Using ultrasonography method for monitoring ovarian status in freshwater stingray (Potamotrygon sp.)

ABSTRACT A simple and quantitative procedure for the extraction and measurement of total urinary radioactive steroid metabolites is described. The urinary excretion of topically applied 14C oestrone + 3H 17β-oestradiol and of 14C cortisol (11β, 17, 21-trihydroxy-pregn-4-ene-3, 20-dione) alone was studied with and without the addition of carrier oestrone, in both premenopausal and postmenopausal women. Over 80 percent of the cortisol, 7.5 to 41 percent of the oestrone, and 3.4 to 20 percent of the 17β-oestradiol metabolites appeared in the urine within 72 hours. Neither the ovarian status of the subjects nor the presence of carrier oestrone appeared to influence these results.

Download Full-text

Pendrin immunoreactivity in the gill epithelium of a euryhaline elasmobranch

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00178.2002 ◽

2002 ◽

Vol 283 (4) ◽

pp. R983-R992 ◽

Cited By ~ 51

Author(s):

Peter M. Piermarini ◽

Jill W. Verlander ◽

Ines E. Royaux ◽

David H. Evans

Keyword(s):

Collecting Duct ◽

Apical Region ◽

Intercalated Cells ◽

Cortical Collecting Duct ◽

Gill Epithelium ◽

Dasyatis Sabina ◽

Proton Atpase ◽

Atlantic Stingray ◽

Freshwater Stingray ◽

Gill Lamellae

Pendrin is an anion exchanger in the cortical collecting duct of the mammalian nephron that appears to mediate apical Cl−/HCO[Formula: see text]exchange in bicarbonate-secreting intercalated cells. The goals of this study were to determine 1) if pendrin immunoreactivity was present in the gills of a euryhaline elasmobranch (Atlantic stingray, Dasyatis sabina), and 2) if branchial pendrin immunoreactivity was influenced by environmental salinity. Immunoblots detected pendrin immunoreactivity in Atlantic stingray gills; pendrin immunoreactivity was greatest in freshwater stingrays compared with freshwater stingrays acclimated to seawater (seawater acclimated) and marine stingrays. Using immunohistochemistry, pendrin-positive cells were detected on both gill lamellae and interlamellar regions of freshwater stingrays but were more restricted to interlamellar regions in seawater-acclimated and marine stingray gills. Pendrin immunolabeling in freshwater stingray gills was more apical, discrete, and intense compared with seawater-acclimated and marine stingrays. Regardless of salinity, pendrin immunoreactivity occurred on the apical region of cells rich with basolateral vacuolar-proton-ATPase, and not in Na+-K+-ATPase-rich cells. We suggest that a pendrin-like transporter may contribute to apical Cl−/HCO[Formula: see text] exchange in gills of Atlantic stingrays from both freshwater and marine environments.

Download Full-text

Live Weight Changes and Their Relationship with the Ovarian Status of Maiden Fat-Tailed Barbarine Ewes

Journal of Agricultural and Marine Sciences [JAMS] ◽

10.24200/jams.vol15iss0pp41-46 ◽

2010 ◽

Vol 15 ◽

pp. 41

Author(s):

Imēne Ben Salem ◽

Mourad Rekik ◽

Mohammed Ben Hamouda ◽

Narjess Lassoued

Keyword(s):

Weight Loss ◽

Reproductive Performance ◽

Ovarian Function ◽

Live Weight ◽

Weight Changes ◽

Ewe Lambs ◽

Ovarian Status ◽

Weight Variation ◽

Igf I ◽

Semi Arid

The current study assessed the effect of the pattern of live weight change on the ovarian function of maiden Barbarine ewes at approximately 1 year of age. For this purpose, a total of 171 weaned ewe lambs (mean live weight ± s.d. 34.7±3.07 kg and mean age ± SD 196±10 days at weaning) were selected for the experiment. Adjustment of live weight variation was used. Based on the slope of the curve, animals were grouped into three classes LWCI (n=46), LWCII (n=91) and LWCIII (n=34) with live weight loss being highest in LWCI and lowest in LWCIII. Following laparoscopy at 13 months of age, the proportion of ewe lambs found cycling in LWCIII (85.3%) was higher in comparison to animals in LWCI (43.4%; P<0.001) and tended to be superior to those in LWCII (61.5%; P<0.05). Following synchronisation with progestagen of the females found cycling, levels of plasma IGF-I concentrations between 6 and 42 hrs after removal of sponges were not significantly different between the three classes of live weight, and respectively averaged 94.2, 90.8 and 89.8 µg/l for LWCI, LWCII and LWCIII females. Levels of estradiol were also not significantly different between the three groups (0.73, 0.70 and 0.67 pg/ml for LWCI, LWCII and LWCIII ewe lambs, respectively). It was concluded that, in low input systems of semi-arid and arid Tunisia, mating ewe lambs at the approximate age of 1 year is likely to lead to depressed reproductive performance particularly when the summer live weight-loss is elevated.

Download Full-text

Melatonin deprival modifies follicular and corpus luteal growth dynamics in a sheep model

Reproduction ◽

10.1530/rep-13-0405 ◽

2014 ◽

Vol 147 (6) ◽

pp. 885-895 ◽

Cited By ~ 14

Author(s):

Maria Elena Manca ◽

Maria Lucia Manunta ◽

Antonio Spezzigu ◽

Laura Torres-Rovira ◽

Antonio Gonzalez-Bulnes ◽

...

Keyword(s):

Antioxidant Properties ◽

Growth Dynamics ◽

Oestrous Cycle ◽

Trolox Equivalent Antioxidant Capacity ◽

Corpora Lutea ◽

Sheep Model ◽

Ovarian Status ◽

Trolox Equivalent ◽

And Function ◽

Breeding Seasons

This study assessed the effect of melatonin deprival on ovarian status and function in sheep. Experimental procedures were carried out within two consecutive breeding seasons. Animals were divided into two groups: pinealectomised (n=6) and sham-operated (n=6). The completeness of the pineal gland removal was confirmed by the plasma concentration of melatonin. Ovarian status was monitored by ovarian ultrasonography for 1 year to study reproductive seasonality. Follicular and corpus luteal growth dynamics were assessed during an induced oestrous cycle. As the effects of melatonin on the ovary may also be mediated by its antioxidant properties, plasma Trolox equivalent antioxidant capacity (TEAC) was determined monthly for 1 year. Pinealectomy significantly extended the breeding season (310±24.7 vs 217.5±24.7 days in controls;P<0.05). Both pinealectomised and sham-operated ewes showed a well-defined wave-like pattern of follicle dynamics; however, melatonin deficiency caused fewer waves during the oestrous cycle (4.3±0.2 vs 5.2±0.2;P<0.05), because waves were 1 day longer when compared with the controls (7.2±0.3 vs 6.1±0.3;P<0.05). The mean area of the corpora lutea (105.4±5.9 vs 65.4±5.9 mm2;P<0.05) and plasma progesterone levels (7.1±0.7 vs 4.9±0.6 ng/ml;P<0.05) were significantly higher in sham-operated ewes compared with pinealectomised ewes. In addition, TEAC values were significantly lower in pinealectomised ewes compared with control ones. These data suggest that melatonin, besides exerting its well-known role in the synchronisation of seasonal reproductive fluctuations, influences the growth pattern of the follicles and the steroidogenic capacity of the corpus luteum.Free Italian abstractAn Italian translation of this abstract is freely available athttp://www.reproduction-online.org/content/147/6/885/suppl/DC1.

Download Full-text