Intestinal sclerosis with pseudo-obstruction in three dogs

Intestinal sclerosis causing chronic intestinal pseudo-obstruction was diagnosed in 3 dogs. The pseudo-obstruction was characterized by vomiting and weight loss of 2 weeks' to 3 months' duration. A patent intestinal lumen was determined by contrast radiography and verified at surgery. Intestinal biopsy revealed diffuse atrophy, fibrosis, and mononuclear cell infiltration of the tunica muscularis. Each dog was euthanatized because of a progressive, deteriorating clinical course.     

Clinical response of nasal adenocarcinoma to cisplatin chemotherapy in 11 dogs.

In 11 dogs with nasal adenocarcinoma, IV treatment with 2 to 8 cycles of cisplatin at a dosage of 60 mg/m2 of body surface, given at 3-week intervals, resulted in a survival time of 8 to 128 weeks (mean, 32.7 weeks; median, 20 weeks). Radiography revealed complete remission in 2 dogs and partial remission in 1 dog, for an overall response rate of 27%. Clinical problems such as nasal discharge (n = 11), sneezing (n = 6), and epistaxis (n = 4) resolved in 1 to 2 weeks in all dogs after beginning chemotherapy.     

Visual and nonvisual auditory systems in mammals. Anatomical evidence indicates two kinds of auditory pathways and suggests two kinds of hearing in mammals

Examination of the structural organization of the auditory system of the brain stem shows that the system is composed of a number of separate ascending pathways. This suggests that there may be at least two auditory systems, analogous to the rod and cone pathways in vision. We examined this possibility by investigating the variation in relative size of the medial and lateral superior olivary nuclei in a number of different mammalian species. The lateral superior olive is present in the hedgehog (an insectivore), cat (acarnivore), and squirrel monkey a(primate), but the medial superior olive is absent in the hedgehog. In a group of animals of the same taxonomic order (rodents) the lateral superior olive was present in all species examined, but the medial superior olive was almost wholly absent in the mouse and very prominent in the chinchilla and guinea pig. The absence of the medial superior olive in some animals is surprising because recent anatomical and physiological work has implicated the nucleus in auditory localization. Because of this implication, the medial and lateral olivary nuclei were examined in three species of bat and one dolphin, all echolocating animals. The medial superior olive was absent in these animals, and the lateral superior olive was prominent. These observations support the idea that the medial and lateral superior olives are nuclei on two different ascending auditory systems. It was also noted that the medial superior olive was always well developed in animals with well-developed eyes, and this suggested that the nucleus is in some way related to the visual system. We examined this idea by studying the relation between the numbers of cells in the medial superior olive and in the nucleus of the 6th cranial nerve (one of the motor nuclei concerned with eye movement) in a number of mammalian species. An approximately linear function was found between the sizes of the 6th nucleus and of the medial superior olive in three primates with cone-cell retinas (squirrel monkey, man, and macaque) and four rodents with rod-cell retinas (mouse, rat, guinea pig, and chinchilla). The cell numbers for the ground squirrel (a rodent with cone-cell retina) fitted an extension of the primate curve, and the cell numbers for the cat (in whose retina rods predominate) fitted an extension of the rodent curve. Thus, it is clear that the medial superior olive is related to the visual system, and that it is present in animals with cone-cell fovea and retina (diurnalanimals) and animals with rod-cell retina (that is, nocturnal animals) having good vision. In nonvisual nocturnal animals the nucleus is small or absent. The medial superior olive is probably not concerned with auditory localization in the psychophysical sense but is probably concerned with the movement of head and eyes in the direction of a sound in space. Localization in the psychophysical sense and fine auditory discrimination probably depend upon the ascending pathway which includes the lateral superior olive.     

A seroepidemiologic survey of antibody to bluetongue virus in Alabama cattle

Bluetongue (BT) is an insect transmitted viral disease of sheep that often causes mild or inapparent disease but rarely causes severe disease in cattle. Until recently, bluetongue viral infection was believed to be more prevalent in the Western United States, as compared with other regions of the country. However, a national survey for bluetongue antibody and clinical evidence of the disease in the Southeastern United States prompted the present investigation that was designed to determine the serological prevalence of BT virus in Alabama cattle. Results of the study demonstrated that 16% of the samples collected from 1,500 cattle in 64 of the 67 counties were positive. The prevalence of positive cattle in the western part of the State was significantly higher (P less than .001) than the prevalence in the eastern half of the State. On a herd basis, 52% of all herds tested had positive animals. Results of this study suggest that bluetongue infection is more common in the Southeastern United States than previously suspected.     

Influence of anions on dispersion and physical properties of the A horizon of a Red-brown earth

Three groups of anions were distinguished in order of effectiveness with respect to the dispersion and flocculation of soil samples treated with Fe(III) polycations: phosphate and fulvate citrate, oxalate, silicate and tartrate and salicylate, catechol, aspartate, lactate and acetate. This was also the order of the amount of anion adsorbed by the soil. The addition of phosphate and fulvate to soil samples with a net charge of zero lowered the zero point of charge producing particles with a net negative charge. This increased the amount of dispersible clay present from 0 to 9% by weight of soil. The sorption of phosphate and fulvate by soil samples with a net positive charge reduced the zero point of charge and caused flocculation of dispersed clay. Electrophoretic and electron microscopic studies confirmed the dispersion-flocculation phenomena.Treatments which produced dispersed clay led to increased bulk densities, plastic limits and moduli of rupture but lower porosities, water holding capacities and hydraulic conductivities. The sorption of anions on soil samples with a net charge of zero reduced friability.     

Responses of seasonally anovulatory mares to daily administration of thyrotropin-releasing hormone and(or) gonadotropin-releasing hormone analog

Seventeen seasonally anovulatory light horse mares were treated daily, starting January 5 (d 1), for 28 d with GnRH analog (GnRH-A; 50 ng/kg BW) and(or) thyrotropin-releasing hormone (TRH; 5 microg/kg BW) in a 2 x 2 factorial arrangement of treatments to test the hypothesis that combined treatment may stimulate follicular growth and development. Ovaries were examined via ultrasonography and jugular blood samples were collected every 3 d. Frequent blood samples were collected after treatment injections on d 1, 2, 4, 7, 11, 16, and 22; on d 29, all mares received an i.v. mixture of GnRH, TRH, sulpiride, and EP51389 (a growth hormone secretagogue) to assess pituitary responsiveness. No consistent effects (P > 0.1) of treatment were observed for plasma LH, FSH, prolactin, or thyroxine concentrations in samples collected every 3 d. The only effect on ovarian follicle numbers was a reduction in number of follicles 11 to 19 mm in diameter due to TRH treatment (P = 0.029). No mare ovulated during treatment. On the days of frequent sampling, mean LH (P = 0.0001) and FSH (P = 0.001) concentrations were higher in mares receiving GnRH-A and tended to increase from d 1 through 7. In contrast, mean prolactin (P = 0.001) and thyroid-stimulating hormone (P = 0.0001) concentrations were high in mares receiving TRH on d 1 but rapidly decreased thereafter. When mares were administered the secretagogue mixture on d 29, the LH response was greater (P = 0.0002) in mares that had previously received GnRH-A but the FSH response was not affected (P > 0.1); the prolactin response was greater (P = 0.014) and the TSH response was smaller (P = 0.0005) in mares that had previously received TRH. Surprisingly, an immediate growth hormone response to EP51389 was absent in all mares. In conclusion, daily GnRH-A treatment stimulated plasma LH and FSH concentrations immediately after injection; although no long-term elevation in preinjection concentrations was achieved, the responses gradually increased over time, indicating a stimulation of gonadotropin production and storage. Daily treatment with TRH stimulated plasma TSH and prolactin concentrations, but the response diminished rapidly and was minimal within a few days, indicating a depletion of pituitary stores and little or no stimulation of production. There was no beneficial effect of adding TRH treatment to the daily GnRH-A regimen.     

Neuronal ceroid-lipofuscinosis in Borderdale sheep

AIM: To describe the gross and histological lesions of a neurological disease in Borderdale sheep characterised clinically by blindness and circling, as a basis to its classification. METHODS: Formalin-fixed tissues were processed into paraffin wax and epoxy resin for light and electron microscopy of variously stained sections. RESULTS: Lesions were those of a lysosomal storage disease with severe neurodegeneration of the cerebral cortex. The staining reactions, autofluorescence and ultrastructure of storage material allowed the diagnosis of neuronal ceroid-lipofuscinosis associated with the accumulation of subunit-c of mitochondrial ATP synthase. CONCLUSIONS: The severity of neurodegeneration and minor differences in the ultrastructure of storage material implied that this was a different disease from other forms of ovine ceroid-lipofuscinosis that accumulate subunit-c of mitochondrial ATP synthase. An autosomal recessive mode of inheritance is considered probable. Although of only minor economic importance, this disease may be important to research into the group of ceroid-lipofuscinoses as a whole.