Distribution of atrophy in the nasal ventral conchae of piglets infected experimentally with Bordetella bronchiseptica.

The distribution and extent of atrophy caused by Bordetella bronchiseptica in the nasal ventral conchae were investigated by intranasally infecting piglets at day 4 of life. Experimental and control piglets were killed at one, two, three, four, five and six weeks of age. Serial transverse 80 microns thick nondecalcified sections were cut throughout the entire length of the nasal ventral conchae, and microradiographed. It was observed that the distribution and extent of atrophy was not uniform along the ventral conchae. The articular and transverse laminae as well as the connecting zone were not atrophied, except at their rostral extremity. The entire dorsal scroll was atrophied. This atrophy was moderate, except at the rostral and caudal extremities of the dorsal scroll, where its size was less than half that of the controls. The ventral scroll was less atrophied than the dorsal scroll, although a marked atrophy was present at its rostral extremity. From these observations, it is suggested that two transverse sections should be made through the nose of pigs in order to establish a diagnosis of atrophic rhinitis at slaughter: one section at the level of the first-second premolar tooth and one more rostral section, at the level of the canine tooth.     

Transient stray voltage: Is it detrimental to growth performance,health status and welfare of market pigs?

The effects of transient stray voltage associated with an alternating current were evaluated in growing-finishing pigs from 9 to 22 weeks of age. Seventy-two pigs were assigned to 9 blocks of 8 animals each. In each block, the following treatments were randomly distributed: a constant voltage differential created between the feeder or drinker and the metallic floor (woven wire), at a level of 0 volt plus 2-volt pulses (0 V–2 V), 2 volts plus 3-volt pulses (2 V–5 V), 5 volts plus 3-volt pulses (5 V–8 V), and a control treatment without any voltage differential (0 V–0 V). The constant voltage was applied 24 h per day. The pulses of 3 s duration were in the form of an increase in the amplitude of the constant 60-Hz signal. One pulse appeared every 20, 40 and 100 s during the hour following feed distribution and every 60, 120 and 300 s during the rest of the day. The animals were fedad libitum and received fresh feed twice per day. Once during the 2-week periods at 9–10, 13–14, 17–18 and 21–22 weeks of age, the behaviour of the pigs was recorded during the hour following the two daily feed distributions. Animal weights and blood samples were taken every 2 weeks, from 9 to 21 weeks of age. No significant effect of transient stray voltage on any of the variables measured for the feeding, drinking, sitting or lying activities was found (p>0.05). At 9–10 weeks of age, the number of rooting bouts was higher for the 5 V–8 V treatment (p=0.03) and the number of events of butting the penmate was higher for the 2 V–5 V treatment (p=0.05). Although the water and feed intake did not differ between treatments (p0.39), the average daily gain of the control group was lower than that of treated groups (p=0.04) at 9 and 10 weeks of age, while the pigs submitted to a 2 V–5 V treatment had a higher daily gain than the pigs in the other treatment groups (p=0.05) at 17 and 18 weeks of age. Finally, the frequency of gastric ulceration and the metabolic profile were not affected by the treatments (p>0.05) except for the CO₂ and total protein concentrations (p0.04), where treatment effects were inconsistent among ages. Consequently, under the experimental conditions of the present study, no major impact of transient stray voltage on the health, growth or welfare of fattening pigs was observed.     

Effect of diet on markers of intestinal health in dogs

The effects of two popular commercial pet foods on faecal markers of microbial metabolism were investigated. Adult dogs were fed a dry, extruded diet and a moist, canned diet in a randomly assigned crossover design. Fresh faecal samples were collected for chemical and enzyme activity assays. Relative to the canned diet, the dry food resulted in decreased faecal pH and faecal indole, sulphide and ammonia concentrations and increased total short-chain fatty acid, acetic and propionic acid concentrations. Faecal beta-glucosidase, beta-glucuronidase, beta-galactosidase and nitroreductase activities were decreased in dogs fed the dry diet. These changes in microbial metabolic activity are consistent with beneficial effects of the dry diet on colonic health.     

Leptospirosis in raccoons in Quebec: 2 case reports and seroprevalence in a recreational area.

Raccoons may represent a source of leptospires for humans and domestic animals. We describe a case of severe interstitial nephritis associated with the serovar bratislava of Leptospira interrogans (1st report in wildlife), and the seroprevalence to 4 leptospire serovars in a recreational area in Quebec.     

In vitro Development of Buffalo Oocytes in Media-containing Fluids from Different Size Class Follicles

Studies were conducted to investigate the effect of supplementation of fluid from different sized class [small (SFF, < 3 mm), medium (MFF, 3-8 mm) and large (LFF, > 8 mm)] of normal and cystic (CFF) ovarian follicles in oocyte culture media on oocyte maturation rate and embryo development in vitro and to test the efficacy of follicular fluid (FF) from different size classes as a whole oocyte maturation medium. Results suggested that FF were capable of developing buffalo oocytes to embryonic stage in vitro although its efficacy was lower than that of serum. Regardless of high maturation rates after in vitro maturation (IVM) in media containing FF or IVM in whole FF, low blastocyst rates were obtained after in vitro fertilization (IVF) and culture of embryos. Follicular fluid from small follicles had significantly (p < 0.05) higher potential of developing buffalo oocytes to embryonic stage in vitro than that from medium and large follicles. Cystic FF was not capable of supporting development of buffalo oocytes in vitro.     

In vitro Growth and Maturation of Caprine Oocytes

This study was conducted to culture in vitro caprine pre-antral follicles for determining the competence of growth and maturation of oocytes and establishing a suitable culture system for oocyte maturation from pre-antral follicles. Two different culture methods (microdrop and agar gel clot) were employed to culture caprine pre-antral follicles. The pre-antral follicles were isolated from prepubertal goat ovaries by treatment with collagenase and DNase. The isolated pre-antral follicles were cultured in basic culture medium for 9 days (for growth). And oocytes were cultured in maturation culture medium for another 2 days for maturation. The result demonstrated that the growth rate of oocytes cultured in microdrops was significantly (p < 0.05) higher than that in agar gel clots, whereas the viability of oocytes in microdrops was considerably (p < 0.05) lower than that in agar gel clots. The oocytes grew over 150 microm in diameter, and two of 151 oocytes cultured in microdrops yielded morphologically abnormal first polar bodies. However, the size of oocytes cultured in agar gel approached to 120 microm in diameter and no polar body was produced.     

Comparison of Different Glycerol and Egg Yolk Concentrations Added to Tris‐based Extender for the Collared Peccaries (Tayassu tajacu) Semen Freezing

This study aimed to evaluate various concentrations of egg yolk (5, 10, or 20%) in combination with different concentrations of glycerol (3% or 6%) added to a Tris‐based extender on the post‐thaw characteristics of sperm obtained from Tayassu tajacu. For this purpose, semen from 10 sexually male mature collared peccaries was collected by electroejaculation and evaluated for sperm motility, vigour, viability, morphology and functional membrane integrity. The ejaculates were initially extended in Tris‐fructose plus egg yolk (5%, 10% or 20%). After cooling, the semen was added to Tris‐egg yolk plus glycerol (6% or 12%), resulting in a final concentration of 3% or 6% glycerol of the extender. Straws were frozen using liquid nitrogen and thawed in a water bath at 37°C for 30 s. The frozen–thawed semen was evaluated as reported for fresh semen. After thawing, a significant decrease was verified for sperm motility and vigour, for all the samples in comparison with fresh semen. However, no differences were evidenced among treatments for any sperm characteristics evaluated (p > 0.05), except for the combination between 10% egg yolk and 6% glycerol, which provided the worst preservation of functional membrane integrity (p < 0.05). The interactions between higher concentrations of egg yolk (20%) and glycerol (6%) and also between lower concentrations of the same substances (5% egg yolk and 3% glycerol) added to the Tris‐based extender negatively affected the preservation of the normal sperm morphology after thawing (p < 0.05). In conclusion, the use of Tris‐based extender added to 10% or 20% egg yolk plus 3% glycerol is recommended for effective sperm cryopreservation in collared peccaries.