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The mammary glands of 30 non-pregnant, intact ewes were developed by subcutaneously injecting oestrogen plus progesterone at intervals of 3 days from day 0 to day 27. Two days later (day 29), 15 ewes were injected subcutaneously with 18 mg ergocryptine, to inhibit specifically secretion of prolactin. Then groups of ewes, each comprising five ergocryptiine-treated and five untreated ewes, were injected from days 30 to 34 with either four intravenous injections each day of 1 i.u. syntocinon, one subcutaneous injection each day of 10 mg dexamethasone trimethylacetate, or two subcutaneous injections each day of 2-5 mg oestradiol benzoate plus 6-25 mg progesterone. All ewes were milked by hand on days 30-50. Within 24 h of injecting ergocryptine, levels of prolactin in serum were reduced to negligible values (less than 2 ng/ml). Comparison of results for ewes not receiving ergocryptine showed that syntocinon, dexamethasone and oestradiol benzoate plus progesterone, at the doses used, were equally effective in initiating milk secretion. Peak yields of 0-23-0-27 kg/day were achieved. On the other hand, ewes treated with ergocryptine before syntocinon or dexamethasone produced peak yields of only 0-12-0-13 kg/day and ewes treated with ergocryptine before oestradiol benzoate plus progesterone produced negligible amounts of secretion. The results suggest that syntocinon and dexamethasone were either lactogenic per se or effected the release of hormones of the lactogenic complex other than prolactin. However, oestradiol benzoate plus progesterone appeared to be lactogenic by virtue of the influence of oestrogen on the secretion of prolactin.

Responses to exogenous growth hormone were measured in lactating dairy cows surgically prepared to allow measurement of nutrient exchanges across mammary and hind-limb muscle tissues. Cows were injected daily with either saline or growth hormone, at a dose of 0.1 mg/kg liveweight, over periods of 6 days. During administration of growth hormone milk yield, milk fat content and yields of milk fat protein and lactose increased. Arterial plasma concentrations of glucose and non-esterified fatty acids were increased, uptake of glucose by leg muscle tissue decreased, lactate release from leg muscle tended to increase, mammary uptake of non-esterified fatty acids increased, blood flow to leg muscle tended to increase and blood flow to mammary tissue increased during injection of growth hormone. The results show that growth hormone affects supply to and utilization of key nutrients by tissues, resulting in the supply to the mammary gland of additional precursors for milk synthesis.

Responses of broiler chickens to a high ambient temperature (35 degrees C) were measured in two experiments. In one experiment temperatures were increased abruptly from 21 degrees C to a daily range of 21-35 degrees C whereas, in the other, temperatures were increased more gradually over 6 days. The high temperatures were maintained for 5 h/day. In both experiments, birds exposed to the high temperatures ate less food and gained less liveweight than birds maintained at 21 degrees C. Efficiency of food conversion to liveweight gain and body composition were not affected by high temperature but there was a tendency for thyroid weight to decrease. Overall, the plasma concentration of triiodothyronine (T3) decreased and the plasma concentration of thyroxine (T4) increased, resulting in a decreased T3/T4 molar ratio, during exposure to high temperature. The concentration of plasma growth hormone, but not plasma reverse T3, was increased by high temperature. The initial responses to increased temperature were variable, with birds exposed more gradually adjusting relatively well until the maximum temperature was increased to 35 degrees C. All heated birds readjusted quickly to the daily reduction in temperature to 21 degrees C.

A 26-year experience with all aspects of priapism is reviewed in 105 children and adults. The etiology of the priapism was idiopathic or drug-induced, or owing to sickle cell disease, trauma, neoplasia, leukemia, papaverine-phentolamine injections and total parenteral alimentation. The pathophysiology of prolonged erection is discussed. Treatment is reviewed in respect to initial studies before the type of shunting procedure required is selected. Various shunt techniques are presented with outcome. Complications and their possible causes are discussed, and the importance of medicolegal risk is emphasized. Impotence is a common sequela of priapism.

A review of the complications of urethral instrumentation performed at our institution during the last 15 years revealed 2 cases of urethrorectal perforation. These patients were managed with loop colostomy and suprapubic cystostomy diversion with excellent healing and no evidence of fistula formation at 24-month followup. This rare complication is described and the principles of diagnosis, prevention and prompt aggressive management are emphasized.

The experiment comprised two sections. First, radiotracer techniques were used to study the metabolism of IgG1 and IgG2 in 5 non-pregnant and 4 pregnant ewes. In the pregnant ewes, the rates of synthesis for IgG1 and IgG2 were similar to the rates observed in non-pregnant animals. However, the irreversible loss of IgG1 was significantly greater than IgG2 in pregnant ewes and IgG1 in non-pregnant ewes. Additionally, it was found that most of the IgG1 and virtually all of the IgG2 in mammary secretion was serum derived. Secondly, the levels of sodium, potassium and lactose and the selective index for IgG1 in mammary secretions of 5 pregnant ewes were monitored over the parturient period. The values of all the measures remained relatively constant until one day before parturition. From one day pre-partum, the levels of potassium and lactose in mammary secretion began to increase and had risen 2-3 fold by 5 days post-partum. Over the same period, the selective index for IgG1 decreased 20 fold, wehreas the level of sodium fell from approximately 32 mmol/l to 18 mmol/l. The concentration of IgG1 in plasma slowly declined from approximately 23 g/l to 15 g/l over the last 10 days of pregnancy. During the parturient period, the decline in plasma IgG1 levels, in comparison with IgG2, without alteration in the rates of synthesis of either immunoglobulin, supports the hypothesis that selective transport of IgG1 into mammary secretion occurs without degradation. The results also indicate that the transport of sodium and potassium into mammary secretions are altered over the parturient period.

Ewes which had been lactating for 3--4 weeks and which had been milked by hand from the day of parturition were subjected to food restriction for 4 days. One group of three ewes was fed ad libitum and a second group of four ewes was fed to meet calculated requirements for maintenance and milk production. Over 4 days food intake was reduced by 80% in both groups of ewes. In response to food restriction, milk yields and body weight decreased. Blood amino acids, plasma glucose, glucose pool size, glucose irreversible loss, insulin, thyroxine and the insulin: glucagon molar ratio decreased. In contrast, plasma glucagon remained relatively unaffected and plasma free fatty acids and growth hormone increased. These changes were similar for both groups of ewes and were reversed when food intake was restored. The results suggest that the hormonal control of gluconeogenesis in the ruminant is similar to that in the non-ruminant.

Within the experimental design of this study, the following conclusions were drawn: A unilateral vertical dislodging force applied to a distal-extension removable partial denture is transmitted to the supporting structures with a vertical and horizontal component. The presence of indirect retainers transmits the vertical component of force to both indirect retainer abutment teeth while the horizontal component is transmitted to the indirect retainer and primary abutments on the side opposite the loading force. The presence of indirect retainers reduces the stress to the primary abutment teeth. The presence of indirect retainers distributes stress to more supporting teeth.

Responses to daily injections of bovine growth hormone (GH, 0.15 mg kg-1 liveweight), beginning on day 10 of lactation, were measured in lactating ewes. Milk yields of GH-treated ewes increased soon after commencement of injections and continued to increase for some 25 days before reaching plateau levels. By comparison, yields of ewes injected with excipient (controls) decreased over the experiment. There was a tendency for contents of milk fat to be higher and milk protein to be lower for GH-treated than for control ewes during the first 15-20 days after injections were started. At the beginning and over the first 15-20 days of the experiment feed intakes of both groups of ewes were similar, but thereafter intakes of GH-treated ewes gradually increased to reach plateau levels some 200-300 g day-1 higher than for control ewes by about day 35. Liveweights of both groups of ewes decreased during the first 2 weeks of treatment then increased, with GH-treated ewes losing, then gaining, more weight than control ewes. The efficiency of food utilization for milk production was higher for GH-treated than control ewes throughout the experiment but digestibility of food organic matter was not different during the eighth week of the experiment. At the end of the experiment, body composition, assessed by dilution of tritiated water, was similar for both groups of ewes. Differences in milk production were not sustained after withdrawal of GH injections. Measurements of tissue uptake of key metabolites were made on days 3 and 45 of GH treatment. On day 3, GH lowered uptake of glucose and non-esterified fatty acids by leg muscle tissue and increased mammary uptake of non-esterified fatty acids. By day 45 there were no apparent differences of tissue uptake of key metabolites. The results indicate that there is a biphasic response to exogenous GH in the lactating ruminant. It appears that initially GH affects nutrient partition thereby increasing supplies to the mammary gland of key nutrients for milk synthesis. In the longer term, GH increases feed intake, which provides sufficient nutrients to sustain increased milk production and also liveweight gain.

Lactating ewes received continuous intravenous infusions of adrenaline (0.05 micrograms/kg liveweight) for 4 days. Prior to, during and after adrenaline infusions, milk yield and composition were monitored. Plasma concentrations of metabolites and hormones were measured each day and glucose biokinetics were measured in non-steady state at the start and end of adrenaline infusions. During adrenaline infusion, milk yield and content of solids-not-fat decreased and milk fat content was reduced on the first day of infusion. Plasma glucose was raised throughout the period of adrenaline infusion, plasma lactate increased over the first 4 h from the start of infusion and plasma non-esterified fatty acids increased for 2 h at the start of infusion and tended to increase during the first 2-3 h after withdrawal of adrenaline. Plasma growth hormone remained relatively stable except for a marked increase at 30 min after withdrawal of adrenaline. At the start and immediately after withdrawal of adrenaline infusion plasma insulin was increased approximately twofold. Glucose production, but not utilization, increased at the start of infusions. Immediately after withdrawal of adrenaline glucose utilization increased 2.5-fold with a smaller response in glucose production. There was essentially no change in glucose clearance during adrenaline infusion but a marked increase occurred after withdrawal of adrenaline.

Injections of an anlogue of prostaglandin F2alpha (T.F.101) initiated secretion of copious amounts of fluid resembling normal ovine milk when given to non-pregnant ewes with developed mammary glands. Injections of T.F.101 elicited a substantial but transient increase in the levels of prolactin in plasma. Results for intact and ovariectomized ewes were similar.

Adriamycin used in combination with vitamin E (Tocopherol) was evaluated in the treatment of Nb rat prostate adenocarcinoma. Vitamin E has been shown to enhance the growth-inhibitory effects of adriamycin on human prostatic carcinoma cells in vitro. The adriamycin-vitamin E treatment groups had the lowest average final tumor volume, but the mortality rate was 57% (17/30). These results suggest that vitamin E may play a role in enhancing the cytotoxic effects of adriamycin, but may not have any protective effect on normal cells as previously suggested through in vitro methods.

Two separate experiments were conducted with alloxan-induced, diabetic ewes. In one study it was found that the diabetes induced by alloxan could be stabilized with exogenous insulin (1.2-1.3 U h-1). Feed intake and milk yield were maintained at normal levels even though a mild hyperglycaemia persisted. Despite this, milk fat content tended to increase, an observation that is consistent with insulin being a key factor in the aetiology of the low-milk-fat syndrome in the ruminant. Interruption of insulin infusion then resumption at 90% of the rate previously required to stabilize the diabetes was followed by marked changes in glucose kinetics. Initially, glucose production increased with little change in glucose utilization. This resulted in an increase in plasma glucose, which remained high even though both glucose production and utilization increased, to be similar on resumption of insulin infusions. It seems that the changed sensitivity to insulin reflects 'up-regulation' of insulin receptors. In a second study, exogenous recombinant bovine growth hormone (rebGH) was administered to insulin-stabilized, diabetic ewes. Immediately after the first injection of rebGH, glucose production increased with little change in glucose utilization, which led to increased plasma glucose. This observation suggests that rebGH was glucogenic. Ultimately, it was necessary to increase the dose of insulin to stabilize plasma glucose and by the fourth day of injection of rebGH, the insulin infusion rate required to stabilize the ewes had doubled from c. 1.5 to c. 3 U h-1. After cessation of injections of rebGH the dose of insulin required to stabilize the ewes decreased. These observations confirm the diabetogenic activity of growth hormone (GH) in the sheep.

Penile necrosis is a rare entity but it may be brought about more readily if certain risk factors are present. Such factors are discussed in this paper and the reader is forewarned about this problem.

Selective transfer of IgG1 into milk and levels of sodium and potassium in milk of lactating ewes were followed before and after intramammary infusion of colchicine or alpha-haemolysin. Milk production decreased substantially following infusions and the ionic composition of milk changed such that levels of sodium increased and of potassium decreased. By 3-4 days after infusions milk production had increased to approach pre-infusion levels and levels of sodium and potassium had returned to pre-infusion values. Selective transfer of IgG1 into milk was enhanced following inhibition of milk production but decreased following the acute inflammation induced by alpha-haemolysin. The results of these experiments are consistent with the view that, in the ruminant, selective transfer of IgG1 into mammary secretion is inversely related to the synthetic activity of the alveolar epithelium. Associated with enhanced selective transfer of IgG1, substantial changes occur in the ionic composition of milk. Moreover, acute inflammation of the mammary gland impairs selective transfer of IgG1 into milk, but during recovery from inflammation selective transfer of IgG1, is enhanced. The latter phenomenon may be functionally significant for recovery from intramammary infection.

Changes in production parameters and metabolite biokinetics induced by treatment with pituitary-derived bovine growth hormone (bGH) were monitored at peak (c. 40 days) and mid-lactation (c. 130 days) in dairy cows. During treatment with bGH milk production increased by 6 and 14% at peak and mid-lactation respectively. At peak lactation the content of milk fat tended to increase, whereas milk protein tended to decrease and milk lactose decreased significantly. Yield of milk fat increased, but there was no change in the yield of milk protein and lactose. The content of milk fat tended to increase at mid-lactation. Milk protein decreased and there was no change in milk lactose. Yields of milk fat and lactose but not protein increased. Growth hormone exerted metabolic effects which differed with stage of lactation. At peak lactation plasma glucose concentration and its irreversible loss increased, plasma urea and acetate were unchanged and their irreversible losses tended to increase. No change was measured for plasma non-esterified fatty acids (NEFA) and the irreversible loss of NEFA decreased. At mid-lactation plasma concentrations of glucose and NEFA were increased, plasma urea decreased and acetate and 3-hydroxybutyrate tended to increase. Irreversible losses of NEFA increased, urea tended to decrease and acetate and glucose remained essentially constant. The results show that exogenous pituitary bGH exerts metabolic effects which result in the supply of increased nutrients to support milk synthesis. The metabolic effects differ with the stage of lactation, reflecting differences in physiological and/or nutritional state.

Diuretic renography frequently is used to assess obstruction in hydronephrosis of infancy but it is invalidated by poor renal function, which occurs frequently in this age group. In an attempt to establish a guideline to determine when renal function is too poor in infancy to rely on diuretic renography for an accurate diagnosis we analyzed the slope of the diuretic renographic washout curve of the normal, nonaffected kidney in 33 infants with unilateral hydronephrosis. When the T 1/2 time in the normal, nonaffected kidney was greater than 9 minutes, as occurred in 68 per cent of the infants less than 1 month old, it defined a significant renal functional impairment in both kidneys that interfered with diuretic renographic test interpretation. With time renal function improved and after 4 months of age the T 1/2 time in all nonaffected kidneys became normal and the diuretic renographic diagnosis of obstruction became accurate. Our study indicates that nonaffected kidney T 1/2 time provides a qualitative assessment of global renal function in infancy and defines a level of renal functional maturity that must be achieved to ensure diuretic renographic test accuracy.

Urinary diversion utilizing a continence-maintaining ileal valve has been performed in 12 canines. This procedure offers a simple surgical procedure and uses the diversion's internal fluid pressure to maintain continence. Of 12 canines with this continence-maintaining ileal valve, 11 remained continent at sacrifice. Operative complications were minimal and late complications occurred in 2 dogs. Histological evaluation of the diversionary tissues revealed slight changes in the mucosa of the ileal valve, with some flattening of the villi. This procedure may have a clinical role in urinary diversion for patients with pelvic malignancy or patients who need urinary diversion for other reasons.

An antiserum to purified bovine C-peptide was used to develop a sensitive radioimmunoassay for C-peptide in sheep. The assay was used to measure kinetics of C-peptide and insulin in non-pregnant and non-lactating sheep. Injected, purified C-peptide was distributed in pools comprising c. 11.4% of liveweight, the half time of C-peptide was estimated as 13.7 min and its clearance rate was c. 5 ml kg-1 min-1. In lactating ewes exogenous recombinant bovine growth hormone (rebGH) increased both plasma insulin and C-peptide as did glucose challenge given before and during administration of rebGH. Estimates of insulin secretion rate in lactating ewes were c. 7 x 10(-3) and 8.5 x 10(-3) nmol kg-1 min-1 before and after glucose challenge prior to injections of rebGH. After 4 days of injection of rebGH, corresponding values were c. 8 x 10(-3) and 10 x 10(-3) nmol min-1 kg-1.

Two separate experiments were conducted to examine the effects of exogenous oestrogen on selectivetransfer of IgG1 into mammary secretion of ewes. In one experiment, non-pregnant ewes were induced to lactate artificially by first developing mammary glands with injections of progesterone plus low doses of oestrogen then triggering milk secretion with either glucocorticoid or high doses of oestrogen. In the other experiment, lactating ewes were injected with oestrogen each day for 6 days. The results of the experiments suggest that oestrogen affects selective transfer of IgG1 into mammary secretion of the ewes. Moreover, the results show that, in the absence of high levels of oestrogen in blood, the magnitude of the selective transfer of IgG1 into mammary secretion is related inversely to the synthetic activity of the glandular epithelium.

After intravenous administration of alloxan (50 mg kg-1 liveweight) to lactating ewes, there were triphasic changes in plasma glucose and insulin. Almost immediately, plasma insulin decreased and hyperglycaemia occurred, then, between c. 5-12 h, insulin increased and ewes became hypoglycaemic. Thereafter, insulin decreased and glucose increased from c. 20 h after alloxan and the diabetic state was established. Changes in glucose production and utilization correlated with changes in plasma glucose. Exogenous insulin was administered from 30 h after alloxan, and it took some 2 weeks to stabilize ewes. During this period, when mild hyperglycaemia persisted, milk yields and feed intakes were decreased but milk fat content was elevated. Once ewes were stabilized, plasma glucose, milk yield, feed intake and milk fat content returned to levels prior to alloxan. These observations are consistent with insulin playing a role in the aetiology of the 'low milk fat syndrome' in the ruminant. It appears that the alloxan-treated, insulin-stabilized ewe would be a useful model for studying the role of insulin during lactation, but it is necessary to allow time for animals to overcome effects of administration of alloxan.

Injections of dexamethasone trimethylacetate initiated lactation in nulliparous Ayrshire heifers previously given a series of injections of oestradiol benzoate plus progesterone to develop mammary glands. Essentially normal lactation occurred following injection of 20 mg/day dexamethasone for 3 days, whereas injection of 40 mg/day for 4 days initiated secretion of smaller volumes of milk-like fluid containing relatively high levels of lipid. Milking alone failed to initiate lactation.

Exogenous bovine growth hormone at a dose of 0.1 mg kg-1 liveweight increased yields of milk and milk constituents and milk fat content when injected over 5 days into ewes in mid-lactation. These changes in milk production were associated with changes in the supply to, and utilization of, nutrients by leg muscle and mammary tissues. Arterial concentrations of glucose and non-esterified fatty acids increased significantly, concentrations of lactate and 3-hydroxybutyrate tended to increase, and concentrations of triglycerides associated with very low-density lipoproteins decreased significantly. Growth hormone increased mammary uptake of non-esterified fatty acids, decreased mammary uptake of very low-density lipoproteins and tended to reduce the release of lactate from leg muscle. Oxidation of non-esterified fatty acids in the whole body and mammary tissue was increased by growth hormone and there was a tendency for reduction of glucose oxidation in mammary tissues. During injection of growth hormone, blood flow to leg muscle and mammary tissues increased as did the calculated ratio of blood flow; milk yield. These changes in blood flow, together with changes in arterial concentrations and tissue utilizations of key metabolites, were sufficient to account for the synthesis of extra milk and milk constituents.

Lactating goats and sheep were fitted with catheters in the external pudendal arteries supplying both mammary glands. Saline was infused continuously into one artery whereas the other artery received continuous infusions, over successive 4-day periods, of either saline or growth hormone (GH)-doses increasing twofold between successive periods from 100 to 400 micrograms/day in goats and 400 to 3200 micrograms/day in sheep. Local infusion of GH at up to 1600 micrograms/day in sheep did not affect milk yield or composition nor peripheral plasma concentrations of GH, insulin, glucose, urea and non-esterified fatty acids (NEFA). Infusion of GH at 3200 micrograms/day in sheep increased peripheral plasma concentrations of GH, tended to increase milk yield and peripheral plasma NEFA but there were no changes in peripheral plasma insulin, glucose and urea. It is concluded that GH does not exert direct effects on the mammary glands of sheep and goats in situations where the hormone is administered over short periods.

An attempt has been made to evaluate the importance of prolactin and 'progesterone withdrawal' for lactogenesis. The experimental model system used was the ovariectomized, non-pregnant ewe induced to lactate artifically by treatment with trigger hormone (either oestrogen, glucocorticoid or oxytocin) alone or in combination with progesterone. It appears from the results that prolactin is important in the lactogenic responses elicited by oestrogen and oxytocin but not as important in the response elicited by glucocorticoid. Moreover, the results suggest that, in the ewe, an appropriate positive hormonal stimulus will overcome the inhibitory influence of progesterone on lactogenesis.