Young Birds Research Articles

Nutritional dynamics in early development of Asian Openbill: A study of hatchling and nestling feeding patterns

Nutrition plays a crucial role in avian development, growth, and health. Inadequate nutrition can have an impact on immune systems and increase susceptibility to diseases. However, there is a paucity of studies that quantify the nutrition provided to young birds. We studied the nutrients delivered to six nests, especially to the hatchling and nestling stages of the Asian Openbill (Anastomus oscitans), using CCTV cameras and spotting scope in Eastern Nepal. Simultaneously, we collected the major food of the Asian Openbill, specifically Filopaludina and Pila spp., and assessed their nutrient content value to estimate the amount of nutrients delivered to the young birds. Asian Openbills feed Filopaludina spp. to hatchlings and both Filopaludina and Pila species to nestlings across all nests. The amount of food supplied to each nest during the nestling stage (272.4 to 386.4 g/day) was approximately three times higher than that during the hatchling stage (87.7 to 128.01 g/day). Energy was primarily derived from protein, followed by fat, and carbohydrate, with variations observed between both nesting stages. Our study provides baseline data on nutrient delivery patterns during two nesting stages of the Asian Openbill in Eastern Nepal, highlighting their adaptability and flexibility in meeting nutritional requirements.

Multitissue transcriptomics demonstrates the systemic physiology of methionine deficiency in broiler chickens

Methionine (Met) supplementation is common practice in broilers to support nutrition, yet there are gaps in the understanding of its role in systemic physiology. Furthermore, several different Met sources are available that may have different physiological effects. This study evaluated the mode of action of Met deficiency (no Met-supplementation) and supplementation (0.25% DL- or L-Met, 0.41% liquid methionine hydroxy analog-free acid (MHA-FA)), and of Met source (DL-, L- or MHA-FA) in broiler chickens, via host transcriptomics. Biological pathway activation modeling was performed to predict the likely phenotypic effects of differentially expressed genes (DEGs) in tissue samples from the jejunum, liver and breast obtained at 10, 21 and 34/35 d of age from three experiments in a combined analysis. Animal performance data showed that Met deficiency reduced BW, daily BW gain, daily feed intake, and breast yield, and increased feed conversion ratio in all experiments (P < 0.05). Effects of Met deficiency on gene expression were least evident in the jejunum and most evident in the liver and breast, as evidenced by the number of DEG and activated pathways. Activated pathways suggested Met deficiency was associated with inhibited protein turnover, gut barrier integrity, and adaptive immunity functions in the jejunum, that predicted reduced breast yield. There was an interaction with age; in Met-deficient birds, there were 333 DEGs in the jejunum of starter vs finisher birds suggesting young birds were more sensitive to Met deficiency than older birds. In the liver, Met deficiency activated pathways associated with lipid turnover, amino acid metabolism, oxidative stress, and the immune system, whereas in breast, it activated pathways involved in metabolic regulation, hemostasis, the neuronal system, and oxidative stress, again predicting a negative impact on breast yield. In the starter phase, supplementation with DL-Met compared to MHA-FA inhibited gamma-aminobutyric acid activity and oxidative stress in breast tissue. When data from all tissues were integrated, increased expression of a liver gene (ENSGALG00000042797) was found to be correlated with the expression of several genes that best explained variation due to the Met deficiency in jejunum and breast muscle. Some of these genes were involved in anti-oxidant systems. Overall, the findings indicate that impaired growth performance due to Met deficiency results from an array of tissue-specific molecular mechanisms in which oxidative stress plays a key systemic role. Young birds are more sensitive to Met-deficiency and DL-Met was a preferential source of Met than L- or MHA-FA during the starter phase.

Influence of bee products on intestinal microbiota formation in healthy birds and birds with candidiasis

Candidamycosis causes significant damage to the poultry industry. Mortality rate in young birds reaches 95100 %. The aim of the study was to optimize formation and intestinal colonization resistance under the influence of biologically active bee products (BABP) and the features of recovery in birds infected with candidamycosis of digestive tract (CDT). Studies were carried out on Japanese meat 10-day-old to 90-day-old quails. All the studied beekeeping products extracts of wax moth, drone homogenate and propolis contribute to the stabilization of the hidden genetically laid down mechanisms of natural intestinal microbiocenosis in healthy quails bred in captivity, without causing damage to the body, restoring the balance of normoflora and opportunistic pathogenic microorganisms to physiological values. However, a constant complex of stressors encountered during bird breeding, associated with the conditions of keeping, feeding, veterinary and zootechnical measures, lead to a significant activation of Candida albicans in large intestine, with the subsequent development of candidiasis of digestive tract, deep dysbacterioses, characterized by increased reproduction and increase in the content of opportunistic pathogenic microorganisms: Candida albicans by 8.34 times, Staphylococcus aureus by 4.37 times, Pseudomonas spp. by 3.29 times; inhibition of reproduction and decrease in the level of normoflora: Lactobacillus spp. by 6.0 times, Bifidobacterium spp. by 7.25 times. The use of extracts of wax moth, drone homogenate and propolis in candidamycosis-i nfected birds contributed to restoration of quail intestinal microbiocenosis, which was manifested by: a) decrease in the level of opportunistic pathogenic Candida albicans by 3.3; 4.61 and 3.97 times; Staphylococcus aureus by 4.0; 7.78 and 4.5 times; Pseudomonas spp. by 3.05; 5.32 and 3.96 times; b) activation and increase of normoflora: Lactobacillus spp. by 6.38; 10.0 and 8.84 times; Bifidobacterium spp. by 5.36; 8.42 and 7.5 times.

Learning shapes the development of migratory behavior

How animals refine migratory behavior over their lifetime (i.e., the ontogeny of migration) is an enduring question with important implications for predicting the adaptive capacity of migrants in a changing world. Yet, our inability to monitor the movements of individuals from early life onward has limited our understanding of the ontogeny of migration. The exploration-refinement hypothesis posits that learning shapes the ontogeny of migration in long-lived species, resulting in greater exploratory behavior early in life followed by more rapid and direct movement during later life. We test the exploration-refinement hypothesis by examining how white storks (Ciconia ciconia) balance energy, time, and information as they develop and refine migratory behavior during the first years of life. Here, we show that young birds reduce energy expenditure during flight while also increasing information gain by exploring new places during migration. As the birds age and gain more experience, older individuals stop exploring new places and instead move more quickly and directly, resulting in greater energy expenditure during migratory flight. During spring migration, individuals innovated novel shortcuts during the transition from early life into adulthood, suggesting a reliance on spatial memory acquired through learning. These incremental refinements in migratory behavior provide support for the importance of individual learning within a lifetime in the ontogeny of long-distance migration.

Layer chicken microbiota: a comprehensive analysis of spatial and temporal dynamics across all major gut sections

BackgroundThe gut microbiota influences chicken health, welfare, and productivity. A diverse and balanced microbiota has been associated with improved growth, efficient feed utilisation, a well-developed immune system, disease resistance, and stress tolerance in chickens. Previous studies on chicken gut microbiota have predominantly focused on broiler chickens and have usually been limited to one or two sections of the digestive system, under controlled research environments, and often sampled at a single time point. To extend these studies, this investigation examined the microbiota of commercially raised layer chickens across all major gut sections of the digestive system and with regular sampling from rearing to the end of production at 80 weeks. The aim was to build a detailed picture of microbiota development across the entire digestive system of layer chickens and study spatial and temporal dynamics.ResultsThe taxonomic composition of gut microbiota differed significantly between birds in the rearing and production stages, indicating a shift after laying onset. Similar microbiota compositions were observed between proventriculus and gizzard, as well as between jejunum and ileum, likely due to their anatomical proximity. Lactobacillus dominated the upper gut in pullets and the lower gut in older birds. The oesophagus had a high proportion of Proteobacteria, including opportunistic pathogens such as Gallibacterium. Relative abundance of Gallibacterium increased after peak production in multiple gut sections. Aeriscardovia was enriched in the late-lay phase compared to younger birds in multiple gut sections. Age influenced microbial richness and diversity in different organs. The upper gut showed decreased diversity over time, possibly influenced by dietary changes, while the lower gut, specifically cecum and colon, displayed increased richness as birds matured. However, age-related changes were inconsistent across all organs, suggesting the influence of organ-specific factors in microbiota maturation.ConclusionAddressing a gap in previous research, this study explored the microbiota across all major gut sections and tracked their dynamics from rearing to the end of the production cycle in commercially raised layer chickens. This study provides a comprehensive understanding of microbiota structure and development which help to develop targeted strategies to optimise gut health and overall productivity in poultry production.

UV-induced feather color change reflects its porphyrin content.

Pigmentary coloration is widespread in animals. Its evolutionary and ecological features are often attributed to the property of predominant pigments; therefore, most research has focused on predominant pigments such as carotenoids in carotenoid-based coloration. However, coloration results from predominant pigments and many other minority pigments, and the importance of the latter is overlooked. Here, we focused on porphyrin, an "uncommon" pigment found in bird feathers, and investigated its importance in the context of feather color changes in the barn swallow Hirundo rustica. We found that the "pheomelanin-based coloration" of the barn swallow faded after the irradiation of UV light, and this effect was particularly strong in the feathers of young swallows (nestlings and fledglings, here). We also found that it is not the predominant pigment, pheomelanin, but protoporphyrin IX pigment that showed the same pattern of depigmentation after the irradiation of UV light, particularly in the feathers of young swallows. In fact, the abovementioned age-dependent feather color change was statistically explained by the amount of porphyrin in the feathers. The current study demonstrates that a minority pigment, porphyrin, explains within-season dynamic color change, an ecological feature of feather coloration. The porphyrin-mediated rapid color change would benefit young birds, in which feather coloration affects the parental food allocation during a few weeks before independence, but not later. Future studies should not ignore these minor but essential pigments and their evolutionary and ecological functions.

MITRAL REGURGITATION IN SADDLE-BILLED STORKS (EPHIPPIORHYNCHUS SENEGALENSIS) IN HUMAN CARE: DIAGNOSIS, ECHOCARDIOGRAPHIC MEASUREMENTS, AND MANAGEMENT.

The asymptomatic and slow progressive nature of cardiopathies represents a risk to the welfare of avian species in human care. Diagnosis and treatment of cardiac disease in birds pose a challenge due to unique anatomic and physiologic characteristics. Comprehensive cardiac assessments with diagnostic tools such as echocardiography, color-Doppler, the biomarker cardiac troponin I (cTn1), and cholesterol serum concentrations have been utilized in different bird species with varying success. Saddle-billed storks (Ephippiorhynchus senegalensis) have been maintained in human care for over 80 yrs and several institutions have noted heart murmurs and cardiomegaly. Despite these findings, peer-reviewed literature describing cardiopathies is lacking for this species. This case series documents the identification of mitral valve regurgitation in saddle-billed storks in a breeding center. Transcoelomic echocardiography using a ventromedial approach with a two-chambered view and color Doppler was utilized. Echocardiographic measurements were taken and compared 1 yr later in most of the birds. There was left atrial enlargement and worsened mitral regurgitation in one geriatric patient, and no progression of the disease in two young birds. Serum samples showed that cTn1 had different concentrations depending on the severity of the disease, whereas cholesterol was within reference range for all birds. Treatment with digoxin and pimobendan was recommended in one bird, serum concentrations of digoxin were tested in a 6-mon span, results were within therapeutic range, and there were no overt adverse effects. There was a suspected genetic component in this population, as four of the five birds with confirmed mitral regurgitation were related.

Sex Identification of the Sun Conure (Aratinga solstitialis) Using Calamus Based on Polymerase Chain Reaction

Sex identification of Sun Conures (Aratinga solstitialis) is crucial for breeding and preservation, as well as increasing sun conure populations. These birds are sexually monomorphic. Therefore, Determination between male and female carried out by their morphology examination. The Polymerase Chain Reaction (PCR) method, utilizing molecular-based technology, was employed to determine the sex of Aratinga solstitialis in this study. The P2 and P8 primers were utilized in this method, which has been deemed suitable and accurate for sex identification through calamus samples. The research focused on two 28-month-old Aratinga solstitialis birds. Calamus samples were collected and subjected to PCR amplification using the extracted calamus. The resulting PCR products were then visualized using electrophoresis with a 1% agarose gel. In the electrophoresis photo, the presence of two bands indicated a female specimen, whereas a single band indicated a male specimen. The result of the gel electrophoresis research showed that both of the Aratinga solstitialis were male with one band of each bird on ranged from 300-400 base pairs. The result show that the Polymerase Chain Reaction method in terms for sex identification on monomorphic birds, especially Aratinga solstitialis birds is very effective to differentiate the sex of young birds and the adults.

Avian Infectious Bronchitis Virus: Molecular Detection in Southwestern Ethiopia Chickens.

Infectious bronchitis virus (IBV) is a significant threat to poultry worldwide, but its status in Ethiopia remains understudied. Thus, this study aimed to detect the virus and associated risk factors in South West Ethiopia. Ninety oropharyngeal swab samples were purposively collected from symptomatic chickens located in Jimma town, Seqa Chekorsa, and Tiro Afeta woredas of the Jimma zone between November 2021 and April 2022 to detect IBV virus by using RT-PCR. A side-by-side questionnaire was administered to assess risk factors. Total RNA was extracted, reverse transcription polymerase chain reaction (RT-PCR) was conducted, and products were visualized under UV light. The overall proportion of IBV was 16.6% (15/90). No statistical association was observed between any of the animal risk factors and the detection of the virus (P=0.57, 0.586, and 1). However, the proportion of birds infected by the virus was higher in males, exotic breeds, and adults compared to females, local breeds, and young birds. Similarly, none of the management risk factors had a significantly different effect on virus detection (P=0.25, 0.09, 0.088, and 0.726). However, improper carcass disposal (OR = 0.43, 95% CI: 0.13-1.4), lack of veterinary services (OR = 2.7, 95% CI: 0.8-8.3), and the presence of wild birds/rodents (OR = 4.4, 95% CI: 0.88-22.3) were associated with increased IBV risk but not cleaning of feeders/drinkers (OR = 1.1, 95% CI: 0.2-4.8). These findings underscore the need for enhanced biosecurity practices and further research to implement informed IBV control strategies in Ethiopia.

Severe decline in abundance of Cyathostoma lari, a parasite of the nasal and orbital sinuses of gulls, at their central European nesting grounds.

Cyathostoma lari is a parasite of the nasal and orbital sinuses of gulls and other hosts in Europe and Canada. Here, we provide an overview of previously published data on the prevalence and infection intensity of C. lari in gulls. Furthermore, based on our data, we analyze the spatiotemporal trends in the prevalence and intensity of infection by C. lari in Chroicocephalus ridibundus in Czechia (central Europe; data from 1964 to 2014) and compare them with those obtained from five species of gulls in Karelia (Northwest Russia; data from 2012-2020). Based on our preliminary observations, we hypothesized that C. lari is subject to a decline in certain regions, but this decline is not necessarily applicable throughout its distribution range. We found that the C. lari population crashed in specific parts of its distribution range. The reasons are unknown, but the observed population changes correspond with the diet switch of their core host in Czechia, C. ridibundus. We previously observed a diet switch in Czech C. ridibundus from earthworms (intermediate hosts of C. lari) to other types of food. This diet switch affected both young and adult birds. Nevertheless, it may not necessarily affect populations in other regions, where they depend less on earthworms collected from agrocenoses affected by agrochemicals and trampling. Correspondingly, we found that these changes were limited only to regions where the gulls feed (or fed) on arable fields. In Karelia, where arable fields are scarce, gulls likely continue to feed on earthworms and still display high infection rates by C. lari. Therefore, C. lari, a parasite of the nasal and orbital sinuses of gulls, nearly disappeared from their central European nesting grounds but is still present in better-preserved parts of its distribution range.

ЭФФЕКТИВНОСТЬ ПРИМЕНЕНИЯ КАРОТИНСОДЕРЖАЩИХ ПРЕПАРАТОВ В РАЦИОНАХ КУР-НЕСУШЕК

Deficiency of carotene and vitamin A leads to various diseases of young birds, a sharp decrease in the productivity of adult birds. As you know, beta-carotene, unlike vitamin A, does not have toxic properties, it protects the liver from hepatotropic poisons and gives poultry products a good marketable appearance. This paper presents the results of studies on the influence of carotene- containing preparations caroflavin and carophyllin on the body of laying hens and the marketable quality of eggs. We evaluated the productivity of laying hens. After the use of caroflavin and carophyllin, the egg production of hens increased by 2,9% and 3,7%, the amount of carotenoids in the egg yolk increased by 25,2 and 33%, vitamin E – by 23,5 and 64,7%, and vitamin A – by 34,8 and 52,2% compared to the control.

Digestible calcium equivalency of phytase and nutrient utilization of broiler chickens fed graded levels of limestone or phytase during the starter phase

The current study aimed to quantify the digestible Calcium (Ca) equivalency of a new phytase (HiPhoriusTM) in broiler chickens. A total of 1,152 male Cobb 500 broiler chickens were used in an experiment in which 8 diets consisting of graded levels of Ca supplied with limestone or graded levels of the phytase were fed. The 8 dietary treatments were based on a corn-soybean meal diet containing 5.1 g/kg of Ca and 5.1 g/kg of phosphorus (P) as negative control (NC); the NC + 1.3, 2.6, or 3.9 g/kg of Ca from limestone; and the NC + 500, 1000, 2000, or 4000 FYT/kg of phytase. Birds were fed the experimental diets for 3 d (from d 7 to 10) or 14 d (from d 7 to 21) to determine apparent ileal digestibility (AID) and apparent total tract retention (ATTR) of dry matter (DM), CP, Ca, and P. In the 10-d-old birds, increasing the levels of Ca decreased the AID of P and Ca (linear, P < 0.05). Increasing the levels of phytase quadratically improved (P < 0.05) the AID of Ca and P. The AID of DM and CP in the younger birds quadratically increased (P < 0.05) as the levels of Ca increased. There were linear and quadratic effects (P < 0.05) of increasing phytase level for the AID of DM and a linear effect (P < 0.05) for the AID of CP. In the 21-d-old birds, increasing Ca levels resulted in a linear decrease (P < 0.05) in the AID of CP and P, and a quadratic decrease (P < 0.05) in the ATTR of CP. Increasing phytase levels linearly and quadratically (P < 0.05) improved the AID and ATTR of CP, P, and the ATTR of Ca. The analyzed phytase activity in the diets supplemented with phytase ranged from 1,520 to 7,661 FYT/kg. The digestible Ca equivalence for dietary phytase at 1,520 to 7,661 FYT/kg ranged from 1.55 to 2.02 g/kg in the 10-d-old birds fed for 3 d and from 0.52 to 0.64 g/kg in 21-d-old birds fed for 14 d. The results showed the reduction in Ca level that could be accommodated by phytase supplementation, which is markedly different between the younger and older birds. Feeding duration influenced the impact of phytase supplementation on Ca and P digestibility, with better efficacy of phytase observed in the 10-d-old birds fed for 3 d. Also, the results showed the extra-phosphoric effects of phytase on the utilization of other essential nutrients such as protein and Ca.

Microbial carriage of Dermanyssus gallinae ticks

The effectiveness of the development of the poultry industry depends on the veterinary well-being of farms, in particular, in relation to invasive diseases. One of the most widespread ectoparasites among poultry farms is the gamasic mite Dermanyssus gallinae. As a result of tick parasitism, the egg and meat productivity of chickens decreases, often the death of young birds. Dermanyssus ticks are hematophagous and can be carriers of pathogens of infectious diseases of chickens, including zooanthroponosis. The research method was used to investigate the presence of specific pathogens carried by Dermanyssus gallinae. In laboratory conditions, inoculation was carried out from the homogenate of ticks isolated from chickens and objects of poultry premises on nutrient media (blood agar, yolk-salt agar, Saburo, Simmons, Endo, Ploskirev, bismuth-sulfite agar). As a result of bacteriological studies of Dermanyssus gallinae isolated from different substrates, microorganisms belonging to three species and four genera were isolated – Staphylococcus spp., Enterococcus faecalis, Klebsiella pneumoniae, Escherichia coli. Dermanyssus ticks isolated from chickens were carriers of only two genera and one species of microorganisms – Staphylococcus spp. (37.5 %) and Euterococcus facalis (31.3 %). Moreover, monoisolates (77.8 %) were most often isolated from ticks, the majority of which were Staphylococcus spp. (44.5 %), less – Enterococcus faecalis (33.3 %). Bacterial associations were rarely identified (22.2 %). Dermanyssus ticks, isolated from the objects of the poultry house environment, turned out to be carriers of a larger spectrum of microorganisms, where Staphylococcus spp. were more often isolated (100 %) and Escherichia coli (43.8 %), less often – Klebsiella pneumoniae (37.5 %) and Enterococcus faecalis (18.8 %). The isolates were dominated by associations of microorganisms (62.5 %). The monoisolate was represented only by Staphylococcus spp. (37.5 %). The data obtained by us regarding the isolated microorganisms further expand the vector role of D. gallinae, proving their danger for poultry enterprises producing food products. In general, dermanyssiosis can seriously affect the health of chickens both because of ectoparasites – hematophages, and because of the ability to transmit pathogens.

Current Symptoms and Pathological Changes of Bursa Fabricius from Commercial Farming Broilers Led to Infectious Bursal Disease

Infectious Bursal Disease (IBD) or Gumboro is caused by the IBD virus of the Birnaviridae family. The disease is acute and highly contagious in young birds. The virus infection causes severe damage to the lymphoid organs i.e. bursa Fabricius leading to immunosuppression. The disease morbidity may reach 100%, while the mortality varies from 20 to 100%, causing high economic losses. Infectious Bursal Disease has remained significant threat although vaccination has been applied. This study aimed to determine the current typical pathological changes in the bursa Fabricius of commercial broilers showing IBD symptoms. The samples were obtained from commercial broiler farms in Sragen, Wonogiri, Batang, and Sleman. Gross lesion examination showed enlargement of the bursa Fabricius with gelatinous material on the serosal surface, oedema with fluid accumulation in the lumen, hemorrhages of the serosal surface, atrophy, and caseous exudate in the lumen. Histopathologic changes of acute IBD include hemorrhages, congestion, lymphocyte necrosis, accumulation of fibrin, oedematous and heterophils infiltration in the interfollicular tissues. Microscopic changes in chronic IBD (5-7 days post infection IBDV) including follicular atrophy, lymphocyte necrosis, vacuolization of the follicle, and proliferation of fibroblast and connective tissue in the interfollicular space. In conclusion, the notable pathological change description of bursa Fabricius in suspected acute is gross lesion (swelling and edema, thickened and enlarged plica bursa Fabricius, hemorraghe), microscopic lesion (congestion, hemorraghe, heterophil infiltration) or chronically IBD infection in broiler chicken was gross lesion (atrophy bursa Fabricius, atrophy and excudate casouse in the lumen bursa Fabricius), microscopic lesion (lymphocyte necrosis, vacuolization of bursa Fabricius follicles, proliferation of fibroblasts and interfollicular connective tissue).

Splayed Leg in Birds: Diagnosis, Therapy, and Prevention

Splayed leg is a condition where the legs are stretched outwards or sideways from their normal position under the body which is often suffered by young birds. This disorder is usually left untreated, because it is considered as a permanent disability condition that cannot be treated without examining the cause. Some of the splayed legs in chicks can be improved by treating both their legs in the correct position. Early diagnosis of splayed leg and continued appropriate therapy is needed so that the condition of the foot can be restored to normal. Incorrect diagnosis and therapy will cause the bird's feet to become permanently disabled, so the bird will suffer for the rest of its life. The diagnosis and treatment of splayed leg cases have been developed with varying results. The purpose of this review is to evaluate the diagnosis, therapy, and prevention of the occurrence of splayed legs in birds, which can be used as a reference to improve bird welfare.

최근 10년(2013-2022년)간 다도해해상국립공원 흑산도의 조류 도래 현황

In Heuksan Island in Dadohaehaesang National Park in the southwest of the Korean Peninsula, we studied to find out the current status of bird banding for 10 years from 2013 to 2022, the minimum period of stay, and the minimum life expectancy in the stopover sites by species. We catched to a total of 56,778 of 194 species, and 98.4% of Passeriformes. The proportion of males was high with 25.0% for females and 28.0% for males, 48.6% for young birds and 32.4% for adult birds. 6.7% of all were re-captured in the same area, followed by 24% of the Zosterops japonicus, 15% of the Emberiza spodocephala, and 8% of the Parus minor and Turdus pallidus. There was a difference in the minimum length of stay between species in the Emberizidae, Emberiza pallasi stayed 1.8 days (n=222) and of the Emberiza pusilla stayed 8.6 days (n=52).

Colony attendance and moult pattern of Cory's Shearwaters (Calonectris borealis) differing in breeding status and age

Migratory birds must fit three costly life‐history events within the annual cycle, reproduction, moult and migration, to minimize their overlap and maximize survival and breeding success. However, some seabirds, such as Cory's Shearwater Calonectris borealis, overlap body moult and breeding, with flight feather renewal occurring in late chick‐rearing. In contrast, the moult patterns of non‐breeding adult (sabbatical) and immature Cory's Shearwaters, which also attend the colony during the breeding season, remain poorly understood. Furthermore, the potential implications of life‐stage and breeding status trade‐offs on moult status and colony attendance in non‐breeders has rarely been investigated. Surveying different areas within one colony between June and September 2013 and 2014, we studied the age and breeding status composition of birds attending the breeding colony and scored moult of their body (breast and upper‐neck), wing and tail feathers. We found that in addition to breeders (n = 165), 57.6% of the birds (n = 389) attending the colony were 4‐ to 10‐year‐old immatures (n = 132) and adult sabbatical shearwaters (n = 92). Sabbaticals and 8‐ to 10‐year‐old immatures (n = 28) were present at the colony during incubation, whereas only three sabbatical birds and no 8‐ to 10‐year‐old immatures were captured in late chick‐rearing. Conversely, 4‐ to 7‐year‐old immatures arrived later in the season but were still present in late chick‐rearing. Sabbatical and 8‐ to 10‐year‐old immatures were moulting body feathers at the same time as adult breeders, whereas, among 4‐ to 7‐year‐old immatures, older birds moulted earlier than younger birds. A larger proportion of sabbatical birds were replacing tail feathers compared with adult breeders. However, there was no evidence that sabbaticals or 8‐ to 10‐year‐old immatures differed in wing moult from adult breeders until August. Overall, our study shows that colony attendance by non‐breeding adults and immatures is widespread in this population. The synchronous moult schedule of flight and body feathers across age groups at different life‐history stages may suggest that this aspect of moult is controlled by environmental conditions.

Long‐term conservation efforts at flyway scale can halt the population decline in a globally endangered migratory raptor

AbstractMany threatened species require ongoing management, which is often funded through short project cycles. Evaluating whether the management is effective in protecting a species is important to inform future management investments. For migratory species, management may affect only part of a species' annual cycle, and reversing a population decline is challenging to achieve and demonstrate. Here, we evaluate whether conservation management projects funded by the European LIFE programme to safeguard a migratory vulture population achieved their major objective of stabilizing the target breeding population. Between 2012 and 2022, an international alliance of conservation organizations implemented multiple actions to reduce poisoning, direct persecution, and electrocution and collision with power lines along the Eastern Mediterranean flyway. We monitored breeding territories of the Balkan population of the globally endangered Egyptian Vulture Neophron percnopterus between 2006 and 2022, and tracked 60 young birds with GPS transmitters since 2010. We used these data to examine whether population growth rate and survival probability had increased since project implementation. The mean annual survival probability of adult territorial birds increased by 1.9% since 2014 from 0.937 to 0.955, and the monthly survival probability of wild juvenile birds increased by 9.7% from 0.833 to 0.914 since 2018. The population growth rate across the Balkans increased by 6.9% from 0.939 before 2018 to 1.005 since 2018. This indicates that the Egyptian Vulture population has remained stable for the past 5 years (2018–2022), but at a population size that is only half (105 adult territorial birds in 2022) than at the beginning of the time series (204 in 2006). We caution that ongoing management along the flyway and reinforcement are required to ensure that the Egyptian Vulture population on the Balkans can recover, but we show that flyway‐scale collaboration of direct conservation actions can have lasting benefits for migratory species.

New Behavioral Handling Test Reveals Temperament Differences in Native Japanese Chickens.

It is well known in the poultry industry that fear and stress experienced during the handling of day-old chicks in commercial hatcheries can have long-lasting effects on their behavior later in life. These hatchery-related stresses are more intense and complex than those encountered in traditional behavioral tests. Consequently, a single behavioral test may not be sufficient to measure hatchery stresses and chicken temperament. In this study, we developed a new behavioral handling test for day-old chickens, which incorporated concepts from established behavioral tests used with both young and adult birds. The new test assessed 10 behavioral traits, including vocalization frequency and responses to human interaction. It was conducted on 96 two-day-old chicks from seven breeds of native Japanese and Western chickens. The results of the principal component analysis classified chicken temperaments into three distinct categories: bustle, aggression, and timidity. Using these categories, the seven breeds were classified into five groups, each with distinct temperaments. This study highlights the reliability and value of the new handling test in characterizing the temperaments of various chicken breeds and provides insights into the complex behaviors of chickens.

A Snapshot on the Genomic Epidemiology of Turkey Reovirus Infections, Hungary.

Reovirus infections in turkeys are associated with arthritis and lameness. Viral genome sequence data are scarce, which makes an accurate description of the viral evolution and epidemiology difficult. In this study, we isolated and characterized turkey reoviruses from Hungary. The isolates were identified in 2016; these isolates were compared with earlier Hungarian turkey reovirus strains and turkey reoviruses isolated in the 2010s in the United States. Gene-wise sequence and phylogenetic analyses identified the cell-receptor binding protein and the main neutralization antigen, σC, to be the most conserved. The most genetically diverse gene was another surface antigen coding gene, μB. This gene was shown to undergo frequent reassortment among chicken and turkey origin reoviruses. Additional reassortment events were found primarily within members of the homologous turkey reovirus clade. Our data showed evidence for low variability among strains isolated from independent outbreaks, a finding that suggests a common source of turkey reoviruses in Hungarian turkey flocks. Given that commercial vaccines are not available, identification of the source of these founder virus strains would permit a more efficient prevention of disease outbreaks before young birds are settled to fattening facilities.