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1.
Artigo em Inglês | MEDLINE | ID: mdl-35321851

RESUMO

For amphibian species that display external fertilization in an aquatic environment, hypoosmotic shock to sperm cells can quickly result in damage to cellular structure and function. This study sought to determine how fertilization media osmolality, temperature, and time impact the stability of the mitochondrial vesicle's association with the sperm head and thus motility and quality of forward progression. The presence of the mitochondrial vesicle and its relationship with sperm motility and quality of forward progression were analyzed in sperm samples from the Fowler's toad (Anaxyrus fowleri) (n = 10) when held for six hours under two temperatures and four osmolalities. Results indicated that the presence of the mitochondrial vesicle is needed for sperm motility over time (p < 0.001), where higher osmolalities (p < 0.001) and lower temperatures (p < 0.001) correlated with maintaining the vesicle attachment to the spermatozoa. The higher osmolality of spermic urine was the most important factor for maintaining higher quality of forward progressive motility (p < 0.01) of spermatozoa. Sperm samples held at 4 °C and 40 mOsm/kg had the longest half-life for motility (540 min) and quality of forward progression (276 min), whereas sperm held at 22 °C and 2.5 mOsm/kg had the shortest half-life for motility (7 min) and quality of forward progression (18 min). Special attention should be given to the osmolality and temperature of fertilization solutions, or breeding tank water, when developing cold storage protocols for toad sperm or reproducing animals to ensure the retention of the mitochondrial vesicle for maximum fertilization capability.


Assuntos
Motilidade dos Espermatozoides , Espermatozoides , Animais , Bufonidae/fisiologia , Criopreservação , Masculino , Concentração Osmolar , Espermatozoides/fisiologia
2.
Comp Med ; 71(2): 177-187, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33579397

RESUMO

Aging of the immune system is characterized by the loss of naïve T-cells, increased inflammation, and immune function impairment. Chronic infection with cytomegalovirus is thought to play a role in age-related changes in immunity. Therefore, to assess the effect of pathogens such as cytomegalovirus on the immune system, we determined lymphocyte populations and inflammatory markers over a 3-y period in captive, middle-age baboons, with various exposure to pathogens and shedding pressure. Groups included SPF (i.e., pathogen-negative; n = 14); large-group, conventionally housed (CONV LG; pathogen- positive; n = 14), and small-group, conventionally housed (CONV SM; pathogen-positive; n = 7). All baboon groups showed a decrease in CD45RA+ CD28+ (i.e., naive) cells over time during middle age, but the rate of decline appeared faster in CONV LG baboons than in the other groups. In addition, the reduction in CD45RA+ CD28+ cells in the CONV LG baboons coincided with higher IgG levels against baboon cytomegalovirus, increased serum cortisol concentration, and a greater inflammatory phenotype. The results of this project support a role for cytomegalovirus infection in immune system alterations in middle-aged baboons.


Assuntos
Infecções por Citomegalovirus , Papio anubis , Envelhecimento , Animais , Papio , Linfócitos T
3.
Comp Med ; 69(1): 55-62, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30704552

RESUMO

Cytomegalovirus (CMV) is a common chronic herpesvirus found in humans and numerous other mammalian species. In people, chronic viruses like CMV can alter overall health and immunity and pose a serious risk for those with an inadequate immune system. In addition, CMV plays an important role in animal health, and could affect the health of vulnerable populations, like endangered species. Previous studies found a high rate of CMV seropositivity among adult baboons (Papio anubis), and results from our laboratory revealed that baboon CMV (BaCMV) seropositivity was correlated with altered immune cell populations. In the current study, we further characterized BaCMV infection in normal, adult baboons. Analysis of blood samples from baboons (age, 6 to 26 y) revealed a low overall prevalence of detectable of BaCMV DNA, with a higher detection rate in aged baboons (older than 15 y). Furthermore, data suggest that individual baboons maintain similar rates of recurrence and levels of BaCMV shedding in saliva over time. Finally, we evaluated multiple commercially available assays for antihuman CMV IgG and IgM for use with baboon sera. Results of this study will improve our understanding of BaCMV and may be directly relevant to other closely related species.


Assuntos
Infecções por Citomegalovirus/veterinária , Doenças dos Macacos/patologia , Papio anubis , Fatores Etários , Animais , Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/patologia , DNA Viral/sangue , Doenças dos Macacos/sangue , Doenças dos Macacos/imunologia , Saliva/virologia , Eliminação de Partículas Virais
4.
Mol Reprod Dev ; 84(1): 55-66, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27879029

RESUMO

Little is known about the ADAMTS (a disintegrin and metalloproteinase with thrombospondin motifs) family of extracellular proteases in ovarian follicles of non-rodent species, particularly in theca cells. In the present study, temporal changes in the abundance of mRNA encoding four ADAMTS subtypes and hormonal regulation of mRNA encoding two subtypes were investigated in theca interna cells during the periovulatory period in cattle. Gonadotropin-releasing hormone (GnRH) was injected into animals to induce a luteinizing hormone (LH)/follicle-stimulating hormone (FSH) surge, and follicles were obtained at 0 hr post-GnRH (preovulatory) or at 6, 12, 18, or 24 hr (periovulatory). ADAMTS1, -2, -7, and -9 transcript abundance was then determined in the isolated theca interna. ADAMTS1 and -9 mRNA levels were up-regulated at 24 hr post-GnRH, whereas ADAMTS2 mRNA was higher at 12-24 hr post-GnRH and ADAMTS7 mRNA increased transiently at 12 hr post-GnRH compared to other time points. Subsequent in vitro experiments using preovulatory theca interna (0 hr post-GnRH) showed that application of LH in vitro can mimic the effects of the gonadotropin surge on mRNAs encoding ADAMTS1 and -9 and that progesterone/progesterone receptor and/or prostaglandins may regulate the levels of mRNA encoding ADAMTS1 and -9 in theca interna, downstream of the LH surge. Time- and subtype-specific changes in ADAMTS mRNA abundance in vivo, and their regulation in vitro by hormones, indicate that ADAMTS family members produced by theca cells may play important roles in follicle rupture and the accompanying tissue remodeling in cattle. Mol. Reprod. Dev. 84: 55-66, 2017. © 2016 Wiley Periodicals, Inc.


Assuntos
Proteínas ADAMTS/biossíntese , Hormônio Luteinizante/farmacologia , Prostaglandinas/metabolismo , RNA Mensageiro/biossíntese , Receptores de Progesterona/metabolismo , Células Tecais/metabolismo , Animais , Bovinos , Feminino , Células Tecais/citologia
5.
Theriogenology ; 85(4): 671-7, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26559471

RESUMO

Reproducing giant pandas (Ailuropoda melanoleuca) remains the most challenging aspect of managed care of this species. However, advancement in knowledge stemming from basic science research on the giant panda has facilitated a growth in the population. Here, we report the successful application of reproductive technologies, including noninvasive hormone monitoring, behavioral/morphometric observations, ultrasonographic evaluations, and acute phase protein assessment, in an individual female. By applying these approaches to one female, we report the practicality and usefulness of a multidisciplinary approach to reproductive care of the species. In addition, the utilization of various technologies across multiple physiological states also provided us an opportunity to record previously understudied events, such as maternal response to weaning and growth of a conceptus.


Assuntos
Lactação/fisiologia , Prenhez , Ursidae/fisiologia , Animais , Estrogênios/sangue , Ciclo Estral , Feminino , Fertilização/fisiologia , Fase Luteal , Gravidez , Prenhez/fisiologia , Progestinas/sangue , Desmame
6.
PLoS One ; 9(9): e107167, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25244034

RESUMO

The human immune system undergoes age-related changes that can lead to increased disease susceptibility. Using the baboon as a model for human immune system aging, we examined age-related changes in relative and absolute numbers of T cell subpopulations, cytomegalovirus (CMV) titer and markers of inflammation. In addition, the effect of gender, social status and peer group on lymphocyte subpopulations was determined. Relative and absolute numbers of total lymphocytes (CD3+), T helper cells (CD4+), and cytotoxic T cells (CD8+) increased with age. The proportion of naïve T cells (CD45RA+) decreased, while the total number of cells negative for the co-stimulatory receptor, CD28 (CD28-) increased in an age-dependent manner. Furthermore, CMV titers were negatively correlated with the number of naive CD4+ cells. IL-6 and cortisol concentration were also negatively associated with T cell subpopulations. Additionally, socially dominant baboons exhibited decreases in naïve CD4+ and CD8+ cells (by 65% and 52%, respectively) compared to subordinate animals. These results suggest that factors such as CMV exposure and inflammation may contribute to the age-related decline in immune health and indicate that factors like social status should be considered when studying immunosenescence in animal models.


Assuntos
Envelhecimento/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Infecções por Citomegalovirus/imunologia , Citomegalovirus , Inflamação/imunologia , Subpopulações de Linfócitos T/imunologia , Fatores Etários , Envelhecimento/sangue , Envelhecimento/patologia , Animais , Biomarcadores/sangue , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Infecções por Citomegalovirus/sangue , Infecções por Citomegalovirus/patologia , Hidrocortisona/sangue , Sistema Imunitário/imunologia , Sistema Imunitário/patologia , Inflamação/sangue , Inflamação/patologia , Interleucina-6/sangue , Papio , Subpopulações de Linfócitos T/patologia
7.
Biol Lett ; 8(5): 695-7, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-22219389

RESUMO

Hormone analysis is a precise and widely accepted tool for monitoring reproductive function and responses to stressors. Although hormones are present and can be measured in various biological matrices, non-invasive methods have gained popularity over the past 30 years as a more practical approach for assessing ovarian, testicular and, more recently, adrenocortical activity in intractable wildlife species. Non-invasive hormone monitoring also has been key to understanding biological mechanisms related to observed behaviours of captive and free-ranging animals. Despite the increasing popularity of this research field, wildlife endocrinologists have not had a specific forum for sharing and discussing their latest findings, technical developments and common challenges. To provide such a communication platform, the International Society for Wildlife Endocrinology (ISWE) was established in 2010, followed by an international meeting held on 3-4 November 2011 at the Toronto Zoo, Canada. Over several sessions, keynote speakers and participants discussed recent developments of new and innovative methods for hormone monitoring, as well as the latest advances in basic endocrinology as applied to adrenal function, reproductive physiology, animal health, ecology and evolution. Here, we introduce ISWE to the scientific community and discuss how this new society will serve as a resource for wildlife endocrinologists worldwide.


Assuntos
Animais Selvagens/fisiologia , Endocrinologia/métodos , Reprodução/fisiologia , Córtex Suprarrenal/fisiologia , Bem-Estar do Animal , Animais , Animais de Zoológico , Canadá , Conservação dos Recursos Naturais , Hormônios/fisiologia
8.
PLoS One ; 6(7): e21159, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21765892

RESUMO

After ovulation, non-pregnant female giant pandas experience pseudopregnancy. During pseudopregnancy, non-pregnant females exhibit physiological and behavioral changes similar to pregnancy. Monitoring hormonal patterns that are usually different in pregnant mammals are not effective at determining pregnancy status in many animals that undergo pseudopregnancy, including the giant panda. Therefore, a physiological test to distinguish between pregnancy and pseudopregnancy in pandas has eluded scientists for decades. We examined other potential markers of pregnancy and found that activity of the acute phase protein ceruloplasmin increases in urine of giant pandas in response to pregnancy. Results indicate that in term pregnancies, levels of active urinary ceruloplasmin were elevated the first week of pregnancy and remain elevated until 20-24 days prior to parturition, while no increase was observed during the luteal phase in known pseudopregnancies. Active ceruloplasmin also increased during ultrasound-confirmed lost pregnancies; however, the pattern was different compared to term pregnancies, particularly during the late luteal phase. In four out of the five additional reproductive cycles included in the current study where females were bred but no birth occurred, active ceruloplasmin in urine increased during the luteal phase. Similar to the known lost pregnancies, the temporal pattern of change in urinary ceruloplasmin during the luteal phase deviated from the term pregnancies suggesting that these cycles may have also been lost pregnancies. Among giant pandas in captivity, it has been presumed that there is a high rate of pregnancy loss and our results are the first to provide evidence supporting this notion.


Assuntos
Ceruloplasmina/urina , Perda do Embrião/veterinária , Pseudogravidez/urina , Ursidae/urina , Animais , Biomarcadores/urina , Cruzamento , Perda do Embrião/urina , Feminino , Inflamação/patologia , Fase Luteal , Modelos Biológicos , Progestinas/urina
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