride @ 1500g a.i /ha and foliar application of Thiodicarp @ 1500g a.i. /ha and Fipronil @ 100g a.i. /ha. The infestation percentage reduction over control was found highest in Chlorantraniliprole (69.40%) followed by Spinosad (64.29%) treated plots. Furthermore, the cane yield was highest in Chlorantraniliprole (92.30 mt/ha) and Spinosad (90.06 mt/ha) treated plots than that of other insecticide treated plots. The number of millable canes and cane diameter in the plots among the treatment was found non-significant. Based on the infestation reduction rate, foliar application of the chemical insecticide (Chlorantraniliprole 18.5 SC and Spinosad 45 SC) could be better option for chemical management of sugarcane top borer.&#x0D;

Ecological impacts of an invasive predator are mediated by the reproductive cycle

Predicting the ecological impacts of invasive species is impeded by context-dependencies that can mediate the strength of trophic interactions. Reproductive status is a pervasive context across trophic and taxonomic groups, yet has mostly been neglected in studies of invader impact. The present study examines the influence of the reproductive cycle on predatory impacts of a known damaging invasive freshwater crustacean, Gammarus pulex (Amphipoda), using a comparative functional response approach. Across females that were non-ovigerous, or had immature- or mature-stage embryonic broods, all G. pulex exhibited potentially prey destabilising Type II functional responses towards chironomid larvae. Attack rates were highest by immature embryonic brood stages, and significantly lower by mature embryonic brood stages. Conversely, handling times were consistently lower, and hence maximum feeding rates higher, where broods were present as compared to absent. These predatory patterns may reflect changing resource demands for progeny development across the reproductive cycle, the influence of brood bulk, female moult stage and/or motivational aspects of feeding, such as avoidance of filial cannibalism. Accordingly, many aspects of reproduction may alter the intensity of predatory impacts by invasive species. Future studies considering invader impacts should consider the influence of sex and reproductive status to more holistically quantify and predict population-level invader impacts.

Quantitative proteomic analysis of chicken serum reveals key proteins affecting follicle development during reproductive phase transitions

Avian reproductive behavior is regulated through the neuroendocrine system. The transition from laying to brooding is strictly controlled by the hypothalamus-pituitary-gonadal (HPG) axis. Cross talk on the HPG axis relies on the circulatory system, where the dynamics of serum proteins can be observed during different reproductive phases. Some canonical hormones, such as prolactin and luteinizing hormone, play important roles in the transition through reproductive phases. However, little is known at the whole-proteome level. To discover novel serum proteins, we employed isobaric tags for relative and absolute quantification to assay the serum proteome during different reproductive phases in chicken. We identified a total of 1,235 proteins from chicken serum; 239 of these proteins showed differential expression between the laying and brooding stages, including a low concentration of steroid metabolism-related proteins and a high concentration of calcium signaling-related proteins (fold change ≥1.5 or ≤0.66; P < 0.05). Pathway analysis and protein–protein interaction networks predicated the difference in follicle development between the brooding stage and laying stages and were related to the 14-3-3 protein family, which is associated with oocyte meiosis and maturation. Together, these results provided a proteomics foundation for investigating the dynamic changes taking place in the circulatory system during reproductive phase transition, and also uncovered new insights regarding follicle development that underlie the avian reproductive cycle.