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Scrotal surface thermography is a non-invasive method for assessing testicular thermoregulation in stallions; however, few studies have explored the application of this technique concerning the thermal physiology of equine reproductive systems. This study aimed to evaluate the consistency of testicular thermoregulation in stallions over a year using thermography to measure the scrotal surface temperature (SST). Moreover, we assessed the best region for measuring the surface body temperature compared with the SST. Ten light-breed stallions were used in the experiment. Thermographic images of the scrotal and body surfaces (neck and abdomen) were captured. Fresh, cooled and frozen-thawed semen samples were evaluated to verify the impact of thermoregulation on semen quality. Testicular thermoregulation was maintained throughout the year in stallions amidst changes in the external temperature, as evidenced by the weak correlation between the SST and ambient temperature. A lower correlation was observed between the environmental temperature and body surface temperature (BTS) obtained from the abdomen (BTS-A; R = .4772; p < .0001) than with that obtained from the neck (BTS-N; R = .7259; p < .0001). Moreover, both BTS-A and SST were simultaneously captured in a single image. The consistent quality of the fresh, cooled and frozen semen suggests efficient thermoregulation in stallions throughout the year.

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This study describes the implications of cardiac ventricular microscopy in Chelonia mydas relating to its ability to dive. For this work, 11 specimens of the marine turtle species C. mydas found dead on the coast of Rio Grande do Norte (Northeast Brazil) were used. After necropsy, fragments of the cardiac ventricular wall were fixed in 10% buffered formaldehyde solution for 24 h and then subjected to routine processing for light and scanning electron microscopy (SEM). The ventricle in this species is formed by the epicardium, myocardium and endocardium. The subepicardial layer consists of highly vascularised connective tissue that emits septa to reinforce the myocardium surface. There is an abundant and diffuse subepicardial nerve plexus shown by immunostaining technique. The thickness of the spongy myocardium and the nature of its trabeculae varied between the heart chambers. The endocardium shows no characteristic elements of the heart conduction system. The valves have a hyaline cartilage skeleton, coated by dense irregular connective tissues characterised by elastic fibres. These findings in the green turtle ventricular microscopy are related to hypoxia resistance during diving.

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Genomic imprinting is an important epigenetic phenomenon, wherein genes or gene clusters are marked by DNA methylation during gametogenesis. This plays a major role in several functions of normal cells, including cell differentiation, X chromosome inactivation, and the maintenance of chromatin structure, in mammalian development. The aim of this study was to investigate the possible differences in SNRPN gene methylation profiles in non-obese and obese individuals, and in children and adults. Our results did not reveal any statistical correlations between the DNA methylation profiles of the SNRPN gene in children or adult obese and non-obese groups. However, a comparison of the methylation levels with the chronological age revealed statistically significant differences between the means of methylation in adults and children (46.20 ± 5.88 and 39.40 ± 2.87, respectively; P < 0.001). Pearson's correlation analysis indicated a positive association between the level of DNA methylation and the chronological age (R2 = 0.326; P < 0.001). Therefore, we concluded that the methylation profile of the SNRPN promoter (in blood) is not a useful biomarker for determining the predisposition of an individual to obesity. Additionally, we have confirmed that SNRPN methylation increases with age, which raises further questions regarding the role of SNRPN expression during the aging process.

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Genipa americana is a tropical tree species that is widely distributed in the humid tropical and subtropical regions of Central and South America. This study investigated Mendelian inheritance, genetic linkage, and genotypic disequilibrium at six microsatellite loci developed for G. americana. Adult trees (188) and regenerants (163) were sampled and genotyped in a fragmented population of the species. We also genotyped open-pollinated seeds from 12 seed-trees during reproductive events in 2010 and 2011. Significant deviations from the expected 1:1 Mendelian segregation were detected in 29.5% of the tests. Significant genetic linkage between pairwise loci was detected in 54.4% of the tests, but no genotypic disequilibrium was detected between pairwise loci for adult trees and regenerants. Overall, the results indicate that the six loci analyzed may be used in studies of G. americana's genetic diversity and structure, its mating system, and in parentage analyses.

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High-resolution melting (HRM) is considered an inexpensive, rapid, and attractive methodology for methylation analysis. In the application of the polymerase chain reaction (PCR) to methylation analysis, amplification efficiencies are biased towards unmethylated, rather than methylated, templates: a phenomenon known as PCR bias. To overcome PCR bias, primers that include CpG site(s) and are fully complementary to the methylated sequence have been proposed. However, genes mapped within imprinted regions usually present higher methylation levels, and an unusual PCR bias towards the methylated template can therefore arise. The manipulation of primer affinity attempts to overcome this problem. We attempted to show that mismatches at the primer's methylated binding sites increase the area between the 50 and 100% methylation plots on the melting curves, and may increase HRM accuracy for samples that have high methylation levels. Sets of primers for imprinted genes that included CpG sites at their binding sequences were designed, and were complementary to methylated or unmethylated templates. Primers fully complementary to methylated templates produced a very small area between the 50 and 100% methylation plots. When using primers that were fully complementary to the unmethylated sequence, we were able to increase the area between the 50 and 100% methylation plots. Therefore, when samples are highly methylated, such as targets in genes mapped in imprinted regions, we propose that primers should favor amplification of the rarest, unmethylated sequence. Primers may be designed to include one CpG at its binding site and be fully complementary to the unmethylated template.

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Salmonellosis is an infection caused by specific or non specific serotypes of theSalmonella genus, responsible for losses in the poultry industry. Fowl typhoid, caused by S. Gallinarum (SG) is important because it causes elevated mortality in adult birds, leading to economic losses in the poultry industry. This study aimed at quantifying the number of viable SG cells in the liver, spleen, lung, cecum, and reproductive tract (ovary and testicles) of experimentally inoculated Japanese quails (Coturnix coturnix), as well as SG shedding in their feces. One hundred and two Japanese quails, with four months of age at the beginning of the experiment, were used. The birds were inoculated with three bacterial cultures containing different concentrations (6x104CFU/0.1mL, 2x105 CFU/0.4mL, or 5x106CFU/0.2mL) of SG resistant to nalidixic acid. On days 1, 4, 7, and 14 after the inoculation (dpi) individual cloacal swabs were collected from six birds per group, which were subsequently sacrificed for organ sampling. The swab samples were streaked directly on plates containing brilliant green agar and nalidixic acid (VBNal). Samples that were negative after 24h, were streaked again. The collected organs were individually macerated and transferred to buffered peptone water at 0.1%. The solutions were immediately diluted serially for CFU counting in VBNal. SG was successfully recovered from one quail, which was inoculated with 2x105 CFU/0.4mL, and from five quails of the group inoculated with 5x106CFU/0.2mL inoculum. All of the analyzed cloacal swab samples were negative. Therefore, this study demonstrated it was difficult to isolate SG from the analyzed organs and that it was not possible to recover thepathogen in the cloacal swabs collected from inoculated quails. These results may be explained by the absence of flagella in SG, inducing weak intestinal immune response in the beginning of the infection and preventing its isolation in cloacal swab samples. The low positivity rate of the analyzed organs may be due to the immune status of the euthanized birds, since the SG dissemination in the animal organism occurs mostly close to death, which was observed in the birds found dead during the experiment.

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Salmonellosis is an infection caused by specific or non specific serotypes of theSalmonella genus, responsible for losses in the poultry industry. Fowl typhoid, caused by S. Gallinarum (SG) is important because it causes elevated mortality in adult birds, leading to economic losses in the poultry industry. This study aimed at quantifying the number of viable SG cells in the liver, spleen, lung, cecum, and reproductive tract (ovary and testicles) of experimentally inoculated Japanese quails (Coturnix coturnix), as well as SG shedding in their feces. One hundred and two Japanese quails, with four months of age at the beginning of the experiment, were used. The birds were inoculated with three bacterial cultures containing different concentrations (6x104CFU/0.1mL, 2x105 CFU/0.4mL, or 5x106CFU/0.2mL) of SG resistant to nalidixic acid. On days 1, 4, 7, and 14 after the inoculation (dpi) individual cloacal swabs were collected from six birds per group, which were subsequently sacrificed for organ sampling. The swab samples were streaked directly on plates containing brilliant green agar and nalidixic acid (VBNal). Samples that were negative after 24h, were streaked again. The collected organs were individually macerated and transferred to buffered peptone water at 0.1%. The solutions were immediately diluted serially for CFU counting in VBNal. SG was successfully recovered from one quail, which was inoculated with 2x105 CFU/0.4mL, and from five quails of the group inoculated with 5x106CFU/0.2mL inoculum. All of the analyzed cloacal swab samples were negative. Therefore, this study demonstrated it was difficult to isolate SG from the analyzed organs and that it was not possible to recover thepathogen in the cloacal swabs collected from inoculated quails. These results may be explained by the absence of flagella in SG, inducing weak intestinal immune response in the beginning of the infection and preventing its isolation in cloacal swab samples. The low positivity rate of the analyzed organs may be due to the immune status of the euthanized birds, since the SG dissemination in the animal organism occurs mostly close to death, which was observed in the birds found dead during the experiment.(AU)

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Generally, the medicinal plants have antifungal substances that can be used for the plant protection against phytopathogens. The objective of this study was to know the efficiency of aqueous extracts from medicinal plants against the major etiological agents of coffee tree. The aqueous extracts used were extracted from bulbs of Allium sativum, leaves of Vernonia polysphaera, Cymbopogon citratus, Cymbopogon nardus, Cordia verbenacea, Eucalyptus citriodora, Ricinus communis, Azadirachta indica, Piper hispidinervum and flower buds of Syzygium aromaticum. The etiological agents considered for this study were Cercospora coffeicola, Colletotrichum gloeosporioides, Fusarium oxysporum, Phoma tarda, Rhizoctonia solani and Hemileia vastatrix. The screening for harmful extracts was done based on mycelial growth and conidial germination inhibition. All experiments performed were in vitro conditions. The inhibition of mycelial growth was performed mixing the extracts with the PDA. This mixture was poured in Petri dishes. On the center of the dishes was added one PDA disc with mycelium. It was incubated in a chamber set to 25ºC. The evaluation was done daily by measuring the mycelial growth. The germination assessment was also performed with Petri dishes containing agar-water medium at 2%. These were incubated at 25ºC for 24 hours. After this period the interruption of germination was performed using lactoglycerol. The experiments were conducted in a completely randomized design. The most effective plant extracts against the micelial growth and conidial germination were V. polysphaera, S. aromaticum and A. sativum.

Geralmente, as plantas medicinais têm substâncias antifúngicas que podem ser utilizadas para a proteção das plantas contra fitopatógenos. O objetivo deste estudo foi conhecer a eficiência de extratos aquosos de plantas medicinais contra os principais agentes etiológicos do cafeeiro. Os extratos aquosos utilizados foram extraídos de bulbos de Allium sativum, folhas de Vernonia polysphaera, Cymbopogon citratus, Cymbopogon nardus, Cordia verbenacea, Eucalyptus citriodora, Ricinus communis, Azadirachta indica, Piper hispidinervum e botões florais de Syzygium aromaticum. Os agentes etiológicos considerados neste estudo foram Cercospora coffeicola, Colletotrichum gloeosporioides, Fusarium oxysporum, Phoma tarda, Rhizoctonia solani e Hemileia vastatrix. A triagem dos extratos foi realizada com base no crescimento micelial e na inibição da germinação de conídios. Todos os experimentos foram realizados em condições in vitro. A inibição do crescimento micelial foi realizada misturando-se os extratos com PDA. Esta mistura foi vertida em placas de Petri. No centro das placas foi adicionado um disco de PDA com micélio. Incubou-se em câmara programada para 25°C. A avaliação foi feita diariamente através da medição do crescimento micelial. O experimento sobre a germinação também foi realizado com placas com meio ágar-água a 2%. Estas foram incubadas durante 24 horas. Após este período, a interrupção da germinação foi realizada utilizando lactoglicerol. Os experimentos foram conduzidos em delineamento inteiramente casualizado. Os extratos de plantas mais eficazes contra o crescimento micelial e germinação de conídios foram V. polysphaera, S. aromaticum e A. sativum.

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Cariniana legalis is one of the largest tropical trees with a wide distribution in the Brazilian Atlantic rainforest. We investigated the Mendelian inheritance, genetic linkage, and genotypic disequilibrium at seven microsatellite loci specifically isolated for C. legalis, and at two previously developed heterologous microsatellite loci. Forty to 100 open-pollinated seeds were collected from 22 seed-trees in two populations. Using the Bonferroni correction, no remarkable deviations from the expected Mendelian segregation, linkage, or genotypic disequilibrium were detected in the nine loci studied. Only 3.7% of the tests were significant for investigations of the Mendelian proportions. On the other hand, only 2.8% of tests for linkage detection showed significance. In addition, among all pairwise tests used for investigating linkage disequilibrium, significance was found in 9.7% of the locus pairs. Our results show clear evidence that the nine simple sequence repeat loci can be used without restriction in genetic diversity, mating system, and parentage analyses.

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Over the past century, the Brazilian Atlantic forest has been reduced to small, isolated fragments of forest. Reproductive isolation theories predict a loss of genetic diversity and increases in inbreeding and spatial genetic structure (SGS) in such populations. We analysed eight microsatellite loci to investigate the pollen and seed dispersal patterns, genetic diversity, inbreeding and SGS of the tropical tree Copaifera langsdorffii in a small (4.8 ha), isolated population. All 112 adult trees and 128 seedlings found in the stand were sampled, mapped and genotyped. Seedlings had significantly lower levels of genetic diversity (A=16.5±0.45, mean±95% s.e.; H(e)=0.838±0.006) than did adult trees (A=23.2±0.81; H(e)=0.893±0.030). Parentage analysis did not indicate any seed immigration (m(seeds)=0) and the pollen immigration rate was very low (m(pollen)=0.047). The average distance of realized pollen dispersal within the stand was 94 m, with 81% of the pollen travelling <150 m. A significant negative correlation was found between the frequency and distance of pollen dispersal (r=-0.79, P<0.01), indicating that short-distance pollinations were more frequent. A significant SGS for both adults (∼50 m) and seedlings (∼20 m) was also found, indicating that most of the seeds were dispersed over short distances. The results suggested that the spatial isolation of populations by habitat fragmentation can restrict seed and pollen gene flow, increase SGS and affect the genetic diversity of future generations.

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