Production, behaviour and fertility of Merino wethers, hemi-castrates with reduced testicular parenchyma and induced cryptorchids

Greasy wool production, body weight, behaviour and fertility of male, fine wool Merino sheep were studied from 10 to 21 months of age to assess their suitability for wool production. The males were either castrated (wethers), or were hemi-castrated with a vasectomy and reduction (either partially or in full) of the parenchyma of the retained testicle, or the testicles pushed up into the ingulnal canal and the scrotum shortened (induced cryptorchids). There were significant differences among all groups in body weight, with increases being associated with the larger amounts of testicular tissue present. Fertility was low in the induced cryptorchids at 19 months of age. The hemi-castrates with reduced testicular parenchyma were infertile. The hemi-castrates with reduced testicular parenchyma had significantly heavier greasy fleece weights than the wethers and induced cryptorchids, which had similar fleece weights. The wether group suffered a higher prevalence of posthitis in spring and autumn than the hemi-castrate or induced cryptorchid groups. Those hemi-castrates with the largest amount of testicular parenchyma retained and the induced cryptorchids exhibited masculine behaviour patterns and had an increased incidence of fly strike to the head. The principle of hemi-castration and reduction of the testicular parenchyma is shown to be applicable in wool producing flocks with the potential to increase greasy wool production while minimising the management and marketing limitations previously associated with induced cryptorchids.     

Frictional melting during the rupture of the 1994 bolivian earthquake

The source parameters of the 1994 Bolivian earthquake (magnitude Mw = 8.3) suggest that the maximum seismic efficiency eta was 0.036 and the minimum frictional stress was 550 bars. Thus, the source process was dissipative, which is consistent with the observed slow rupture speed, only 20% of the local S-wave velocity. The amount of nonradiated energy produced during the Bolivian rupture was comparable to, or larger than, the thermal energy of the 1980 Mount St. Helens eruption and was sufficient to have melted a layer as thick as 31 centimeters. Once rupture was initiated, melting could occur, which reduces friction and promotes fault slip.     

Ileal impaction in 22 cows

The clinical signs, diagnosis, treatment and outcome of 22 cows with ileal impaction were investigated using the medical records of bovine patients referred to the Department of Farm Animals, Vetsuisse Faculty, University of Zurich from 1993 to 2003. Only 15 of the cows had signs of colic, which were subtle but slowly increased in severity in some patients. The results of haematological and biochemical analyses were mildly abnormal in only few animals. There was no correlation between the duration of the disorder before admission, the severity of symptoms and the results of the haematological and biochemical analyses. Dilated loops of small intestine in the right dorsal quadrant of the abdomen could be palpated transrectally and imaged via ultrasonography. A definitive diagnosis of ileal impaction was made during exploratory laparotomy by finding the impaction and ruling out other abnormalities. In 19 cows, the obstructing food mass was easily massaged into the caecum, and in three animals an enterotomy was carried out. All cows had an uneventful recovery with no recurrence of the disorder. It is concluded that the cause of the impaction was most likely due to seasonal influences and winter-feeding with a hay based ration. The short and long-term prognosis after surgical intervention was good.     

Mandibular fractures in cattle--treatment and results

The results of a retrospective investigation of 25 cases of mandibular fractures in cattle are reported; 19 animals were treated and 6 slaughtered without therapy. Five cases of unilateral fracture of the pars molaris healed with conservative therapy, whereas the same method of treatment was unsuccessful in four cases with compound fractures (2 x pars incisiva, 1 x diastema, 1 x pars molaris) and in one with multiple fractures of the corpus and ramus of the mandible. For animals with symphyseal fractures, surgical fixation using cerclage wire (three cases) proved successful, as did percutaneous fixation in six animals with fractures of the diastema or body of the mandible. The fractures healed well in 14 out of 19 treated cattle and the animals were retained, on average, for a further four years.     

Effects of pH, sodium bicarbonate, cryoprotectants and foetal bovine serum on the cryopreservation of European eel sperm.

The main objective of the present study was to evaluate the influence of pH and bicarbonate concentration in the activation or inhibition of European eel (Anguilla anguilla) spermatozoa and to evaluate the effect of different cryoprotectants: dimethyl sulphoxide (DMSO), acetamide, ethylene glycol, propanol, glycerol and methanol (MeOH). The effect of these factors was evaluated comparing the percentage of motile cells, the percentage of alive cells (by Hoechst staining) and the spermatozoa morphometry pre- and post-cryopreservation (by computer-assisted morphology analysis). Based on the above findings, three cryoprotectants (DMSO, MeOH and glycerol) were chosen and evaluated in two media (P1 and P1 modified) with different concentrations of NaHCO(3) and in the presence or absence of foetal bovine serum (FBS). The effect of these factors was evaluated comparing the percentage of alive and motile cells post-cryopreservation. DMSO was the cryoprotectant showing better results in relation to the percentage of spermatic alive cells post-freezing and caused a smaller modification of the head spermatozoa morphology. The combination of P1-modified medium with DMSO and containing FBS increased slightly but significantly the percentage of motile spermatozoa post-cryopreservation.