Coturnix Coturnix Research Articles

Brain gene expression reveals pathways underlying nocturnal migratory restlessness

Migration is one of the most extreme and energy demanding life history strategies to have evolved in the animal kingdom. In birds, champions of long-distance migrations, the seasonal emergence of the migratory phenotype is characterised by rapid physiological and metabolic remodelling, including substantial accumulation of fat stores and increases in nocturnality. The molecular underpinnings and brain adaptations to seasonal migrations remain poorly understood. Here, we exposed Common quails (Coturnix coturnix) to controlled changes in day length to simulate southward autumn migration, and then blocked the photoperiod until birds entered the non-migratory wintering phase. We first performed de novo RNA-Sequencing from selected brain samples (hypothalamus) collected from birds at a standardised time at night, either in a migratory state (when restlessness was highest and at their body mass peak), or in a non-migratory state and conducted differential gene expression and functional pathways analyses. We found that the migratory state was associated with up-regulation of a few, yet functionally well defined, gene expression networks implicated in fat trafficking, protein and carbohydrate metabolism. Further analyses that focused on candidate genes (apolipoprotein H or APOH, lysosomal associated membrane protein-2 or LAMP2) from samples collected during the day or night across the entire study population suggested differences in the expression of these genes depending on the time of the day with the largest expression levels being found in the migratory birds sampled at night. We also found that expression of APOH was positively associated with levels of nocturnal activity in the migratory birds; such an association was absent within the non-migratory birds. Our results provide novel experimental evidence revealing that hypothalamic changes in expression of apolipoprotein pathways, which regulate the circulatory transport of lipids, are likely key regulatory activators of nocturnal migratory movements. Our study paves the way for performing deeper functional investigations on seasonal molecular remodelling underlying the development of the migratory phenotype.

Mitogenomic Insights into the Evolution, Divergence Time, and Ancestral Ranges of Coturnix Quails.

The Old-World quails, Coturnix coturnix (common quail) and Coturnix japonica (Japanese quail), are morphologically similar yet occupy distinct geographic ranges. This study aimed to elucidate their evolutionary trajectory and ancestral distribution patterns through a thorough analysis of their mitochondrial genomes. Mitogenomic analysis revealed high structural conservation, identical translational mechanisms, and similar evolutionary pressures in both species. Selection analysis revealed significant evidence of positive selection across the Coturnix lineage for the nad4 gene tree owing to environmental changes and acclimatization requirements during its evolutionary history. Divergence time estimations imply that diversification among Coturnix species occurred in the mid-Miocene (13.89 Ma), and their current distributions were primarily shaped by dispersal rather than global vicariance events. Phylogenetic analysis indicates a close relationship between C. coturnix and C. japonica, with divergence estimated at 2.25 Ma during the Pleistocene epoch. Ancestral range reconstructions indicate that the ancestors of the Coturnix clade were distributed over the Oriental region. C. coturnix subsequently dispersed to Eurasia and Africa, and C. japonica to eastern Asia. We hypothesize that the current geographic distributions of C. coturnix and C. japonica result from their unique dispersal strategies, developed to evade interspecific territoriality and influenced by the Tibetan Plateau's geographic constraints. This study advances our understanding of the biogeographic and evolutionary processes leading to the diversification of C. coturnix and C. japonica, laying important groundwork for further research on this genus.

Infestations with nematode species in the common pheasant (Phasianus Colchicus l.) and quails (Cotrunix Cotrunix l.) from the Republic of Moldova

The aim of this study was to evaluate the level of infestation with nematodes in birds of hunting interest (Pheasants, quails). During the years 2020-2023, from various natural and anthropogenic biotopes of the Republic of Moldova, from pheasants (Phasianus colchicus L.) and quails (Cotrunix cotrunix L.), 164 and 152 samples, were collected. Their infestation with 7 nematode species (Capillaria caudinflata, Capillaria annulata, Syngamus tracheia, Heterakis isolonche, Ascaridia galli, Heterakis gallinarum, Trichostrongylus tenuis), which belong to 5 families and 5 genera, were established. In pheasants, an increased prevalence of infestation with the: Ascaridia galli - 44,3%, Heterakis isolonche – 31,2% and Heterakis gallinarum – 16,2% species was established. In quails predominates infestation with Ascaridia galli species (53.2%) and Heterakis gallinarum (28.7%). The established species are geohelminths, also common in domestic gallinaceae.

Network and structural analysis of quail mucins with expression pattern of mucin 1 and mucin 4 in the intestines of the Iraqi common quail (Coturnix coturnix).

In avian and other species, mucins (MUCs) play a crucial role in the gastrointestinal tract (GIT), and constitute a large group of O-glycosylated glycoproteins, are glycoconjugate proteins. MUCs present in two forms: (1) membrane-attached on cell surfaces to repel external threats and (2) detachable, gel-forming proteins in the soluble form. In quail GIT, the specific types of MUCs that are expressed remain largely unknown. We investigated the expression of MUC1 and MUC4 MUCs in the GIT of Iraqi common quails and conducted network and structural analyses of all known MUC types across quail breeds. Histological and gene expression analyses of MUC1 and MUC4 were conducted using fresh small intestine and large intestine samples from 10 quails. Using the STRING Database, Chimera software, and PrankWeb-ligand binding site prediction tool, network and structural analyses of all reported types of quail MUCs were conducted. Most intestinal MUCs in quails were acidic, with few neutral MUCs detectable through Alcian blue and periodic acid-schiff stains. Acidic MUCs were more expressed in the duodenum, ileum, cecum, and colon, whereas neutral MUCs were more expressed in the jejunum. MUC1 and MUC4 messenger RNA expression was significantly higher in the jejunum and colon than in the duodenum and ileum. The analysis of the network revealed that MUC 1, 15, 16, and 24 formed homologous networks, while MUC 2, 4, 5, and 6 formed heterologous networks. Specific MUC combinations, including MUC5A-MUC6, MUC5A-MUC5B, and MUC5B-MUC6, show higher intermolecular hydrogen bond formation affinity. MUC15, MUC16, and MUC24 showed minimal interaction with other MUC types. Among the analyzed MUCs, MUC5B, and MUC6 had the highest probability for binding, while MUC2, MUC4, and MUC5A showed lower probabilities despite greater numbers of binding sites. This study's results offer significant insights into quails' MUCs' composition, expression, network interactions, and binding sites, advancing knowledge of MUC-related processes in gastrointestinal physiology and their potential connection to gastrointestinal diseases.

Comparative study of the ciliary body and iris morphology in the anterior eye chamber of five different vertebrate classes.

One crucial component of the optical system is the ciliary body (CB). This body secretes the aqueous humour, which is essential to maintain the internal eye pressure as well as the clearness of the lens and cornea. The histological study was designed to provide the morphological differences of CB and iris in the anterior eye chambers of the following vertebrate classes: fish (grass carp), amphibians (Arabian toad), reptiles (semiaquatic turtle, fan-footed gecko, ocellated skink, Egyptian spiny-tailed lizard, Arabian horned viper), birds (common pigeon, common quail, common kestrel), and mammals (BALB/c mouse, rabbit, golden hamster, desert hedgehog, lesser Egyptian jerboa, Egyptian fruit bat). The results showed distinct morphological appearances of the CB and iris in each species, ranging from fish to mammals. The present comparative study concluded that the morphological structure of the CB and iris is the adaptation of species to either their lifestyle or survival in specific habitats.

The effects of cities on quail (Coturnix coturnix) migration: a disturbing story of population connectivity, health, and ecography

The increasing impact of human activities on ecosystems is provoking a profound and dangerous effect, particularly in wildlife. Examining the historical migration patterns of quail (Coturnix coturnix) offers a compelling case study to demonstrate the repercussions of human actions on biodiversity. Urbanization trends, where people gravitate toward mega-urban areas, amplify this effect. The proliferation of artificial urban ecosystems extends its influence across every biome, as human reliance on infrastructure and food sources alters ecological dynamics extensively. We examine European quail migrations pre- and post-World War II and in the present day. Our study concentrates on the Italian peninsula, investigating the historical and contemporary recovery of ringed quail populations. To comprehend changes in quail migration, we utilize trajectory analysis, open statistical data, and linear generalized models. We found that while human population and economic growth have shown a linear increase, quail recovery rates exhibit a U-shaped trajectory, and cereal and legume production displays an inverse U-shaped pattern. Generalized linear models have unveiled the significant influence of several key factors—time periods, cereal and legume production, and human demographics—on quail recovery rates. These factors closely correlate with the levels of urbanization observed across these timeframes. These insights underscore the profound impact of expanding human populations and the rise of mega-urbanization on ecosystem dynamics and services. As our planet becomes more urbanized, the pressure on ecosystems intensifies, highlighting the urgent need for concerted efforts directed toward conserving and revitalizing ecosystem integrity. Simultaneously, manage the needs and demands of burgeoning mega-urban areas. Achieving this balance is pivotal to ensuring sustainable coexistence between urban improvement and the preservation of our natural environment.

Controlled expression of avian pre-migratory fattening influences indices of innate immunity.

While immunity is frequently dampened when birds engage in strenuous migratory flights, whether and how immunity changes during the rapid accumulation of energy stores in preparation for migration remains largely unknown. Here we induced pre-migratory fattening through controlled changes of daylight in common quails (Coturnix coturnix) and regularly assessed changes in three markers of constitutive innate immunity (leukocyte coping capacity or LCC, hemagglutination and hemolysis titres) and measures of body composition (lean and fat mass). All the three markers showed similar changes over the pre-migratory fattening process. LCC responses, hemagglutination titres, and hemolysis titres, were on average higher in the mid-fattening phase compared to the peak-fattening phase, when values were similar to those observed prior the start of pre-migratory fattening. At mid-fattening, we found that the birds that showed a larger accumulation of fat mass (as % of body mass) had lower LCC peak responses and hemolysis titres. Reversibly, at mid-fattening, we also found that the birds that kept a higher proportion of lean mass (as % of body mass) had the highest LCC peaks. Our results indicate that migratory birds undergo changes in immune indices (over 8 weeks) as they accumulate energy stores for migration and propose that this could be due to competing or trade-off processes between metabolic remodelling and innate immune system function.

Liver and kidney damage in quail embryos hatched from eggs sprayed once with chlorpyrifos during artificial incubation.

Birds have enough conditions to be used as bioindicators for the presence of environmental contaminants. Notably, chlorpyrifos (CPF) remains extensively employed in Argentina, particularly in fruit plantations and livestock settings This study aimed to assess the potential impacts of CPF on common quail (Coturnix coturnix) embryos through external eggshell application during key embryonic stages (days 1, 4, and 14). Concentrations equivalent to those used in fruit applications, 5× and 10 × (38.4, 192, and 384µg/egg), were employed. A 48% commercial formulation of CPF (Pirfos - Icona®) was utilized. An increase in embryonic deaths, as well as a statistical association between the degree of liver or kidney lesions and CPF concentrations was observed. The results suggest that CPF can induce embryotoxic effects with a single exposure to quail embryos and compromise the viability of the organisms. The study suggests a potential exposure risk for embryos through contact with the insecticide on the eggshell's exterior.

Retracted: The Comparative Pharmaco- and Histokinetics of the Therapeutic Dose of Estradiol Valerate and Bromocriptine in Common Quails.

[This retracts the article DOI: 10.1155/2022/5482895.].

Molecular prevalence, phylogeny and hematological impact of Toxoplasma gondii and Plasmodium spp. in common quails from Punjab, Pakistan.

This study investigates the molecular prevalence and phylogenetic characteristics of two prominent blood-borne pathogens, Toxoplasma gondii (T. gondii) and Plasmodium spp., in common quails (Coturnix coturnix) sampled from both wild (N = 236) and farmed (N = 197) populations across four districts (Layyah, Dera Ghazi Khan, Lahore, and Multan) in Punjab, Pakistan, during the hunting seasons from 2021 to 2023. Additionally, the impact of these pathogens on the complete blood count (CBC) of the hosts is examined. Out of 433 quails tested, 25 (5.8%) exhibited amplification of the internal transcribed spacer (ITS-1) gene for T. gondii, while 15 (3.5%) showed amplification of the Cytochrome b gene for Plasmodium spp. A risk factor analysis indicated that the prevalence of both pathogens was not confined to specific sampling sites or bird sexes (P > 0.05). District-wise analysis highlighted that hens were more susceptible to both T. gondii and Plasmodium spp. infections than cocks. Wild quails exhibited a higher susceptibility to T. gondii compared to farmed birds. Significant CBC variations were recorded in infected birds as compared to uninfected ones. BLAST analysis of generated sequences has confirmed the identity of recovered PCR amplicons as T. gondii and Plasmodium relictum. Phylogenetic analysis revealed that Pakistani isolates clustered with those reported from various countries globally. This study provides the first documentation of T. gondii and Plasmodium sp. infections in Pakistani quails, underscoring the need for detailed investigations across different regions to enhance our understanding of infection rates and the zoonotic potential of these parasites.

Planos nutricionais e temperatura ambiente nas curvas de crescimento de codornas japonesas

ABSTRACT: This study estimated the growth of body, carcass, primal cuts, edible offal, and feathers of Japanese quail reared in two thermal environments, receiving three nutritional plans, from one to 39 days of age. A total of 576 one-day-old female chicks (Coturnix japonica) with an average initial weight of 7.51±0.75g/bird were evaluated in a completely randomized design with a 3 × 2 factorial arrangement (three nutritional plans × two temperatures). The animals were housed in two climatic chambers, at 25 ºC and 35 ºC, using 12 replications with eight birds per experimental unit. Nutritional plans (NP) were as follows: NP1: one diet from 1-21days and another from 22-39 days; NP2: one diet from 1-14 days and another from 15-39 days; and NP3: a single diet from 1-39 days. The growth curves and growth rates of body, carcass, primal cuts, feathers, and edible offal were evaluated using the Gompertz mathematical model. Quail fed NP3 showed higher growth curves and rates for body, carcass, drumstick +thigh, and feather. There was an effect on maturity rate, which was lowest in quail housed at 35 ºC. Among the animals kept at 25 ºC, the group fed NP3 exhibited the highest growth rate and breast weight. The nutritional plan consisting of a single diet offered from 1 to 39 days, formulated based on the tables for Japanese and European quail, is the most suitable for estimating the growth curves (Gompertz model) of Japanese quail housed at 25 ºC or 35 ºC.

Diversity, Abundance, and Distribution of Avifauna in District Jhang, Pakistan

The present study was conducted from March 2021 to February 2022 in the Thal desert and Trimmu barrage of district Jhang located in the Punjab province of Pakistan to find out the diversity, abundance, and distribution of birds. The point count method was used for the Trimmu barrage, and the line transect method was used for the collection of data in the Thal desert area. We recorded 31,696 individuals belonging to 67 species of birds from two distinct types of habitats (Thal desert and Trimmu barrage) of district Jhang. Among these species, 39 species were residents, 18 species were winter visitors, 9 species were summer breeders, and a single species (Terek sandpiper) was a passage migrant. Highly significant differences ( X 2 = 14979.7 , df = 11 , and P < 0.01 ) were observed in the abundance of birds between both habitats on every month. From the Thal desert area, 12,905 individuals belonging to 45 species were identified while 18,791 individuals from 58 bird species were observed in the Trimmu barrage, with 36 bird species among 67 species being common at both habitats. The most dominant species of the Trimmu barrage were the common pochard, little grebe, common coot, cattle egret, gadwall, little egret, red-wattled lapwing, and common teal. On the other hand, the Indian roller, common quail, cattle egret, common myna, and Indian kite were found to be the most common species in the Thal desert. The most notable feature of the present study is the identification of Xenus cinereus (Terek sandpiper) and Ammomanes phoenicura (rufous-tailed lark) in district Jhang as both species had no previous record in the study area. The Trimmu barrage was the more diverse and abundant site compared to the Thal desert as it provides both terrestrial and aquatic habitats for birds. The study determined that more varieties in the habitat and thermal changes affect the diversity, abundance, and distribution of birds.

A study of egg quality characteristics for two Asiatic (Coturnix japonica) and two European (Coturnix coturnix) quail lines

The present study was carried out at the Dept. of Animal Production, College of Agricultural Engineering Sciences, University of Duhok, Kurdistan Region, Iraq. A total of 64 female quails from four lines involved two European (White and Dark Ukrainian) and two Asiatic (White and Dark Local) aged 56 days old, were equally distributed into four trial groups containing 16 birds for each. The aim was to investigate both external and internal egg quality characteristics. The following traits were measured; weights, lengths (high) and diameters of egg, yolk, albumen and shell; and the indices of shape, yolk and albumen were computed; also, Haugh units and percentages of yolk, albumen and shell were calculated. The results revealed the significant (p<0.01) superiority of European quails on Asiatic ones in egg quality characteristics; also, the white Ukrainian line appeared a significant difference (p<0.01) compared to the rest lines for egg weight and yolk percentage; however, Haugh units resulted in almost the same values for both European lines which surpassed significantly (p<0.01) both Asiatic ones; the same trend was found for albumen index. Most correlation coefficients between egg quality characteristics were significant (p<0.01), and the highest coefficient was between Haugh units and albumen index (0.89); therefore, the regression analysis derived an effective equation between them for future prediction with a high coefficient of variation (R2= 0.8). In conclusion, Ukrainian-European quail surpassed in its egg quality Asiatic ones, and Haugh units as a major quality indicator can be predicted from the albumen index for quail’s eggs.

Effect of atrazine on testicular toxicity involves accommodative disorder of xenobiotic metabolizing enzymes system and testosterone synthesis in European quail (Coturnix coturnix)

Due to the wide use of atrazine (ATR), the concern has increased regarding the negative impact of ATR on reproduction. Nevertheless, the reproductive effects caused by different exposure concentrations and the severity of toxic damage are poorly understood. In organisms, ATR is metabolized and degraded through phase II enzyme systems, and changes in cytochrome P450 (CYP) enzymes may have a regulatory role in the harm of ATR. However, less information is available on the induction of CYPs by ATR in avian organisms, and even less on its effects on the testis. Birds are exposed to ATR mainly through food residues and contaminated water, the purpose of this study was to examine reproductive toxicity by different exposure concentrations and elaborate metabolic disorders caused by ATR in European quail (Coturnix coturnix). In this study, the quail were given ATR at 50 mg/kg, 250 mg/kg and 500 mg/kg by oral gavage for 45 days, and the testicular weight coefficients, histopathology and ultrastructure of testes, primary biochemical functions, sex steroid hormones, critical protein levels in the testosterone synthesis pathway, the expression of genes involved CYPs, gonad axis and nuclear receptors expression were investigated. Altogether, testicular coefficient decreased significantly in the high-dose group (1.22%) compared with the control group (3.03%) after 45 days of ATR exposure, and ATR is a potent CYP disruptor that acts through the NXRs and steroid receptor subfamily (APND, CAR, ERND and ERα) without a dose-dependent manner. Notably, ATR interfered with the homeostasis of hormones by triggering the expression of hormones on the gonad axis (LH and E2). These results suggest that exposure to ATR can cause testicular toxicity involving accommodative disorder of phase II enzyme and testosterone synthesis in European quail.

Nutritional, Productive, and Qualitative Characteristics of European Quails Fed with Diets Containing Lipid Sources of Plant and Animal Origin.

The objective of this study was to investigate the impact of alternative lipid sources on nutrient metabolism, performance, carcass characteristics, and meat quality in European quails. Trial 1 determined the energy values and nutrient metabolizability of non-conventional lipid sources. Six treatments (control, soybean oil, conventional corn oil, distilled corn oil, poultry fat, and beef tallow) were randomly assigned with 10 replicates per treatment. Trial 2 evaluated animal performance, carcass characteristics, and meat quality using a randomized design with five treatments and 10 replicates each. Statistical analysis showed no significant difference in apparent metabolizable energy corrected by nitrogen (AMEn) and coefficients of metabolizability (CM%) among the lipid sources. The AMEn values found were 8554 for soybean oil, 7701 for corn, 7937 for distilled corn oil, 7906 for poultry fat, and 7776 for beef tallow (kcal/kg). The CM values were 88.01% for soybean oil, 79.01% for corn oil, 84.10% for distilled corn oil, 81.43% for poultry fat, and 79.28% for beef tallow. The inclusion of lipid sources of plant and animal origin in the diet of 7-35-day old meat quails did not influence performance or carcass and cut characteristics. The inclusion of distilled corn oil increased carcass yield and influenced skin and meat color parameters. AMEn values varied for each lipid source. The inclusion of distilled corn oil positively influenced skin and meat color as well as carcass yield in quails.

Calcium anacardate and its association with citric acid in diets for meat-type breeding quails.

The purpose of this study was to evaluate the effects of using calcium anacardate (CaA) as a source of anacardic acid and its association with citric acid (CA) in diets for breeding quails on the performance, the egg quality, incubation parameters, and progeny performance. Were used 540 quails European quails (Coturnix coturnix coturnix) that were 21 weeks old, housed in laying cages based on a completely randomized design, with nine treatments and six replications of 10 quails per parcel, with each experimental unit having eight females and two males. The following additions to the diet were evaluated: 1, no addition (control diet); 2, 0.25% CaA; 3, 0.25% CaA and 0.25% CA; 4, 0.50% CaA; 5, 0.50% CaA and 0.25% CA; 6, 0.50% CaA and 0.50% CA; 7, 0.75% CaA; 8, 0.75% CaA and 0.25% CA; and 9, 0.75% CaA and 0.50% CA. The treatments had no significant effects on the performance of the breeding quails, incubation parameters, and progeny performance. For egg quality, there was only an effect on yolk lipid oxidation, which was lower for eggs from quails fed the diets containing 0.50% CaA and 0.25% CA, 0.50% CaA and 0.50% CA, or 0.75% CaA alone, when compared with the control group. Considering that including CaA with or without CA in diets for breeding quails only affected yolk lipid oxidation, it can be recommend including 0.50% CaA and 0.25% CA or 0.75% CaA alone to mitigate oxidative damage in the yolk of fertile eggs.

Effect of environment, and seaweed (Sagassum sp) in the feed on the physiological behavior and performance of European quail

This study aimed to evaluate the influence of the inclusion of marine macroalgae bran of the species Sargassum sp at increasing levels (0; 2.5; 5 and 7.5 %) on the productive performance and physiological responses of European quail (Coturnix coturnix coturnix), in two types of environments. A total of 480 European quail chicks (Coturnix coturnix coturnix) were used, distributed in an entirely randomized design, with four levels of bran inclusion (0.0; 2.5; 5.0, and 7.5 %), 6 repetitions with 10 birds in each experimental plot. Water consumption was higher and feed intake was lower in the climatic chamber in all phases, presenting regression and interaction effects for both environments as a function of sargassum bran inclusion. Thus, feed conversion and weight gain were also influenced and similar to the feed and water intake results. For the physiological variables, no interactions between the environments were identified as a function of sargassum bran inclusion in any of the phases. However, there were significant differences between the environments. In the first phase, the respiratory rate variable was higher in the climatic chamber and there was no significant difference in the other phases. It is recommended the inclusion of up to 7.5% of sargassum bran in the diet of European quail in all phases, without compromising their productive performance and maintaining the physiological variables within the normal range in environments similar to those simulated in the open housing. However, under heat stress conditions, the quail are compromised, and the inclusion did not have the effect of maintaining the performance of the birds.

Will passive acoustic monitoring make result‐based payments more attractive? A cost comparison with human observation for farmland bird monitoring

AbstractResult‐based payments (RBPs) reward land users for conservation outcomes and are a promising alternative to standard payments, which are targeted at specific land use measures. A major barrier to the implementation of RBPs, particularly for the conservation of mobile species, is the substantial monitoring cost. Passive acoustic monitoring may offer promising opportunities for low‐cost monitoring as an alternative to human observation. We develop a costing framework for comparing human observation and passive acoustic monitoring and apply it to a hypothetical RBP scheme for farmland bird conservation. We consider three different monitoring scenarios: daytime monitoring for the whinchat and the ortolan bunting, nighttime monitoring for the gray partridge and the common quail, and day‐and‐night monitoring for all four species. We also examine the effect of changes in relevant parameters (such as participating area, travel distance and required monitoring time) on the cost comparison. Our results show that passive acoustic monitoring is still more expensive than human observation for daytime monitoring. In contrast, passive acoustic monitoring has a cost advantage for nighttime as well as day‐and‐nighttime monitoring in all considered scenarios.

Marine macroalgae as an alternative in the feeding of broiler quails in an environment of thermal stress

The objective of this research was to evaluate the productive performance, carcass quality, and intestinal biometry of European quails (Coturnix coturnix coturnix), kept under cyclic heat stress (air temperature of 32.5°C±0.5) receiving a ration with different concentrations (0, 2.5, 5, and 7.5%) of seaweed meal of Sargassum sp. A total of 240 quails were used, distributed in a completely randomized design with 4 levels of bran inclusion, 6 replications, and 10 birds per experimental unit. An analysis of variance (ANOVA) was performed, and the means were compared by Tukey's test with 5% probability and subjected to regression by PROC REG of SAS® (2002). No similarity was observed in water and feed consumption between treatments. There was a significant difference in most of the variables studied, with a significant difference only occurring in the dorsum, gizzard, and large intestine. Therefore, it is recommended to include up to 7.5% of sargassum bran in the diet of European quails kept under a 12-h heat cycle (32°C±0.5).

Description of natal down of the ostrich (Struthio camelus) and comparison with common quail (Coturnix coturnix): Developmental and evolutionary implications.

Natal down is a feather stage that differs in both form and function from the definitive feathers of adult birds. It has a simpler structure that has been speculated to be similar to the body coverings of non-avian dinosaurs. However, inference of the evolution of natal down has been limited by our understanding of its structural variation in extant birds. Most descriptive work has focused on neognathous birds, limiting our knowledge of the full diversity of feathers in extant taxa. Here, we describe the natal down of a post-hatch ostrich (Struthio camelus) and compare it to that of a post-hatch quail (Coturnix coturnix). We confirm the presence of featherless spaces (apteria) in S. camelus and the lack of barbules on the tips of natal down in both species. We also find differences between dorsal and ventral natal down structures, such as barbule density in S. camelus and the extent of the bare portion of the barb in both species. Surprisingly, we do not find that the neoptiles of either species follow the ideal morphologies for increasing insulation. Finally, we hypothesize that the different barb types present in S. camelus natal down result from a large addition of new barb ridges during development, which is not known except in feathers with a rachis. These results have implications for our understanding of how structure informs function and development in understudied feather types, such as those shared by non-avian dinosaurs.