Comparison of the tibial mechanical joint orientation angles in dogs with cranial cruciate ligament rupture

Use of the tibial mechanical joint orientation angles is now the standard of care for evaluating tibial deformities, although they have not been used to evaluate dogs with cranial cruciate ligament (CrCL) rupture. The objective of this study was to compare the tibial mechanical joint orientation angles and tibial plateau angle (TPA) between dogs with bilateral CrCL rupture (BR) and unilateral CrCL rupture with (UR-SR) and without subsequent contralateral CrCL rupture (UR-w/o-SR) as risk factors for subsequent contralateral CrCL rupture. Twenty dogs (21.7%) were classified as BR, 38 (41.3%) were classified as UR-SR, and 34 (37.0%) were classified as UR-w/o-SR. The tibial mechanical joint orientation angles and TPA, in the range studied (< 35°), were not statistically different for dogs with BR, UR-SR, and UR-w/o-SR, and were not significant risk factors for subsequent contralateral CrCL rupture.     

Retrospective risk factor assessment for complication following tibial tuberosity transposition in 137 canine stifles with medial patellar luxation

This study identified risk factors for complication following tibial tuberosity transposition by retrospective examination of cases that used various surgical techniques. Records and radiographs of 113 dogs with 137 stifles undergoing tibial tuberosity transposition for medial patellar luxation were reviewed. Patient-specific factors, surgical factors, and complication information were recorded. Owners were contacted as necessary to attain a minimum of 30 days follow-up. Of 137 stifles, 59 (43%) had complications, with 24 (18%) identified as major complications. Factors significantly associated with reduced risk of complication included increased age [odds ratio (OR) 0.8] and concurrent cranial cruciate ligament rupture (OR 0.3). Factors significantly associated with increased risk of complication included large breed compared to toy breed (OR 5.5), increased weight (OR 1.3), and use of a screw for tibial tuberosity fixation (OR infinity). While significant, these associations do not imply causality and prospective study is necessary to determine the ideal fixation method for individual patients.     

Lung toxicity of a vapor-grown carbon fiber in comparison with a multi-walled carbon nanotube in F344 rats

Carbon fibers have excellent physicochemical and electrical properties. Vapor-grown carbon fibers are a type of carbon fibers that have a multi-walled carbon tube structure with a high aspect ratio. The representative vapor-grown carbon fiber, VGCF^TM-H, is extremely strong and stable and has superior thermal and electrical conductivity. Because some high-aspect-ratio multi-walled carbon nanotubes (MWCNTs) have been reported to have toxic and carcinogenic effects in the lungs of rodents, we performed a 13-week lung toxicity study using VGCF^TM-H in comparison with one of MWCNTs, MWNT-7, in rats. Male and female F344 rats were intratracheally administered VGCF^TM-H at doses of 0.2, 0.4, and 0.8 mg/kg bw or MWNT-7 at doses of 0.4 and 0.8 mg/kg bw once a week for 8 weeks and then up to week 13 without treatment. The lung burden was equivalent in the VGCF^TM-H and MWNT-7 groups; however, the lung weight had increased and the inflammatory and biochemical parameters in the broncho-alveolar lavage fluid and histopathological parameters, including inflammatory cell infiltration, alveolar type II cells proliferation, alveolar fibrosis, pleural fibrosis, lung mesothelium proliferation, and diaphragm fibrosis, were milder in the VGCF^TM-H group than in the MWNT-7 group. In addition, the proliferating cell nuclear antigen (PCNA)-positive index in the visceral and pleural mesothelium was significantly higher in the MWNT-7 group than in the controls, but not in the VGCF^TM-H group. Thus, the results of this study indicate that the lung and pleural toxicities of VGCF^TM-H were less than those of MWNT-7.     

The anomalous Hall effect and magnetic monopoles in momentum space

Efforts to find the magnetic monopole in real space have been made in cosmic rays and in particle accelerators, but there has not yet been any firm evidence for its existence because of its very heavy mass, approximately 10(16) giga-electron volts. We show that the magnetic monopole can appear in the crystal momentum space of solids in the accessible low-energy region (approximately 0.1 to 1 electron volts) in the context of the anomalous Hall effect. We report experimental results together with first-principles calculations on the ferromagnetic crystal SrRuO3 that provide evidence for the magnetic monopole in the crystal momentum space.     

Experimental infection of pigs with different doses of the African swine fever virus Armenia 07 strain by intramuscular injection and direct contact

We experimentally infected pigs with the African swine fever virus (ASFV) Armenia 07 strain (genotype II) to analyze the effect of different dose injections on clinical manifestations, virus-shedding patterns, histopathology, and transmission dynamics by direct contact. Each three pigs and four pigs were injected intramuscularly with 0.1 fifty percent hemadsorbing doses (HAD₅₀)/ml, 10¹ HAD₅₀/ml and 10⁶ HAD₅₀/ml of ASFV Armenia 07 strain, respectively. Each two of three pigs injected with 0.1 HAD₅₀/ml and 10¹ HAD₅₀/ml died by 10 days post inoculation. All pigs had a gross lesion of splenomegaly. Perigastric and renal lymph nodes were enlarged and resembled blood clots in nine of ten pigs. It was revealed that 0.1 HAD₅₀/ml of this ASFV was sufficient to infect healthy pigs by intramuscular injection and caused sub-acute lethal disease. For the transmission study, two 8-week-old pigs were injected intramuscularly with 10³ HAD₅₀/ml of the same virus. Each of the experimentally inoculated pigs was co-housed with two 8-week-old naive pigs. All contact pigs exhibited clinical manifestations at 6 or 7 days after the experimentally inoculated pigs developed pyrexia. These findings suggest that this strain may spread slowly within a herd. Histologically, lymph nodes resembled blood clots were formed by severe blood absorption and followed hemorrhage result of disruption of the lymphoid sinus filling with absorbed red blood cells. The severity of the gross and histological lesions depended on duration after infection, regardless of the difference of injection doses in this study.     

Economic effects of using sexed semen in Japanese dairy herds

Dairy farm agricultural income should increase when sexed semen is used instead of unsexed semen. This study simulated three scenarios: using unsexed semen (N), using X sperm of Holstein and unsexed semen of Japanese Black (H), and using X sperm of Holstein and Y sperm of Japanese Black (HJ). Two management scenarios were considered: conventional management (CONV); and the use of Japanese Black semen with surplus cows to produce F₁s where sufficient replacement female Holstein calves were obtained for maintenance (MAINT). In CONV, the agricultural incomes of H and HJ were 610 000–2 400 000 yen higher than that of N. The agricultural income increased when the difference in the prices between Holstein males and average F₁ male/female calves was 34 000–50 000 yen, that between Holstein male and female calves was 80 000–110 000 yen, and that between F₁ male and female calves was 50 000–90 000 yen. Therefore, the agricultural income can be increased by using sexed semen to select calves of a more valued breed and sex.