Growth-related micromorphological characteristics of the porcine common carotid artery

The purpose of this study was to gain knowledge about the micromorphology of the porcine common carotid artery (CCA) during the period of growth over the bodyweight range of 10–40 kg. CCA samples from German landrace pigs (DL) aged either 2 or 3 months (DL-2 and DL-3) were compared with samples from Göttingen minipigs (GM) aged either 18 or 40 months (GM-18 and GM-40) using transmitted light (phase-contrast mode) and transmission electron microscopy. The GM-18, GM-40 and the DL-3 groups had typical muscular artery histological characteristics. Contrasting to this, the 2-month-old DL pigs had a transitional artery type being characterized by a significantly higher proportion of elastic fibres and a significantly lower number of smooth muscle cells than did the 1 month older DL-3. During the period of maturation, the tunica media of the CCA in GM animals thickened by 1.3× and in DL animals by 2.5× resulting in an overall increased vessel wall thickness. The cumulated thickness of the tunica interna (endothelium, stratum subendotheliale and internal elastic lamina) and the tunica media (including the external elastic lamina) of DL-3 and GM-40 pigs were similar to each other and comparable to that of humans. With an increasing vessel wall thickness, the luminal diameter decreased in GM by 19% and in DL by 11%. Additionally, in the older age groups, GM-40 and DL-3, the internal elastic lamina principally was continuous, but there were also interrupted large segments of elastic lamina separated by gaps. In addition, the principal internal elastic lamina was duplicated in several places.     

Collateral vessel development after chronic bilateral common carotid artery occlusion in the dog

The functional response to occlusion of arteries supplying the head has been found to be much less severe in th dog than in man, indicating that a more significant collateral development occurs in the dog. To document the anatomic response to chronic occlusion of vessels supplying the head, patterns of collateral vessel growth and development were studied by corrosion casting in adult mongrel dogs 8 weeks after bilateral ligation of the common carotid artery. Dissection of the casts revealed two consistent and bilateral anastomotic connections: (i) internal carotid artery to maxillary artery (anastomotic artery) and (ii) internal carotid artery to ascending pharyngeal artery. Also present in all of the casts was a connection between one common carotid artery and both vertebral arteries, which has been designated as the deep collateral vessel. Significant collateral connections did not occur between the orbital vessels or between analogous vessels of the right and the left sides.     

High-rise syndrome in cats

High-rise syndrome was diagnosed in 132 cats over a 5-month period. The mean age of the cats was 2.7 years. Ninety percent of the cats had some form of thoracic trauma. Of these, 68% had pulmonary contusions and 63% had pneumothorax. Abnormal respiratory patterns were evident clinically in 55%. Other common clinical findings included facial trauma (57%), limb fractures (39%), shock (24%), traumatic luxations (18%), hard palate fractures (17%), hypothermia (17%), and dental fractures (17%). Emergency (life-sustaining) treatment, primarily because of thoracic trauma and shock, was required in 37% of the cats. Nonemergency treatment was required in an additional 30%. The remaining 30% were observed, but did not require treatment. Ninety percent of the treated cats survived.     

Duplex ultrasonography of the common carotid artery and external jugular vein of cows

OBJECTIVE: To determine blood flow patterns in the common carotid artery and external jugular vein in cows before and after sedation achieved by administration of xylazine hydrochloride. ANIMALS: 30 clinically normal Swiss Braunvieh cows. PROCEDURE: A 5.0-MHz sector transducer was used to examine the common carotid artery and external jugular vein before and after cows were sedated by administration of xylazine. Several variables were calculated, including diameter of the blood vessels, blood flow velocity, and flow-time volume. RESULTS: The common carotid artery before sedation had a maximum systolic velocity of 89 +/- 8.5 cm/s, maximum diastolic velocity of 36 +/- 6.0 cm/s, mean velocity of 35 +/- 5.4 cm/s, and flow-time volume of 28.2 +/- 3.48 cm3/s. In all cows, sedation achieved by administration of xylazine resulted in a significant decrease in velocity of arterial blood flow and flow-time volume. The external jugular vein before sedation had a maximum velocity of 65 +/- 8.3 cm/s, maximum velocity of retrograde venous blood flow of 20 +/- 6.6 cm/s, and flow-time volume of 29.7 +/- 5.42 cm3/s. These values decreased significantly after cows were sedated by administration of xylazine. CONCLUSIONS AND CLINICAL RELEVANCE: Doppler ultrasonography is particularly suitable for evaluation of blood flow patterns in the common carotid artery and external jugular vein of healthy cows. The results reported here provide a basis for use in examination of cows with cardiac and blood vessel disease.     

FeLV-FAIDS-induced immunodeficiency syndrome in cats

Findings are reviewed, relevant to elucidation of the pathogenic, genetic and biochemical properties of a single, genetically heterogeneous isolate of feline leukemia virus (FeLV-FAIDS) shown to induce fatal immunodeficiency disease in nearly 100% of inoculated cats. Hypotheses are suggested which pertain to the mechanism of T-cell killing by this virus, and which extrapolate findings in the FeLV-FAIDS animal model to AIDS induced in humans by human immunodeficiency virus (HIV).     

Hypereosinophilic syndrome in two cats

Two cats showing chronic vomiting, diarrhea and weight loss were found to have leukocytosis with marked eosinophilia. Both cats were diagnosed with hypereosinophilic syndrome by the findings of increased eosinophils and their precursors in the bone marrow, eosinophilic infiltration into multiple organs, and exclusion of other causes for eosinophilia. Although cytoreductive chemotherapy with hydroxycarbamide and prednisolone was performed, these two cats died 48 days and 91 days after the initial presentation.     

Taurine deficiency syndrome in cats

Taurine deficiency occurs in a large number of cats fed unfortified commercial diets. Deficiency arises because cats are unable to absorb all the taurine in processed diets and/or are unable to synthesize the deficit between absorption and requirement, which makes taurine an essential amino acid for cats. Taurine-depleted cats develop retinal degeneration, cardiomyopathy, altered white-cell function, and abnormal growth and development. Taurine deficiency is best estimated from the plasma-taurine concentration, with values less than 30 mumol/l considered deficient.     

Peripheral pulmonary artery stenosis in three cats

Case 1 involved a 4-month-old intact male Somali cat in which peripheral pulmonary artery stenosis (PPS) was recognized after a cardiac murmur remained following patent ductus arteriosus ligation. Case 2, which involved a 1-year-old neutered male Norwegian Forest cat, and Case 3, which involved a 6-month-old intact female American Curl cat, were referred, because of cardiac murmurs. Grades III to IV/VI systolic heart murmurs were auscultated at the left heart base in all 3 cats. All cases showed bilateral pulmonary artery stenosis, although there were no associated clinical signs. In Cases 1 and 2, the pressure gradient through the stenosis decreased after treatment with atenolol.