The secretory pattern of luteinizing hormone (LH) and testosterone (T) and the temporal relationship between the two were studied in 4 mature rams (2-3 yr of age). Blood was obtained from the jugular by venipuncture at 20-min intervals for a 24 hr period from each of 2 crossbred rams in May and 2 Finnish Landrace rams in August and January. Serum levels of LH and T were determined in duplicate by RIA. LH estimations have been expressed in terms of ng NIH-LH-S14/ml. Rams sampled in May and August exhibited similar LH and T secretory patterns. Baseline levels of LH fluctuated from 0.20-0.94 ng/ml. During the 24-hr period each ram exhibited from 3-5 LH peaks averaging 9.59 ± 1.50 ng/ml and occurring at intervals of 6.9 ± 0.6 hr. Within 1 hr following each LH peak the blood T level consistently increased from baseline values of 0.30-1.53 ng/ml to peak values averaging 9.02 ± 1.53 ng/ml. The secretory pattern in January for the 2 Finnish Landrace rams differed considerably from that in August. For each ram 7 LH peaks were observed during the 24 hr, averaging 1.80 ± 0.55 ng/ml and occurring at intervals of 3.9 ±0.1 hr. LH releases were followed by increases in T which peaked at 19.66 ± 0.42 ng/ml within 40 min. We concluded that LH releases were occurring at random among the rams as elevations did not consistently occur at any particular hour. For each ram however, LH releases occurred at regular intervals and were always followed by sudden, dramatic increases in blood T. Under conditions of this study no consistent relationship was found to exist between the magnitude of the LH and resultant T peaks. (Endocrinology 95: 627, 1974).A PULSATILE secretion of luteinizing horjt\. mone (LH) and testosterone (T) has been observed in the male of a number of species. Assay of frequently collected serial blood samples from the human has revealed that both LH (1,2) and T (3,4,5) are secreted in spurts but there is no apparent cause and effect relationship between these two hormones. A pulsatile secretory pattern also exists for LH and T in the bull (6,7) and ram (8,9,10,11). Although LH releases are usually followed by increases of blood T levels in the bull, evidence to date suggests that this relationship does not occur in the ram (10,11).Results of previous studies involving determination of serum LH and T fluctuations in the ram have been obtained from hourly or less frequent blood samplings. However, the halflife of LH in the peripheral blood of sheep has been determined to be approximately 30 min (12). Therefore, in order to more accurately de-R3T 2N2.termine the secretory pattern of and the temporal relationship between LH and T in the ram we sampled 4 mature rams at 20-min intervals for 24-hr periods. Results indicate that a definite relationship exists between LH releases and sudden, dramatic increases in serum T and, add further support to the suggestion (9) that the secretory pattern for LH and T is altered from season to season in the ram.

Blood samples were collected monthly from captive and wild adult (12 months old or older) male white-tailed deer (Odocoileus virginianus) over 1 year in southwest Virginia. Plasma was assayed for luteinizing hormone (LH), follicle-stimulating hormone (FSH), prolactin (PRL), and testosterone (T) using radioimmunoassays. LH and T levels for the captive and wild deer were essentially similar and followed a distinct annual cycle. LH concentrations (nanograms per millilitre) peaked earlier (October, captive, 4.5 ± 1.8 (mean ± standard error); September, wild, 3.3 ± 0.9) than T concentrations (nanograms per millilitre) (November, captive, 13.3 ± 2.7; November, wild, 23.7 ± 7.8) and dropped off sharply prior to, or concomitant with, T concentrations. LH and T levels were lowest during the late winter and spring. T concentrations were closely correlated with androgen levels (Mirarchi, R. E., P. F. Scanlon, R. L. Kirkpatrick, and C. B. Schreck. J. Wildl. Manage. 41: 178–183 (1977)) determined by competitive protein binding assay. Mean PRL and FSH concentrations in wild and captive deer also displayed seasonal variations. Prolactin concentrations (nanograms per millilitre) were highest in May (147.5 ± 0.0) and lowest in November while FSH levels (nanograms per millilitre) peaked in September (180.2 ± 22.4) and were lowest in March. Differences in hormone concentrations between deer and sheep, and the relationship between PRL and antler growth and FSH and spermatozoan production, are discussed.

Eight adult Landrace boars were housed for 12 mo in one of two social environments. Socially nonrestricted boars were penned adjacent to and allowed minimal physical contact with ovariectomized gilts hormonally induced into estrus every 2 wk. Socially restricted boars were penned behind solid walls to eliminate visual and physical contact with other pigs. All animals were subjected to natural changes in daylength. Semen was collected weekly; gel-free volume, gel weight, sperm concentration and number per ejaculate, sperm motility (percent and type) and semen pH were determined. Total protein, citric acid contents and alkaline phosphatase activity were measured in seminal plasma. Testis length and width and various body temperature measurements were recorded monthly. Except for percent motile sperm and alkaline phosphatase activity, all semen characteristics varied (P less than .05) with month. The pattern of seasonal change in semen volume was modified by social environment (group X month, P less than .05). Sperm numbers were highest in winter and lowest in spring and summer. Ejaculate protein and citric acid contents were highest in fall and winter; decreases in spring were associated with moderate ambient temperatures and increases in daylength (r = -.80, P less than .05). Testicular length for socially nonrestricted boars was maximum in November through January and minimum in April through July, and did not vary as extensively for socially restricted boars. Scrotal temperature was elevated during periods of high ambient temperature, but not to values detrimental to spermatogenic function.(ABSTRACT TRUNCATED AT 250 WORDS)

Testosterone has been detected in whole human saliva. Levels averaged (+/- SE) 295 +/- 36 and 195 +/- 25 pg/ml in adult males and females, respectively, and usually were undetectable in children. In adult males, the excretion of testosterone in saliva appeared to follow a circadian rhythm.