Search Results

You are looking at 1 - 5 of 5 items for

  • Author or Editor: A. Franco x
  • Refine by Access: All Content x
Clear All Modify Search

Summary

Histomorphometric and scanning electron microscopic analyses were carried out on 74 embryos and fetuses and 20 sheep (early postnatal to adult age). Histodifferentiation of the rumen took place at 33 days of fetal life. Ruminal pillars were observed at 42 days, and at 61 days, ruminal papillae appeared as evaginations of the epithelial stratum basale. Neutral mucopolysaccharides first appeared in epithelial cells at 46 days of fetal life; thereafter, numbers decreased gradually and subsequently stabilized in postnatal life. Acid mucopolysaccharides, mucins, and mucoid compounds were not detected. Age and diet were recognized as factors that determine the structure of the ruminal mucosa. Growth curves and formulas were set out for each tissue layer.

Free access
in American Journal of Veterinary Research

Abstract

In collaboration with the American College of Veterinary Radiology

Open access
in Journal of the American Veterinary Medical Association

Summary

Histomorphometric and scanning electron microscopic analyses were performed on 74 embryos and fetuses and 20 sheep (early postnatal to adult age). Histologic differentiation of the omasum took place at 33 days of fetal life, with the appearance of first-order laminae. Second-, third-, and fourth-order laminae appeared at 39, 50, and 59 days, respectively. Neutral mucopolysaccharides first appeared in epithelial cells at 46 days of fetal life, decreasing quantitatively until birth, before subsequently stabilizing in postnatal life. Acid mucopolysaccharides, mucins, and mucoid compounds were not detected. Growth curves and formulas were constructed for each tissue layer. Initial tests involved multiplicative (y = axb), exponential (y = EXP [a + bx]), linear (y = a + bx), and polynomial models (y = a + bx + cx2 + dx3).

Free access
in American Journal of Veterinary Research

Abstract

Objective

To analyze the vitreal amino acid concentrations in dogs with breed-related primary glaucoma to determine whether excitotoxic amino acids associated with retinal ganglion cell death in other species were present in affected dogs.

Samples

11 normal control and 10 glaucomatous canine eyes.

Procedure

Amino acid analyses were performed by high-pressure liquid chromatography in masked manner.

Results

Eyes from dogs with primary glaucoma had significantly high vitreal glutamate concentration, compared with values for eyes of clinically normal control dogs. Mean (± SD) glutamate concentrations were 31.7 ± 12.4 and 6.9 ± 6.3 μM in glaucomatous and normal eyes, respectively (P < 0.0001). Eyes from dogs with glaucoma also had lower vitreal glycine (37.0 ± 17.0 vs 59.4 ± 28.2 μM; P < 0.043) and higher of vitreal tryptophan (39.0 ± 22.8 vs 17.5 ± 11.2 μM; P < 0.012) concentrations, compared with values for normal eyes.

Conclusion

Glutamate concentration potentially toxic to retinal ganglion cells is associated with the pathogenesis of primary glaucoma in dogs. Increased glutamate concentration provides evidence of an ischemic mechanism for retinal ganglion cell death and optic nerve atrophy in dogs with glaucoma.

Clinical Relevance

The emphasis on reduction and normalization of high intraocular pressure as the primary focus of treatment for glaucoma in dogs should be augmented by other therapeutic approaches. (Am J Vet Res 1997;58:864–867)

Free access
in American Journal of Veterinary Research