Management of dairy heifers: Can operant conditioning be an effective and feasible tool to decrease stress and ease animals' close contact and handling?

Besides health monitoring, a regular check of dairy heifers' growth rate is desirable, but it is rarely done because procedures that require restraint and handling can be associated with substantial stress for both animals and farmers. Inexperienced heifers, especially if they are highly responsive to humans, may find restraint and handling potentially aversive. This study investigated whether training heifers of different age and responsiveness toward humans (RTH), through operant conditioning, could reduce stress in animals, ease close contact and handling, and be feasible in terms of farmers' effort. We assessed 60 Holstein heifers of 2 age classes (young, n = 29, 291 ± 39 d; old, n = 31, 346 ± 62 d) according to the avoidance distance test and classified them as confident (n = 20), neutral (n = 21), or nonconfident (n = 19). Half of the heifers of each age and RTH class were trained (n = 29), whereas the other half was not (n = 31). The trained heifers were subjected to target training for 8 sessions and positively reinforced with feed to allow being touched on the muzzle, rump, and perineum. If a heifer refused positive reinforcement, the trainer stepped back as negative reinforcement. In the last week of the experiment, the effect of training on the reaction to handling was assessed in all heifers. We measured heart rate, root mean square of successive interbeat interval differences (RMSSD), and fecal cortisol metabolites (FCMet). The presence of behavioral distress signs was recorded as well. The avoidance distance test was performed a second time 24 h after the measuring session. All of the trained heifers, regardless of RTH class, successfully accomplished the target training task in 6 sessions, each spending on average 25.3 s per session. All of the trained heifers allowed touches on the rump and perineum at the end of the fourth session. Training nonconfident heifers required more time compared with the others. Trained heifers showed higher RMSSD than nontrained heifers (14.2 vs. 16.9 ms, respectively), indicating a lower vagal tone, and thus, a slightly lower stress level than nontrained heifers. Training did not lead to differences in HR, FCMet, or presence of stress behavioral signs. Nonconfident heifers had the highest mean baseline FCMet values compared with neutral and confident heifers (38.4 vs. 30.3 vs. 29.1 ng/g, respectively). Nonconfident heifers also showed the lowest value of FCMet 12 h after the measuring session (36.7 vs. 44.6 vs. 49.7 ng/g), likely due to a decreased responsiveness of the adrenal gland to a stressor. The average avoidance distance decreased between the beginning and the end of the experiment, especially for neutral and nonconfident heifers, regardless of whether they were trained or not. These results show how using operant conditioning on some heifers not only decreased their vagal tone, but also reduced the responsiveness to humans of all the animals, trained and not trained; in the latter case, this reduction was through nonassociative learning, such as habituation.

Benefits and afterthoughts of laparoscopy for the nonpalpable testis.

PURPOSE: Recent reports in the literature indicate that laparoscopy tends to be seen as the most appropriate approach to the nonpalpable testis for diagnosis and therapy. The aim of our study was to evaluate the real benefits of laparoscopy in terms of diagnostic accuracy, safety, costs and validity of the chosen treatment. MATERIALS AND METHODS: We compared anatomical findings and results of the treatment of impalpable testes in 2 pediatric surgical groups, including 47 children treated laparoscopically during a 2 1/2-year period and 296 treated with open surgery (classic orchiopexy) in a 6 1/2-year period. RESULTS: There was no significant difference in the diagnosis of abdominal testes (51 versus 50%), whereas a difference was noted in inguinal (4 versus 15%) and absent testes (45 versus 35%). Differences in treatment were more striking. In the laparoscopic group standard orchiopexy was performed in 62.5% of cases versus 83% in the open group. Conversely the rate of Fowler-Stephens repairs increased from 5.5% of open surgery cases to 37.5% of laparoscopic cases. There have been no serious complications in the laparoscopic procedures. To date 6 of the 9 patients who underwent a staged Fowler-Stephens procedure have undergone complete repair (open second stage). A review of the literature revealed a similar but lower tendency to over perform the Fowler-Stephens operation in laparoscopic cases (34%) versus open surgery (8%). Also, in previous series there was a 29% orchiectomy rate during laparoscopy compared to only 5% in classic open surgery. In Italy under current public health programs overall costs of the laparoscopic approach to the nonpalpable testis become noncompetitive when the procedure is extended from only diagnostic to interventional use due to the need for additional trocars and other special instruments. In contrast, private health insurers provide an additional 30% for laparoscopic cases over the cost of open orchiopexy. CONCLUSIONS: Laparoscopy is definitively accurate in establishing the differential diagnosis of impalpable testis. The number of Fowler-Stephens repairs in the laparoscopic group seems inordinately high, probably due to a lack of definite standards in the proper assessment of the length of the internal spermatic vessel pedicle and the potential scrotal displacement of the testis. This reason may explain the higher number of orchiectomies reported in the literature.

Saralasin test as a diagnostic and prognostic aid in renovascular hypertensive patients subjected to renal operation.

A positive saralasin test in patients with angiographic evidence of renovascular disease and other positive functional tests gives further assurance that these patients will achieve normal or substantially reduced blood pressure postoperatively. In our experience with proved renovascular hypertension there was a 19 per cent incidence of falsely negative saralasin tests. Therefore, saralasin should not be used as the sole screening test in hypertensive patients suspected of having surgically correctable lesions. There is a direct correlation between elevated renin activity and a positive saralasin test. In some patients saralasin may be more sensitive than any other currently used test to detect overactivity of the renin-angiotensin system. This would determine those patients with technical errors in renin sampling and assays. Of the 16 patients (all normotensive) who had 6-month followup tests 5 had elevated peripheral renin activity, probably owing to furosemide stimulation. Of these 5 patients 2 had a positive postoperative saralasin test, raising the question of potential falsely positive responses in cases of essential hypertension and coincidental non-functional renal artery stenosis. Patients with high renin essential hypertension may respond to saralasin, even in the absence of renal artery lesions. A saralasin test should be done in a hospital where all specific conditions can be met and potential complications handled promptly.

Utricular configuration in hypospadias and intersex.

To evaluate the incidence and significance of an enlarged prostatic utricle in hypospadiac patients without underlying intersex 44 patients with the meatus located in the perineum, penoscrotal junction or proximal two-thirds of the penis were evaluated with cystourethroscopy immediately before the operation. There was an abnormally enlarged utricle in 57 per cent of the perineal, 10 per cent of the penoscrotal and none of the penile hypospadias and intersex revealed a high incidence of enlarged utricle or the presence of a vagina masculinus. Utricular enlargement in itself doses not indicate intersexuality but careful cystoscopic examination of its vault needs to be undertaken, searching for a cervix. An enlarged utricle can be a manifestation of delayed mullerian duct regression or decreased androgenic stimulation of the urogenital sinus.

Utricular configuration in hypospadias and intersex.

To evaluate the incidence and significance of an enlarged prostatic utricle in hypospadiac patients without underlying intersex 44 patients with the meatus located in the perineum, penoscrotal junction or proximal two-thirds of the penis were evaluated with cystourethroscopy immediately before the operation. There was an abnormally enlarged utricle in 57% of the perineal, 10% of the penoscrotal and none of penile hypospadiacs, for an over-all incidence of 14%. Concurrent analysis of a series of phenotypic male patients with hypospadias and intersex revealed a high incidence of enlarged utricle or the presence of a vagina masculinus. Utricular enlargement in itself does not indicate intersexuality but careful cystoscopic examination of its vault needs to be undertaken, searching for a cervix. An enlarged utricle can be a manifestation of delayed müllerian duct regression or decreased androgenic stimulation of the urogenital sinus.

Saralasin test as a diagnostic and prognostic aid in renovascular hypertensive patients subjected to renal operation.

A positive saralasin test in patients with angiographic evidence of renovascular disease and other positive functional tests gives further assurance that these patients will achieve normal or substantially reduced blood pressure postoperatively. In our experience with proved renovascular hypertension there was a 19% incidence of falsely negative saralasin tests. Therefore, saralasin should not be used as the sole screening test in hypertensive patients suspected of having surgically correctable lesions. There is a direct correlation between elevated renin activity and a positive saralasin test. In some patients saralasin may be more sensitive than any other currently used test to detect overactivity of the renin-angiotensin system. This would determine those patients with technical errors in renin sampling and assays. Of the 16 patients (all normotensive) who had 6-month followup tests 5 had elevated peripheral renin activity, probably owing to furosemide stimulation. Of these 5 patients 2 had a positive postoperative saralasin test, raising the question of potential falsely positive responses in cases of essential hypertension and coincidental non-functional renal artery stenosis. Patients with high renin essential hypertension may respond to saralasin, even in the absence of renal artery lesions. A saralasin test should be done in a hospital where all specific conditions can be met and potential complications handled promptly.

Minimal mortality of renal surgery.

Eight hundred fourteen renal operative procedures were reviewed to determine overall mortality and to identify patients at risk. The over-all mortality was 1.35%, but as high as 30% in patients with uremia and spesis. Carcinomatosis contributed to higher mortality in other groups. In the absence of these three factors renal surgery was associated with very low or no postoperative (thirty day) mortality.