A Novel Technique for Partial V-shaped Zygomatic Arch Ostectomy for Excision of Zygomatic Salivary Glands in Dogs.

The present study described a novel technique for a partial V-shaped ostectomy of the zygomatic arch (ZA) for surgical excision of the zygomatic salivary glands (ZSG) in dogs and addressed advantages and disadvantages related to this procedure. The study was conducted on 6 clinically healthy mongrel dogs. A 3-4 cm curvilinear transcutaneous incision was performed parallel to the dorsal margin of the ZA. An additional 2 cm vertical incision was performed perpendicular to the former one forming a T-shaped incision over the ZA. The skin, subcutaneous tissue, and periosteum over the ZA were dissected and reflected laterally. At 0.5 cm from the orbital ligament, a V-shaped segment from the ZA was resected using an electrical saw. The base of the V-shaped segment was 1.5 cm wide and its apex was 0.5 cm from the ventral margin of the ZA. A combination of sharp and blunt dissection was used to dissect and excise the ZSG from the surrounding tissues. The periosteal flaps were coaptated in a simple continuous pattern. The subcutaneous tissue and skin were closed as usual. The new approach was a feasible technique for the excision of the ZSGs without considerable postoperative complications in dogs. The novel V-shaped partial ostectomy of the ZA technique is reliable, satisfactory, and relatively less invasive for surgical excision of ZSGs in dogs. Further work should be conducted on clinical cases.

Effect of suckling cow's milk or milk replacer on abomasal luminal pH in dairy calves.

Abomasal ulceration occurs commonly in suckling calves, and the cause for the high prevalence of abomasal ulceration is unknown. We hypothesized that diet may play a role in the etiopathogenesis of abomasal ulceration. Six male dairy calves with an abomasal body cannula suckled fresh Holstein cow's milk, all milk-protein milk replacer, or combined milk- and soy-protein milk replacer twice daily at 12% of body weight/d. Abomasal luminal pH was measured every second for 24 hours by using a miniature glass pH electrode. Mean 24-hour abomasal luminal pH for all milk-protein milk replacer (3.22) and combined milk- and soy-protein milk replacer (3.27) were similar but significantly (P < .05) higher than that for cow's milk (2.77; standard error = 0.08). Both milk-replacer formulations failed to clot after the addition of chymosin, whereas cow's milk clotted within 2 minutes. The in vitro titration curve of cow's milk and all milk-protein milk replacer were similar, but different to that of combined milk- and soy-protein milk replacer. The osmolalities of all milk-protein milk replacer (375 mOsm/kg) and combined milk- and soy-protein milk replacer (410 mOsm/kg) were greater than that of cow's milk (278 mOsm/kg). The slightly lower mean abomasal luminal pH in calves suckling cow's milk, compared to milk replacer, was probably due to clotting of cow's milk, with extrusion of low pH whey, and a slower rate of abomasal emptying caused by the hyperosmolality of milk replacer. Examination of our results suggests that suckling cow's milk may increase the prevalence of abomasal ulceration by decreasing mean luminal pH, although this remains to be determined.

Effect of an orally administered antacid agent containing aluminum hydroxide and magnesium hydroxide on abomasal luminal pH in clinically normal milk-fed calves.

OBJECTIVE: To determine the effects of a commercially available orally administered antacid agent containing aluminum hydroxide and magnesium hydroxide on abomasal luminal pH in clinically normal milk-fed calves. DESIGN: Randomized trial. ANIMALS: 5 male dairy calves. PROCEDURE: Throughout the study, calves were fed milk replacer at 7:30 AM and 7:30 PM. Cannulae for pH electrodes were placed in the abomasal body and pyloric antrum. Treatments consisted of oral administration of a high (50 ml) or low (25 ml) dose of the antacid agent and oral administration of milk replacer alone (control). Antacid was given at 7:30 AM, 3:30 PM, and 11:30 PM, and luminal pH was monitored continuously for 24 hours, beginning 15 minutes before administration of the first dose of antacid. RESULTS: Administration of the first dose of antacid at the time of the morning feeding resulted in an increase in mean abomasal body luminal pH of < 1 pH unit, whereas administration of the second and third doses of the antacid caused transient (< 3 hours) increases in mean luminal pH of approximately 1.5 (low dose) and 2.5 (high dose) pH units. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that clinically normal milk-fed calves given a commercially available antacid agent, PO, will have a transient increase in abomasal luminal pH. Such agents may, therefore, have a role in the treatment of abomasal ulceration in calves; however, the long-term effects of orally administered antacid agents in milk-fed calves and the clinical efficacy of such agents in treating abomasal ulceration remain to be determined.