Effects of acetylcysteine and migration of resident eosinophils in an in vitro model of mucosal injury and restitution in equine right dorsal colon

OBJECTIVES: To evaluate the in vitro protective effects of acetylcysteine and response of resident mucosal eosinophils in oxidant-induced injury to tissues of right dorsal colon of horses. ANIMALS: 9 adult horses. PROCEDURE: Gastrointestinal mucosa was damaged in vitro with 3 mM hypochlorous acid (HOCl), with and without prior exposure to 6mM acetylcysteine. Control tissues were not exposed to HOCl or acetylcysteine. Control and damaged tissues were incubated in Krebs-Ringer-bicarbonate solution and tissue resistance measured during 240 minutes. Tissue permeability to radiolabeled mannitol was also used to assess mucosal barrier integrity. Tissues were examined by light microscopy before and after HOCl exposure and during and after incubation. RESULTS: Exposure to HOCl caused tissue damage and decreased tissue resistance. Restitution did occur during the incubation period. Eosinophils were located near the muscularis mucosae in freshly harvested tissues and migrated towards the luminal surface in response to HOCl-induced injury. Compared with tissues treated with HOCl without acetylcysteine, pretreatment with acetylcysteine prevented HOCl-induced tissue damage, changes in resistance, and histologically detectable eosinophil migration. The permeability to mannitol increased to the same extent in tissues treated with HOCl alone or with acetylcysteine and HOCl. CONCLUSIONS AND CLINICAL RELEVANCE: Eosinophils migrated toward the mucosal surface in equine colon in response to oxidant-induced damage in vitro. This novel finding could be relevant to inflammation in equine colon and a pathophysiologic feature of many colonic diseases. Acetylcysteine protected the mucosa against oxidant-induced injury and may be useful as a treatment option for various gastrointestinal tract disorders in horses.     

Interaction between genotype and dietary concentrations of methionine for immune function in commercial broilers

1. Growth, antibody response to sheep red blood cells (SRBC) and resistance to Escherichia coli were measured in broiler female chicks received from 4 (n = 100 in each) commercial genotypes (A, B, C and D) and fed with maize-soybean-deoiled rice bran based diets containing 4 concentrations of methionine (3.91, 4.46, 5.00 and 5.54 g/kg). The diets were fed ad libitum from 1 to 49 d of age. 2. Body weight gain and weight gain/food intake at 2 week intervals, response of broilers to inoculation of 0.5 ml of SRBC (0.5 or 2.5%), 0.1 ml of E. coli (10(-4) dilutions) culture, and 100 microg phytohaemogglutinin-P (PHA-P) at 43 d of age were measured. The responses to SRBC and E. coli inoculation were recorded at 5 d post inoculation (PI), while the responses to PHA-P were recorded at 12 and 24 h PI. 3. Genotype by methionine interaction was not significant for body weight gain, but significant differences in weight gain were observed among different genotypes. Variation in methionine concentration did not influence body weight gain or weight gain/food intake at 1 to 14, or 42 d of age. At 28 d of age, chicks fed on the 3.91 g methionine/kg diet weighted significantly less than those on the other methionine concentrations. Genotype by methionine interaction was observed for food efficiency at 0 to 28 d of age but not at other ages. 4. Antibody titres against SRBC and heart and air sac lesion score to E. coli challenge were not influenced by genotype-methionine interaction. Chicks given higher concentrations of methionine had higher antibody titres and greater cutaneous basophilic hypersensitivity (CBH) response than those given low levels of methionine. Also, variation was observed in expression of CBH response to PHA-P among different genotypes. 5. It may be concluded that, although the commercial broiler chicks do not require more than 3.91 g methionine/kg for optimum growth and food efficiency, the immunity in terms of CBH response and antibody production to SRBC increased with the concentration of methionine in the diet in the majority of genotypes, indicating a higher methionine requirement for immunity than for weight gain.     

Effects of cyclophotocoagulation with a neodymium:yttrium-aluminum-garnet laser on corneal sensitivity,intraocular pressure,aqueous tear production,and corneal nerve morphology in eyes of dogs

OBJECTIVE: To determine effects of cyclophotocoagulation via administration of 100 J with a neodymium:yttrium aluminum garnet (Nd:YAG) laser on corneal touch threshold (CTT), intraocular pressure (IOP), aqueous tear production, and corneal nerve morphology in eyes of dogs. ANIMALS: 15 dogs. PROCEDURE: Noncontact Nd:YAG laser was transsclerally applied (10 applications; 25 W for 0.1 seconds for each application to each of 4 quadrants) to the ciliary body of the left eye of 15 dogs; the right eye was the control eye. Corneal integrity, CTT, tear production as measured by the Schirmer tear test (STT), and IOP were evaluated for 14 days following laser treatment. On day 14, dogs were euthanatized, eyes harvested, and corneas stained with gold chloride. Major nerve bundles were analyzed by use of a drawing tube attached to a light microscope, and maximum diameters were measured by use of image analysis software. RESULTS: All laser-treated eyes had significantly higher CTT values, compared with control eyes. Six of 15 laser-treated eyes developed ulcerative keratitis. On most days, IOP was significantly lower in laser-treated eyes in both morning and evening. Laser-treated eyes had a significant decrease of approximately 1 nerve bundle/corneal quadrant. Values for STT or nerve bundle diameters did not differ significantly. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of 100 J with a Nd:YAG laser effectively reduced IOP while increasing CTT and caused a significant decrease in number, but not diameter, of major corneal nerve bundles. Nerve damage and corneal hypoesthesia are etiologic factors in ulcerative keratitis following Nd:YAG cyclophotocoagulation.     

Vaccination of donkeys against Babesia equi using killed merozoite immunogen

Protective efficacy of a killed Babesia equi immunogen was assessed in donkeys. The immunogen was prepared from B. equi infected blood so as to contain lysate of 2 x 10(10) parasitised erythrocytes per dose. The immunogen was mixed with an adjuvant Quil A (3mg) and inoculated into four susceptible donkeys (group I). A booster inoculation was given after 21 days of first inoculation followed by challenge with fresh infected blood containing 1x10(11) parasitised erythrocytes 14 days later. Two groups of two donkey each were included as adjuvant only control (group II) and uninoculated control (group III), respectively. After challenge, donkeys were observed for a period of 4 weeks. The immunised donkeys (group I) showed significantly high (P<0.05%) enzyme linked immunosorbant assay (ELISA) antibody titres and significantly high (P<0.05%) stimulation indices (SI) in lymphocyte proliferation assay (LPA) than that of groups II and III donkeys from day 14 PI and day 7 PI onwards, respectively. All the immunised donkeys withstood lethal challenge, whereas, control donkeys died within 10 days post-challenge (PC). Parasitaemia rose to mean maximum 8.0+/-6.0% for 5-7 days in group I donkeys after challenge, whereas, it rose to 55.5% in control groups. The percent rise in rectal temperature, total leucocyte count (TLC), fall in haemoglobin (Hb) was less severe in immunised group as compared to the control groups. Two immunised-challenged donkeys were splenectomised recovery. No parasites appeared in the blood during the observation period following splenectomy 4-week. Three times increase in skin-fold thickness at 24h of intradermal inoculation prior to challenge in group I donkeys was observed, thus, indicating a good in vivo cell mediated immunity. It can be concluded that the B. equi immunogen along with adjuvant Quil A, used in the present study, was optimum to elicit a strong immune response against B. equi in experimental donkeys.     

Responses of the ultimobranchial gland to vitamin D3 treatment in freshwater mud eel,Amphipnous cuchia,kept in different calcium environments

Freshwater mud eel, Amphipnous cuchia, were injected intraperitoneally daily with 100 ng of vitamin D3/100 g body weight and maintained in media containing either no calcium or different calcium concentrations. The eels were killed after 1, 3, 5, 10 and 15 days following the treatment and their serum calcium levels were measured. The ultimobranchial glands were fixed and processed using the routine paraffin method for histological studies. The results of the present study indicate that vitamin D3 can induce hypercalcaemia in eels kept in different calcium environments. Also, the ultimobranchial glands became hyperactive following vitamin D3 treatment. It is concluded that in mud eels, the gland has a calcium-regulating function.     

Carbon fibres and plasma-preserved tendon allografts for gap repair of flexor tendon in bovines: clinical,radiological and angiographical observations

Twenty-four tenorrhaphies were performed at the mid-metatarsal region in 12 crossbred calves under xylazine-ketamine spinal analgesia. A 2.5-cm long gap was created in the superficial digital flexor (SDF) tendon and immediately repaired with carbon fibres in the animals of group I and with plasma-preserved tendon allografts in group II. Clinical examination revealed a slight increase (P > 0.05) in rectal temperature, heart and respiratory rate for 2-4 days postoperation in both groups. Milder pain and exudation as well as earlier restoration of tendon gliding movements and weight bearing were observed in group I as compared to group II. Air-tendogram in the carbon fibre group on day 30 revealed restoration of continuity across the defect of the tendon. whereas, in the allograft group, a dense homogeneous swelling was seen along the flexors. Regression of peritendinous adhesions and swelling at the reconstructed site at later stages was seen in both groups. Angiography showed hypervascularization at the reconstructed site on day 14 in the carbon fibre group, however, in the allograft group the site appeared to be relatively avascular. On days 30 and 90, blood vessels were normally organized in both groups.     

Novel method for the discrimination of tuna (Thunnus thynnus) and bonito (Sarda sarda) DNA

A novel method for the discrimination of bluefin tuna (Thunnus thynnus) from Atlantic bonito (Sarda sarda) was developed, based on species-specific amplification of a region of the mitochondrial cytochrome b gene by Polymerase Chain Reaction (PCR). The method, which uses a one-step amplification reaction, is more rapid to perform than any of the currently described techniques for species determination in fish. The species of origin of the DNA is indicated by the distinctive size of the PCR product on electrophoresis, but the test could readily be adapted to other forms of electrophoresis or fluorescence-based systems for quantification. Given the possibility of intraspecific variability in mitochondrial DNA and the consequent desirability of performing two independent tests, the new method constitutes a valuable addition to the range of tuna speciation methodologies currently available.     

Radiation treatment for incompletely resected soft-tissue sarcomas in dogs

OBJECTIVE: To evaluate efficacy of radiation for treatment of incompletely resected soft-tissue sarcomas in dogs. DESIGN: Prospective serial study. ANIMALS: 48 dogs with soft-tissue sarcomas. PROCEDURE: Tumors were resected to < 3 cm3 prior to radiation. Tumors were treated on alternate days (three 3-Gy fractions/wk) until 21 fractions had been administered. Cobalt 60 radiation was used for all treatments. RESULTS: Five-year survival rate was 76%, and survival rate was not different among tumor types or locations. Four (8%) dogs developed metastases. Eight (17%) dogs had tumor recurrence after radiation. Development of metastases and local recurrence were significantly associated with reduced survival rate. Median survival time in dogs that developed metastases was 250 days. Median disease-free interval for all dogs was 1,082 days. Median time to recurrence was 700 days. Dogs that developed recurrence after a prolonged period responded well to a second surgery. Acute radiation toxicosis was minimal; osteosarcoma developed at the radiation site in 1 dog. CONCLUSIONS AND CLINICAL RELEVANCE: An excellent long-term survival rate may be achieved by treating soft-tissue sarcomas in dogs with resection followed by radiation. Amputation is not necessary for long-term control of soft-tissue sarcomas in limbs. Development of metastases and recurrence of local tumors after radiation treatment are associated with decreased survival rate. Acute and delayed radiation toxicosis was minimal with the protocol used in this study.     

Differentiation among effects of nitrogen fertilization treatments on conifer seedlings by foliar reflectance: a comparison of methods

Analysis of reflectance can be used to estimate foliar concentrations of photosynthetic pigments, thus providing information on the physiological status of green plants. We compared several methods of reflectance analysis for the capacity to differentiate among effects of fertilization treatments across different irradiances on seedlings of Engelmann spruce (Picea engelmanii Parry ex Engelm.). Seedlings were grown in two light treatments (0 and 60% shade) and three nitrogen (N) treatments (10, 25 and 100 mg N l-1) for one growing season, after which foliar reflectance of the needles was measured. Five indices were tested: R550 (% reflectance at 550 nm); red edge position; the ratio R698:R760; the structure independent pigment index (SIPI); and the photochemical reflectance index (PRI). Both the light and nutrient treatments significantly affected foliar chlorophyll a and b and carotenoid concentrations. Among the indices tested, R550, red edge position and R698:R760 ratio were related to chlorophyll concentration, and were significantly affected by both light and N treatments. Both SIPI and PRI were related to chlorophyll and carotenoid concentrations. Among these relationships, PRI was affected by both treatments, whereas SIPI was sensitive to N treatment but not to light treatment. All five indices were weakly but significantly correlated with growth as measured by dry weight.     

Comparison of cellular schizont, soluble schizont and soluble piroplasm antigens in ELISA for detecting antibodies against Theileria annulata

The efficacy and suitability of cellular schizont, soluble schizont and soluble piroplasm antigens was compared for detecting antibodies against Theileria annulata. Fifty bovine sera of known identity were evaluated in ELISA using the above mentioned antigens. Antibody titres of 1:100 to 1:51,200 were detected while using soluble piroplasm and cellular schizont antigen in ELISA. The titres ranged between 1:100 to 1:25,600 with the soluble schizont antigen. Soluble piroplasm antigen exhibited the highest antibody titres followed by cellular schizont and soluble schizont antigens. Cellular schizont antigen proved to be better than soluble schizont antigen for detecting anti-schizontal antibodies. Antibody titres obtained by the three antigens exhibited a good linear correlation amongst each other. The study showed that soluble piroplasm and cellular schizont antigens can be used successfully for detecting antibodies against piroplasm and schizont stages of T. annulata, respectively in bovine sera.