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1.
BMC Genomics ; 25(1): 614, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890559

RESUMO

BACKGROUND: To unravel the evolutionary history of a complex group, a comprehensive reconstruction of its phylogenetic relationships is crucial. This requires meticulous taxon sampling and careful consideration of multiple characters to ensure a complete and accurate reconstruction. The phylogenetic position of the Orestias genus has been estimated partly on unavailable or incomplete information. As a consequence, it was assigned to the family Cyprindontidae, relating this Andean fish to other geographically distant genera distributed in the Mediterranean, Middle East and North and Central America. In this study, using complete genome sequencing, we aim to clarify the phylogenetic position of Orestias within the Cyprinodontiformes order. RESULTS: We sequenced the genome of three Orestias species from the Andean Altiplano. Our analysis revealed that the small genome size in this genus (~ 0.7 Gb) was caused by a contraction in transposable element (TE) content, particularly in DNA elements and short interspersed nuclear elements (SINEs). Using predicted gene sequences, we generated a phylogenetic tree of Cyprinodontiformes using 902 orthologs extracted from all 32 available genomes as well as three outgroup species. We complemented this analysis with a phylogenetic reconstruction and time calibration considering 12 molecular markers (eight nuclear and four mitochondrial genes) and a stratified taxon sampling to consider 198 species of nearly all families and genera of this order. Overall, our results show that phylogenetic closeness is directly related to geographical distance. Importantly, we found that Orestias is not part of the Cyprinodontidae family, and that it is more closely related to the South American fish fauna, being the Fluviphylacidae the closest sister group. CONCLUSIONS: The evolutionary history of the Orestias genus is linked to the South American ichthyofauna and it should no longer be considered a member of the Cyprinodontidae family. Instead, we submit that Orestias belongs to the Orestiidae family, as suggested by Freyhof et al. (2017), and that it is the sister group of the Fluviphylacidae family, distributed in the Amazonian and Orinoco basins. These two groups likely diverged during the Late Eocene concomitant with hydrogeological changes in the South American landscape.


Assuntos
Ciprinodontiformes , Evolução Molecular , Genoma , Filogenia , Animais , Ciprinodontiformes/genética , Ciprinodontiformes/classificação , Elementos de DNA Transponíveis/genética , Tamanho do Genoma
2.
Genomics ; 114(1): 305-315, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34954349

RESUMO

Orestias ascotanensis (Cyprinodontidae) is a teleost pupfish endemic to springs feeding into the Ascotan saltpan in the Chilean Altiplano (3,700 m.a.s.l.) and represents an opportunity to study adaptations to high-altitude aquatic environments. We have de novo assembled the genome of O. ascotanensis at high coverage. Comparative analysis of the O. ascotanensis genome showed an overall process of contraction, including loss of genes related to G-protein signaling, chemotaxis and signal transduction, while there was expansion of gene families associated with microtubule-based movement and protein ubiquitination. We identified 818 genes under positive selection, many of which are involved in DNA repair. Additionally, we identified novel and conserved microRNAs expressed in O. ascotanensis and its closely-related species, Orestias gloriae. Our analysis suggests that positive selection and expansion of genes that preserve genome stability are a potential adaptive mechanism to cope with the increased solar UV radiation to which high-altitude animals are exposed to.


Assuntos
Fundulidae , Peixes Listrados , Adaptação Fisiológica/genética , Altitude , Animais , Fundulidae/genética , Peixes Listrados/genética , Filogenia , Transcriptoma
3.
Parasitol Res ; 121(5): 1295-1304, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35230547

RESUMO

Zoonotic larvae of the family Anisakidae found in several fish species represent a serious risk in public health since they may cause food-borne anisakidosis in humans. Chile has culinary preferences including eating raw fish in many traditional preparations. In the present study, a total of 180 fish specimens representing three different fish species, i.e., Chilean hake (Merluccius gayi), snoek (Thyrsites atun), and sea bream (Brama australis), were caught at central coast of Chile. Parasitological examination was performed on musculature and abdominal cavity for subsequent extraction and quantification of anisakid larvae. Estimation of infection parameters, such as prevalence, was performed indicating 100% (CI: 0.94-1.0) prevalence of anisakid L3 in Chilean hakes and snoeks. Moreover, sea breams reached a prevalence of 35% (CI: 0.23-0.48). Prevalence of anisakid larvae in muscle was also analyzed showing values of 18.6% (CI: 0.097-0.309) in Chilean hakes, 15% (CI: 0.07-0.26) in snoeks, and 1.7% (CI: 0-0.089) in sea breams. Meanwhile, prevalence of anisakid larvae in internal organs showed highest values for peritoneum (100% and 83.3%) for snoeks and Chilean hakes, respectively, for liver (96.7%) and gonads (86.6%) in Chilean hakes, and for intestine (98.3%) in snoeks. Molecular analysis of collected anisakid L3 unveiled presence of two potentially zoonotic nematode species, i.e., Pseudoterranova cattani and Anisakis pegreffii. P. cattani was found in Chilean hakes and snoeks being the first molecular host species report for Chilean snoeks. Besides, A. pegreffii was also identified in these species being the first molecular report on this regard. These findings are relevant for better understanding of epidemiology of anisakiasis in Chilean coasts and for public health issues considering potential risk of human population due to its culinary preferences in eating raw fish.


Assuntos
Anisaquíase , Anisakis , Ascaridoidea , Doenças dos Peixes , Gadiformes , Perciformes , Animais , Anisaquíase/epidemiologia , Anisaquíase/veterinária , Anisakis/genética , Ascaridoidea/genética , Chile/epidemiologia , Doenças dos Peixes/epidemiologia , Peixes , Humanos , Larva/genética , Prevalência
4.
Rev Chil Pediatr ; 89(4): 448-453, 2018 Aug.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-30571817

RESUMO

BACKGROUND: Food allergy (FA) is an entity of high and growing prevalence, which can be mediated by IgE or cellular immunity. It can have a wide range of symptoms and be triggered by multiple food antigens, which vary in different geographical areas. OBJECTIVES: To describe clinical characteristics of Chilean patients with IgE-mediated FA. PATIENTS AND METHOD: Retrospective review of patients with IgE-mediated FA treated at a tertiary healthcare center in Santiago, Chile, between 2006 and 2016. Demographic characteristics, clinical manifestations, and trigger foods were evaluated. RESULTS: A to tal of 282 patients diagnosed with IgE-mediated FA were included. 89% had FA onset before 18 years of age and most of these before one year of age (median of age: one year; range: one month-55 years). The most common clinical manifestations were hives, angioedema, dyspnea, and vomiting. 40% had symptoms compatible with anaphylaxis. The foods most frequently involved were egg, cow's milk, peanut, shellfish, walnut, tomato, wheat, avocado, fish, and legumes. Egg, cow's milk, and peanut allergies were the most frequent at pediatric age, while seafood allergy was the most frequent among adults. CONCLUSION: Foods causing IgE-mediated FA in Chile were similar to those described in other countries, although the frequency of tomato and avocado allergy, which are unusual in international series, stands out. Anaphylaxis incidence was high, emphasizing the need for epinephrine autoinjec tors in Chile.


Assuntos
Hipersensibilidade Alimentar/diagnóstico , Imunoglobulina E/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Chile/epidemiologia , Feminino , Hipersensibilidade Alimentar/epidemiologia , Hipersensibilidade Alimentar/imunologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Ann Neurol ; 75(3): 411-28, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24700511

RESUMO

OBJECTIVE: To report the clinical, radiological, and immunological association of demyelinating disorders with anti­Nmethyl- D-aspartate receptor (NMDAR) encephalitis. METHODS: Clinical and radiological analysis was done of a cohort of 691 patients with anti-NMDAR encephalitis. Determination of antibodies to NMDAR, aquaporin-4 (AQP4), and myelin oligodendrocyte glycoprotein (MOG) was performed using brain immunohistochemistry and cell-based assays. RESULTS: Twenty-three of 691 patients with anti-NMDAR encephalitis had prominent magnetic resonance imaging (MRI) and/or clinical features of demyelination. Group 1 included 12 patients in whom anti-NMDAR encephalitis was preceded or followed by independent episodes of neuromyelitis optica (NMO) spectrum disorder (5 cases, 4 anti-AQP4 positive) or brainstem or multifocal demyelinating syndromes (7 cases, all anti-MOG positive). Group 2 included 11 patients in whom anti-NMDAR encephalitis occurred simultaneously with MRI and symptoms compatible with demyelination (5 AQ4 positive, 2 MOG positive). Group 3 (136 controls) included 50 randomly selected patients with typical anti-NMDAR encephalitis, 56 with NMO, and 30 with multiple sclerosis; NMDAR antibodies were detected only in the 50 anti-NMDAR patients, MOG antibodies in 3 of 50 anti-NMDAR and 1 of 56 NMO patients, and AQP4 antibodies in 48 of 56 NMO and 1 of 50 anti-NMDAR patients (p<0.0001 for all comparisons with Groups 1 and 2). Most patients improved with immunotherapy, but compared with anti-NMDAR encephalitis the demyelinating episodes required more intensive therapy and resulted in more residual deficits. Only 1 of 23 NMDAR patients with signs of demyelination had ovarian teratoma compared with 18 of 50 anti-NMDAR controls (p50.011). INTERPRETATION: Patients with anti-NMDAR encephalitis may develop concurrent or separate episodes of demyelinating disorders, and conversely patients with NMO or demyelinating disorders with atypical symptoms (eg, dyskinesias, psychosis) may have anti-NMDAR encephalitis.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Doenças Desmielinizantes/complicações , Adolescente , Adulto , Animais , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Encefalite Antirreceptor de N-Metil-D-Aspartato/imunologia , Encefalite Antirreceptor de N-Metil-D-Aspartato/patologia , Aquaporina 4/imunologia , Autoanticorpos/imunologia , Encéfalo/imunologia , Encéfalo/patologia , Criança , Pré-Escolar , Doenças Desmielinizantes/diagnóstico , Doenças Desmielinizantes/imunologia , Doenças Desmielinizantes/patologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Glicoproteína Mielina-Oligodendrócito/imunologia , Neuroimagem , Ratos , Receptores de N-Metil-D-Aspartato/imunologia
7.
Pediatr Allergy Immunol ; 25(4): 338-43, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24628618

RESUMO

BACKGROUND: Recent studies suggest an association between higher latitude, a proxy of vitamin D (VD) status, and allergic diseases. Chile provides an ideal setting to study this association due to its latitude span and high rates of VD deficiency in southern regions. The aim of this study is to explore the associations of latitude and solar radiation with anaphylaxis admission rates. METHODS: We reviewed anaphylaxis admissions in Chile's hospital discharge database between 2001 and 2010 and investigated associations with latitude and solar radiation. RESULTS: 2316 anaphylaxis admissions were registered. Median age of patients was 41 yr; 53% were female. National anaphylaxis admission rate was 1.41 per 100,000 persons per year. We observed a strong north-south increasing gradient of anaphylaxis admissions (ß 0.04, p = 0.01), with increasing rates south of latitude 34°S. A significant association was also observed between solar radiation and anaphylaxis admissions (ß -0.11, p = 0.009). Latitude was associated with food-induced (ß 0.05, p = 0.02), but not drug-induced (ß -0.002, p = 0.27), anaphylaxis. The association between latitude and food-induced anaphylaxis was significant in children (ß 0.01, p = 0.006), but not adults (ß 0.003, p = 0.16). Anaphylaxis admissions were not associated with regional sociodemographic factors like poverty, rurality, educational level, ethnicity, or physician density. CONCLUSIONS: Anaphylaxis admission rates in Chile are highest at higher latitudes and lower solar radiation, used as proxies of VD status. The associations appear driven by food-induced anaphylaxis. Our data support a possible role of VD deficiency as an etiological factor in the high anaphylaxis admission rates found in southern Chile.


Assuntos
Anafilaxia/epidemiologia , Admissão do Paciente/estatística & dados numéricos , Energia Solar , Vitamina D/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Chile/epidemiologia , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
P R Health Sci J ; 43(1): 25-31, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38512758

RESUMO

OBJECTIVE: Neonatal abstinence syndrome (NAS) is a set of drug withdrawal symptoms suffered by neonates exposed to drugs in utero. Several studies have widely described NAS incidence and treatment approach; however, little is known regarding the incidence and manifestations of this disease in Puerto Rico (PR). The principal aim of this study was to describe NAS incidence in the neonatal units of hospitals affiliated with the University of PR in terms of occurrence, clinical manifestations, and treatment approaches. METHODS: Our study evaluated the medical records of NAS babies diagnosed from 2018 through 2020 at 2 hospitals affiliated with the University of PR Medical Sciences Campus. Descriptive and inferential statistics were employed to analyze trends. RESULTS: We identified 12 neonates diagnosed with NAS, 5 with low birthweights (<2500 g); for a NAS incidence of 2 cases per 1000 admitted for the 3 years of recollected data. The urine toxicology results revealed that 9 had experienced intrauterine polydrug exposure. Phenobarbital loading dose were determined on the day of diagnosis (indicated by Finnegan score). The first manifestation of NAS symptoms varied: 8 neonates showed symptoms within 48 hours after birth, whereas 4 had withdrawal symptoms within 72-120 hours of their births. Differences between dosing practices and guidelines were observed, ranging from a 0.69% to a 25% difference during treatment initiation. CONCLUSION: Further research on the incidence of NAS in PR (national level) is needed for a deeper understanding that we hope will lead to the development of enhanced treatment protocols in PR.


Assuntos
Metadona , Síndrome de Abstinência Neonatal , Recém-Nascido , Humanos , Metadona/uso terapêutico , Síndrome de Abstinência Neonatal/tratamento farmacológico , Síndrome de Abstinência Neonatal/epidemiologia , Síndrome de Abstinência Neonatal/diagnóstico , Porto Rico/epidemiologia , Unidades de Terapia Intensiva Neonatal , Universidades , Analgésicos Opioides/uso terapêutico
10.
Landsc Urban Plan ; 120: 16-24, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25550677

RESUMO

Restoration of belowground ecology is seldom a priority in designing revegetation strategies for disturbed landscapes. We determined earthworm abundance and diversity in a 16-year old grass sward (grassland), a 6-year old (Plantation-04) and a 4-year old (Plantation-06) plantation, both of mixed woody species, on a reclaimed waste disposal site, and in nearby remnant woodland, in suburban Sydney, Australia. While no catches were made in autumn, more earthworms were found in spring (21 ± 8.6 m-2) than in winter (10.2 ± 5.9 m-2) or summer (14.4 ± 5.5 m-2). Earthworm abundance in spring was in the order grassland ≈ Plantation-04 (35.2 m-2) > woodland (12.8 m-2) > Plantation-06 (0.8 m-2). None of the revegetated covers had restored earthworm diversity to levels found in the woodland. Exotic species, mostly Microscolex dubius, dominated in the four vegetation covers at any time; the only two native species (Heteroporodrilus sp. and Megascoleceides sp.) found were in the woodland. We also assessed how quality of the evolving soils from the three revegetated covers, compared with that from the woodland, impacted viability of common exotic earthworm species. Both weight gain and cocoon production by the exotic earthworms were higher in the soil from Plantation-04 than in soils from the other vegetation covers, including the woodland; the two variables were positively correlated with the pH and mineral nutrient content (as indicated by electrical conductivity that was in turn correlated with clay content) of the soil. Age of vegetation rather than its composition explained differences in the level of earthworm recovery observed.

11.
Open Vet J ; 12(1): 99-104, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342729

RESUMO

Background: External otitis is common in dogs, and one of the main agents involved is Malassezia pachydermatis, a yeast belonging to the otic microbiota. Empirical treatment can fail; therefore, it is essential to know the antifungal susceptibility profile to prescribe appropriate treatment, a fact scarcely reported in Chile. Aim: This study aimed to determine the antifungal sensitivity of M. pachydermatis isolated from the external auditory canal of dogs in central Chile. Methods: Ear swabs from 30 dogs (15 healthy and 15 with external otitis) were used. Samples were subjected to cytology and fungal culture. The antifungal susceptibility was determined according to clinical and laboratory standards institute (CLSI) document M44A-2 using the disk diffusion test from amphotericin B, Caspofungin, fluconazole, nystatin, clotrimazole, and voriconazole were used. Results: The prevalence of M. pachydermatis was 66.7% from 8 healthy dogs and 12 with otitis. While fungal culture was not associated with the patient's clinical condition (p = 0.24), the yeast count by cytology was significantly higher in dogs with otitis (p = 0.003). The strains were sensitive to all antifungals except for Caspofungin, where 55% of the strains were resistant. Conclusion: Malassezia pachydermatis is isolated more frequently in dogs with otitis, and the ear cytological examination is useful to differentiate colonized dogs versus dogs with otitis. In addition, most antifungals in vitro are active against this yeast, except Caspofungin, an antifungal used in human medicine. This situation should be further monitored in epidemiological programs to evaluate the possible impact on Chilean public health.


Assuntos
Dermatomicoses , Doenças do Cão , Malassezia , Otite Externa , Animais , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Caspofungina/uso terapêutico , Chile/epidemiologia , Dermatomicoses/tratamento farmacológico , Dermatomicoses/epidemiologia , Dermatomicoses/veterinária , Doenças do Cão/tratamento farmacológico , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Cães , Otite Externa/tratamento farmacológico , Otite Externa/epidemiologia , Otite Externa/veterinária , Saccharomyces cerevisiae
13.
Arch Latinoam Nutr ; 61(2): 149-53, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22308941

RESUMO

Obesity is associated with a low grade inflammation which contributes to the development of insulin resistance and diabetes. The aim of this study was to assess the total saturated (SFAs), monounsaturated (MUFAs) and polyunsaturated fatty acids (PUFAs) in plasma from asymptomatic obese subjects and to determine the arachidonic/eicosapentanoic acid ratio [ARA/EPA] as a marker of inflammation, and its eventual association with ultrasensitive CRP. Fourteen obese (34.4 +/- 11.1y.; BMI: 36.0 +/- 4,5 kg/m2) and 12 normal-weight (30.6 +/- 7.8y.; BMI: 23,6 +/- 2,4 kg/m2) subjects were recruited and their plasma fatty acids were determined by gas chromatography. usCRP was higher in the obese subjects (p = 0.01) and correlates with their body fat content. The percentages of SFAs, MUFAs, PUFAs were not affected in the obese subjects but their concentrations were increased, compared with the control group. However, no differences in the long chain PUFAs (DHA and EPA) concentrations or in the plasmatic ARA/EPA ratio were observed in these subjects. These observations do not support a relation between the ARA/EPA ratio and the presence of low grade inflammation evaluated by plasma usCRP in this group of asymptomatic obese subjects.


Assuntos
Ácidos Graxos Monoinsaturados/sangue , Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Ácidos Graxos Insaturados/sangue , Obesidade/sangue , Adolescente , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Estudos de Casos e Controles , Ácidos Docosa-Hexaenoicos/sangue , Ácido Eicosapentaenoico/sangue , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
J Rheumatol ; 48(11): 1725-1731, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33934075

RESUMO

OBJECTIVE: To evaluate the clinical and demographic characteristics of patients with juvenile idiopathic arthritis (JIA) in Chile and compare treatments and outcomes before and after the introduction in 2010 of the Explicit Health Guarantees (GES) for JIA, a national universal access program for diagnosis and treatment of this condition. METHODS: The clinical records of 280 patients with JIA followed at a private tertiary academic health network between 2007 and 2018 were reviewed. RESULTS: Seventy percent of patients with JIA were female, mean age at diagnosis was 8.5 ± 4.8 years and mean follow-up was 4.0 ± 3.7 years. After GES implementation (post-GES), time to evaluation by pediatric rheumatologist and diagnostic delay were significantly reduced (15.0 ± 4.5 vs 9.0 ± 4.2 months, P = 0.004). In addition, use of magnetic resonance imaging significantly increased post-GES (P < 0.001). In terms of JIA treatments, before GES implementation, no patients received biologics. Of the 67 patients diagnosed before 2010 with continued follow-up at our center, 34% began biologic treatment after GES implementation. Of 196 patients diagnosed post-GES, 46% were treated with biologics. JIA remission rates were significantly higher in patients diagnosed post-GES compared to pre-GES (43% vs 29%, P = 0.02). Post-GES, we observed a significant decrease in uveitis complications among JIA patients (45% vs 13%, P = 0.04). CONCLUSION: The implementation of a national government-mandated universal access program for guaranteed JIA diagnosis and treatment led to earlier access to a pediatric rheumatologist and JIA diagnosis, increased rates of treatment with biologic drugs, higher rates of clinical remission, and lower rates of uveitis complications in Chilean children with JIA.


Assuntos
Artrite Juvenil , Uveíte , Artrite Juvenil/diagnóstico , Artrite Juvenil/tratamento farmacológico , Criança , Chile , Diagnóstico Tardio , Feminino , Humanos
16.
Arch Latinoam Nutr ; 60(2): 199-204, 2010 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-21427888

RESUMO

An optimized formulation of pate was developed using rainbow trout discard with the employment ofTaguchi methodology, taking into account that the health-promoting benefits of this resource makes it a viable alternative as a functional foods to help consumers to get a healthy lifestyle. The optimization process utilizing Taguchi methodology was carried out in two phases. First, an orthogonal array L(8)2(7) with seven independent variables was chosen to select the control factors with a significant effect on the sensory quality (SQ). As a result, the following independent variables were selected: merkén pepper, sodium chloride, vegetal lard and margarine. In the second stage the L(9)3(4) orthogonal array was used. Data were analysed using differences between average values of factors according working levels, and also ANOVA, summing up that merken pepper, sodium chloride and margarine showed a significant effect (p > 0.05) on the SQ. Best combination turned to be: merkén 0.7%, sodium chloride 1.3%, vegetal lard 5.2% and margarine 5.2%. Among the chemical characteristics highlighted protein 13.8%, lipid 10.21%, caloric density 175 Kcal/100 g and cholesterol 46 mg/100 g. Shelf life study during a period of time of 6 weeks at 5 degrees C expressed as mesophyl aerobic count (MAC) and peroxide index were 1.6E+0.4 ufc/g and 8.44 meg O2/Kg respectively, both characteristics lower than the maximum limits allowed for chilean regulations. Concerning to the acceptability of the optimized product the hedonic test showed 91% approval and also 87% of consumers would be well disposed to buy this product.


Assuntos
Produtos Pesqueiros , Manipulação de Alimentos/métodos , Conservação de Alimentos , Oncorhynchus mykiss , Paladar , Animais , Valor Nutritivo
17.
J Equine Vet Sci ; 92: 103170, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32797792

RESUMO

In this work, we investigated the influence of age and seasonality on sperm motility and DNA fragmentation in post-thawing semen from Chilean Purebred Stallions (CPS), a horse breed presenting the oldest genealogy record in South America with an interesting reproductive industry. Despite that semen from aged CPS is frozen all year round, there is a lack of studies characterizing the breed semen freezability in accordance with age and seasonality. Twenty fertile CPS were grouped into the young group, the middle group, and the aged group. Ten ejaculates from each stallion were obtained by using an artificial vagina during summer (December) and winter (July) and directly frozen. Subsequently, the frozen semen was thawed and analyzed by a computer-assisted semen analysis and flow cytometer assessing progressive motility, mean velocity, and DNA fragmentation spermatozoa. Kruskal-Wallis test and Pearson's correlation were used to determine statistical differences among groups and correlation among variables (P ≤ .05). Both spermatozoa motility traits decreased progressively in accordance with age and seasonality, showing the lowest values in the aged group during winter and the highest values in the young group during summer. Deoxyribonucleic acid fragmentation increased significantly in accordance with age and seasonality being highest in the aged group during winter and lowest in the young group during summer. Post-thawing sperm quality showed a negative correlation with the age of the stallions and a positive correlation with the normal sperm morphology before freezing. These results allow the conclusion that age and seasonality are important factors that need to be considered during the selection of CPS for reproductive programs.


Assuntos
Preservação do Sêmen , Motilidade dos Espermatozoides , Animais , Chile , Criopreservação/veterinária , Feminino , Cavalos , Masculino , Preservação do Sêmen/veterinária , Espermatozoides
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