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1.
BMC Genomics ; 25(1): 331, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565992

RESUMO

BACKGROUND: The pig (Sus Scrofa) is one of the oldest domesticated livestock species that has undergone extensive improvement through modern breeding. European breeds have advantages in lean meat development and highly-productive body type, whereas Asian breeds possess extraordinary fat deposition and reproductive performance. Consequently, Eurasian breeds have been extensively used to develop modern commercial breeds for fast-growing and high prolificacy. However, limited by the sequencing technology, the genome architecture of some nascent developed breeds and the human-mediated impact on their genomes are still unknown. RESULTS: Through whole-genome analysis of 178 individuals from an Asian locally developed pig breed, Beijing Black pig, and its two ancestors from two different continents, we found the pervasive inconsistent gene trees and species trees across the genome of Beijing Black pig, which suggests its introgressive hybrid origin. Interestingly, we discovered that this developed breed has more genetic relationships with European pigs and an unexpected introgression from Asian pigs to this breed, which indicated that human-mediated introgression could form the porcine genome architecture in a completely different type compared to native introgression. We identified 554 genomic regions occupied 63.30 Mb with signals of introgression from the Asian ancestry to Beijing Black pig, and the genes in these regions enriched in pathways associated with meat quality, fertility, and disease-resistant. Additionally, a proportion of 7.77% of genomic regions were recognized as regions that have been under selection. Moreover, combined with the results of a genome-wide association study for meat quality traits in the 1537 Beijing Black pig population, two important candidate genes related to meat quality traits were identified. DNAJC6 is related to intramuscular fat content and fat deposition, and RUFY4 is related to meat pH and tenderness. CONCLUSIONS: Our research provides insight for analyzing the origins of nascent developed breeds and genome-wide selection remaining in the developed breeds mediated by humans during modern breeding.


Assuntos
Introgressão Genética , Estudo de Associação Genômica Ampla , Humanos , Animais , Suínos/genética , Genoma , Genômica/métodos , Cruzamento , Polimorfismo de Nucleotídeo Único , Sus scrofa/genética , Seleção Genética
2.
PLoS One ; 19(4): e0299954, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38635514

RESUMO

For migratory birds, events happening during any period of their annual cycle can have strong carry-over effects on the subsequent periods. The strength of carry-over effects between non-breeding and breeding grounds can be shaped by the degree of migratory connectivity: whether or not individuals that breed together also migrate and/or spend the non-breeding season together. We assessed the annual cycle of the White-crested Elaenia (Elaenia albiceps chilensis), the longest-distance migrant flycatcher within South America, which breeds in Patagonia and spends the non-breeding season as far north as Amazonia. Using light-level geolocators, we tracked the annual movements of elaenias breeding on southern Patagonia and compared it with movements of elaenias breeding in northern Patagonia (1,365 km north) using Movebank Repository data. We found that elaenias breeding in southern Patagonia successively used two separate non-breeding regions while in their Brazilian non-breeding grounds, as already found for elaenias breeding in the northern Patagonia site. Elaenias breeding in both northern and southern Patagonia also showed high spread in their non-breeding grounds, high non-breeding overlap among individuals from both breeding sites, and similar migration phenology, all of which suggests weak migratory connectivity for this species. Elucidating the annual cycle of this species, with particular emphasis on females and juveniles, still requires further research across a wide expanse of South America. This information will be critical to understanding and possibly predicting this species' response to climate change and rapid land-use changes.


Assuntos
Passeriformes , Aves Canoras , Humanos , Animais , Feminino , Migração Animal/fisiologia , Brasil , Cruzamento , Estações do Ano
3.
PLoS Biol ; 22(4): e3002584, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38626215

RESUMO

In animals, reproductive performance typically improves over time early in life. Several ultimate and proximate mechanisms may contribute to such an age-related improvement and these mechanisms can act in a relative or in an absolute sense. Low performance of young individuals may be the consequence of a comparison or competition with older individuals (relative), or it may be due to specific traits of young individuals and be unrelated to the presence of older competitors (absolute). Here, we perform a test to disentangle whether the effect of age class (yearling or older) on male extra-pair siring success is relative or absolute. Male age is the most consistent predictor of male extra-pair siring success across bird species, yet the mechanisms underlying this pattern are not well understood. Low extra-pair siring success of yearling males may be a consequence of the presence of older ("adult") males (hypothesis 1), because adult males are more successful in intra- and intersexual interactions or because females prefer to copulate with adult males when available (relative preference). Alternatively, low extra-pair siring success of yearlings may be independent of the presence of adult males (hypothesis 2), for example, if yearling males on average invest less in extra-pair behavior or if females avoid them as extra-pair mates, independent of the availability of older males (absolute preference). To distinguish between these 2 hypotheses, we experimentally manipulated the age structure of a nest-box-breeding population of blue tits (Cyanistes caeruleus) by removing almost all adult males, and compared patterns of extra-pair paternity in the experimental year with those from the preceding 15 "control" years. Removal of adult males resulted in a substantial increase in the extra-pair siring success of yearling males compared to the "control" years, but did not affect the population-level frequency of extra-pair paternity or its spatial patterns. Our results provide clear evidence that extra-pair siring success of yearlings can increase and that it depends on the presence of older males in the population, indicating a relative effect of age on reproductive performance. These results suggest that older males outcompete yearling males in direct or indirect interactions, in sperm competition or as a result of differences in attractiveness to females.


Assuntos
Comportamento Sexual Animal , Aves Canoras , Humanos , Animais , Feminino , Masculino , Sêmen , Reprodução , Cruzamento
4.
Sci Rep ; 14(1): 8396, 2024 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600096

RESUMO

Disease-causing variants have been identified for less than 20% of suspected equine genetic diseases. Whole genome sequencing (WGS) allows rapid identification of rare disease causal variants. However, interpreting the clinical variant consequence is confounded by the number of predicted deleterious variants that healthy individuals carry (predicted genetic burden). Estimation of the predicted genetic burden and baseline frequencies of known deleterious or phenotype associated variants within and across the major horse breeds have not been performed. We used WGS of 605 horses across 48 breeds to identify 32,818,945 variants, demonstrate a high predicted genetic burden (median 730 variants/horse, interquartile range: 613-829), show breed differences in predicted genetic burden across 12 target breeds, and estimate the high frequencies of some previously reported disease variants. This large-scale variant catalog for a major and highly athletic domestic animal species will enhance its ability to serve as a model for human phenotypes and improves our ability to discover the bases for important equine phenotypes.


Assuntos
Cruzamento , Genoma , Cavalos/genética , Animais , Humanos , Fenótipo , Polimorfismo de Nucleotídeo Único
5.
Oecologia ; 204(3): 675-688, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38459994

RESUMO

Anthropogenic activities generate increasing disturbance in wildlife especially in extreme environments where species have to cope with rapid environmental changes. In Antarctica, while studies on human disturbance have mostly focused on stress response through physiological and behavioral changes, local variability in population dynamics has been addressed more scarcely. In addition, the mechanisms by which breeding communities are affected around research stations remain unclear. Our study aims at pointing out the fine-scale impact of human infrastructures on the spatial variability in Adélie penguin (Pygoscelis adeliae) colonies dynamics. Taking 24 years of population monitoring, we modeled colony breeding success and growth rate in response to both anthropic and land-based environmental variables. Building density around colonies was the second most important variable explaining spatial variability in breeding success after distance from skua nests, the main predators of penguins on land. Building density was positively associated with penguins breeding success. We discuss how buildings may protect penguins from avian predation and environmental conditions. The drivers of colony growth rate included topographical variables and the distance to human infrastructures. A strong correlation between 1-year lagged growth rate and colony breeding success was coherent with the use of public information by penguins to select their initial breeding site. Overall, our study brings new insights about the relative contribution and ecological implications of human presence on the local population dynamics of a sentinel species in Antarctica.


Assuntos
Spheniscidae , Animais , Humanos , Spheniscidae/fisiologia , Dinâmica Populacional , Cruzamento , Regiões Antárticas
6.
Proc Biol Sci ; 291(2018): 20240314, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38471549

RESUMO

North Atlantic right whales are Critically Endangered and declining, with entanglements in fishing gear a key contributor to their decline. Entanglement events can result in lethal and sub-lethal (i.e. increased energetic demands and reduced foraging ability) impacts, with the latter influencing critical life-history states, such as reproduction. Using a multi-event framework, we developed a Bayesian mark-recapture model to investigate the influence of entanglement severity on survival and recruitment for female right whales. We used information from 199 known-aged females sighted between 1977 and 2018, combined with known entanglements of varying severity that were classified as minor, moderate or severe. Severe entanglements resulted in an average decline in survival of 27% for experienced non-breeders, 9% for breeders and 26% for pre-breeding females compared with other entanglements and unentangled individuals. Surviving individuals with severe entanglements had low transitional probabilities to breeders, but surprisingly, individuals with minor entanglements had the lowest transitional probabilities, contrary to expectations underpinning current management actions. Management actions are needed to address the lethal and sub-lethal impacts of entanglements, regardless of severity classification.


Assuntos
Reprodução , Baleias , Humanos , Animais , Feminino , Idoso , Teorema de Bayes , Cruzamento , Oceano Atlântico
7.
Parasite ; 31: 16, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38530209

RESUMO

The prevalence of asymptomatic leishmaniasis in dogs and their owners in the main endemic areas of France has not been studied to date. The objective of this study was to quantify asymptomatic Leishmania infantum infection in southeast France in healthy people and their dogs using molecular and serological screening techniques. We examined the presence of parasitic DNA using specific PCR targeting kinetoplast DNA (kDNA) and specific antibodies by serology (ELISA for dogs and Western blot for humans) among immunocompetent residents and their dogs in the Alpes-Maritimes. Results from 343 humans and 607 dogs were included. 46.9% (n = 161/343) of humans and 18.3% (n = 111/607) of dogs were PCR positive; 40.2% of humans (n = 138/343) and 9.9% of dogs (n = 60/607) were serology positive. Altogether, 66.2% of humans (n = 227) and 25.7% of dogs (n = 156) had positive serologies and/or positive PCR test results. Short-haired dogs were more frequently infected (71.8%, n = 112) than long-haired dogs (12.2%, n = 19) (p = 0.043). Dogs seemed to be more susceptible to asymptomatic infection according to their breed types (higher infection rates in scenthounds, gun dogs and herding dogs) (p = 0.04). The highest proportion of dogs and human asymptomatic infections was found in the Vence Region, corresponding to 28.2% (n = 20/71) of dogs and 70.5% (n = 31/44) of humans (4.5/100,000 people). In conclusion, the percentage of infections in asymptomatic humans is higher than in asymptomatic dogs in the studied endemic area. It is questionable whether asymptomatic infection in humans constitutes a risk factor for dogs.


Title: Infection asymptomatique à Leishmania infantum chez les chiens et propriétaires de chiens dans une zone endémique du sud-est de la France. Abstract: La prévalence de la leishmaniose asymptomatique chez les chiens et leurs propriétaires dans les principales zones d'endémie françaises n'a pas été étudiée à ce jour. L'objectif de cette étude était de quantifier l'infection asymptomatique à Leishmania infantum dans le sud-est de la France chez des personnes saines et leurs chiens à l'aide de techniques de dépistage moléculaire et sérologique. Nous avons examiné chez des résidents immunocompétents et leurs chiens dans les Alpes-Maritimes la présence d'ADN parasitaire par PCR spécifique ciblant l'ADN du kinétoplaste (ADNk) et d'anticorps spécifiques par sérologie (ELISA pour le chien et Western Blot pour l'homme). Les résultats de 343 humains et 607 chiens ont été inclus; 46,9 % (n = 161/343) des humains et 18,3 % (n = 111/607) des chiens étaient positifs à la PCR et 40,2 % des humains (n = 138/343) et 9,9 % des chiens (n = 60/607) avaient une sérologie positive. Au total, 66,2 % des humains (n = 227) et 25,7 % des chiens (n = 156) avaient des sérologies positives et/ou des résultats de tests PCR positifs. Les chiens à poils courts étaient plus fréquemment infectés (71,8 %, n = 112) que les chiens à poils longs (12,2 %, n = 19) (p = 0,043). Les chiens semblaient plus sensibles à l'infection asymptomatique selon leurs races (taux supérieurs chez les chiens de chasse et chiens de berger) (p = 0,04). La plus forte proportion d'infections asymptomatiques chez les chiens et les humains a été observée dans la Région de Vence, correspondant à 28,2 % (n = 20/71) des chiens et 70,5 % (n = 31/44) des humains (4,5/100 000). personnes). En conclusion, le pourcentage d'infections chez les humains asymptomatiques est plus élevé que chez les chiens asymptomatiques dans la zone d'endémie étudiée. On peut se demander si une infection asymptomatique chez l'homme constitue un facteur de risque pour les chiens.


Assuntos
Leishmania infantum , Humanos , Cães , Animais , Leishmania infantum/genética , Infecções Assintomáticas/epidemiologia , Western Blotting , Cruzamento , DNA de Cinetoplasto , França/epidemiologia
8.
Sci Rep ; 14(1): 6976, 2024 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-38521842

RESUMO

Smart hospitals are poised to greatly enhance life quality by offering persistent health monitoring capabilities. Remote healthcare and surgery, which are highly dependent on low latency, have seen a transformative improvement with the advent of 5G technology. This has facilitated a new breed of healthcare services, including monitoring and remote surgical procedures. The enhanced features of 5G, such as Enhanced Mobile Broadband (eMBB) and Ultra-Reliable Low Latency Communications (URLLC), have enabled the development of advanced healthcare systems. These systems reduce the need for direct patient contact in hospitals, which is especially pertinent as 5G becomes more widespread. This research presents novel hybrid detection algorithms, specifically QR decomposition with M-algorithm maximum likelihood-minimum mean square error (QRM-MLD-MMSE) and QRM-MLD-ZF (zero forcing), for use in Massive MIMO (M-MIMO) technology. These methods aim to decrease the latency in MIMO-based Non-Orthogonal Multiple Access (NOMA) waveforms while ensuring optimal bit error rate (BER) performance. We conducted simulations to evaluate parameters like BER and power spectral density (PSD) over Rician and Rayleigh channels using both the proposed hybrid and standard algorithms. The study concludes that our hybrid algorithms significantly enhance BER and PSD with lower complexity, marking a substantial improvement in 5G communication for smart healthcare applications.


Assuntos
Instalações de Saúde , Hospitais , Humanos , Algoritmos , Cruzamento , Comunicação
9.
Biol Lett ; 20(3): 20230376, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38442871

RESUMO

Floaters are sexually mature individuals that are not able to reproduce by defending breeding resources. Floaters often visit active nests, probably to gather public information or to compete for a nesting site. We tested the hypothesis that floaters preferentially prospect nests in which they have a better chance of taking over, and that they do so by assessing the owners' resource holding potential (RHP). We manipulated the flight capacity of male and female breeders in a population of spotless starlings (Sturnus unicolor) by clipping two flight feathers per wing before egg laying, thus increasing their wing-load and likely impairing their condition. We subsequently monitored breeder and floater activity by means of transponder readers during the nestling period. We found that nests owned by wing-clipped males were visited by a greater number of male floaters than control nests. This effect was absent in the case of wing-clipped females. The number of male floaters also increased with increasing nestling age and number of parental visits. The experiment shows that male floaters preferentially prospect nests in which the owner shows a reduced RHP, a strategy that likely allows them to evict weak owners and take over their nests for future reproductive attempts.


Assuntos
Estorninhos , Humanos , Animais , Feminino , Masculino , Cruzamento , Plumas , Oviposição , Reprodução
10.
Food Microbiol ; 120: 104485, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431330

RESUMO

This study aimed to elucidate the distribution, transmission, and cross-contamination of Clostridium perfringens during the breeding and milking process from dairy farms. The prevalence of 22.3% (301/1351) yielded 494 C. perfringens isolates; all isolates were type A, except for one type D, and 69.8% (345/494) of the isolates carried atyp. cpb2 and only 0.6% (3/494) of the isolates carried cons. cpb2. C. perfringens detected throughout the whole process but without type F. 150 isolates were classified into 94 pulsed-field gel electrophoresis (PFGE) genotypes; among them, six clusters contained 34 PFGE genotypes with 58.0% isolates which revealed epidemic correlation and genetic diversity; four PFGE genotypes (PT57, PT9, PT61, and PT8) were the predominant genotypes. The isolates from different farms demonstrated high homology. Our study confirmed that C. perfringens demonstrated broad cross-contamination from nipples and hides of dairy cattle, followed by personnel and tools and air-introduced raw milk during the milking process. In conclusion, raw milk could serve as a medium for the transmission of C. perfringens, which could result in human food poisoning. Monitoring and controlling several points of cross-contamination during the milking process are essential as is implementing stringent hygiene measures to prevent further spread and reduce the risk of C. perfringens infection.


Assuntos
Infecções por Clostridium , Clostridium perfringens , Animais , Bovinos , Humanos , Clostridium perfringens/genética , Infecções por Clostridium/epidemiologia , Infecções por Clostridium/veterinária , Leite , Prevalência , Fazendas , Genótipo , Cruzamento
11.
Heredity (Edinb) ; 132(4): 211-220, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38472424

RESUMO

Inbreeding can reduce offspring fitness and has substantial implications for the genetic diversity and long-term viability of populations. In social cooperative canids, inbreeding is conditioned by the geographic proximity between opposite-sex kin outside natal groups and the presence of related individuals in neighbouring groups. Consequently, challenges in moving into other regions where the species is present can also affect inbreeding rates. These can be particularly problematic in areas of high human density, where movement can be restricted, even for highly vagile species. In this study, we investigate the socio-ecological dynamics of Iberian wolf packs in the human-dominated landscape of Alto Minho, in northwest Portugal, where wolves exhibit a high prevalence of short-distance dispersal and limited gene flow with neighbouring regions. We hypothesise that mating occurs regardless of relatedness, resulting in recurrent inbreeding due to high kin encounter rates. Using data from a 10-year non-invasive genetic monitoring programme and a combination of relatedness estimates and genealogical reconstructions, we describe genetic diversity, mate choice, and dispersal strategies among Alto Minho packs. In contrast with expectations, our findings reveal relatedness-based mate choice, low kin encounter rates, and a reduced number of inbreeding events. We observed a high prevalence of philopatry, particularly among female breeders, with the most common breeding strategy involving the pairing of a philopatric female with an unrelated immigrant male. Overall, wolves were not inbred, and temporal changes in genetic diversity were not significant. Our findings are discussed, considering the demographic trend of wolves in Alto Minho and its human-dominated landscape.


Assuntos
Endogamia , Lobos , Humanos , Animais , Masculino , Feminino , Lobos/genética , Cruzamento , Reprodução/genética , Fluxo Gênico , Comportamento Sexual Animal
12.
Genet Sel Evol ; 56(1): 15, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424504

RESUMO

BACKGROUND: Genetic merit, or breeding values as referred to in livestock and crop breeding programs, is one of the keys to the successful selection of animals in commercial farming systems. The developments in statistical methods during the twentieth century and single nucleotide polymorphism (SNP) chip technologies in the twenty-first century have revolutionized agricultural production, by allowing highly accurate predictions of breeding values for selection candidates at a very early age. Nonetheless, for many breeding populations, realized accuracies of predicted breeding values (PBV) remain below the theoretical maximum, even when the reference population is sufficiently large, and SNPs included in the model are in sufficient linkage disequilibrium (LD) with the quantitative trait locus (QTL). This is particularly noticeable over generations, as we observe the so-called erosion of the effects of SNPs due to recombinations, accompanied by the erosion of the accuracy of prediction. While accurately quantifying the erosion at the individual SNP level is a difficult and unresolved task, quantifying the erosion of the accuracy of prediction is a more tractable problem. In this paper, we describe a method that uses the relationship between reference and target populations to calculate expected values for the accuracies of predicted breeding values for non-phenotyped individuals accounting for erosion. The accuracy of the expected values was evaluated through simulations, and a further evaluation was performed on real data. RESULTS: Using simulations, we empirically confirmed that our expected values for the accuracy of PBV accounting for erosion were able to correctly determine the prediction accuracy of breeding values for non-phenotyped individuals. When comparing the expected to the realized accuracies of PBV with real data, only one out of the four traits evaluated presented accuracies that were significantly higher than the expected, approaching h 2 . CONCLUSIONS: We defined an index of genetic correlation between reference and target populations, which summarizes the expected overall erosion due to differences in allele frequencies and LD patterns between populations. We used this correlation along with a trait's heritability to derive expected values for the accuracy ( R ) of PBV accounting for the erosion, and demonstrated that our derived E R | erosion is a reliable metric.


Assuntos
Modelos Genéticos , Locos de Características Quantitativas , Humanos , Animais , Genótipo , Fenótipo , Cruzamento , Polimorfismo de Nucleotídeo Único , Seleção Genética
13.
J Evol Biol ; 37(3): 353-359, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38309717

RESUMO

According to Michener's paradox, most altruistic groups in nature should be small and large groups should not exist. This is because per capita productivity is thought to decrease as groups get larger, meaning that the share of indirect fitness available to each group member declines, which favours dispersal. The empirical evidence for a decrease in per capita productivity is contradictory, however, and limited to the social Hymenoptera. I report that per capita reproductive success decreased with increasing group size across 26 cooperatively breeding bird species. Small groups comprising two or three individuals were the most common (79% of 16,101 groups), and these had the highest per capita reproductive success. This close fit between per capita reproductive success and the distribution of group sizes in nature suggests that it may indeed be difficult for large groups to evolve through indirect fitness benefits alone.


Assuntos
Altruísmo , Aves , Humanos , Animais , Cruzamento , Cabeça , Reprodução
14.
Science ; 383(6685): 803-804, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38386729

RESUMO

Breeder would be the country's largest; locals and animal welfare advocates are concerned.


Assuntos
Experimentação Animal , Bem-Estar do Animal , Cruzamento , Animais , Experimentação Animal/ética , Haplorrinos , Estados Unidos , Pesquisa Farmacêutica
15.
Anim Sci J ; 95(1): e13915, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38303133

RESUMO

The aim of this study was to investigate the muscle fiber types and meat quality in four populations and estimate the heritability and correlation coefficients of those traits in Shanxia long black pig (SX). In this study, a total of 318 pigs were recorded for 16 traits of the muscle fiber types and meat quality in four populations, including 256 individuals from the new breed SX. The population had a significant effect on all recorded traits, and the meat quality of the Lulai black pig was better than the remaining populations. The heritability (h2 ) of meat quality traits was from 0.06 (pH at 24 h) to 0.47 (shearing force), and the muscle fiber types belonged to the traits with low to medium heritability. The density of total fiber had the highest h2 (0.40), while the percentage of type IIA had the lowest h2 (0.04). Most traits are phenotypically correlated with each other, but only a small proportion of traits are genetically correlated with each other. None fiber type genetically correlated with meat quality significantly, because the genetic correlation coefficients had large standard errors. These results provided some insights into genetic improvements for the meat quality in pig breeds and also indicated that the parameters of muscle fiber characteristics can explain parts of the variation in meat quality.


Assuntos
Carne , Fibras Musculares Esqueléticas , Humanos , Suínos/genética , Animais , Fibras Musculares Esqueléticas/fisiologia , Fenótipo , Carne/análise , Cruzamento
16.
Mol Ecol ; 33(6): e17298, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38361438

RESUMO

Inbreeding depression, that is, the reduction of health and vigour in individuals with high inbreeding coefficients, is expected to increase with environmental, social, or physiological stress. It has therefore been predicted that sexual selection and the associated stress usually lead to higher inbreeding depression in males than in females. However, sex-specific differences in life history may reverse that pattern during certain developmental stages. In some salmonids, for example, female juveniles start developing their gonads earlier than males who instead grow faster. We tested whether the sexes are differently affected by inbreeding during that time. To study the effects of inbreeding coefficients that may be typical for natural populations of brown trout (Salmo trutta), and also to control for potentially confounding maternal or paternal effects, we sampled males and females from the wild, used their gametes in a block-wise full-factorial breeding design to produce 60 full-sib families, released the offspring as yolk-sac larvae into the wild, sampled them 6 months later, identified their genetic sex, and used microsatellites to assign them to their parents. We used whole-genome resequencing to calculate the kinship coefficients for each breeding pair and hence the expected average inbreeding coefficient per family. Juvenile growth could be predicted from these expected inbreeding coefficients and the genetic sex: Females reached lower body sizes with increasing inbreeding coefficient, while no such link could be found in males. This sex-specific inbreeding depression led to the overall pattern that females were on average smaller than males by the end of their first summer.


Assuntos
Genoma , Endogamia , Humanos , Masculino , Animais , Feminino , Cruzamento , Truta/genética
17.
Braz J Biol ; 84: e278879, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422294

RESUMO

Fine-fleeced sheep are distinguished by numerous economically valuable traits that constitute the foundation for productive distinctions among breeds, populations, lines, and individuals. Many of these traits have already been mentioned or thoroughly examined during studies on the correlative variability of productivity indicators, blood parameters, characteristics of pulmonary gas exchange, histological structures of the skin, and features of the experimental sheep's coat. The objective of our research was to investigate the correlative variability of key economically valuable traits that characterize the overall functional state of sheep organisms under varying environmental conditions. The study was conducted at the "Sharbulak" breeding farms and the "Samat" peasant farms in the Kazygurt district of the Turkestan region. Our findings reveal that one-year-old rams surpass ewes in terms of live weight by 32-37% and in terms of unwashed wool shearing by 21-23%. Two-year-old rams outperform ewes in live weight by 2.15-2.17 times and in unwashed wool shearing by 2.38-2.44 times. The highest phenotypic variability in relative terms (as indicated by the coefficient of variation) is observed in the shearing of pure wool, with an average coefficient of variation of 18.1% across all sex and age groups of sheep. This is followed by the wool coefficient (17.4%) and the yield of pure fiber (12.5%). For each group of animals, the most substantial phenotypic correlation coefficients were observed between the live weight of sheep and the shearing of unwashed wool. On average, across all groups of sheep at the "Sharbulak" breeding farm, this phenotypic correlation reaches +0.411 ± 0.077. Correspondingly, for the sheep herd at the "Samat" peasant farm, it is +0.326 ± 0.075. The second-highest phenotypic correlation pertains to the cut of unwashed wool and the length of wool (with correlation coefficients of +0.156 ± 0.058 and +0.145 ± 0.057, respectively, for the herds). The third-highest correlation involves live weight and wool length (+0.131 ± 0.085 and +0.105 ± 0.078, respectively). No statistically significant differences were identified in the average correlation coefficients between the live weight of sheep, the shearing of unwashed wool, and the length of the staple among the flocks of sheep at the "Sharbulak" breeding farm and the "Samat" peasant farm.


Assuntos
Cruzamento , Carneiro Doméstico , Humanos , Ovinos , Animais , Feminino , Masculino , Lactente , Pré-Escolar , Fazendas , Fenótipo , Pesquisa
18.
Malar J ; 23(1): 60, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38413961

RESUMO

BACKGROUND: When integrated with insecticide-treated bed nets, larval control of Anopheles mosquitoes could fast-track reductions in the incidence of human malaria. However, larval control interventions may deliver suboptimal outcomes where the preferred breeding places of mosquito vectors are not well known. This study investigated the breeding habitat choices of Anopheles mosquitoes in southern Nigeria. The objective was to identify priority sites for mosquito larval management in selected urban and periurban locations where malaria remains a public health burden.  METHODS: Mosquito larvae were collected in urban and periurban water bodies during the wet-dry season interface in Edo, Delta, and Anambra States. Field-collected larvae were identified based on PCR gel-electrophoresis and amplicon sequencing, while the associations between Anopheles larvae and the properties and locations of water bodies were assessed using a range of statistical methods. RESULTS: Mosquito breeding sites were either man-made (72.09%) or natural (27.91%) and mostly drainages (48.84%) and puddles (25.58%). Anopheles larvae occurred in drainages, puddles, stream margins, and a concrete well, and were absent in drums, buckets, car tires, and a water-holding iron pan, all of which contained culicine larvae. Wild-caught Anopheles larvae comprised Anopheles coluzzii (80.51%), Anopheles gambiae sensu stricto (s.s.) (11.54%), and Anopheles arabiensis (7.95%); a species-specific PCR confirmed the absence of the invasive urban malaria vector Anopheles stephensi among field-collected larvae. Anopheles arabiensis, An. coluzzii, and An. gambiae s.s. displayed preferences for turbid, lowland, and partially sunlit water bodies, respectively. Furthermore, An. arabiensis preferred breeding sites located outside 500 m of households, whereas An. gambiae s.s. and An. coluzzii had increased detection odds in sites within 500 m of households. Anopheles gambiae s.s. and An. coluzzii were also more likely to be present in natural water bodies; meanwhile, 96.77% of An. arabiensis were in man-made water bodies. Intraspecific genetic variations were little in the dominant vector An. coluzzii, while breeding habitat choices of populations made no statistically significant contributions to these variations. CONCLUSION: Sibling malaria vectors in the An. gambiae complex display divergent preferences for aquatic breeding habitats in southern Nigeria. The findings are relevant for planning targeted larval control of An. coluzzii whose increasing evolutionary adaptations to urban ecologies are driving the proliferation of the mosquito, and An. arabiensis whose adults typically evade the effects of treated bed nets due to exophilic tendencies.


Assuntos
Anopheles , Malária , Animais , Adulto , Humanos , Anopheles/genética , Mosquitos Vetores , Nigéria , Malária/epidemiologia , Água , Larva , Cruzamento
19.
Sci Rep ; 14(1): 4075, 2024 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374332

RESUMO

Conditions experienced by an individual during migration have the potential to shape migratory tactic and in turn fitness. For large birds, environmental conditions encountered during migration have been linked with survival and subsequent reproductive output, but this is less known for smaller birds, hindering our understanding of mechanisms driving population change. By combining breeding and tracking data from 62 pied flycatchers (Ficedula hypoleuca) representing two breeding populations collected over 2016-2020, we determine how variation in migration phenology and tactic among individuals affects subsequent breeding. Departure date from West African non-breeding areas to European breeding grounds was highly variable among individuals and had a strong influence on migration tactic. Early departing individuals had longer spring migrations which included longer staging duration yet arrived at breeding sites and initiated breeding earlier than later departing individuals. Individuals with longer duration spring migrations and early arrival at breeding sites had larger clutches, and for males higher fledging success. We suggest that for pied flycatchers, individual carry-over effects may act through departure phenology from West Africa, and the associated spring migration duration, to influence reproduction. While our results confirm that departure date from non-breeding areas can be associated with breeding success in migratory passerines, we identify spring staging duration as a key component of this process.


Assuntos
Migração Animal , Aves Canoras , Humanos , Masculino , Animais , Estações do Ano , Cruzamento , Reprodução
20.
J Insect Sci ; 24(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38366859

RESUMO

A study was conducted to investigate the population genetic structure and breeding pattern of 140 tropical bed bugs, Cimex hemipterus (F.) (Hemiptera: Cimicidae), collected from 14 infested sites in major cities in Iraq. The samples were genotyped using a set of 7 polymorphic microsatellite markers. High genetic variety was seen among populations, with an average of 2-9 alleles per locus. The number of alleles across 7 microsatellite loci was between 6 and 18. There was a notable disparity in the alleles per loci when comparing the overall population to those within it. The overall population exhibited an average observed heterozygosity of 0.175 and an average expected heterozygosity of 0.730. Among the population, the average observed heterozygosity was 0.173, while the average expected heterozygosity was 0.673. Analysis of molecular variance (AMOVA) revealed that 93% of the genetic variability was within the populations, and 7% was among them. The genetic differentiation coefficient (FST = 0.045), indicates a low degree of genetic differentiation and a high degree of inbreeding (FIS = 0.761), as indicated by notably significant positive inbreeding coefficients. Admixed individuals were revealed using STRUCTURE and neighbor-joining phylogenetic trees, demonstrating moderate gene flow between populations and a lack of genetic structure in the regional groups. Thus, both active dispersion and human-mediated dispersion possess the potential to influence the low population genetic structure of tropical bed bug C. hemipterus populations in Iraq, which can have implications toward tropical bed bug and management strategies.


Assuntos
Percevejos-de-Cama , Humanos , Animais , Percevejos-de-Cama/genética , Filogenia , Iraque , Cruzamento , Genética Populacional
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