156 MONITORING SALIVARY TESTOSTERONE CONCENTRATIONS FROM CAPTIVE AMAZONIAN MANATEES (TRICHECHUS INUNGUIS): IS THERE SEASONAL PATTERN?

2011 ◽  
Vol 23 (1) ◽  
pp. 181 ◽  
Author(s):  
R. S. Amaral ◽  
F. C. W. Rosas ◽  
P. Viau ◽  
M. Nichi ◽  
V. M. F. da Silva ◽  
...  

Seasonality of reproduction in many nondomestic animal species appears to represent an accommodation to environmental variables, as food availability, in which influence reproductive success. Males can show a decrease of testicular size, sperm concentration, and serum concentration of testosterone because of food restriction. The Amazonian manatee (Trichechus inunguis, Mammalia: Sirenia) is a threatened aquatic mammal, endemic of the Amazon basin (South America), and is the only sirenian that occurs exclusively in fresh water. Although information is lacking about the reproductive endocrinology of free-ranging T. inunguis, they are considered seasonal breeders, with copulation and births occurring between December and July, coinciding with the increase in Amazon basin water levels and the period of most availability of food for the species (Best 1982 Biotropica 14, 76–78). Salivary steroid measurement is a noninvasive way to monitor steroid concentration, which is well correlated with the level of steroids in the serum. The aim of this study was to verify if testosterone concentrations of male T. inunguis kept in captivity, without variation of food availability, show a seasonal pattern. Were used 4 adult male Amazonian manatees kept in captivity in the Laboratory of Aquatic Mammals of the National Institute of Amazonian Research–LMA/INPA, Brazil. They were fed all year with paragrass and vegetables, at not less than 8% of body weight per day. For sample collection, the pool was drained and saliva was collected from mouth mucosa using a metal spoon. Samples were collected weekly for 12 weeks in 2 periods (March–June and September–November). Salivary testosterone was measured by RIA for total testosterone using an adapted protocol previously validated for the species (Amaral et al. 2009 J. Zoo Wildl. Med. 40, 458–465) The data were analysed in a 3 × 2 factorial design, where the factors were month (each 4 weeks = 1 month) and period, using GLM test for repeated-measures. The means of salivary androgen levels were 28.80 ± 18.56 pg mL–1 and 30.77 ± 16.76 pg mL–1 for first and second periods, respectively. There were no significant main effects of month (P = 0.454), period (P = 0.607), or interaction between factors (P = 0.635). These results suggest that captive male Amazonian manatees apparently do not show reproductive seasonality. However, it is recommended to verify the existence of variation in testicular size and sperm concentration. This finding is important information for the future reproductive management of captive Amazonian manatee. The authors thank PREVET staff for help with the samples collection, and FAPESP (2008/05760-5), CNPq (Universal 475596/2009-9), Petrobras Ambiental (Projeto Mamíferos Aquáticos da Amazônia: Conservação e Pesquisa), and AMPA for the financial support.

2015 ◽  
Vol 87 (3) ◽  
pp. 194 ◽  
Author(s):  
Mehmet Zeynel Keskin ◽  
Salih Budak ◽  
Tuǧba Zeyrek ◽  
Orçun Çelik ◽  
Oguz Mertoglu ◽  
...  

Objective: The aim of this study was to investigate the effect of serum gonadotropin and total testosterone levels on semen parameters. Materials and Methods: Three hundred and eighty-two patients that applied to a male infertility polyclinic were included in our study. Serum gonadotropin and total testosterone levels and semen parameters of the patients were analyzed during the first visit to the clinic. The reference FSH value was 1.5-12.4 mIU/mL, that of LH was 1.7-8.6 mIU/mL and the reference value for total testosterone was 249-836 ng/dL. Results: While there was no statistically significant difference between the patients with low gonadotropin levels and the controls regarding any of the semen parameters (p > 0.05), there was a strong statistically significant difference between the patients with high gonadotropin levels and the controls regarding sperm concentration (p = 0.000), total motility (p = 0.000), progressive motility (p = 0.000), and morphology (p = 0.000). There was a strong statistically significant difference between the patients with low testosterone levels and the controls regarding total motility (p = 0.012) and progressive motility (p = 0.010), and a weak statistically significant difference in morphology (p = 0.042). There was no statistically significant difference in semen volume or sperm concentration (p > 0.05). There was no statistically significant difference in any of the semen parameters between the patients with high testosterone levels and the controls (p > 0.05). Conclusions: Our findings especially regarding LH and T levels are not in agreement with previous reports. In this regard, there is a need for larger-scale and randomized trials to resolve this discrepancy.


2021 ◽  
Vol 12 ◽  
Author(s):  
Muhammad Nabeel Shahid ◽  
Tahir Mehmood Khan ◽  
Chin Fen Neoh ◽  
Qi Ying Lean ◽  
Allah Bukhsh ◽  
...  

Background. Infertility is an emerging health issue for men. Comparative efficacy of different pharmacological interventions on male infertility is not clear. The aim of this review is to investigate the efficacy of various pharmacological interventions among men with idiopathic male infertility. All randomized control trials evaluating the effectuality of interventions on male infertility were included for network meta-analysis (NMA) from inception to 31 April 2020, systematically performed using STATA through the random effect model. The protocol was registered at PROSPERO (CRD42020152891).Results. The outcomes of interest were semen and hormonal parameters. Treatment effects (p < 0.05) were estimated through WMD at the confidence interval of 95%. Upon applying exclusion criteria, n=28 RCTs were found eligible for NMA. Results from NMA indicated that consumption of supplements increases sperm concentration levels [6.26, 95% CI 3.32, 9.21] in comparison to SERMs [4.97, 95% CI 1.61, 8.32], hormones [4.14, 95% CI 1.83, 6.46], and vitamins [0.15, 95% CI −20.86, 21.15)] with placebo, whereas the use of SERMs increased percentage sperm motility [6.69, 95% CI 2.38, 10.99] in comparison to supplements [6.46, 95% CI 2.57, 10.06], hormones [3.47, 95% CI 0.40, 6.54], and vitamins [−1.24, 95% CI −11.84, 9.43] with placebo. Consumption of hormones increased the sperm morphology [3.71, 95% CI, 1.34, 6.07] in contrast to supplements [2.22, 95% CI 0.12, 4.55], SERMs [2.21, 95% CI −0.78, 5.20], and vitamins [0.51, 95% CI −3.60, 4.62] with placebo. Supplements boosted the total testosterone levels [2.70, 95% CI 1.34, 4.07] in comparison to SERMs [1.83, 95% CI 1.16, 2.50], hormones [0.40, 95% CI −0.49, 1.29], and vitamins [−0.70, 95% CI −6.71, 5.31] with placebo. SERMs increase the serum FSH levels [3.63, 95% CI 1.48, 5.79] better than hormones [1.29, 95% CI −0.79, 3.36], vitamins [0.03, 95% CI −2.69, 2.76], and supplements [−4.45, 95% CI −7.15, −1.76] in comparison with placebo.Conclusion. This review establishes that all interventions had a significantly positive effect on male infertility. Statistically significant increased sperm parameters were noted in combinations of zinc sulfate (220 mg BID), clomiphene citrate (50 mg BID), and testosterone undecanoate and CoQ10; tamoxifen citrate and FSH were shown to improve the hormonal profile in infertile males.


2016 ◽  
Vol 46 (4) ◽  
pp. 433-438 ◽  
Author(s):  
Douglas da Cruz MATTOS ◽  
Rafaela SCRENCI-RIBEIRO ◽  
Leonardo Demier CARDOSO ◽  
Manuel Vazquez Vidal JUNIOR

ABSTRACT The blue discus (Symphysodon aequifasciatus) is often sold for ornamental purposes. It is a neotropical cichlid from South America, which is native to the rivers of the Amazon basin of Brazil, Peru and Colombia. The purpose of this study was to characterize the reproductive behavior of S. aequifasciatus and identify features that can later be used by breeders to facilitate the handling and reproduction of this species in captivity. The experiment was divided into two stages: the first dealt with partner selection and couple formation to observe the behaviors of territoriality, pursuing, fleeing, biting, stay, protecting and cleaning of the substrate. The second stage documented mating behavior, nesting and parental care, to observe vibration, spawning, permanence with the offspring, aeration of eggs, cleaning of spawning, color change and shift-taking in parental care. The results of the study allowed identifying disputes for and establishment of territory, as well as the selection and cleaning of the substrate for spawning performed by both sexes. The parental care was observed from spawning in the substrate until the care for the larvae. It was found that the reproductive success of this species is closely linked to biparental care observed during the entire reproductive process and early stages of the hatchings.


2018 ◽  
Vol 10 (1) ◽  
pp. 117-129
Author(s):  
Chongxun Mo ◽  
Guiyan Mo ◽  
Junkai Qin ◽  
Ming Zhou ◽  
Qing Yang ◽  
...  

Abstract This paper examines the rainfall and runoff characteristics in a karstic basin of China. The results indicated that the inner-annual distributions of rainfall and runoff were uneven and slightly different, as the concentration period of rainfall (from April to October) was earlier; there was a delay of about a month before the runoff (from May to September), and the concentrated volume accounted for 87% of annual precipitation or annual streamflow. Interannually, rainfall changed more significantly than runoff, the wet years lasted longer than the dry years (rainfall), while the high and low flow years were equal for runoff. In addition, judging from the value of the Mann-Kendall test, the average annual change of rainfall (−2.36) was more significant than that of runoff (−2.05), and the seasonal pattern of runoff maintained an opposite tendency in autumn and winter before 1990. The changes in runoff were mainly associated with rainfall and the formation conditions in the karstic area, and the reservoir in this basin should be operated with different flood limiting water levels, and the vegetation coverage should be improved.


1998 ◽  
Vol 25 (5) ◽  
pp. 864-879 ◽  
Author(s):  
Jean Morin ◽  
Michel Leclerc

Lake Saint-François is a relatively shallow fluvial lake of the St. Lawrence River with numerous deep channels. This complex system has been considerably altered from its pristine state 150 years ago. Currently, the water level is stabilized and the flow is regulated; important areas have been dredged and the major part of its outflow is diverted through the Beauharnois canal. The evolution of water levels shows a trend towards stabilization as required for ship traffic in the St. Lawrence Seaway and for hydropower production. With the construction of the Moses-Saunders dam in 1960, the flow of the river could be regulated; changes occur in the seasonal pattern of the flow. Ancient stage-discharge relationships were recreated to describe the impact of the 1849 damming and of the present level stabilization. Stabilization of the water level has favored the growth of submerged plants. Manning's friction coefficient was used to show that plant biomass has doubled since 1920; the onset of biomass increases corresponds to a water level stabilization event. The distribution of wetlands in the Lake Saint-François area was drastically modified by the water level rise caused by the 1849 damming. New wetlands were created and pre-1849 wetlands, located on what are currently shoals in the central part of the lake, have totally disappeared.Key words: Lake Saint-François, St. Lawrence River, impact of civil works, flow discharge regulation, water level regulation, wetland flooding cycle, submerged macrophyte, ecosystem reaction, civil work history.


1981 ◽  
Vol 59 (10) ◽  
pp. 1916-1920 ◽  
Author(s):  
Deborah H. Harding ◽  
Josefine C. Rauch

Body weights of free-ranging and captive juvenile Richardson's ground squirrels (Spermophilus richardsoni) were determined at regular intervals during the nonhibernating season. Animals in captivity gained weight at a faster rate and to a greater extent than those in their natural habitat. Attainment of maximum weights in captive ground squirrels was associated with a reduction in food intake and could not be related to food availability, a change in temperature, or in photoperiod.


2010 ◽  
Vol 114 (10) ◽  
pp. 2160-2181 ◽  
Author(s):  
Joecila Santos da Silva ◽  
Stephane Calmant ◽  
Frederique Seyler ◽  
Otto Corrêa Rotunno Filho ◽  
Gerard Cochonneau ◽  
...  

2004 ◽  
Vol 16 (2) ◽  
pp. 267
Author(s):  
A. Mahmoud ◽  
B. Kouakou ◽  
E. Amoah ◽  
S. Gelaye

Seasonal variation of the reproductive activity of small ruminants in the southern USA is controlled by photoperiod. We tested the hypothesis that artificial manipulation of photoperiod has an effect on caprine testicular activity and semen quality. The objective of this study was thus to determine the effects of photoperiod on caprine scrotal circumference and semen parameters during the nonbreeding season. Ten Saanen and Alpine bucks, two to three years old, raised at the Small Ruminant Research and Extension Center of Fort Valley State University (latitude 32°37′ N, longitude 83°39′ W), were used in the study. Throughout the study, the bucks were fed a concentrate diet containing 16% crude protein, and 2.7 Mcal/Kg of digestible energy. Two groups of bucks randomly selected were exposed to long daylight (16L:8D; n=5) or ambient daylight (12L:12D, control;; n=5) for a period of three weeks during the month of March. Scrotal circumference measurements and semen collection were conducted on each buck twice a week for a total of five trials. Semen samples were collected using an artificial vagina and an electroejaculator. Samples were immediately transferred to the laboratory for further evaluation. Data were analyzed as a completely randomized design with repeated measures using SAS program (SAS, 1990). When means were significant by ANOVA (P<0.05), they were separated by least significant difference. Results are presented as the least square means±SEM. Long daylight did not affect semen volume (mL), % motility, sperm concentration (billions/mL), % viability, or % abnormality(P>0.05). However, semen motility, sperm concentration, and abnormality were influenced by treatment in trials 3, 1, and 5, respectively (P<0.05). The least square means±SEM values for these parameters were 35±15, 0.58±0.1, and 20.0±3.7 for long daylight-treated bucks v. 87±15, 0.13±0.1, and 7.8±3.7 for the control, respectively. Further, long daylight affected scrotal circumference (P<0.05). Scrotal circumferences were decreased in trials 1, 2, and 5 (P<0.05). Long daylight decreased scrotal circumference without affecting semen quality in this study.


Author(s):  
Jan Kuper

The life-history and behaviour of the chironomid Metriocnemus (Inermipupa) carmencitabertarum was studied for three years and a comparison was made between two populations in the Netherlands. Key life-history characteristics are reported, including the number of generations (2-5 generations) and duration of larval development (19-55 days). Life-history characteristics differed between the two populations and between generations within a population. These differences were likely related to differences in competitors (mainly Chironomus riparius Meigen) and thermal characteristics of the habitat from variations in water volume and ambient temperature. Results suggested a diapause in summer, when water levels dropped, and not in winter. A clear seasonal pattern in body size was found with pupal length increasing steeply at the beginning of the summer. The increase in body size was positively correlated with mean ambient temperature during larval development. This correlation is in contrast with the Temperature-Size Rule (TSR) in ectotherms, which postulates a negative correlation between temperature and adult body size. The chance of ectotherm predators being present in the habitat is low, which may explain this feature. Life history characteristics supported a recent northward range expansionfor M. (I.) carmencitabertarum due to warmer winters. If correct, it is predicted that the species will be found in Scotland and northern Germany and/or southern Denmark in the near future.


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