In vivo lipopolysaccharide injection alters CD4+CD25+ cell properties in chickens

In chickens, thymic CD4(+)CD25(+) cells are characterized as regulatory T cells. The objectives of this experiment were to study the effects of an in vivo lipopolysaccharide (LPS) injection on the percentage of CD4(+)CD25(+) cells in peripheral organs and the suppressive properties of splenic CD4(+)CD25(+) cells in chickens. Chickens were injected with LPS and CD4(+)CD25(+) cells were analyzed at 1, 2, 3, 5, and 10 d post LPS injection. The LPS injection increased CD4(+)CD25(+) cell percentage approximately 5-fold in the blood at 1 d post LPS injection (P < 0.001), 3-fold in the thymus at 3 d post LPS injection (P = 0.001), and 2.5-fold in the spleen at 2 d post LPS injection (P = 0.001) compared with the no-LPS-injected group. The LPS injection did not alter the CD4(+)CD25(+) cell percentage in the cecal tonsil (P = 0.162), lung (P = 0.098), or bone marrow (P = 0.071) at any time point measured. At 2 d post LPS injection, splenic CD4(+)CD25(+) cells lost their suppressive ability (P < 0.001). At 5 d post LPS injection, splenic CD4(+)CD25(+) cells not only regained their suppressive ability, but also became supersuppressive (P < 0.001). Splenic CD4(+)CD25(+) cells at 5 d post LPS injection produced 5.5-fold more (P = 0.005) IL-10 mRNA than splenic CD4(+)CD25(+) cells at 0 and 2 d post LPS injection. In conclusion, chicken regulatory T cells are differentially activated to facilitate immune response during the early stage of inflammation and to facilitate immune suppression at a later stage of inflammation.     

The parasympatholytic effects of atropine sulfate and glycopyrrolate in rats and rabbits.

Nine groups of rats (n = 5 per group) received an intramuscular (IM) injection of one of the following drugs or drug combinations: saline, atropine (0.05 mg/kg), glycopyrrolate (0.5 mg/kg), ketamine:xylazine (85:15 mg/kg), ketamine:detomidine (60:10 mg/kg), atropine:ketamine:xylazine (0.05: 85:15 mg/kg), glycopyrrolate: ketamine:xylazine (0.5:85:15 mg/kg), atropine:ketamine:detomidine (0.05: 60:10 mg/kg) or glycopyrrolate: ketamine:detomidine (0.5:60:10). Similarly six groups of rabbits (n = 5) received an IM injection of either saline, atropine (0.2 mg/kg), atropine (2 mg/kg), glycopyrrolate (0.1 mg/kg), ketamine:xylazine (35:10 mg/kg) or glycopyrrolate:ketamine:xylazine (0.1:35:10 mg/kg). In rats, atropine sulfate (0.05 mg/kg) and glycopyrrolate (0.5 mg/kg) produced an increase in heart rate for 30 and 240 min, respectively. In rabbits atropine sulfate at either 0.2 or 2.0 mg/kg did not induce a significant increase in heart rate, but glycopyrrolate (0.1 mg/kg) elevated the heart rate above saline treated animals for over 50 min. Both atropine and glycopyrrolate provided protection against a decrease in heart rate in rats anesthetized with ketamine: xylazine (85:15 mg/kg) or ketamine: detomidine (60:10 mg/kg); however, glycopyrrolate was significantly more effective in maintaining the heart rate within the normal range. Glycopprrolate also prevented a decrease in heart rate in rabbits anesthetized with ketamine:xylazine (35:5 mg/kg). Neither glycopyrrolate nor atropine influenced respiration rate, core body temperature or systolic blood pressure when used alone or when combined with the injectable anesthetic. Glycopyrrolate is an effective anticholinergic agent in rabbits and rodents and more useful as a preanesthetic agent than atropine sulfate in these animals.     

Monofrequency forced oscillation technique for the investigation of pulmonary function in calves: in vitro and in vivo studies

Parameters derived from the non-invasive and simple monofrequency forced oscillation technique were compared with classical parameters of ventilatory mechanics in order to assess its usefulness for the investigation of pulmonary function in calves. To facilitate this comparison, theoretical derivations were coupled with in vitro measurements, using an artificial lung model, and with in vivo studies. These studies compared the oscillatory resistance parameters (R_os and Re) and the respiratory system compliance (C_rs) against the classical pulmonary resistance (R_L) and the dynamic compliance (C_dyn), respectively. Ros and Re were highly correlated (r0·87) with R_L and the comparison between Crs and C_dyn gave a similarly high correlation (r0·88). Given its simplicity, its correspondence with classical parameters and its rapidity and reproducibility, monofrequency forced oscillation technique seems well suited for the investigation of pulmonary function under field conditions.     

Determination of the alteration in fatty acid profiles, sensory characteristics and carcass traits of swine fed elevated levels of monounsaturated fats in the diet

The present study was designed to determine the effects of supplemental fat or oil rich in oleic acid on the fatty acid profiles (FAP) and physical and sensory traits of pork carcasses. Sixty barrows and gilts were equally distributed among five dietary treatments consisting of a control diet of corn and soybean meal and four similar test diets that contained 10% animal fat (45.3 oleic), safflower oil (72.1 oleic), sunflower oil (80.9 oleic) or canola oil (57.7 oleic). The pigs were slaughtered after being fed these diets for 90 d at about 100 kg live weight. Carcass traits, FAP and sensory properties were evaluated for each treatment. First-rib fat thickness, ham muscling score and longissimus muscle areas were not different (P less than .05), but last-rib fat thickness was increased (P less than .05) with the supplemental dietary fat or oils. No differences existed for marbling scores, lean color, firmness or texture scores between the controls and pigs supplemented with either animal fat or safflower oil. However, pigs supplemented with sunflower or canola oil had lower marbling scores, lean color, firmness and texture scores. Fat became softer and more oily (P less than .05) with the supplemental dietary safflower, sunflower and canola oils. Sensory evaluation (loin chops) showed no differences (P less than .05) in sustained juiciness, tenderness or flavor intensity evaluations among treatments. However, the pigs fed canola oil had lower (P less than .05) flavor quality scores or overall palatability evaluations. Chops from the pigs fed canola oil also had 46% more off-flavors than all other treatments.(ABSTRACT TRUNCATED AT 250 WORDS)     

Cystic thymoma in a cat with cholesterol-rich fluid and an unusual ultrasonographic appearance

A cystic thymoma was identified in an eight-year-old domestic longhair cat with a chronic cough. Radiographs indicated a large mass of soft tissue density in the anterior thorax. Ultrasonography revealed an echogenic mass occupying the cranial and mid-thorax with a slight swirling movement of the echoes. Subsequent drainage under ultrasound guidance yielded a cholesterol-rich fluid. The mass was resected at exploratory thoracotomy and the diagnosis of thymoma confirmed. There was no sign of recurrence one year postoperatively. The clinical features and unusual laboratory findings are presented and compared with previously reported cases of thymomata in the cat.     

Isolation of bovine ovarian inhibin, its immunoneutralization in vitro and immunolocalization in bovine ovary

A purification scheme involving gel permeation chromatography, anion exchange chromatography and reversed-phase high performance liquid chromatography (RP-HPLC) was used to isolate from bovine follicular fluid (FF) biologically-active inhibin of molecular weight 32 kDa. Chromatographic fractions were monitored for inhibin-like biological activity (ILA) using a simplified bioassay procedure in which a suppression of total basal FSH production by rat pituitary cells in monolayer culture indicates the presence of ILA. Approximately 3 mg protein having an ILA potency (ED50 value in in vitro bioassay) of 1.7 ng/ml was obtained from 4 1 crude bovine FF (260 g protein; ILA potency 3750 ng/ml) reflecting an approximate 2200-fold purification factor with an overall recovery of about 3%. The isolated material appeared as a single major UV absorbance peak on RP-HPLC and as a single band (32 kDa) when subjected to SDS-PAGE (15% gel) under non-reducing conditions. Under reducing conditions the molecule dissociated into 2 subunits of apparent molecular weight 22 and 14 kDa confirming that it is probably identical to the 31/32 kDa form of bovine ovarian inhibin previously reported by two other independent research groups. An antiserum raised in a chicken against the isolated material completely neutralized the suppressive effects of both 32 kDa inhibin and bovine FF on basal production of FSH by rat pituitary cells in vitro but only partially reversed the suppressive effects of both porcine and human FF. Immunohistochemical staining of sections of bovine ovary and of isolated preparations of bovine granulosa cells using this antiserum confirmed that granulosa cells are a major source of inhibin. The observation that specific immunostaining was not confined to these cells, however, suggests that they may not be the exclusive source of immunoreactive inhibin in the bovine ovary.     

Effects of hypertonic saline infusion on the adrenocortical response to thiopental-halothane anesthesia in sheep after premedication with acepromazine

OBJECTIVE: To investigate whether hypertonic saline infusion would prevent hypotension and pituitary-adrenocortical axis activation during halothane anesthesia after acepromazine premedication and thiopental induction in sheep. STUDY DESIGN: Randomized crossover study. ANIMALS: Six Welsh Mountain ewes weighing 40+/-2 kg and aged 2 to 3 years. METHODS: The sheep were studied on two occasions with 2 weeks between anesthetics. After acepromazine premedication, anesthesia was induced with thiopental and maintained for 120 minutes with halothane. During the first 15 minutes of anesthesia, 7.5% saline (4 mL/kg) was infused intravenously (HS group), but no infusion was given in the control (CONT) group. Sequential blood samples were taken for blood gas, cortisol, adenocorticotropic hormone (ACTH), glucose, and lactate assay. RESULTS: Hypotension developed in both treatments; blood pressure decreased to a nadir of 58+/-5 mm Hg in the HS group and to 63+/-4 mm Hg in the CONT group (P>.05). Plasma cortisol increased significantly in both groups, reaching a peak of 420+/-130 nmol/L in HS and 483+/-157 nmol/L in CONT (P>.05). ACTH increased similarly in both groups, reaching 128+/-64 pmol/L in HS and 134+/-55 pmol/L in CONT (P>.05). pH was slightly higher in CONT, but no other differences were detected between the two groups. CONCLUSIONS: Hypertonic saline did not ameliorate the adrenocortical response during anesthesia; this may be a result of its failure to prevent the hypotension.     

Immunohistological distributions of fibronectin, tenascin, type I, III and IV collagens, and laminin during tooth development and degeneration in fetuses of minke whale, Balaenoptera acutorostrata.

The immunohistological distributions of fibronectin, tenascin, type I, III and IV collagens, and laminin were observed in the tooth buds of fetuses of minke whale, Balaenoptera acutorostrata. Distributions of extracellular matrices (ECMs) examined in this study except for tenascin were generally similar to those of terrestrial mammalian species during development of the tooth bud. Tenascin in the fetuses of minke whale showed characteristic distributions in the dental lamina and the enamel organ in the early tooth developmental stage. In the physiological degeneration stage of tooth bud development, immunoreactivity of the ECMs were very weakly and limitedly detected in the dental papilla and the surrounding mesenchyme. Immunoreactivity of tenascin and type I and III collagens were positively detected in the developing baleen plate germ which was associated with the degenerating tooth bud. These findings suggested that expressions of the ECMs were related to the formation of the tooth bud and baleen plate germ, and that the lack of the ECMs was related to the degeneration of the tooth bud in the fetal minke whale.