Hematological and clinical responses to combined mitoxantrone and cyclophosphamide administration to normal cats.

The purpose of this study was to examine the feasibility of a combination chemotherapy protocol ("CYCLONE") in cats, utilizing mitoxantrone and cyclophosphamide. Three normal adult cats were administered mitoxantrone (6.5 mg/m2 intravenously) and cyclophosphamide (100 mg/m2 intravenously) every 21 days for a total of three doses. Individual white blood cell count nadirs (range, 2.0-9.5 x 10(9)/L) and neutrophil count nadirs (range, 0.3 to 5.0 x 10(9)/L) occurred between days 2 and 10 after each dose of chemotherapy. Mean white blood cell count nadirs (range of mean, 5.5 to 8.4 x 10(9)/L) occurred between days 6 and 8, as did the mean neutrophil count nadir (range of mean, 1.7-4.0 x 10(9)/L). Side effects were limited to transient appetite suppression in one cat and loose stools in two cats. Myelosuppression and gastrointestinal side effects were comparable to those observed with single-agent mitoxantrone protocols. Further investigation of this protocol is warranted.     

Long-term cattle gain responses to stocking rate and grazing systems in northern mixed-grass prairie

The effects of stocking rate and grazing system on gains of yearling beef cattle grazing rangelands have largely been addressed in short-term (< 10 years) studies, and often stocking rates are confounded within grazing systems with higher stocking rates for short-duration rotational grazing systems compared to season-long grazing. A grazing system (season-long and short-duration rotational grazing) × stocking rate (light: 16 steers/80 ha, 18.0 animal unit days/ha; moderate: 4 steers/12 ha, 30.1 animal unit days/ha; and heavy: 4 steers/9 ha, 40.1 animal unit days/ha) study was initiated in 1982 on northern mixed-grass prairie. Here, we report on the final 16 years (1991–2006) for yearling beef cattle gains. Average daily gains (kg/head/day) across all years with season-long grazing decreased with increasing stocking rate and grazing pressure. Heavy stocking rates reduced average daily gain by 16% and 12% compared to light and moderate stocking rates, respectively. In contrast to average daily gain, beef production (kg/ha) increased with increasing stocking rate and grazing pressure. Cattle gains were reduced by 6% with short-duration rotation compared to season-long grazing over the study period, with differences between systems observed in years with average, but not dry or wet, spring (April + May + June) precipitation. Grazing season gains (kg/head) and beef production both exhibited significant increasing hyperbolic relationships with spring precipitation, with the percentage of variation explained by spring precipitation substantially higher (62–83%) for beef production compared to grazing season gains (32–45%). The influence of spring precipitation on cattle gains suggests that incorporation of these relationships into modeling efforts for strategic planning and risk assessment will assist land managers in better matching forage and animal resources for greater sustainability in this highly variable environment.     

Effect of humic acids on intestinal viscosity,leaky gut and ammonia excretion in a 24 hr feed restriction model to induce intestinal permeability in broiler chickens

The purpose of this study was to evaluate the effect of humic acids (HA) on intestinal viscosity, leaky gut and ammonia excretion in a 24 hr feed restriction (FR) model to induce intestinal permeability in chickens. One‐day‐old male Cobb‐Vantress broilers were randomly allocated to one of two groups (n = 25 chickens), with or without 0.2% of isolated HA from worm‐compost, and placed in brooder batteries. Chicks had ad libitum access to water and feed for 14 days. Intestinal permeability was induced by 24 hr FR starting at 14 days. At 15 days of age, chickens in both groups were given an appropriate dose of fluorescein isothiocyanate dextran (FITC‐d) by oral gavage. Intestine and liver samples were also collected to evaluate viscosity and bacterial translocation (BT), respectively. An increase (p < .05) in intestinal viscosity was observed in the experimental group consuming 0.2% of HA and was confirmed in a published in vitro digestion model that simulates the chemical and physical conditions of the crop, proventriculus and intestine of chickens. Furthermore, the treated group also showed a significant reduction in FITC‐d, liver BT and ammonia in the manure. These results suggest that HA have a positive impact in intestinal integrity in chickens.     

Comparison of available soil water capacity estimated from topography and soil series information

We present a simple and generalized method to predict Available Soil Water Capacity (ASWC-TOP) for a given area using a topographic index, defined as ln(/tan), where is the upslope area draining past a certain point per unit width of slope, and is the local surface slope angle. The estimated results (ASWC-TOP) were then compared with the available soil water capacity calculated from soil series information provided by Soil Conservation Service, U.S. Department of Agriculture (ASWC-SCS). The model implementation was tested with three study cases: the Seeley-Swan valley, Montana, with pixel resolutions of 100 m and 1 km, respectively; and the state of Montana, U.S.A., with a pixel resolution of 1 km. A linear relationship exists between ASWC-SCS and ln(/tan). Standard errors between ASWC-TOP and ASWC-SCS were about 4.4 cm in the Seeley-Swan valley and 5.5 cm in the state. The number of pixels with absolute residuals 4 cm between ASWC-TOP and ASWC-SCS accounted for 68.2, 64.4, and 51.9% for the valley 100 m, valley 1 km, and the state respectively. Some of the mismatches between ASWC-TOP and ASWC-SCS may indicate an improvement using this method compared to existing data because the topographic method reflects the higher spatial variation of the inputs. The increasing availability of digital elevation data, at various resolutions, may provide an alternative to soil series for estimating ASWC. The accuracy of ASWC-TOP depends on estimation of mean and maximum ASWC for a study area.     

In vitro effects of plant essential oils on non‐specific immune parameters of red drum,Sciaenops ocellatus L.

Phytochemicals such as plant essential oils (EOs) have been reported to favour various activities in the innate immune system of fish. Thus, the aim of this study was to verify the in vitro effect of three different plant EOs (Ocimum americanum, Cymbopogon flexuosus and Melaleuca alternifolia) on non‐specific immune parameters and erythrocyte osmotic fragility of red drum, Sciaenops ocellatus. Concentrations of each plant EO evaluated in preparations of head‐kidney macrophages, blood leucocytes and blood plasma were as follows: 0.0 (control), 1.0, 2.0, 4.0, 8.0, and 16.0 μg/ml. Red drum head‐kidney macrophages significantly increased extracellular superoxide anion production when exposed (20 h) to O. americanum EO (1.0‐8.0 μg/ml) and C. flexuosus EO (2.0 and 4.0 μg/ml). The respiratory burst of blood leucocytes (NBT test) significantly increased in all concentrations when compared to the respective control group, for all EOs. At the highest concentration (16.0 μg/ml), C. flexuosus EO significantly inhibited the haemolytic activity of complement system in red drum blood after 1 h exposure. None of the tested concentrations significantly altered plasma lysozyme activity or erythrocyte osmotic fragility after exposing (1 h) red drum whole blood to each EO. This study demonstrated that these plant EOs are capable of triggering superoxide anion production in red drum leucocytes (head‐kidney macrophages and/or blood leucocytes). In vivo studies are warranted to address their potential as immunostimulants in the diet of red drum and other aquacultured species.     

Effect of a pelleted supplement fed during and after omeprazole treatment on nonglandular gastric ulcer scores and gastric juice pH in horses

Gastric ulcers are common in horses. The purpose of this study was to test the effect of a commercially available supplement, SmartGut^® Ultra pellets (SmGU) on gastric ulcer scores and gastric juice pH after omeprazole treatment in stall‐confined horses. Eight Thoroughbred horses were studied in a 2‐period, 2‐treatment crossover design, where the SmGU (40 g, twice daily) was mixed in grain feed. Horses were stall‐confined and treated with the supplement or control for 6 weeks, consisting of 2 weeks (Days 1–14) omeprazole treatment, 2 weeks (Days 14–28) following discontinuation of omeprazole treatment, one week (Days 28–35) alternating feed deprivation to induce or worsen existing ulcers and a one week (Days 35–42) recovery period. Gastroscopy was performed and gastric juice pH measured on Days 0, 14, 28, 35 and 42. Gastric ulcer lesion number (NGN) and severity (NGS) scores were assigned to each horse by an investigator (F.M.A.) masked to treatment. On Day 0 before treatment, mean NGN and NGS scores and gastric juice pH were not different (P>0.05) between treatment groups. By Day 14, mean NGN and NGS scores decreased (P<0.05) in both treatment groups. By Days 28 and 35, mean NGN score significantly increased in the untreated control horses but not the SmGU‐treated horses. By Day 42, mean NGN and NGS scores were not different in either group and were significantly lower than Day 0. Mean gastric juice pH was higher in both groups on Day 14 as a result of omeprazole treatment when compared with other days. SmartGut^® Ultra supplement added to the feed prevented the worsening of gastric ulcer number 2 weeks after omeprazole treatment, without altering the gastric juice pH. Supplementation with SmGU might aid in protection of the nonglandular stomach from recurrence of ulcers after omeprazole treatment in stall‐confined horses undergoing intermittent feeding.