Production levels and health status in Iberian piglets at weaning.

The aim of this study was to describe the postweaning growth of Iberian piglets and its relationship with the occurrence of diarrhea. To assess these factors in response to different weaning ages, a total of 360 pure-breed Iberian piglets were studied. Three trials were conducted with 120 piglets from 24 litters randomly assigned to be weaned at 28 or 42 d of age (12 litters and 60 piglets each). In each trial and from each weaning age, 4 groups of 15 piglets were assembled with different sexes and sizes (3 litters by group and 5 animals from each litter; 12 replicates and 180 piglets/weaning age). The duration of study period was 42 d and all animals were weighed weekly from 21 to 63 d of age. Food intake and fecal consistency were examined with the same frequency. General linear models and chi-square procedure was used with SPSS statistical package to perform the analysis with a confidence interval of 95% (P < 0.005). Pearson and Spearman analyses were conducted to examine relationships between variables. At the beginning (P = 0.798) and end of the study (P = 0.450) there were no significant differences between piglet weights. After weaning, there were differences in food intake and in conversion rates (P < 0.001), but there were no differences in ADG for the whole study period (P = 0.335). All groups experienced a similar decline in production rates during the first week after weaning and similar recovery times during the next weeks. Both weaning groups had a similar overall prevalence (P = 0.044) and incidence of diarrheal onset (P = 0.467), and regression analysis showed relationships between postweaning diarrhea and the overall prevalence of piglets before weaning (P < 0.01) and food intake during first week postweaning (P < 0.01). Therefore, weaning age has a similar influence on postweaning growth and on postweaning diarrhea in Iberian piglets.

Improvement of semen quality in infected asymptomatic infertile male after bacteriological cure.

Bacteriological etiology was investigated in 29 infected asymptomatic infertile males. The localization of the infection and the effect of a long term antibiotic therapy on semen parameters were evaluated. The most frequent etiological agent isolated was Enterococcus faecalis. Positive bacteriological culture was obtained in prostatic fluid in 16 patients and in semen in 13. Bacteriological cure was achieved in 24 cases and it was associated with improved seminal parameters: sperm concentration, viability and total motile sperm per ejaculate. In 5 patients without bacteriological cure there was no change in semen analysis after antibiotic therapy. In 45% of the infected patients there were less than 0.5 x 10(6)/ml seminal polymorphonuclear leukocytes. In view of these findings granulocyte concentration seems to be a poor marker to predict infection.

Glucocorticoids: their role on gonadal function and LH secretion.

The aim of the study was to investigate gonadal function and LH reserve in patients on chronic therapy with supraphysiological doses of GC. We clinically evaluated 17 male subjects (aged 23-56 years-old) on chronic GC therapy. In four subjects (aged 23-39 years-old) randomly selected, three basal blood samples were drawn and pooled for measurement of SHBG, total, free and bioavailable testosterone. Following baseline samples, a GnRH stimulation test was performed. Starting with a priming of 5 micrograms, a bolus of 50 micrograms of GnRH was injected intravenously and samples obtained every 30 minutes for assessment of LH. Four healthy men (aged 24-28 years-old) were used as controls. Patients on steroids referred decreased libido (58%) and impotence (52%) and lower back pain (41%). Total, free and bioavailable serum testosterone were significantly lower than controls (p < 0.01, p < 0.05 and p < 0.05, respectively) while SHBG levels persisted unchanged. Baseline LH and its rise after GnRH was normal. This study shows that chronic GC administration involves gonadal function reducing sexual steroids without changes in baseline and stimulated LH secretion. In addition, the priming with physiological doses of GnRH optimizes the pituitary response to higher GnRH doses.

Seminal plasma modulates lymphokine-activated killer cell activity in vitro.

We have previously reported that seminal plasma (SP) pool from donors and azoospermic patients can inhibit the NK response in vitro. In this study we investigated whether SP also inhibits the interleukin -2-activated natural cytotoxicity (LAK). Pools of SP from 10 healthy donors and 17 azoospermic patients were used. They were sterilized by filtration and stored at -20 degrees C until use. Anti-sperm antibodies were negative in all samples. Peripheral blood lymphocytes (PBL) obtained from volunteer donors were incubated during 16 hours in culture medium, RPMI alone, with 10% fetal calf serum (FCS) or with 10% human serum (HuS). The NK and LAK cytotoxicity assay was performed using the cell line K 562 labeled with 51Cr. In view of our results, we conclude that LAK activity is inhibited by SP when PBL are incubated in the absence of FCS. This inhibitory effect of SP is unrelated to cellular death and there is no difference between healthy and azoospermic seminal plasma.

Biosynthesis of testicular steroids in the immature, adult and senescent guinea-pig.

The potential biosynthetic capacity of testicular hormones was studied in immature, pubertal and aging guinea-pig. In their sexual development towards puberty, changes in the relationship of the steroids involved in the steroidogenic pathways were observed. The testosterone/androstenedione ratio changes markedly, showing an important increase with pubertal proximity. The testosterone in equilibrium androstenedione sequence, reversibly catalyzed by 17 beta-hydroxysteroid oxidoreductase (17 beta-oxido-reductase), clearly shifted towards androstenedione in immature animals irrespective of the precursor utilized. Post-pubertal animals showed a greater enzymatic activity in the 5-ene and 4-ene testicular synthesis pathways, testosterone production being greatest. In the aging animal, hormonal biosynthetic capacity falls. Reversion of the 17 beta-oxido-reductase activity could be one of the mechanisms responsible for the decrease in testosterone, as in immature guinea-pigs. In order to investigate the in vitro steroidogenic capacity of glands at different ages, minces of testicular tissue were incubated with labelled precursors. The studies were conducted in triplicate at 35 degrees C. For equal quantities of incubated tissue the non-metabolized amount of [3H]pregnenolone and [14C]progesterone, utilized as precursors, was different in post-pubertal and senescent animals: 55.7 +/- 3 vs 59.3 +/- 2.3% (P less than 0.01) for pregnenolone, and 50.1 +/- 3.3 vs 56.3 +/- 2.9% (P less than 0.01) for progesterone, respectively. Testosterone production was 12 +/- 2% in adult and 6.7 +/- 2.7% in senescent animals (P less than 0.01). The testosterone/androstenedione ratio was not significantly different in post-pubertal and senescent animals: 2.8 +/- 0.5 vs 2.4 +/- 0.4, but consistently higher than found in immature animals: 0.3 +/- 0.1. The lesser potential capacity of the aging tissue to synthesize testosterone could be explained by a decline in the glands capacity to metabolize the hormonal precursors.

Immunologic studies of male infertility.

The immunological basis of male sterility, as previously described, is related to alterations of spermatogenesis or impairment of seminal plasma formation. Both may be developed independently or may be related. Acute or subacute lesions of the genital tract or gonads may be more closely related to the presence of autosensitization than are chronic inflammatory processes or endocrine diseases of the testis. Oligo- or azoospermia may reflect the destruction of cells or halting of spermatogenesis. Immobilization and agglutination of sperm cells would depend predominantly on an allergic reaction that originates in the adnexal glands. Antibodies against testis do not affect adnexal glands but may immobilize epididymal spermatozoa, whereas antiseminal plasma antibodies react only with adnexal glands and seminal spermatozoa, but not with testicular cells. The pathogenic role of detectable antispermatic antibodies in sterile male or female patients are not sufficiently clarified. Their presence apparently correlate with unexplained cases of infertility, but this does not necessarily mean that they are specifically responsible for this abnormality; furthermore, they might be only an epiphenomenon of the immunological process involved.

Alpha-interferon induces cortisol release by human adrenals in vitro.

It is at present not clear whether alpha interferon (INF-alpha) can participate in the control of glucocorticoid blood levels through direct action on the adrenal gland. In this study, the possible action of INF-alpha on cortisol release by adrenal tissue was tested in vitro. Slices of normal human adrenals were incubated with INF-alpha for 3 h at 37 degrees C in 95% air and 5% CO2. Cortisol release by adrenal tissue was stimulated by INF-alpha, showing a dose-response curve from 20 IU/ml, the lowest dose that gave a response, to a maximal dose of 60 IU/ml when the response reached a plateau. The effect of INF-alpha on cortisol liberation by adrenal tissue in vitro may be implied in neuroimmune regulatory interactions.

Eclampsia inducida por aloinjertos de piel en ratas espontáneamente hipertensas / Eclampsia induced by skin allografts in spontaneously hypertensive rats

Se intentió desarrolar un modelo experimental en eclampsia para estudiar su posible etiologia. Veinitdós ratas hembras de la cepa endocriada espontáneamente hipertensa (SHR) fueron injertadas con piel de machos de la cepa Holtzman. Se realizaron 4 injertos con intervalos de diez días. Cada SHR fue apareado con el macho donante correspondiente diez días después del último injerto. Como controles use usaron cinco SHR apareados con machos Holtzman si injertos previos. En la mayoría de las ratas experimentales que quedaron preñadas se encontraron alteraciones que consistieron en: bajo número de crías, fetos muertos, abortos y retardo dei crescimiento. La función renal fue evaluada antes y durante la preñez, mostrando un aumento fisiológico del filtrado glomerular del 7,5%, mientras que en la preñez normal se encotró un incremento del 166%. La histología renal mostró lesiones compatibles con coagulación intra-ratas puede afectar el normal desarrollo de la preñez y sugieren que podrían verse involucrados factores inmunológicos en el desarrollo de eclampsia (AU)

Eclampsia inducida por aloinjertos de piel en ratas espontáneamente hipertensas / Eclampsia induced by skin allografts in spontaneously hypertensive rats

Se intentió desarrolar un modelo experimental en eclampsia para estudiar su posible etiologia. Veinitdós ratas hembras de la cepa endocriada espontáneamente hipertensa (SHR) fueron injertadas con piel de machos de la cepa Holtzman. Se realizaron 4 injertos con intervalos de diez días. Cada SHR fue apareado con el macho donante correspondiente diez días después del último injerto. Como controles use usaron cinco SHR apareados con machos Holtzman si injertos previos. En la mayoría de las ratas experimentales que quedaron preñadas se encontraron alteraciones que consistieron en: bajo número de crías, fetos muertos, abortos y retardo dei crescimiento. La función renal fue evaluada antes y durante la preñez, mostrando un aumento fisiológico del filtrado glomerular del 7,5%, mientras que en la preñez normal se encotró un incremento del 166%. La histología renal mostró lesiones compatibles con coagulación intra-ratas puede afectar el normal desarrollo de la preñez y sugieren que podrían verse involucrados factores inmunológicos en el desarrollo de eclampsia

[Eclampsia induced by skin allografts in spontaneously hypertensive rats]. / Eclampsia inducida por aloinjertos de piel en ratas espontáneamente hipertensas.

In order to develop an experimental model for eclampsia, 22 female inbred Spontaneously Hypertensive Rats (SHR) were grafted with skin from Holtzman males. The implantation of four sequential grafts took place at an interval of ten days. Each SHR was mated with its corresponding skin donor ten days after the last graft. Five non grafted SHR mated with Holtzman males were used as controls. In most of the experimental rats that became pregnant we found changes which consisted in: low number of offspring, stillborn fetuses, abortions and growth delay. Renal function was evaluated before and during pregnancy showing a physiological increase in glomerular filtration of 7.5% (basal = 0.93 +/- 0.12 ml/min, peak = 1.00 +/- 0.12 ml/min) as compared with an increase of 166% (basal = 0.68 +/- 0.22 ml/min, peak = 1.85 +/- 0.33 ml/min) in the control group. Renal histology showed lesions corresponding to disseminated intravascular coagulation. These results indicate that the association of skin grafts and hypertension in these rats affects the normal development of pregnancy and suggest that immunological factors could be involved in experimental eclampsia.

Eclampsia inducida por aloinjertos de piel en ratas espontáneamente hipertensas. / [Eclampsia induced by skin allografts in spontaneously hypertensive rats]

In order to develop an experimental model for eclampsia, 22 female inbred Spontaneously Hypertensive Rats (SHR) were grafted with skin from Holtzman males. The implantation of four sequential grafts took place at an interval of ten days. Each SHR was mated with its corresponding skin donor ten days after the last graft. Five non grafted SHR mated with Holtzman males were used as controls. In most of the experimental rats that became pregnant we found changes which consisted in: low number of offspring, stillborn fetuses, abortions and growth delay. Renal function was evaluated before and during pregnancy showing a physiological increase in glomerular filtration of 7.5

(basal = 0.93 +/- 0.12 ml/min, peak = 1.00 +/- 0.12 ml/min) as compared with an increase of 166

(basal = 0.68 +/- 0.22 ml/min, peak = 1.85 +/- 0.33 ml/min) in the control group. Renal histology showed lesions corresponding to disseminated intravascular coagulation. These results indicate that the association of skin grafts and hypertension in these rats affects the normal development of pregnancy and suggest that immunological factors could be involved in experimental eclampsia.

Cushing's syndrome and autoimmunity.

Is Cushing's syndrome ever caused by adrenal stimulating autoantibodies? Specific antiadrenal antibodies were found in the serum of three of seven patients with Cushing's syndrome. The immunologic techniques that showed positive results were complement fixation, tanned RBC hemagglutination, and immunofluorescence. Lymphocytic infiltration of the adrenal was present in two cases, in one of which nodular hyperplasia seemed to be of primary adrenal origin with autoimmunity as a possible cause. However, in cases with clear-cut pituitary origin, the lymphocytic adrenalitis and circulating adrenal antibodies are likely secondary to antigen leaking from damaged tissue.