Retire Our Excess Grain Capacity?

Now, more than ever, agriculture can outproduce market demand. It looks as though some things will stay this way for some time. Agriculture is faced with a problem of output management or supply control, just as are some nonfarm industries. (See Output Management for Agriculture? in the April issue or reprint FS-910.

GONADOTROPHINS AND TESTOSTERONE IN THE XYY SYNDROME

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32715/1/0000082.pd

Seminal fluid sperm concentrations

Biweekly seminal fluid sperm concentrations from one individual over a period of 120 weeks. During this period the individual received no medication and reported no periods of febrile illness. Dotted line indicates 20 million/ml which is generally considered to be the lower limit of normal range

Stimulation of sperm production by human luteinizing hormone in gonadotropin-suppressed normal men

The relative roles of FSH and LH in the control of human spermatogenesis are not well established. We previously reported that supraphysiological doses of hCG can stimulate sperm production in gonadotropin-suppressed normal men despite prepubertal FSH levels. To determine whether more nearly physiological levels of human LH (hLH) also can stimulate spermatogenesis when FSH levels are suppressed, we administered hLH to normal men whose endogenous gonadotropin levels and sperm production were suppressed by exogenous testosterone enanthate (T). After a 3-month control period, 11 normal men received 200 mg T, im, weekly to suppress LH and FSH. T administration alone was continued for 3-4 months until 3 successive sperm concentrations (performed twice monthly) revealed azoospermia or severe oligospermia (sperm concentrations, less than 4 million/ml). Then, while continuing T, 4 of the 11 men (experimental subjects) simultaneously received 1100 IU hLH, sc, daily for 4-6 months to replace LH activity, leaving FSH activity suppressed. The effect on sperm production of the selective FSH deficiency produced by hLH plus T administration was determined. The remaining 7 men (control subjects) continued to receive T alone at the same dosage, without gonadotropin replacement, for an additional 6 months. In the four experimental subjects, sperm concentrations increased significantly from 0.7 +/- 0.7 million/ml (mean +/- SEM) during T treatment alone to 19 +/- 4 million/ml during hLH plus T administration (P less than 0.001). However, none of the men achieved sperm concentrations consistently in their own pretreatment range. Sperm motilities and morphologies were normal in all four subjects by the end of hLH plus T administration. In contrast, sperm concentrations in the seven control subjects remained suppressed (less than 3 million/ml) throughout the entire period of prolonged T administration alone. Serum LH bioactivity, determined monthly by in vitro mouse Leydig cell bioassay in all four experimental subjects, was markedly suppressed during T administration alone (120 +/- 10 ng/ml) compared to that during the control period (390 +/- 20 ng/ml; P less than 0.001). With the addition of hLH to T, LH bioactivity returned to control levels (400 +/- 40 ng/ml; P = NS compared to control value). Serum FSH levels determined monthly by RIA were reduced from 98 +/- 12 ng/ml during the control period to undetectable levels (less than 25 ng/ml) during the T alone and the hLH plus T periods (P less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS

Elevated serum follicle-stimulating hormone levels in men with normal seminal fluid analyses

Three men who volunteered as normal subjects were found to have abnormally high levels of serum follicle-stimulating hormone (FSH) despite having normal seminal fluid analyses and fertility. Two of the men had a history of previous orchitis, and one had an atrophic testis. Serum luteinizing hormone and testosterone levels were normal. These cases appear to represent compensated primary testicular disease, with normal sperm counts and fertility maintained at the expense of chronically elevated FSH levels. These results imply that in certain situations, the measurement of serum FSH levels may be a more sensitive index of testicular disease than the performance of seminal fluid analyses