Entamoeba infections in different populations of dogs in an endemic area of Lahore,Pakistan

Entamoeba histolytica, a protozoan parasite that affects humans and other primates all over the world. It is a common waterborne pathogen in endemic areas that have fecal oral transmission cycle. The aim of the present study was to examine the prevalence of E. histolytica and other Entamoeba species cysts in three different dog populations. Fecal samples from 600 dogs were collected and processed to detect Entamoeba cysts using the triple fecal test (light microscopy) and fecal antigens of E. histolytica were detected using a fecal antigen ELISA (TechLab E. histolytica II). Because it is impossible to differentiate E. histolytica from Entamoeba dispar and E. moshkovskii, using light microscopy we referred to all cysts morphologically consistent with E. histolytica as E. histolytica/dispar/moskovskii to reflect this uncertainty. Samples from 197 household dogs without clinical signs, 122 samples from household dogs exhibiting clinical signs of diarrhea, dysentery and vomiting and 281 stray dogs with no specific clinical signs were examined. Entamoeba histolytica-like cysts were observed in 94 (15.6%, 95% CI = ±3.88) by triple fecal test microscopy and E. histolytica antigens were demonstrated in 66 (11%, 95% CI = ±4.41) by fecal antigen ELISA in 600 fecal samples. Significant differences (P ≤ 0.05) in prevalence were found between the three populations. Twenty (10.1%, 95% CI = ±7.86) and 11 (5.6%, 95% CI = ±7.70) of 197 fecal samples from household dogs without clinical signs were positive by microscopy and by antigen ELISA, respectively. Twenty-nine (23.8%, 95% CI = ±6.58) and 23 (18.8%, 95% CI = ±7.81) of 122 the fecal samples from household dogs with clinical signs were positive by microscopy and by antigen ELISA, respectively. Forty-five (16.01%, 95% CI = ±5.62) and 32 (11.3%, 95% CI = ±6.38) of 281 fecal samples from stray dogs were positive by microscopy and by fecal antigen ELISA, respectively. Dogs from the youngest age group (6 months to 1 year) were more likely to be E. histolytica antigen positive than were dogs from the other two older age groups, with a significant difference (P ≤ 0.05) between all age groups. Statistically, no significant (P ≥ 0.05) difference of prevalence was seen in male and female dogs. The local dogs had the highest prevalence rate of E. histolytica antigens (36 of 246, 14.2%, 95% CI = ±6.32) followed by imported breeds (11 of 115, 9.5%, 95% CI = ±10.4) and crossbred (19 of 239, 8.3%, 95% CI = ±7.47), indicating a significant (P ≤ 0.05) trend of positivity between various breeds of dogs. These findings suggest that dogs may play an important role in the epidemiology of this pathogen.     

Effects of inoculum size on cell-mediated and humoral immune responses of foals experimentally infected with Rhodococcus equi: A pilot study

The objective of this pilot study was to compare the cytokine profile as well as cell-mediated and antibody responses of foals infected with a low inoculum of virulent Rhodococcus equi resulting in subclinical pneumonia to that of foals infected with a high inoculum resulting in severe clinical pneumonia. The mean (±SD) ratio of post-infection to pre-infection anti-R. equi IgG(T) concentration was significantly (P = 0.002) higher in foals infected with the high inoculum (195 ± 145; range 62–328) compared to foals infected with the low inoculum (3.9 ± 4.5; range 0.5–11). Similarly, mean (±SD) ratio of post-infection to pre-infection IgM concentration was significantly (P = 0.002) higher in foals infected with the high inoculum (12 ± 4.0; range 7.4–14) compared to foals infected with the low inoculum (2.5 ± 1.5; range 1.2–4.7). Proliferative responses to R. equi antigens as well as expression of mRNA for IL-2, IL-4, IL-10, and IFN-γ in BLN were not significantly different between the two groups. There was a tendency (P = 0.073) towards a higher IFN-γ/IL-4 ratio in the low inoculum group. This study demonstrates that the size of inoculum modulates the IgG subisotype response and possibly the cytokine profile of foals.     

Preference among 7 bait flavors delivered to domestic dogs in Arizona: Implications for oral rabies vaccination on the Navajo Nation

Less than 20% of the domestic dogs on tribal lands in the United States are vaccinated against rabies. One method to increase vaccination rates may be the distribution of oral rabies vaccines (ORVs). ONRAB^® (Artemis Technologies, Inc., Ontario, Canada) is the primary ORV used in Canada to vaccinate striped skunks and raccoons. To investigate the potential use of ONRAB^® ORV baits to vaccinate feral domestic dogs against rabies on tribal lands and beyond, we performed a flavor preference study. A total of 7 bait flavors (bacon, cheese, dog food, hazelnut, sugar-vanilla, peanut butter, and sardine) were offered in pairs to 13 domestic dogs. Each dog was offered all possible combinations of bait pairs over a period of 10 days, with each bait offered 6 times. The proportion of times each bait was consumed first by individual dogs was calculated and comparisons among dogs were conducted using the MIXED procedure in SAS (SAS Institute, Cary, NC). Pairwise comparisons between baits were performed using “contrast” statements with sugar-vanilla flavor as the default for comparison. Type 3 tests of fixed effects showed a significant treatment effect (F_6,72 = 9.74, P < 0.0001). Sugar-vanilla was selected first during 14% of the offerings and exhibited the least preference among all bait types (F_1,72 = 22.46, P < 0.0001). Dog food was selected first 56% of the time, and more frequently than all other bait types (F_1,72 = 13.09, P = 0.0005).     

Variability of scores in the 2008 Olympic dressage competition and implications for horse training and welfare

Olympic dressage involves “an intimate unity between a human and a non-human” and is scored by a subjective judging process, under the auspices of the Fédération Equestre Internationale whose Code of Conduct declares the welfare of the horse as paramount. Dressage is of particular interest to equitation scientists and equine ethologists because it embodies the full range of the stimulus-response contingencies that operate in all of the Olympic disciplines. In Fédération Equestre Internationale dressage competition, collective marks are awarded across four domains immediately after each performance. Collective marks are designed to summarize the performance of horse and rider and must reflect the qualities of the entire performance. They are derived from the observation of the judges of the separate test movements. The 4 collective marks include: (1) paces; (2) impulsion; (3) submission; and (4) the rider's position and seat; correctness and effect of the aids (rider signals). The definition of submission in this context makes reference to lightness and other qualities that align with optimal ridden horse welfare. We assessed the characteristics of these marks in horses competing in the 2008 Olympic Games Grand Prix (GP; n = 46) and Grand Prix Special (GPS; n = 25) dressage competitions. We also examined the effect of judge location and used Pearson correlation coefficients to explore relationships between collective marks and test-movement scores. All 4 collective marks correlated with each other significantly (P < 0.001). The weakest correlation was between paces and submission (r = 0.22) and the strongest between impulsion and rider position scores (RPS) (r = 0.59). In the GP, paces and submission scores were less correlated with test movement scores than the impulsion and RPS scores. In the GPS, submission scores were less correlated with individual movements than the other collective marks. Indeed, they failed to significantly correlate with 19 of 32 movement scores (P < 0.05). RPS varied most in the GP (standard deviation = 0.73) whereas submission scores varied most in the GPS (standard deviation = 0.65). A REML analysis across both competitions showed all collective marks were significant in predicting final percentage scores but submission (F = 31.27) made the least significant contribution (paces, F = 61.3; impulsion, F = 69.77; RPS F = 53.01; P < 0.001 for all values). These results speak of considerable variability in judging and suggest that, despite the relevance of submission to horse welfare, judges have considerable difficulty scoring in this domain and aligning their scores with overall performance.     

Effects of trilostane on the pituitary-adrenocortical and renin–aldosterone axis in dogs with pituitary-dependent hypercortisolism

The medical records of 63 dogs with pituitary-dependent hypercortisolism (PDH) before and during treatment with trilostane were reviewed retrospectively. The correct trilostane dosage in dogs with PDH was based on the resolution of clinical signs and the results of an adrenocorticotropic hormone (ACTH) stimulation test. The mean (±SD) dose rate of trilostane to achieve good clinical control was 2.8 ± 1.0 mg/kg bodyweight. Trilostane treatment resulted in a significant decline in basal plasma cortisol concentrations. The median plasma ACTH concentration (39 pmol/L, range 7–132 pmol/L; n = 60) at the optimal trilostane dosage time was significantly higher (P < 0.001) than before treatment (13 pmol/L, range 2–102 pmol/L). These values did not overlap with plasma ACTH concentrations (range 212–307 pmol/L) of five PDH dogs with trilostane-induced hypocortisolism.The median cortisol/ACTH ratio in well-controlled dogs (0.23, range 0.03–2.5; n = 46) was significantly lower (P < 0.001) than before treatment (2.59, range 0.27–13.25). Trilostane treatment resulted in an insignificant decrease in plasma aldosterone concentration (PAC), but the median plasma renin activity (PRA) at the time the trilostane dosage was considered optimal (265 fmol/L/s, range 70–3280 fmol/L/s; n = 18) was significantly higher (P < 0.001) than prior to treatment (115 fmol/L/s, range 15–1330 fmol/L/s). Similarly, the median PAC/PRA ratio during trilostane treatment (0.16, range 0.003–0.92; n = 17) was significantly lower (P < 0.001) than before treatment (median 0.44, range 0.04–1.33). Trilostane affected both the hypothalamic-pituitary-adrenocortical and the renin–aldosterone axes. The results also suggested that basal plasma ACTH concentration may be used to detect trilostane overdosage.     

A prospective study on fitness,workload and reasons for premature training ends and temporary training breaks in two groups of riding horses

Little is known about wastage in riding horses and the factors like fitness and workload that may reduce injuries and maximise welfare. To evaluate fitness, workload and reasons for premature training ends (PTEs) and temporary training breaks (TTBs) during a nine week training period, two groups of riding horses were used: Group A consisting of 58 horses used for student equitation courses (32 with training prior to admission and 26 without) and Group B consisting of 26 horses owned by two riding schools (school-I and school-II). To assess fitness, all horses performed a standardised exercise test (SET) at the start (SET-I) and end of the training period (SET-II) measuring heart rate (HR bpm) and speed (m/s). In addition, all horses were monitored daily during the training period for their health and workload.In Group A, trained horses had significantly lower HRs in SET-I (P = 0.05) compared to untrained horses and in SET-II, trained horses tended to have lower HRs than untrained horses, though this was not statistically significant (P = 0.057). During the training period all horses received an identical workload. A total of 19.0% of Group A horses ended the training period prematurely for veterinary reasons (PTEV); of those untrained horses had earlier a PTEV in the training period (after 2.8 ± 1.3 weeks) than trained horses (after 4.1 ± 1.5 weeks, P = 0.030).In Group B, school-I and school-II horses did not differ significantly in fitness level nor in workload. More school-II horses ended the training period prematurely for veterinary reasons (n = 7; 70%) compared to school-I horses (n = 4; 25%, P = 0.032), although seven (63.6%) of these horses were still continuously used in riding lessons. In both groups (A and B), small injuries (without a temporary training break) were significantly associated with premature training ends for veterinary reasons later on: in Group A small injuries preceded 27.3% of the PTEVs (P = 0.005) and in Group B small injuries preceded 54.5% of the PTEVs (P = 0.030).In conclusion, as all horses in each subgroup had the same workload, the occurrence of PTEV seemed not associated with the workload. In Group A horses, level of fitness seems to be an important factor for the point in time injuries will occur during the training period. In all horses, injuries were more likely when a temporary training break was not taken following seemingly minor injuries. Since a lot of injured Group B horses were used in riding lessons against veterinary advice, this may indicate that riding school owners have different perception on welfare and if true this may cause serious welfare problems.     

Serum biochemical parameters and embryo production during superovulatory treatment in dairy cattle

The objective of this study was to determine the relationship between the number of transferable embryos (TE) and various blood chemistry parameters as a reflection of the metabolic state of cows after superovulatory treatment. Forty-nine Holstein cows were subjected to superovulatory treatment for commercial embryo production. At the time of embryo harvest, individual blood samples were taken from cows for biochemical analysis. All embryos including dead ones as well as non-fertilized oocytes were counted in uterine lavage. Feed samples collected daily for a period of two weeks before embryo harvest, were analyzed for mycotoxins: vomitoxin, zearalenone and T-2 toxin. On average, cows produced 9.45 ± 5.60 embryos and oocytes of which 5.27 ± 4.20 were TE, 0.37 ± 0.80 were dead embryos and 3.82 ± 3.78 were non-fertilized oocytes. Higher concentrations of Mg and K were associated with a higher production of TE (p = 0.005 and p = 0.043, respectively) and higher activity of creatinine kinase was associated with a lower production of TE (p = 0.011).     

Foraging of Iberian fattening pigs grazing natural pasture in the dehesa

Two different herds of Iberian pigs have been studied in the montanera fattening period (from November first to end of December) in the dehesa agrosystem (clear forest of evergreen oaks, Quercus rotundifolia) during two different autumns and winters (2003 and 2004) without any supplementary feed. A direct in situ observation method has been used, with continuous observation of ingestive bites taken by continuously monitored pigs (10 uninterrupted hours, from 08:30 to 18:30) to calculate intake. 95 grazing days have been studied corresponding to different randomly chosen pigs. The obtained results show grass and acorns as the main resources with 56.5 and 43.3% of bites respectively. 14 other resources different from grass and acorns were registered, but only 9 resources (berries, bushes, inorganic rubbish, woods, roots, earth and sand, charcoal and ashes, carrion and straw) were consumed at a frequency ≥ 0.01%. The percentage distribution for daily bites showed no significant difference between years. However daily grazing times were significantly affected by year, and were associated with available drinking water from rain. Lack of water in second montanera forced pigs to return to shelters to drink and, in consequence, reduced daily mean grazing time (from 427 ± 14 min in montanera 1 to 368 ± 8 in montanera 2; P < 0.001) and kernel acorn dry matter intake (from 3.6 ± 0.3 kg in montanera 1 to 3.1 ± 0.1 in montanera 2; P < 0.05); however, it did not significantly influence either daily grass dry matter intake (0.38 ± 0.04 kg in montanera 1 versus 0.49 ± 0.04 kg in montanera 2) or total daily dry matter intake calculated from bite number (4.0 ± 0.3 kg in montanera 1 versus 3.6 ± 0.1 in montanera 2).     

Effects of single or trickle Haemonchus contortus experimental infection on digestibility and host responses of naïve Creole kids reared indoor

The objective of this study was to compare the effects of the type of Haemonchus contortus experimental infection (trickle infection, TI versus single infection, SI) on feed intake, nutrients digestibility, parasitological and haematological measures, and plasma leptin in Creole kids. The animals were infected over 2 periods (challenge 1 and challenge 2) of 6 weeks each, corresponding respectively to the primary and the secondary infection. Periods prior infection (1 week each) were considered as controls. The primary infection was realized with 35 Creole kids (18.40 ± 3.76 kg BW) housed in individual boxes and fed a hay-based diet. The secondary infection continued with 29 kids (21.90 ± 3.40 kg BW) from the initial 35. A total of 6 kids and 8 kids were slaughtered for measuring nematode burden at the end of the primary and the secondary infection, respectively. Measurements of nutrients digestibility were made at 0, 3 and 5 weeks post-infection for both challenges. Faecal egg count (FEC), blood eosinophilia and packed cell volume (PCV) were monitored weekly. Feed intake (dry matter intake, DMI) and nutrients digestibility were negatively affected by H. contortus infection only during the primary infection. Plasma leptin changed significantly over time (P = 0.0002) but was not affected by the infection type. Effect of infection type was observed only on crude protein digestibility during the primary infection, which was lower in the TI group (P < 0.01). The overall level of blood eosinophilia was significantly higher in the TI group (P < 0.0001) during both challenges. The overall FEC mean was significantly higher in the SI compared with the TI groups, during both challenges (P < 0.02). These results were related to the mean female length significantly higher in the SI group compared with the TI group during challenge 1 (P = 0.004), and the number of adult nematode significantly lower in the TI group compared with the SI group during the challenge 2 (P = 0.05). The results showed that the response of Creole kids to H. contortus experimental infection was in part dependent on the type of experimental infection. Our data suggest that plasma leptin would not be involved in the response of Creole kids against H. contortus infection, as no relationship between its plasma level and the transient reduction in voluntary feed intake observed in both groups during the primary infection was observed.     

Interannual Herbaceous Biomass Response to Increasing Honey Mesquite Cover on Two Soils

This study quantified herbaceous biomass responses to increases in honey mesquite (Prosopis glandulosa Torr.) cover on two soils from 1995 to 2001 in north central Texas. Vegetation was sampled randomly with levels of mesquite ranging from 0% to 100%. With no mesquite covering the silt loam soils of bottomland sites, peak herbaceous biomass averaged (±SE) 3 300 ± 210 kg · ha⁻¹ vs. 2 560 ± 190 kg · ha⁻¹ on clay loam soils of upland sites (P = 0.001). A linear decline of 14 ± 2.5 kg · ha⁻¹ in herbaceous biomass occurred for each percent increase in mesquite cover (P = 0.001). The slope of this decline was similar between soils (P = 0.135). Herbaceous biomass with increasing mesquite cover varied between years (P = 0.001) as did the slope of decline (P = 0.001). Warm-season herbaceous biomass decreased linearly with increasing mesquite cover averaging a 73 ± 15% reduction at 100% mesquite cover (P = 0.001) compared to 0% mesquite cover. Cool-season herbaceous biomass was similar between soils with no mesquite, 1 070 ± 144 kg · ha⁻¹ for silt loam vs. 930 ± 140 kg · ha⁻¹ for clay loam soils, but averaged 340 ± 174 kg · ha⁻¹ more on silt loam than on clay loam soils at 100% mesquite cover (P = 0.004). Multiple regression analysis indicated that each centimeter of precipitation received from the previous October through the current September produced herbaceous biomass of 51 kg · ha⁻¹ on silt loam and 41 kg · ha⁻¹ on clay loam soils. Herbaceous biomass decreased proportionally with increasing mesquite cover up to 29 kg · ha⁻¹ at 100% mesquite cover for each centimeter of precipitation received from January through September. Increasing mesquite cover reduces livestock forage productivity and intensifies drought effects by increasing annual herbaceous biomass variability. From a forage production perspective there is little advantage to having mesquite present.     

The impact of dystocia on dairy calf health,welfare, performance and survival

Up to one-third of dairy calves are born after dystocia and this is a major cause of calf mortality. This study investigated the neonatal physiology, survival, health and subsequent growth of dairy calves following dystocia and is the first longitudinal study to analyse multiple effects and to look beyond the perinatal period.A total of 455 live born Holstein calves (N: No assistance, n = 360; FN: Farmer assistance but normally presented calf, n = 82; FM: Farmer assistance of malpresented calf, n = 13) were followed from birth to first service (heifers) or until leaving the farm (bulls). Compared to N calves, FN and FM animals had higher salivary cortisol concentrations at day 1 (P < 0.001) and FN calves had lower passive immune transfer (P = 0.03). Dystocia had no biologically significant impact on rectal temperature throughout the first 4 days (P > 0.05). During the first 60 days, FM calves had a higher proportion of days with non-routine health treatments (P < 0.05) and, by the time of weaning, mortality in FN and FM heifers was higher than in N calves (2.8×; P < 0.01). However, in surviving calves, growth to first service was not affected by dystocia category (P > 0.05).Calves which survive dystocia experience lower passive immunity transfer, higher mortality and higher indicators of physiological stress. Such calves have poorer welfare in the neonatal period and possibly beyond. Strategies need to be implemented to improve the subsequent health and welfare of such calves and to lower the incidence of dystocia.     

Grade is an independent prognostic factor for feline mammary carcinomas: A clinicopathological and survival analysis

Feline mammary carcinomas (FMC) are highly infiltrative tumours which show a strong tendency for local recurrence and metastasis. Histological type assessment of these tumours is not sufficiently discriminatory in predicting prognosis and in this study the prognostic significance of the Elston and Ellis method of histological grading was evaluated. Ninety-two feline mammary carcinomas from 84 cats were graded and 64 queens were included in a follow-up study.Grade was significantly related to tumour size (P = 0.006), clinical stage (P = 0.005), lymphovascular invasion (P < 0.0001), mitotic index (P < 0.0001), Ki67 index (P = 0.001), overall survival (P = 0.0001) and disease-free survival (P < 0.0001). Cox regression analysis identified grade as an independent prognostic factor. Multivariable analysis also showed regional lymph node metastasis and lymphovascular emboli as independent prognostic factors related to overall survival and to disease-free-survival, respectively. The study demonstrated that histological grading can be used as a prognostic factor to evaluate the biological behaviour of FMC.     

Pharmacokinetics of erythromycin after intravenous,intramuscular and oral administration to cats

The aim of this study was to characterise the pharmacokinetic properties of different formulations of erythromycin in cats. Erythromycin was administered as lactobionate (4 mg/kg intravenously (IV)), base (10 mg/kg, intramuscularly (IM)) and ethylsuccinate tablets or suspension (15 mg/kg orally (PO)). After IV administration, the major pharmacokinetic parameters were (mean ± SD): area under the curve (AUC)_(0–∞) 2.61 ± 1.52 μg h/mL; volume of distribution (V_z) 2.34 ± 1.76 L/kg; total body clearance (Cl_t) 2.10 ± 1.37 L/h kg; elimination half-life (t_½λ) 0.75 ± 0.09 h and mean residence time (MRT) 0.88 ± 0.13 h. After IM administration, the principal pharmacokinetic parameters were (mean ± DS): peak concentration (C_max), 3.54 ± 2.16 μg/mL; time of peak (T_max), 1.22 ± 0.67 h; t_½λ, 1.94 ± 0.21 h and MRT, 3.50 ± 0.82 h. The administration of erythromycin ethylsuccinate (tablets and suspension) did not result in measurable serum concentrations. After IM and IV administrations, erythromycin serum concentrations were above minimum inhibitory concentration (MIC)₉₀ = 0.5 μg/mL for 7 and 1.5 h, respectively. However, these results should be interpreted cautiously since tissue erythromycin concentrations have not been measured and can reach much higher concentrations than in blood, which may be associated with enhanced clinical efficacy.     

Age and Body Condition of Goats Influence Consumption of Juniper and Monoterpene-Treated Feed

Redberry juniper (Juniperus pinchotii Sudworth) is an invasive, evergreen tree that is rapidly expanding throughout western and central Texas. Goats will consume some juniper on rangelands; however, intake is limited. The objective of our research was to determine how the age and body condition of goats influence their consumption of juniper and an artificial feed containing 4 monoterpenes. Two separate experiments were conducted. Experiment 1 examined the intake of redberry juniper foliage and used 39 goats either young (2 yr) or mature (> 6 yr). One-half of each age group was fed appropriate basal rations to reach either a high (HBC) or low body condition (LBC). Goats in LBC ate more (P < 0.01, 8.6 g · kg⁻¹ body weight [BW] ± 0.7 SE) juniper than those in HBC (2.3 g · kg⁻¹ BW ± 0.3 SE), and young animals consumed more (P < 0.05, 7.2 g · kg⁻¹ BW ± 0.7 SE) juniper than mature goats (3.9 g · kg⁻¹ BW ± 0.5 SE) across body condition treatments. In experiment 2, 36 goats, either young (2 yr) or mature (> 6 yr) and in either HBC or LBC, were offered a synthetic ration treated with 20.8 g · kg⁻¹ of 4 monoterpenes found in redberry juniper. Goats in LBC ate more (P < 0.01, 25.3 g · kg⁻¹ BW ± 1.0 SE) of the terpene-treated feed than those in HBC (17.5 g · kg⁻¹ BW ± 0.7 SE), and young animals ate more (P < 0.05, 22.5 g · kg⁻¹ BW ± 0.8 SE) than mature goats (20.3 g · kg⁻¹ BW ± 0.8 SE) across body condition treatments. Total intake as a proportion of body weight was also affected by body condition. Age and body condition are important factors that influence intake of chemically defended plants. A better understanding of how these attributes affect diet selection will aid livestock producers in improving grazing management.     

Pharmacokinetics,plasma protein binding and bioavailability of moxifloxacin in Muscovy ducks after different routes of administration

In this study the disposition kinetics and plasma availability of moxifloxacin in Muscovy ducks after single intravenous (i.v.), intramuscular (i.m.) and oral (p.o.) administrations of 5 mg kg^?1 b.wt. were investigated. The concentrations of moxifloxacin in the plasma were measured using high-performance liquid chromatography (HPLC) with fluorescence detection on samples collected at frequent intervals after drug administration. Following intravenous injection, the decline in plasma drug concentration was bi-exponential with half-lives of (t_1/2α) 0.22 ± 0.10 h and (t_1/2β) 2.49 ± 0.26 h for distribution and elimination phases, respectively. The volume of distribution at steady-state (V_dss) was 1.02 ± 0.14 l kg^?1 and the total body clearance (Cl_tot) was 0.32 ± 0.11 l kg^?1 h^?1, respectively. After intramuscular and oral administration of moxifloxacin at the same dose the peak plasma concentrations (C_max) were 2.38 ± 0.43 and 2.11 ± 0.36 μg ml^?1 and were obtained at 1.47 ± 0.26 and 1.83 ± 0.16 h (T_max), respectively, the elimination half-lives (T_1/2el) were 3.14 ± 0.42 and 2.63 ± 0.44 h, respectively, and AUC_0–24 were 15.87 ± 2.35 and 14.52 ± 2.37 μg ml^?1 h^?1, respectively. The systemic bioavailabilities were 96.36 ± 11.54% and 86.79 ± 12.64%, respectively. In vitro plasma protein binding percent was 32%. We concluded that moxifloxacin might be clinically interesting alternative for the treatment of most sensitive bacterial infections in Muscovy ducks.     

Comparative pharmacokinetics of an injectable cephalexin suspension in beef cattle

This study describes and compares the pharmacokinetics of a single 7.5 mg/kg dose of cephalexin monohydrate oil-based 20% suspension after its administrations to six cows by the intramuscular (i.m.) and subcutaneous (s.c.) routes, and to five calves by the i.m. route. Significantly (P < 0.05) higher peak plasma concentrations (5.6 ± 0.79 μg/ml versus 3.93 ± 1.24 μg/ml) and lower half-life (1.81 ± 0.56 h versus 4.21 ± 0.82 h) and mean residence time (4.12 ± 1.07 h versus 6.63 ± 0.85 h) were obtained after i.m. administration when compared to the s.c. administration to cows. No differences were found between pharmacokinetic parameters calculated for cows and calves. Cephalexin plasma concentrations remained above 0.5–0.75 μg/ml for 11–14 h and 8–9 h after the s.c. and i.m. administrations, respectively. Thus, route of administration may be an important issue to be considered when calculating dosage schedules for successful treatments and safe withdrawal times for veterinary medicines.     

Airway hyperresponsiveness to adenosine 5’-monophosphate in feline chronic inflammatory lower airway disease

Airway hyperresponsiveness is a key feature of human asthma and chronic bronchitis and response to the indirectly acting agonist adenosine 5′-monophosphate (AMP) is thought to reflect underlying airway inflammation. To examine whether airway responsiveness testing (ART) with AMP may be used to differentiate healthy cats from those with asthma (FA) and chronic bronchitis (CB), 24 cats (9 FA, 6 CB, 9 controls) underwent ART with AMP at concentrations of 0.1, 1, 10, 100 and 500 mg/mL using barometric whole body plethysmography.The defined endpoint of ART, an increase in enhanced pause (Penh) exceeding 300% of the post-saline value (baseline), was reached in 9/15 patients (7 FA, 2 CB), but in none of the controls. Mean Penh (±SD) at baseline (BL) was 0.49 ± 0.16 for cases, and 0.54 ± 0.16 for controls, and was significantly increased after AMP challenge in clinical cases (2.62 ± 2.20), but not in controls (0.63 ± 0.30, P < 0.05). After separating responder (R) and non-responder (NR) cases, a more pronounced difference after challenge was found (R: 3.96 ± 1.84, NR: 0.6 ± 0.21, P < 0.001). The provocative concentration of the agonist that increased Penh to 300% of BL (PC Penh 300) in R cases was 52.98 ± 48.04 mg/mL AMP. Age had no influence on the responder status or PC Penh 300. It was concluded that AMP challenge may offer a new method for the identification of cats with lower inflammatory airway disease, and possibly for monitoring disease progression or response to therapy.     

Method of Supplementation May Affect Cattle Grazing Patterns

Supplement placement can be used to manipulate livestock grazing patterns. The objective of this case study was to compare the effect of low-moisture blocks (LMB) and range cake (barley-based cylindrical cubes, 2 cm in diameter, and 2 to 8 cm long) supplementation on cattle grazing patterns in Montana foothill rangeland. One group of nonlactating cows (n = 79) was fed cake 3 times per week (1.8 kg · cow⁻¹ · feeding⁻¹), and the other group (n = 81) had continuous access to LMB in separate pastures using a crossover design. Movement patterns of cows were recorded with global positioning system collars during four periods (2 wk · period⁻¹) during autumn. Range cake was fed on accessible areas, and LMB were placed in higher and steeper terrain. Intake of LMB averaged (mean ± SE) 318 ± 50 g · d⁻¹. Cows fed LMB (8.07° ± 0.20°) were observed on steeper slopes (P = 0.08) than cows fed range cake (6.96° ± 0.19°). Forage utilization decreased as slope increased to a greater degree when range cake was fed than when LMB was fed (P = 0.001). Cows spent more time (P = 0.05) within 100 m of LMB (274 ± 23 min · d⁻¹) than at range cake feeding sites (67 ± 24 min · d⁻¹). Strategic placement of LMB on high, steep terrain appears to be a more practical and effective approach than traditional hand-feeding range cake on intermediate terrain to improve uniformity of cattle grazing on rugged rangeland.     

Estimation of genetic parameters of racing performance in Iranian Thoroughbred horses

The aim of this study was to estimate the genetic parameters of racing performance and investigate the fixed effects that influence the performance of Thoroughbred race horses. The data included the performance of two, three and four year old horses raced in flat races and consisted of 10,800 time records and 10,912 ranking value. Two criteria were used in order to analyze the performance: racing time and a normalized ranking value. The effects of age of horse at racing and post position were significant for all traits (P < 0.05). The effect of hippodrome also was significant for racing time (P < 0.001). The genetic parameters were estimated by the restricted maximum likelihood (REML) method using DFREML program. The heritability estimates for racing time at 1000, 1400 and + 1600 m were 0.13 (± 0.009), 0.11 (± 0.007) and 0.09 (± 0.009) and for ranking value were 0.15 (± 0.010), 0.17 (± 0.008), 0.13 (± 0.009) and 0.11 (± 0.013) for entire data set, 1000, 1400 and + 1600 m respectively. Estimates of repeatability of racing time for 1000, 1400 and + 1600 m were 0.26, 0.19 and 0.17; and for ranking value were 0.28, 0.32, 0.25 and 0.20 for entire data set, 1000, 1400 and + 1600 m respectively. The genetic correlation of two criteria was 0.68–0.79 depended on distances of races.