Evaluation on the pathogenicity of Erysipelothrix tonsillarum for pigs by immunosuppression with cyclophosphamide or dexamethasone

The pathogenicity of Erysipelothrix tonsillarum was evaluated in pigs immunosuppressed with cyclophosphamide (CY) or dexamethasone (DM). Animals were treated with 15 mg/kg CY (n = 8, five injections), 1 mg/kg DM (n = 8, nine injections) or left untreated (n = 8). On the fifth day after the beginning of drug treatments, swine were inoculated with one of two E. tonsillarum serovar 7 strains (approximately 10⁶ CFU per pig). In the CY-treated group, both circulating neutrophil and lymphocyte counts decreased, whereas in the DM-treated group, lymphocyte counts decreased but neutrophil counts increased. During the observation period, none of the CY- or DM-treated pigs developed clinical signs or gross lesions, as well as non-treated pigs. Growth agglutination antibody titres in all pigs remained unchanged. Our findings indicate that E. tonsillarum strains are avirulent for swine, regardless of immune status.     

Anthelmintic activity of Cocos nucifera L. on intestinal nematodes of mice

In this study, we evaluated the anthelmintic activity of the liquid extracted from the bark of the green coconut (LBGC), as well as butanol extract obtained from LBGC, on mouse intestinal nematodes. Thirty-six naturally infected mice were distributed into six groups receiving the following treatments: Group I: 1000 mg/kg of LBGC; Group II: 2000 mg/kg of LBGC; Group III: 500 mg/kg of butanol extract; Group IV: 1000 mg/kg of butanol extract; Group V: 0.56 mg/kg febendazole; and Group VI: 3% dimethylsulfoxide. The chemical composition of the LBGC and its butanol extract was determined by phytochemical tests. A dose of 1000 mg/kg of butanol extract had 90.70% efficacy in reducing the mouse worm burden (p < 0.05). Phytochemical tests revealed the presence of triterpens, saponnins and condensed tannins in the LBGC and butanol extracts. These results suggest that Cocos nucifera extracts may be useful in the control of intestinal nematodes.     

Tactical treatment with copper oxide wire particles and symptomatic levamisole treatment using the FAMACHA(©) system in indigenous goats in South Africa

Haemonchosis is considered to be the most economically important gastrointestinal disease of small ruminants in the tropics and subtropics. However, chemical anthelmintics, which were the mainstay of control, have been compromised by a high prevalence of resistance worldwide. Copper oxide wire particles (COWP) have been shown to have anthelmintic effects, but few studies have examined their use under field conditions. The use of COWP was therefore evaluated as a tactical anthelmintic treatment in indigenous goats raised under communal farming conditions in Bergville, KwaZulu-Natal Province, South Africa. At the beginning of the summer rainfall season (October 2007), the faecal egg counts of 172 female goats belonging to 15 farmers were determined and this sampling continued every four weeks until the second week of January 2008. The goats within each of the 15 herds were ranked according to their faecal egg counts for this week. The goats were sequentially paired off within each ranking starting with those goats with the highest counts. One goat from each pair was randomly allocated to a treated or control group. Two weeks later, a 4 g COWP bolus was randomly administered to each goat in the treated group. Faecal egg counts were carried out on the goats two weeks following treatment, and the sampling of the goats then proceeded every four weeks until October 2008. Except for the six-week period prior to the administration of the COWP, the goats were examined according to the FAMACHA^© system and symptomatically treated with 12 mg/kg levamisole when anaemic. The percentage reduction in faecal egg count due to the COWP treatment was 89.0%. Mean pre- and post-treatment faecal egg counts for the COWP-treated group (n = 73) were 2347 eggs per gram of faeces (epg) and 264 epg, respectively. The corresponding values for the untreated controls (n = 66) were 2652 epg and 2709 epg. The prevalence of Haemonchus spp. larvae in pre- and post-treatment faecal cultures was 72% and 46%, respectively. Symptomatic anthelmintic treatments in combination with mid-summer tactical treatments with COWP appear to be useful strategies for the control of Haemonchus contortus in indigenous goats in this farming system and this approach could have application in other similar agro-ecological zones.     

Efficacy of levamisole alone and in combination with mebendazole against Gongylonema pulchrum infection in rabbits

Gongylonema pulchrum is an important parasite of captive primates. Twelve rabbits were infected with 30 third-stage larvae of G. pulchrum. At 4–7 months post-infection, animals were administered levamisole at a single dose of 12 mg/kg, levamisole at 8 mg/kg three times at 2-day intervals, levamisole at a single dose of 8 mg/kg after administration of mebendazole at 70 mg/kg for 3 days or 8 ml of distilled water for 3 days (control). Necropsy at 14 days after treatment revealed that single and multiple dosages of levamisole reduced nematode burdens by 68.4% and 89.5%, respectively. The combined regimen of mebendazole and levamisole exhibited high efficacy for treating G. pulchrum located widely within the upper digestive tract, with a reduction of 98.2%. These results suggest that this combined chemotherapy treatment may be effective against G. pulchrum infection, including buccal and lingual gongylonemiasis in primates.     

The efficacy of eprinomectin extended-release injection against Hypoderma spp. (Diptera: Oestridae) in cattle

The efficacy of eprinomectin in an extended-release injection (ERI) formulation was determined in cattle harboring naturally acquired infestations of first- or second- and third-stage larvae of Hypoderma spp. in three studies conducted according to the same protocol in the USA (two studies) and Germany (one study). Thirty cattle sourced from herds with a history of Hypoderma infestation were included in each study. Cattle were formed into replicates of three animals each on the basis of pre-treatment anti-Hypoderma antibody titers. Within replicates each animal was randomly allocated to one of the following treatments: ERI vehicle (control) at 1 mL/50 kg bodyweight, administered once on Day 0; Eprinomectin 5% ERI at 1 mL/50 kg bodyweight (1.0 mg eprinomectin/kg), administered once on Day 0 (when larvae were expected to be first instars); or Eprinomectin 5% ERI at 1 mL/50 kg bodyweight (1.0 mg eprinomectin/kg), administered once when larvae were second or third instars (study dependent, Day 73, 119, or 140). Treatments were administered by subcutaneous injection in front of the shoulder. In all studies, emerging and/or expressed Hypoderma larvae were recovered, speciated, and counted and viability was determined. Eprinomectin LAI treatment was 100% (p < 0.05) efficacious against first- and second- or third-stage larvae of Hypoderma bovis (two studies) and Hypoderma lineatum (one study). All animals accepted the treatment well. No adverse reaction to treatments was observed in any animal in any study.     

Correlating the immune response with the clinical-pathological course of persistent mastitis experimentally induced by Mycoplasma agalactiae in dairy goats

To correlate the clinical course of mycoplasma mastitis with its immune response, right mammary glands of 15 lactating goats were inoculating with 10¹⁰ colony-forming units (cfu) of Mycoplasma agalactiae (Ma). Before sacrificing the animals at 5, 15 or 45 days post-inoculation (dpi), blood Ma antibody titres and milk mycoplasma colony and somatic cell counts were monitored. Ma colonised the mammary gland and milk counts increased to over 10¹² cfu/ml within 5 dpi. During this period, an innate immune response involving neutrophils and macrophages was observed, and Ma antigen appeared in the degenerated acinar epithelium. From 7 dpi, a specific antibody response coincided with reduced viable mycoplasmas in milk. The humoral immune response was limited; by 37 dpi, all animals scored negative for anti-Ma antibodies, and around 10⁸ cfu/ml were shed. Results indicate an early immune response to Ma inoculation unable to control mycoplasmal invasion. An ensuing humoral response, despite reducing the mycoplasma burden, leads to chronic, persistent infection.     

Investigation of Immunmodulatory effects of levamisole and vitamin E on Immunity and some blood parameters in newborn Jersey calves

The immunmodulatory effects of dl-α tocopherol (vitamin E) and levamisole on the immune system and some blood parameters of newborn Jersey calves were investigated with the present study. Treatment groups 1, 2 and 3 were injected 13,3 ml isotonic saline solution (0,9% NaCl), 3 mg/kg levamisole HCl and 2000 IU vitamin E weekly, starting at birth until the age of two weeks. Average serum IgM levels of the control, levamisole and vitamin E calves were 111,7 ± 9,3 mg/100 ml, 251,9 ± 27,6 mg/100 ml, 202,2 ± 43,3 mg/100 ml respectively on day 22. Average serum IgG levels of the levamisole and vitamin E groups elevated, compared to the control group on days 1, 8, 15 and 22. However, there were stastistically differences in treatment and control groups for serum total cholesterol, low density lipoprotein (LDL), high density lipoprotein (HDL), triglyceride and cortisol values and whole blood counts. All differences were in the reference ranges. Levamisole and vitamin E could be used as an alternative way for their beneficial effects such as improving the humoral immune responses of calves and their safety and practical use against the neonatal period infections in the field.     

Effects of anesthetic protocols on electroejaculation variables of Iberian ibex (Capra pyrenaica)

The effects of three intramuscular anesthesia protocols - detomidine 190 μg/kg plus ketamine 2 mg/kg, detomidine 270 μg/kg plus ketamine 1.4 mg/kg, and tiletamine 3.4 mg/kg plus zolazepam 3.4 mg/kg - on penis protrusion and ejaculation variables were compared in nine captive Spanish ibex (Capra pyrenaica) subjected to electroejaculation. Body temperature, heart, and respiratory rates, as well as a number of plasma biochemical variables were also recorded prior to and during anesthesia. The detomidine plus ketamine protocols induced bradycardia and increased respiratory rate. However, the tiletamine/zolazepam protocol did not affect heart and respiratory rates. None of the three protocols caused a substantial change in rectal temperature, yet all protocols caused a significant increase in plasma glucose levels. Differences in anesthetic protocols did not affect sperm quality or quantity. However, choice of anesthetic protocol affected (P < 0.05) the degree of penis protrusion and the electrical pulse sequence required to achieve ejaculation. Results of this study support a recommendation of detomidine 270 μg/kg plus ketamine 1.4 mg/kg for anesthesia of Spanish ibex undergoing electroejaculation.     

Study of ehrlichiosis in kennel dogs under treatment and prevention during seven months in Dakar (Senegal)

In Dakar kennels where morbidity and mortality attributed to diseases transmitted by ticks were high, we conducted a field study to assess the prevalence of Ehrlichia canis, Anaplasma platys and Babesia spp. infections in two kennels (n = 34 dogs) and to study the impact of tick protection. The first day of the study, the E. canis PCR were positive in 18 dogs (53%). A. platys was found in one dog and all dogs were negative for Babesia spp. After one month of doxycycline treatment, the number of PCR positive dogs decreased significantly to 2 (5.9%). During seven months, all dogs were treated monthly topically with a novel combination (Certifect^®, Merial) delivering at least 6.7 mg fipronil/kg body weight, 8.0 mg amitraz/kg and 6 mg (S)-methoprene/kg. The number of PCR positive dogs remained stable all over the seven months, with 4 dogs being positive at Day 90 and 2 at Day 210. The combination of treatment and monthly prevention had a significant effect in the two kennels. All dogs remained healthy, which was not the case in previous years.     

Effect of weaning age and postweaning feeding programme on the growth performance of pigs to 10 weeks of age

This study aimed to determine the effects of weaning age and postweaning feeding programme on pig performance and health. In experiment 1, 96 same gender pairs of pigs weaned at 3, 4 and 5 weeks of age were used in a 3 (weaning age)×4 (dietary programme) factorial design experiment. Pigs received different amounts of a phase 1 diet (16.2 MJ/kg digestible energy (DE) and 16.2 g/kg lysine) and phase 2 diet (15.3 MJ/kg DE and 15.0 g/kg lysine): (A) very low (VL, 1 kg phase 1 and 3 kg phase 2 diet per pig); (B) low (L, 2 kg phase 1 and 6 kg phase 2 diet per pig); (C) medium (M, 3 kg phase 1 and 9 kg phase 2 diet per pig) or (D) high (H, 4 kg phase 1 and 12 kg phase 2 diet per pig), followed by a cereal based phase 3 diet (15.0 MJ/kg DE and 13.8 g/kg lysine) to 10 weeks of age. In experiment 2, faecal samples from 60 pigs weaned at 3, 4 and 5 weeks of age were collected at 10 days postweaning and analysed for Escherichia coli and lactic acid bacteria counts. In experiment 1, there were no interaction effects of age×dietary programme on growth performance. Dietary programme did not affect growth performance from weaning to 10 weeks of age. From weaning to 10 weeks of age, increasing weaning age increased average daily gain (ADG; 363, 402, and 476 g for 3, 4 and 5 weeks respectively; s.e. 17.6; P<0.001), average daily feed intake (ADFI; 560, 620, and 680 g; s.e. 26.1; P<0.001), and improved feed conversion ratio (FCR; 1.57, 1.55, and 1.43; s.e. 0.045; P<0.05). However, weaning age had no effect (P>0.05) on pig weight at 10 weeks of age. In experiment 2, 3 week weaned pigs had higher faecal counts of E. coli (P<0.05) than 4 week weaned pigs and higher faecal counts of lactic acid bacteria (P>0.01) than 5 week weaned pigs at 10 days postweaning. In conclusion, feeding higher amounts of phases 1 and 2 diets did not affect performance at any of the weaning ages tested. Increasing weaning age increased growth performance between weaning and 10 weeks of age, but had no effect on the resulting body weight. Pigs weaned at 3 weeks of age had increased counts of selected faecal bacteria compared to those weaned later.     

A zoospore inhibition technique to evaluate the activity of antifungal compounds against Batrachochytrium dendrobatidis and unsuccessful treatment of experimentally infected green tree frogs (Litoria caerulea) by fluconazole and benzalkonium chloride

Effective and safe treatments of chytridiomycosis in amphibians, caused by Batrachochytrium dendrobatidis, are needed to help prevent mortality in captive programs for threatened species, to reduce the risk of spread, and to better manage the disease in threatened populations. We describe a simple method to determine minimum inhibitory concentrations (MICs) of antifungal agents that involves adding zoospores to various drug concentrations in 96 well plates and microscopic observation after four days. We report results from testing 10 commercially available antifungal compounds: benzalkonium chloride (<0.78 μg/ml), povidone iodine (312.5 μg/ml), amphotericin B (3.125 μg/ml), fluconazole (<1.56 μg/ml), itraconazole (<1.56 μg/ml), enilconazole (<1.56 μg/ml), mercurochrome (6.25 μg/ml), sodium chloride (12.5 mg/ml), methylene blue (<1.56 μg/ml) and Virkon (3.125 μg/ml). For treatment trials of juvenile Litoria caerulea, baths of benzalkonium chloride at 1 mg/L and fluconazole at 25 mg/L were used on 18 experimentally infected frogs per treatment. Although these treatments resulted in longer survival times (mean 43.7 ± 11.3 days) than in the untreated controls (37.9 ± 9.3 days), the mortality rate was still 100%. Higher doses of fluconazole are suggested for further animal trials.     

Potentiation of triclabendazole action in vivo against a triclabendazole-resistant isolate of Fasciola hepatica following its co-administration with the metabolic inhibitor, ketoconazole

An in vivo study in the laboratory rat model has been carried out to monitor morphological changes in adult Fasciola hepatica over a 4-day period resulting from co-treatment with triclabendazole (TCBZ) and ketoconazole (KTZ), a cytochrome P450 inhibitor. Rats were infected with the triclabendazole-resistant Oberon isolate of F. hepatica, dosed orally with triclabendazole at a dosage of 10 mg/kg live weight and ketoconazole at a dosage of 10 mg/kg live weight. Flukes were recovered at 24, 48, 72 and 96 h post-treatment (p.t.) and changes to fluke ultrastructure were assessed using transmission electron microscopy (TEM). Results showed an increase in the severity of changes to the fluke ultrastructure with time p.t. Swelling of the basal infolds and the associated mucopolysaccharide masses became more severe with time. Golgi complexes, if present, were greatly reduced in size and number by 96 h p.t., and sub-tegumental flooding was seen from the 72 h time-period onwards. Some sloughing of the tegumental covering over the spines was observed at 96 h p.t. The results demonstrated that the Oberon isolate is more sensitive to TCBZ action in the presence of KTZ than to TCBZ alone, reinforcing the idea that altered drug metabolism is involved in the resistance mechanism. Moreover, they support the concept that TCBZ + inhibitor combinations (aimed at altering drug pharmacokinetics and potentiating the action of TCBZ) could be used in the treatment of TCBZ-R populations of F. hepatica.     

Flavonoid mixture ameliorates increase in erythrocyte osmotic fragility and malondialdehyde concentration induced by Trypanosoma brucei brucei-infection in Wistar rats

The experiment was performed with the aim of investigating the effect of a flavonoid mixture, Daflon® 500 mg (DF) on the erythrocyte fragility and lipoperoxidative changes, induced by Trypanosoma brucei brucei infection in Wistar rats. Fifty adult male rats randomly divided into five groups of 10 animals each were used. Rats in the control group were administered (1 mL/kg) distilled water only, while the other groups were infected with T. brucei brucei and treated with Daflon® 500 mg and/or Diminazene aceturate. At the end of 5 weeks, EDTA-blood samples and serum samples were collected from the rats, and were used to determine erythrocyte osmotic fragility (EOF) and serum malondialdehyde (MDA) concentration respectively. The results showed that EOF and MDA concentration significantly (P < 0.05) increased in the infected untreated group when compared to the treatment groups. Treatment with Daflon® 500 mg and Diminazene aceturate significantly (P < 0.05) reduced trypanosome-induced increases in EOF and lipoperoxidative changes, suggesting possible antioxidant properties of Daflon® 500 mg and its therapeutic value in trypanosomosis.     

Effect of zinc supplementation in pregnant mice during experimental Trypanosoma cruzi infection

Zinc is an essential micronutrient and has significant effects on human growth, development, and immune function. Zinc supplementation or deficiency may affect the course of infection. Zinc enhances immune response against a wide range of viral, bacterial, and parasitic pathogens. In the present study, we investigated the effects of zinc sulphate (ZnSO₄) supplementation (20 mg/kg/day) during pregnancy in mice, Swiss Webster strain infected by the Y strain of Trypanosoma cruzi. Oral supplementation of zinc sulphate in pregnant and non-pregnant infected animals did not affect the count of blood parasites as well as tissue parasitism in the heart, liver, and spleen. Zinc supplementation did not alter female body weight, the length of fetuses and neonates, placental size/weight and mortality rate. Among zinc supplied animals, no significant plasmatic zinc concentrations were observed. Concerning to tissue zinc concentrations, only the liver displayed enhanced values as compared to other organs. For placental parasitism, zinc supplied group displayed a significant decrease in amastigote burdens (P < 0.05). However due to the reduced number of parasite burdens in placenta of animals supplied with zinc, these data suggest that zinc was partially effective in up-regulating the host’s immune response against parasite, probably attenuating the infection in fetuses.     

Physiopathological effects of zearalenone in post-weaning female piglets with or without montmorillonite clay adsorbent

Zearalenone (ZEA), commonly present in corn and its derived products for animals, has caused significant economical impact on swine reproduction in China. The present study therefore attempted to reveal the adverse effects of ZEA (1.3 mg/kg diet) exposure from a viewpoint of damages focusing on the liver and kidney of female piglets. The efficacy of dietary montmorillonite clay in preventing ZEA-induced adverse effects was also determined. Treatments were 1) control; 2) control + 2.5 g/kg clay; 3) control + 1 mg/kg ZEA; 4) control + 1 mg/kg ZEA + 1.25 g/kg clay; 5) control + 1 mg/kg ZEA + 2.5 g/kg clay; 6) control + 1 mg/kg ZEA + 5.0 g/kg clay; 7) control + 1 mg/kg ZEA + 10 g/kg clay. Results showed that pigs fed ZEA-contaminated diet reduced (P < 0.05) platelets, haemoglobin, globulin, triglycerides and high density lipoproteins (HDL) in serum, and increased (P < 0.05) all enzymes activities, cholesterol, urea, and creatinine. Degeneration of the liver and kidney tissues was also found in female piglets fed 1.3 mg/kg ZEA-contaminated diet. Dietary addition of clay showed a positive protection effect on ZEA feeding, and the linear or quadratic effect (P < 0.05) on neutralizing detrimental effects of clay in ZEA feeding were observed. It suggested that feeding ZEA at 1.3 mg/kg diet for 24-d may result in a deleterious effect in female piglets, and clay addition at 5 or 10 g/kg diet can effectively protect against the detrimental effects of the ZEA feeding. These results may have implications for human and animals consuming ZEA-contaminated food or feed.     

Inflammation-associated responses in piglets induced with post-weaning colibacillosis are influenced by dietary protein level

Forty piglets (average body weight = 5.32 kg) were used to investigate the effect of dietary crude protein (CP) content on immunological responses following a challenge with enterotoxigenic Escherichia coli (ETEC) K88. Pigs, housed 4 per pen, were randomly allotted to 2 diets: 1) a high, 225 g/kg CP diet (HCP) or 2) a low, 176 g/kg CP diet (LCP) supplemented with crystalline amino acids. Pigs were orally challenged with 6 mL of an ETEC K88 suspension containing 10¹⁰ cfu/mL on d 8 after weaning. Blood samples were collected from 10 pigs (1 pig/pen) on d 7 (at weaning), −24 h, 8 h, 72 h and 7 d after the challenge for determination of plasma urea N (PUN) and serum concentrations of tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β) and haptoglobin (Hp). Tumor necrosis factor alpha, IL-1β and Hp were measured as indicators of inflammatory responses. The concentrations of serum TNF-α at 8 h, 72 h and 7 d after challenge were similar to the level observed at 24 h before challenge but higher (P < 0.05) than the weaning level. Pigs fed the LCP diet had lower (P = 0.032) concentrations of IL-1β (72 vs. 116 pg/mL) at 8 h post-challenge compared with those fed the HCP diet. Likewise, pigs fed the LCP diet tended to have lower (P = 0.088) concentration of Hp (9 vs. 25 mg/dL) compared with those fed the HCP diet at 8 h post-challenge. Compared with the weaning concentration, PUN concentration at 72 h after ETEC challenge was higher (P < 0.05) in pigs fed the HCP diet. The results indicate that the LCP diet supplemented with crystalline amino acids reduced inflammatory responses, as indicated by serum IL-1β, in piglets infected with ETEC K88.     

An eprinomectin extended-release injection formulation providing nematode control in cattle for up to 150 days

A series of 10 dose confirmation studies was conducted to evaluate the persistent activity of an extended-release injectable (ERI) formulation of eprinomectin against single point challenge infections of gastrointestinal and pulmonary nematodes of cattle. The formulation, selected based on the optimal combination of high nematode efficacy, appropriate plasma profile, and satisfactory tissue residue levels, includes 5% poly(d,l-lactide-co-glycolic)acid (PLGA) and is designed to deliver eprinomectin at a dose of 1.0 mg/kg bodyweight. Individual studies, included 16–30 cattle blocked based on pre-treatment bodyweight and randomly allocated to treatment with either ERI vehicle or saline (control), or the selected Eprinomectin ERI formulation. Treatments were administered once at a dose volume of 1 mL/50 kg bodyweight by subcutaneous injection in front of the shoulder. In each study, cattle were challenged with a combination of infective stages of gastrointestinal and/or pulmonary nematodes 100, 120 or 150 days after treatment and were processed for parasite recovery according to standard techniques 25–30 days after challenge. Based on parasite counts, Eprinomectin ERI (1 mg eprinomectin/kg bodyweight) provided >90% efficacy (p < 0.05) against challenge with Cooperia oncophora and Cooperia surnabada at 100 days after treatment; against challenge with Ostertagia ostertagi, Ostertagia lyrata, Ostertagia leptospicularis, Ostertagia circumcincta, Ostertagia trifurcata, Trichostrongylus axei, and Cooperia punctata at 120 days after treatment; and against challenge with Haemonchus contortus, Bunostomum phlebotomum, Oesophagostomum radiatum and Dictyocaulus viviparus at 150 days after treatment. Results of a study to evaluate eprinomectin plasma levels in cattle treated with the Eprinomectin ERI formulation reveal a characteristic second plasma concentration peak and a profile commensurate with the duration of efficacy. These results confirm that the Eprinomectin ERI formulation can provide high levels of parasite control against a range of nematodes of cattle for up to 5 months following a single treatment.     

Anthelmintic activity of artesunate against Fasciola hepatica in naturally infected sheep

In light of rapidly spreading triclabendazole resistance alternative fasciocidal drugs are urgently needed. Following up on promising results obtained with artemether in Fasciola hepatica infected sheep, we here report the efficacy and safety of artesunate in sheep with a natural F. hepatica infection. Artesunate was administered intravenously and intramuscularly, adverse events were monitored and drug efficacy was elucidated by means of faecal egg and worm burden reductions. A single 40 mg/kg intravenous dose of artesunate induced an egg count reduction of 68.9% and a worm burden reduction of 77.4%. Intramuscular artesunate at 40 mg/kg reduced faecal egg count and worm burden by 97.6% and 91.9%, respectively; whereas at 60 mg/kg it caused 93.2% and 87.1% reduction in faecal egg count and worm burden, respectively. Three sheep died 24-72 h post-treatment with a double dose of 40 mg/kg intramuscular artesunate, showing lethargy, sialorrhoea, reduced rumination and tremors. Egg and worm burden reductions of 93.3% and 83.9%, respectively, were calculated in the three surviving sheep. In conclusion, the interesting fasciocidal properties of artesunate in sheep warrant further investigations with an emphasis on toxicity studies.     

Effects of mosapride citrate, metoclopramide hydrochloride, lidocaine hydrochloride, and cisapride citrate on equine gastric emptying, small intestinal and caecal motility

Objective

Although extensive work has been done to elucidate the beneficial and unfavorable effects of gastrointestinal prokinetic agents in humans, little is known on the effects of these agents in horses. In this study, we compared the effects of mosapride, metoclopramide, cisapride, and lidocaine on equine gastric emptying, jejunal and caecal motility and evaluated these agents’ adverse drug reactions (ADRs).

Animals

Seven healthy adult Thoroughbreds.

Procedure

Mosapride 1.0 mg/kg and 2.0 mg/kg, metoclopramide 0.2 mg/kg, and cisapride 1.0 mg/kg were dissolved in 100 mL distilled water for oral administration. Lidocaine 1.3 mg/kg was mixed with 500 mL saline for a 30-min intravenous infusion. Oral administration of 100 mL distilled water was used as control. Gastric emptying was evaluated using ¹³CO₂ breath test, and jejunal and caecal motility was assessed by electrointestinography.

Results

The present study demonstrates that mosapride at doses of 1.0 mg/kg and 2.0 mg/kg facilitates gastric emptying in horses. Improved jejunal motility was observed following administration of mosapride (1.0 mg/kg and 2.0 mg/kg), metoclopramide (0.2 mg/kg), and cisapride (1.0 mg/kg). Similarly, improved caecal motility was observed following administration of mosapride (2.0 mg/kg).

Conclusions and clinical relevance

This study shows that among the prokinetic agents studied here, only mosapride (2.0 mg/kg) promotes jejunal and caecal motility in horses. Considering mosapride ADRs profile, it is believed that this compound is useful in the treatment of diseases associated with decreased GI motility, including postoperative ileus.     

Effect of δ-aminolevulinic acid on growth performance, nutrient digestibility, blood parameters and the immune response of weanling pigs challenged with Escherichia coli lipopolysaccharide

This study investigated the effects of dietary δ-aminolevulinic acid (ALA) on growth performance, nutrient digestibility, blood parameters and whether ALA improved the immune response of weanling pigs challenged with Escherichia coli lipopolysaccharide (LPS). Eighty pigs (body weight = 7.21 ± 0.51 kg) were allotted to four dietary treatments, with four pens per treatment and five pigs per pen. Basal diets were supplemented with 0, 5, 10, and 15 mg/kg ALA (as-fed basis) and fed for 35 days. At the end of the feeding period, 10 pigs were selected from both the 0- and 10-mg/kg ALA treatment groups; five were injected i.p. with LPS (50 μg/kg BW) and the other five pigs with an equivalent amount of sterile saline, resulting a 2 × 2 factorial arrangement. Blood sample and rectal temperature data were collected at 0, 2, 4 and 12 h after challenge. Growth performance was not affected by dietary treatments over the total experimental period. However, dry matter (DM) and nitrogen (N) digestibility was improved in the 15-mg/kg ALA treatment group at day 35 (P < 0.05). Serum hemoglobin (Hb) and iron levels were also increased, with the 10-mg/kg ALA treatment showing the highest concentration (P < 0.05). On day 35, red (RBC) and white blood cell (WBC) counts were elevated, with the 5- and 10-mg/kg ALA treatments having the highest counts (P < 0.05). During challenge, LPS injection elevated rectal temperature at 2 and 4 h postchallenge (P < 0.05). Plasma cortisol concentration was also increased by LPS injection at 2 and 4 h postchallenge and an ALA-alleviating effect was evident at 2 h postchallenge (P < 0.01). Concentration of plasma insulin-like growth factor-I (IGF-I) was increased in the ALA-supplemented treatments at 2 h postchallenge (P < 0.05). LPS injection increased plasma tumor necrosis factor-α (TNF-α) concentrations at 2, 4 and 12 h (P < 0.01), while an ALA-alleviating effect was observed at 2 and 4 h postchallenge (P < 0.05 and P < 0.10, respectively). Challenge with LPS decreased WBC counts at 2 and 4 h postchallenge (P < 0.01). At 12 h postchallenge, RBC, WBC and lymphocyte counts were affected by LPS challenge, while an ALA effect was only observed on WBC count (P < 0.05). In conclusion, dietary supplementation of ALA in weanling pigs can improve DM and N digestibilities, and iron status and have a beneficial effect on the immune response during inflammatory challenge.