Cryopreservation efficiency of red-rumped agouti (Dasyprocta leporina) sperm obtained from different origins through epididymal retrograde flushing or electroejaculation.

This study investigated whether the origin of sperm (epididymal vs. ejaculate) affects the cryopreservation efficiency in agouti (Dasyprocta leporina). Five sexually mature agoutis underwent electroejaculation, resulting in obtaining four semen samples. After 15 days, the same animals were euthanized, and through retrograde flushing, sperm samples were obtained from the epididymis tails. In both collection methods, samples were evaluated for sperm parameters (sperm concentration, motility, vigor, membrane integrity, osmotic response, and morphology). Then, samples were diluted in ACP 109c, added with 20% egg yolk, and a final concentration of 6% glycerol. Finally, the samples were packaged in 0.25 mL straws and frozen in liquid nitrogen. After one week, samples were thawed and evaluated in the same way as fresh samples, with the addition of membrane integrity analysis using fluorescent probes (C-FDA/PI) and computerized analysis (CASA). Immediately after obtaining the sperm, samples obtained directly from the epididymis presented higher values (P ≤ 0.05) than those obtained by electroejaculation concerning the parameters of volume, sperm concentration, and total number of sperm (1,398.25 ± 206.0 x106 and 184.5 ± 78.0 x106 sperm). On the other hand, in the classical evaluation of the other sperm parameters and the computerized analysis (CASA) after thawing, such as total motility, no statistical differences were observed between sperm from both origins (ejaculate: 16.7 ± 8.2% and epididymal: 24.8 ± 12.0%, P > 0.05). This demonstrates the possibility of direct application of the cryopreservation protocol for agouti (D. leporina) sperm obtained via the epididymis or ejaculate.

Reproduction in agouti (Dasyprocta spp .): A review of reproductive physiology for developing assisted reproductive techniques.

Dasyprocta spp. (agouti) include wild rodents with highlighted ecological and economic importance, and are considered experimental models for endangered hystricognath rodents. Of late, development of techniques to conserve their genetic material as well as the formation of biobanks is increasing. In this context, this review describes the main advances in the knowledge of the reproductive morphophysiological specificities of agouti as well as the development and improvement of assisted reproductive techniques aimed at conservation, multiplication, and exploitation of their reproductive potential under captivity.

Estimating the binding ability of collared peccary (Pecari tajacu Linnaeus, 1758) sperm using heterologous substrates.

In collared peccaries, the development of artificial insemination (AI) is scarce, requiring search for alternative methods for the evaluation of sperm fertilizing ability. Thus, the aims of this study were to estimate the binding capability of collared peccaries sperm, using swine oocytes and the egg perivitelline membrane, and to evaluate the prognostic value of sperm parameters on the in vitro interactions among sperm and heterologous substrates. Eleven ejaculates were collected by eletroejaculation and evaluated for viability and morphology by light microscopy, for functionality by hypo-osmotic swelling test, for plasma membrane integrity by epifluorescence microscopy, and for sperm motility by computerized analysis. Subsequently, for analysis of the in vitro interactions, sperm samples were cultured in an incubation medium with swine oocytes and egg perivitelline membrane for 18 h and 20 min, respectively, at 38.5 °C and humidified atmosphere. The sperm-oocyte interaction rate was 100% with sperm penetrating 19.8+ 5.5% of oocytes. The average values of bound sperm and penetrated sperm per oocyte were 39.4 + 4.6 and 2.5 + 0.7, respectively. Already for perivitelline membrane binding assay, all samples presented sperm bound (100%) with average of 140.6 ± 19.4 bound sperm (range 33.9-308.7). Moreover, positive correlations were observed for the number of sperm bound to swine oocytes and osmotic response (r = 68.5%; P = 0.02), membrane integrity (r = 65.1%; P = 0.03), and straightness (r = 66.5%; (P = 0.03), as weel as for the number of sperm bound to egg perivitelline membrane and sperm viability (r = 74.0%; P = 0.01), total motility (r = 63.6%; P = 0.04), and linearity (r = 70.5%; P = 0.02). Finally, a negative correlation among slow (r = -80.5%; P = 0.01) and static (r = -84.3%; P = 0.01) sperm with the egg perivitelline membrane was observed. In conclusion, swine oocytes and perivitelline membrane can be used as indicators for the functional evaluation of the binding capability of sperm derived from collared peccaries. These tests could be incorporated into the routine of semen technologies.

Sperm characteristics following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins in the collared peccary (Pecari tajacu).

The aim of the current study was to compare sperm quality characteristics of the collared peccary (Pecari tajacu) following freezing in extenders supplemented with whole egg yolk and different concentrations of low-density lipoproteins (LDL). Semen from 11 adult males was obtained by electroejaculation and evaluated for sperm motility, vigor, morphology as well as membrane integrity analyzed by the hypo-osmotic swelling (HOS) test and a fluorescent staining. Moreover, the semen was diluted in a Tris-based extender containing 20% egg yolk (control group) or 5, 10 or 20% LDL (treatment groups). The semen samples were frozen in liquid nitrogen and thawed in a water bath for 60s at 37°C. The treatments did not affect (p>0.05) sperm vigor, morphology or membrane integrity analyzed by the HOS test. However, post-thaw sperm motility was significantly higher (p<0.05) in the extender supplemented with 20% LDL (36.4 ± 5.3%) compared with the egg yolk extender and extender supplemented with 10% LDL. Furthermore, the percentage of membrane-intact frozen-thawed spermatozoa analyzed by the fluorescent staining was significantly higher (p<0.05) in the extender supplemented with 20% LDL (27.4 ± 6.5%) than in the other groups. In conclusion, 20% LDL can be used to substitute the whole egg yolk as a cryoprotective additive for freezing semen of the collared peccary.

Estrous synchronization in captive collared peccaries (Pecari tajacu) using a prostaglandin F2α analog.

We verify the efficiency of a protocol for estrus synchronization in captive female collared peccaries (Pecaricari tajacu) using the prostaglandin analog D-cloprostenol. Five adult female collared peccaries received an intramuscular administration of 60 µg D-cloprostenol, which procedure was repeated after a 9-day interval. For 10 days after second the D-cloprostenol administration, females were monitored for changes in external genitalia, ovarian ultrasonography, vaginal cytology and reproductive hormonal dosage. As a result, four females synchronized their estrous at 9.5 ± 0.5 days after the second administration of the prostaglandin analog. Such females showed external signs of estrus, including vulvar opening, hyperemic vaginal mucosa, and vaginal mucus, concomitant with an increase in the proportion of superficial cells (52.2 ± 9.9%) verified through vaginal cytology. An estrogen peak of 22.7 ± 3.4 pg/ml was detected by hormonal dosage, and the presence of anechoic follicles measuring 0.29 ± 0.05 × 0.32 ± 0.07 mm were detected in the ovary by ultrasonography. Given these findings, we suggest that D-cloprostenol may be effective for use in estrus synchronization in collared peccaries.

Relações entre a câmara de Neubauer a espectrofotometria utilizadas para a determinação da concentração espermática de catetos (Pecari tajacu) / Relationship between Neubauer counting chamber and spectrophotometer used for the sperm concentration determination in collared peccaries (Pecari tajacu)

Em ejaculados provenientes de 28 catetos, verificou-se a existência de relações entre a concentração espermática determinada por meio da câmara de Neubauer e a tramitância observada por espectrofotometria, utilizando comprimentos de onda variando de 530 a 590nm. Os ejaculados apresentaram uma concentração média de 283,9±30,8x106 espermatozoides mL-1, com variação de 30 a 640x106 espermatozoides mL-1. Os valores para tramitância variaram entre 36,9 a 96,3, nos diferentes comprimentos de onda. Não foram detectadas relações significativas entre os dois métodos (P>0,05). Dessa forma, não se recomenda a espectrofotometria para os procedimentos de rotina na determinação da concentração espermática em catetos.

In ejaculates derived from 28 collared peccaries, we verified the existence of relationships between sperm concentration determined by the Neubauer counting chamber and the tramitance verified by spectrophotometer, under wavelengths varying from 530 to 590nm. Ejaculates presented a concentration of 283.9±30.8x106sperm m-1, varying from 30 to 640x106sperm mL-1. Values for tramitance varied from 36.9 to 96.3, under different wavelengths. No significant relationship was verified between two methods (P>0.05). Thus, the spectrophotometer is not recommended for routine procedures of sperm concentration measurement in collared peccaries.

Influence of recovery method and centrifugation on epididymal sperm from collared peccaries (Pecari tajacu Linnaeus, 1758).

In order to establish protocols for gamete recovery from accidentally killed wild animals, or to take advantage of those slaughtered by captive breeders, we assess the influence of two methods on the recovery of epididymal sperm from collared peccaries, and verify the effect of centrifugation on such gametes. Genitalia from nine animals were used. For each animal, one epididymis was processed by flotation and the other was processed by retrograde flushing, both using a buffered media based on Tris. Following recovery, sperm were evaluated for motility, vigor, viability, functional membrane integrity, and morphology. A 1-mL aliquot of each sample was centrifuged, the supernatant removed, and the pellet suspended and evaluated as fresh samples. The sperm characteristics did not differ between the samples collected by flotation or retrograde flushing (P < 0.05). Centrifugation promoted an increase in head and tail defects, thus reducing the percentage of viable sperm (P < 0.05). No other parameter assessed for both methods was affected by centrifugation. In conclusion, epididymal sperm from collared peccaries can be efficiently collected through flotation or retrograde flushing, but not when either is followed by centrifugation.

Sandflies (Psychodidae: Phlebotominae) survey in an urban transmission area of visceral leishmaniasis, Northeastern Brazil.

Visceral leishmaniasis (VL) is a major public health challenge in Brazil, especially in states where it is endemic. The aim of this study was to investigate the relationship of sand fly population density with environmental variables (temperature, rainfall and relative humidity) in urban areas of the city of Mossoró, Rio Grande do Norte, Northeastern Brazil. Sand flies were captured with Center Disease Control (CDC) traps installed monthly in the intra and peridomicile of three houses. Data analysis was based on the chi-square test and linear regression. A total of 7,347 sand flies were captured, being 93.85% Lutzomyia longipalpis and 6.15% Lutzomyia evandroi. Sand flies were more commonly found in the peridomicile and there was no difference between the number of males and females. The variables rainy season as well as relative humidity and rainfall, alone or together, did not have an effect on sand fly population density. However, high temperatures had a negative effect. The study of the behavior of sand flies in specific units of endemic areas can provide input to public health authorities for planning appropriate VL vector control measures.

Sandflies (Psychodidae: Phlebotominae) survey in an urban transmission area of visceral leishmaniasis, Northeastern Brazil / Pesquisa de flebotomíneos (Psychodidae: Phlebotominae) em área urbana de transmissão de leishmaniose visceral no Nordeste do Brasil

Visceral leishmaniasis (VL) is a major public health challenge in Brazil, especially in states where it is endemic. The aim of this study was to investigate the relationship of sand fly population density with environmental variables (temperature, rainfall and relative humidity) in urban areas of the city of Mossoró, Rio Grande do Norte, Northeastern Brazil. Sand flies were captured with Center Disease Control (CDC) traps installed monthly in the intra and peridomicile of three houses. Data analysis was based on the chi-square test and linear regression. A total of 7,347 sand flies were captured, being 93.85 percent Lutzomyia longipalpis and 6.15 percent Lutzomyia evandroi. Sand flies were more commonly found in the peridomicile and there was no difference between the number of males and females. The variables rainy season as well as relative humidity and rainfall, alone or together, did not have an effect on sand fly population density. However, high temperatures had a negative effect. The study of the behavior of sand flies in specific units of endemic areas can provide input to public health authorities for planning appropriate VL vector control measures.

A leishmaniose visceral (LV) é um grande desafio para a saúde pública no Brasil, particularmente nos estados onde é endêmica. O objetivo deste estudo foi verificar a relação da densidade populacional de flebotomíneos com as variáveis ambientais (temperatura, precipitação de chuva e umidade relativa do ar) em bairros urbanos de Mossoró, Rio Grande do Norte. Os flebotomíneos foram capturados com armadilhas CDC instaladas mensalmente no intra e peridomicílio de três casas. A análise dos dados foi baseada no teste Qui-quadrado e na regressão linear. Foram capturados 7.347 flebotomíneos, sendo 93,85 por cento Lutzomyia longipalpis e 6,15 por cento Lutzomyia evandroi. Os flebotomíneos foram encontrados mais comumente no peridomicílio e nenhuma diferença significativa entre o número de machos e fêmeas foi observada. As variáveis estação chuvosa, bem como a umidade relativa e precipitação de chuva, associadas ou isoladas, não influenciou a densidade populacional dos flebotomíneos. No entanto, a alta temperatura afetou essa densidade de forma negativa. Portanto, este estudo específico em áreas endêmicas é importante, porque as agências de Saúde Pública podem usar essas informações para um planejamento adequado das medidas de controle de vetores LV.

Monitoring of Lutzomyia longipalpis Lutz & Neiva, 1912 in an area of intense transmission of visceral leishmaniasis in Rio Grande do Norte, Northeast Brazil.

Urban increase of visceral leishmaniasis (VL) in Brazil is associated with the adaptation of its vector, Lutzomyia longipalpis, to environments modified by humans. The present study reports the results of an entomological monitoring of L. longipalpis and the effect of environmental variables on its population density. Sandflies were captured in the municipality of Mossoró, State of Rio Grande do Norte, Northeastern Brazil, from January 2005 to December 2006. Two CDC light traps were placed monthly for four consecutive nights in the peridomicile of selected households. Data analysis was based on the chi-square test and linear regression. A total of 2,087 sandflies were captured, 99.86% of which were L. longipalpis. A higher proportion of females were captured (p < 0.05). Monthly analysis of the variables temperature, relative humidity and rainfall did not show a significant influence on population density. However, there were seasonal differences: approximately 70% of sand flies were captured during the rainy season (p < 0.05). The predominant species, L. longipalpis, is present in substantial number, representing a public health risk. Therefore, because of higher prevalence during the rainy season, we recommend intensified VL control measures before and during this season to reduce the risk of disease transmission.

Monitoring of Lutzomyia longipalpis Lutz & Neiva, 1912 in an area of intense transmission of visceral leishmaniasis in Rio Grande do Norte, Northeast Brazil / Monitoramento de Lutzomyia longipalpis Lutz & Neiva, 1912 em área de transmissão intensa de leishmaniose visceral no Rio Grande do Norte, Nordeste do Brasil

Urban increase of visceral leishmaniasis (VL) in Brazil is associated with the adaptation of its vector, Lutzomyia longipalpis, to environments modified by humans. The present study reports the results of an entomological monitoring of L. longipalpis and the effect of environmental variables on its population density. Sandflies were captured in the municipality of Mossoró, State of Rio Grande do Norte, Northeastern Brazil, from January 2005 to December 2006. Two CDC light traps were placed monthly for four consecutive nights in the peridomicile of selected households. Data analysis was based on the chi-square test and linear regression. A total of 2,087 sandflies were captured, 99.86 percent of which were L. longipalpis. A higher proportion of females were captured (p < 0.05). Monthly analysis of the variables temperature, relative humidity and rainfall did not show a significant influence on population density. However, there were seasonal differences: approximately 70 percent of sand flies were captured during the rainy season (p < 0.05). The predominant species, L. longipalpis, is present in substantial number, representing a public health risk. Therefore, because of higher prevalence during the rainy season, we recommend intensified VL control measures before and during this season to reduce the risk of disease transmission.

No Brasil, o crescimento urbano da leishmaniose visceral (LV) está associado com a adaptação do seu vetor, Lutzomyia longipalpis, aos ambientes modificados pelo homem. Este estudo relata a vigilância entomológica de L. longipalpis e os efeitos das variáveis ambientais sobre a sua densidade populacional. Os flebotomíneos foram capturados no município de Mossoró, Rio Grande do Norte, no Nordeste do Brasil, a partir de janeiro de 2005 a dezembro de 2006. Duas armadilhas tipo CDC foram colocadas mensalmente durante quatro noites consecutivas no peridomicílio das casas escolhidas. A análise dos dados foi baseada no teste Qui-quadrado e regressão linear. Um total de 2.087 flebotomíneos foram capturados, dos quais 99,86 por cento foram L. longipalpis. Mais fêmeas do que machos foram capturados (p < 0,05). Na análise mensal das variáveis ambientais a temperatura, umidade relativa e a chuva não tiveram impacto significativo sobre a densidade populacional de L. longipalpis. No entanto, houve diferenças sazonais: aproximadamente 70 por cento dos flebotomíneos foram capturados durante a estação chuvosa (p < 0,05). Assim, L. longipalpis, a espécie predominante, representa um risco à saúde pública. Portanto, devido à maior prevalência no período chuvoso, recomendamos intensificar as medidas de controle da LV antes e durante este período para reduzir o risco de transmissão da doença.