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High incidence of goitre in human together with low level of iodine in water and cow milk have been observed in Southern Poland (Table I). Therefore, iodine deficiency was considered as the only cause of goiter development. The correlation coefficient between iodine concentration in water and cow milk was r = 0.76 (Fig. 1) and indicate the possibility of iodine determination in milk instead of water. The iodine determination in milk reflects the level of iodine in water as well as in food, a negative correlation has been obtained between goitre incidence in human and iodine concentration in water (r = 0.43) (Fig. 2.). A low correlation coefficient suggest that iodine is not a solely factor responsible for goitre development. Studies on cows have indicated that thiocyanate may have effect on goitre development as well. There has been found higher concentration of thiocyanate (SCN) in blood plasma and in enlarged thyroids (Table II). Thiocyanate belongs to goitrogenic compounds and its main source are the plants of Brassica species widely cultivated in southern Poland. It has been found that cows fed with Brassica plants have high level of SCN both in blood and milk with no alteration of plasma iodine level. The transfer of iodine from plasma to milk is only slightly affected (Table III). The level of SCN in the thyroid depends on its plasma concentration; the calculated correlation coefficient is r = 0.88 (Fig. 3). Enhanced thyrotropin (TSH) secretion (during goitrogenesis) may be accompanied by increased accumulation of SCN in the thyroid (like iodide) and reduced oxidation to SO4 (unlike iodide) (Fig. 4). Therefore we postulated that TSH may be partly responsible for increased SCN level in goitrous thyroids. The question arise whether increased ingestion of SCN does really potentiate iodine deficiency and goitrogenic process in animals breeding in southern Poland. For explanation some additionally experiments were performed on laboratory animals. It have been observed that enhanced level of plasma SCN following feeding with Brassica plants increased proportionally the goitrogenic action as well as the accumulation of 131J by the thyroid and its conversion into organic form (Fig. 5). The latter data was confirmed by positive correlation between thyroxine and plasma SCN levels in sheep (r = 0.49), (Fig. 6) Thiocyanate like other monovalent anions suppress goitrogenic effect of propylthiouracil. However, anti-goitrogenic properties of SCN depends on normal iodine ingestion (Fig. 7).(ABSTRACT TRUNCATED AT 400 WORDS)

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The effect of hydrocortisone and dexamethasone on superovulation was examined in 12 cows. On the day PMSG was given, each animal received either the first of five daily doses of 250 mg succinate hydrocortisone or one injection of 30 mg dexamethasone. In the 48-hr interval between the injection of PMSG and PGF(2)alpha, the concentration of progesterone rose from 6.97 to 10.22 ng/ml in the experimental groups and only to about 2.8 ng/ml in the control group. In the following days progesterone increased even more, from 15.7 to 26.0 ng/ml seven days after estrus in the experimental group and to 19.25 ng/ml in the control group. The group which received dexamethasone had an average of 4.7 corpora lutea and one embryo flushed per animal. The hydrocortisone group had an average of 2.5 corpora lutea and one cow had two embryos. The control group had 6.2 corpora lutea and 5.2 embryos per animal.

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The purpose of the present study was to examine the effect of arginine vasotocin (AVT) and mesotocin (MT) on the uterine contractility in the immature chicken treated with gonadal hormones. It was found that AVT and MT produced dose-dependent contraction of the chick uterine strips. In the control group the mean threshold doses were: AVT - 4.5 ng/ml, MT - 130 ng/ml. Pretreatment with progesterone (P) or testosterone (T) resulted in a considerable reduction of the contractile response to AVT. Oestradiol (E) and combinations: E + T and E + P + T increased the sensitivity of the uterus to AVT. Testosterone treatment supressed and combinations E + T and E + P + T enhanced the uterine response to MT. The obtained results could be summarized as follows: 1) AVT and MT cause uterine contraction in vitro in the immature hen: 2) AVT is much more potent than MT: 3) ovarian steroids change the sensitivity of the hen uterus to AVT and MT.

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Changes in blood vasotocin level in response to uterine stimulation in the hen. Acta Physiol. Pol. 1979, 30 (2): 267--272. The blood vasotocin level after uterine and vaginal stimulation was determined by bioassay, on the isolated frog bladder. It was found that uterine distension causes a 2--3 fold increase in the blood vasotocin level compared to that before distension. Vaginal distension was without any effect on the blood vasotocon level.

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The effect of 2 months fluoride administration (0.1 and 1.0 mg daily/rat) on thyroxine and triiodothyronine level in blood and T3-resin uptake ratio was investigated in rats. In addition, free thyroxine index was calculated from serum thyroxine level and T3-resin uptake ratio. It was found that fluoride administration caused: 1. decrease in thyroxine and triiodothyronine level in plasma; 2. decrease in free thyroxine index values; 3. Increase in T3-resin uptake ratio. From these observations as well as from previous experiments it was concluded that fluoride given continuously to the rats may influence the thyroid gland rather indirectly by changing thyroid hormone transportation in the blood.

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Measurements of hematocrit, total plasma protein and red cell volume were made during sexual excitement and copulation in boars. Red cell volume (RCV) was determined by isotope dilution technique using endogenous 51Cr-tagged red cells. Basing on these data changes in the total blood volume (TBV) and plasma volume (PV) were calculated by 2 indirect methods. RCV increased by 12% to 16% in the intial phase of ejaculation and remained increased during ejaculation and 40 minutes after copulation. TBV and PV decreased during copulation, greatest drop being found in the final phase of ejaculation. After ejaculation the TBV was increasing, first to the resting value before copulation (about 20 minutes after copulation), thereafter it became markedly higher than during the resting period. Depending on the method used for calculation significant differences were found in the quantity of TBV and PV drop during ejaculation.

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