Testicular and epididymal sperm content in grazing Cashmere bucks: seasonal variation and prediction from measurements in vivo

1994 ◽  
Vol 6 (6) ◽  
pp. 727 ◽  
Author(s):  
SW Walkden-Brown ◽  
BJ Restall ◽  
WA Taylor
Keyword(s):  
Seasonal Variation ◽  
Seasonal Pattern ◽  
Sperm Production ◽  
Epididymal Sperm ◽  
Scrotal Circumference ◽  
Indirect Measures ◽  
Significant Seasonal Variation ◽  
Testicular Weight ◽  
Daily Sperm Production

Each month, for 15 months, the testes and epididymides were recovered from five Australian cashmere bucks selected at random from a group of mature bucks (initial n = 116) at pasture (location 29 degrees S, 153 degrees E). The extent of seasonal change in testicular and epididymal sperm reserves was determined and indirect methods for predicting these reserves were developed. Paired testicular weight exhibited clear seasonal variation from 137 g in August to 269 g in February. The total elongated spermatid content of the testes, determined by homogenization, showed a very similar seasonal pattern, ranging from 13.8 x 10(9) in September to 36.2 x 10(9) in March. Seasonal changes of similar timing were observed for paired epididymal weight and sperm content. Although changes in total testicular spermatid content were largely the result of change in testicular weight (R2 = 0.72, P < 0.001), the elongated spermatid content of testicular parenchyma (mean, 127 x 10(6) g-1) exhibited significant seasonal variation with elevated values between February and June, suggestive of an increase in the efficiency of spermatogenesis. Daily sperm production, calculated by means of a spermatogenic time divisor for sheep, ranged from 2.76 x 10(9) in September to 7.23 x 10(9) in February. Scrotal circumference, scrotal volume and testicular length x diameter2 were identified as accurate predictors of testicular weight (R2 > or = 0.87) and sperm content (R2 > or = 0.70). The results demonstrate that: (a) cashmere bucks exhibit considerable seasonal variation in spermatogenesis associated primarily with changes in testicular mass but also with changes in the efficiency of spermatogenesis; and (b) indirect measures of testicular size are good predictors of testicular elongated sperm content. When the correct spermatogenic time divisor for goats is determined, such indirect measures may be used to predict daily sperm production.

scholarly journals Mucormycosis in the Eastern Mediterranean: a seasonal disease

2005 ◽  
Vol 134 (2) ◽  
pp. 341-346 ◽  
Author(s):  
M. R. AL-AJAM ◽  
A. R. BIZRI ◽  
J. MOKHBAT ◽  
J. WEEDON ◽  
L. LUTWICK
Keyword(s):  
Seasonal Variation ◽  
Fungal Infection ◽  
Pulmonary Infection ◽  
Pattern Analysis ◽  
Eastern Mediterranean ◽  
Seasonal Pattern ◽  
Atmospheric Concentration ◽  
Tel Aviv ◽  
Significant Seasonal Variation ◽  
Immunocompromised Hosts

Mucormycosis is a fairly rare fungal infection caused by ubiquitous fungi of the order Mucorales and primarily affects immunocompromised hosts. A series of 16 cases of invasive mucormycosis admitted to three referral centres in Beirut, Lebanon between 1981 and 1999 is described. It includes 12 patients with rhinocerebral, three with cutaneous, and one with pulmonary infection. Onset of symptoms occurred in the summer and autumn in 15 out of 16 patients, showing a statistically significant seasonal variation (P=0·007) A recent report of 19 patients from Tel Aviv describes a strikingly similar seasonal pattern. Studies on atmospheric concentration of Mucorales spores in the Eastern Mediterranean are lacking. Weather pattern analysis in Beirut revealed clustering of onset of invasive mucormycosis at the end of a dry, warm period, which begins around May and ends in October. Mucormycosis incidence appears to be seasonal in the Eastern Mediterranean.

scholarly journals Seasonal Variation and Global Public Interest in the Internet Searches for Osteoporosis

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Chao Wang ◽  
Xiong Shu ◽  
Jianfeng Tao ◽  
Yanzhuo Zhang ◽  
Yue Yuan ◽  
...  
Keyword(s):  
Seasonal Variation ◽  
Public Interest ◽  
Seasonal Pattern ◽  
Late Winter ◽  
Search Term ◽  
Ibandronic Acid ◽  
Search Volume ◽  
Significant Seasonal Variation ◽  
Relative Search Volume ◽  
Google Search

Background. To ascertain the seasonal pattern and global public interest in osteoporosis by evaluating search term popularity changes of the disease over a decade. Methods. We applied Google Trends to retrieve search popularity scores for the term “osteoporosis” between January 01, 2004, and December 31, 2019. Cosinor analyses were conducted to examine the seasonality of osteoporosis, and analysis on osteoporosis-related topics including hot topics and rising-related topics was also performed. Results. The cosinor analyses demonstrated a statistically significant seasonal variation in relative search volume of the “osteoporosis” in the world ( p = 0.0083 ), USA ( p < 0.001 ), UK ( p < 0.001 ), Canada ( p < 0.001 ), Ireland ( p < 0.001 ), Australia ( p < 0.001 ), and New Zealand ( p < 0.001 ), with a peak in the late winter months and trough in the summer months. The peaks in late winter and valley in summer presented an approximately 6-month difference between hemispheres. The top 11 rising topics were denosumab, FRAX, hypocalcaemia, zoledronic acid, ibandronic acid, osteomyelitis, osteopenia, osteoarthritis, bone, calcium, and bone density. Conclusions. Google search query volumes related to osteoporosis follow strong seasonal patterns with late winter peaks and summer troughs. Further studies aimed at elucidating the possible mechanisms behind seasonality in osteoporosis are needed. Moreover, Internet data including the top rising topics may alert physicians to strengthen the propaganda of osteoporosis timely, so as to further promote the development of public health interventions.

Prepubertal treatment of rats with clomiphene citrate affects postpubertal testicular development

1989 ◽  
Vol 120 (4) ◽  
pp. 423-428 ◽  
Author(s):  
Janine L. Brown ◽  
Prabir K. Chakraborty
Keyword(s):  
Cell Function ◽  
Clomiphene Citrate ◽  
Serum Testosterone ◽  
Normal Serum ◽  
Gnrh Receptor ◽  
Testicular Development ◽  
Fsh Receptor ◽  
Sperm Production ◽  
Testicular Weight ◽  
Daily Sperm Production

Abstract. A previous study showed that clomiphene citrate (clomiphene) reduced serum and pituitary gonadotropins and impaired testis growth and steroidogenesis in 10-day-old rats treated for up to two weeks. The present study was conducted to assess the effect of prepubertal clomiphene treatment on postpubertal pituitary-testicular function. Rats were implanted with pellets that released 0, 0.05, 0.5 or 5.0 mg clomiphene ·kg−1·day−1 between 10–31 days of age and were killed at 90 days of age. Testis and prostate weights in treated rats were reduced (P< 0.05), whereas serum LH, FSH and testosterone, and pituitary gonadotropin and GnRH receptor concentrations had recovered to levels observed in control rats. Testicular FSH receptor concentrations were not altered; however, FSH receptor content was decreased (P< 0.05) in clomiphene-treated rats proportional to the reduction in testicular weight. In contrast, testicular LH and GnRH receptor concentrations were increased (P< 0.05) in treated animals, resulting in similar receptor contents. Daily sperm production per gram of parenchyma was unaffected, while daily sperm production per testis was decreased in treated rats (P< 0.05). These data show early postnatal treatment with clomiphene does not permanently impair pituitary function. Despite reduced testicular mass, normal serum testosterone concentrations and testis LH receptor content of treated rats suggest recovered Leydig cell function. The decreased content of testicular FSH receptors and reduced sperm production suggest seminiferous tubule function was compromised in the adult rat.

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