Prevalence and distribution of gastrointestinal helminths and their effects on weight gain in free-range chickens in Central Zambia

Examination of helminths from gastrointestinal tracts of 125 free-range chickens in Zambia revealed a 95.2% prevalence rate. The species and their prevalences were: Allodapa suctoria (85.6%), Tetrameres americana (80.8%), Ascaridia galli (28.8%), Gonglonema ingluvicola (50.4%), Raillietina spp. (81.6%) and Heterakis gallinarum (32.8%). No trematodes or Syngamus trachea were found. Mixed infections accounted for 88.2% as compared to 7.2% of single infections. Effects of helminthoses on weight gain were investigated in 100 growing chickens randomly assigned to treatment (levamisole) and untreated control groups. There was a significant mean (±SEM) weight gain (grams) of 812.8 ± 51.4 in the treatment group and 623 ± 57.4 in the control group (p < 0.01). The mean (±SEM) worm burdens from the control group and the treatment group were 96.3 ± 5.61 and 22.05 ± 2.61, respectively. These results confirm the higher risk of helminth infections in free-range systems and may explain the deleterious effects in chickens.     

苦豆子总碱涂膜剂安全性试验研究

为研究苦豆子总碱涂膜剂在预防和治疗奶牛乳房炎方面的安全性,选用皮肤完好的健康家兔,观察家兔对苦豆子总碱涂膜剂皮肤刺激反应症状,并根据皮肤刺激反应的评分标准进行评分;选用皮肤完好的健康豚鼠进行试验,观察豚鼠对苦豆子总碱皮肤变态反应症状,根据皮肤刺激反应的评分标准进行评分。结果表明:苦豆子总碱涂膜剂皮肤刺激反应积分均值最大值为1.33,属于轻刺激性。根据皮肤变态反应的评分标准,计算所得受试物试验组去除激发受试物后24 h和48 h时的致敏率分别为25%和8.3%,属于轻度致敏强度。试验结果提示,苦豆子总碱涂膜剂临床用药安全,此结论为苦豆子总碱用于奶牛乳房炎的预防与治疗提供了依据。     

氟摄入对胃肠道及其粪钙排出的影响

本研究给 72只小鼠不同浓度的饮水加氟 ,剂量 2 5 /L～ 1 0 0 /L ,以了解氟对消化道的影响以及氟对粪钙排出的影响。在给氟 5 0d时 ,粪钙在不同加氟组间未见明显差别。给氟 90d时 ,胃肠粘膜观察到不同程度的灶性坏死脱落 ,十二指肠粘膜部分绒毛溶解 ,上皮变性坏死。表明一定剂量氟可对上消化道粘膜产生强烈刺激与损伤 ,从而引起厌食等消化道症状     

Prevalence of Giardia duodenalis infection,co-morbidities and associated risk factors in dogs admitted to a veterinary teaching hospital in Israel

Giardia duodenalis causes gastro-intestinal (GI) disease and carries a zoonotic risk. The risk for infection depends on local prevalence and individual immunity, but clinical signs are inconsistent and the role of G. duodenalis in other GI diseases is unknown. The current study aims were to evaluate the prevalence of G. duodenalis in dogs presented to a university veterinary teaching hospital in Israel, investigate risk factors for infection and its associations with other diseases. Fecal samples from 163 dogs were tested for G. duodenalis by an antigen assay (FASTest® Giardia strip). Prevalence of G. duodenalis infection was 11.9 %. It was significantly associated with young age (≤1year) and canine parvoviral enteritis. Housing conditions, signs of GI disease or other systemic diseases were unassociated with infection. In conclusion, G. duodenalis infection prevalence is relatively low in the study population. Young age and diagnosis of co-infections are common, warranting screening for G. duodenalis.     

Gastrointestinal and metabolic effects of feeding schedule on voluntary feed intake and growth of European eel, <Emphasis Type="Italic">Anguilla anguilla</Emphasis>

Gastrointestinal and metabolic influences on short- and medium-term control of voluntary feed intake of European eel were investigated for groups of fish fed at different feeding schedules: 1 meal 2 days⁻¹, 1 meal day⁻¹, 2 meals day⁻¹ and continuous feeding for 12 h and 24 h daily. For fish fed daily, the feeding schedule had no effect on feed intake, metabolism, growth, size variation and body composition. Only fish fed once every 2 days could not completely compensate by increasing their average meal size and showed a reduced feed intake, metabolism and growth. Stomach capacity did not limit meal size and feed intake as large differences in appetite were found for eels with empty stomachs. Feed intake was related to metabolism as the levels of O₂ consumption and NH₄ excretion just before the meal were correlated to average meal size, suggesting that rate (and duration) of metabolism is sensed and is providing information about the metabolic consequences of feed intake and feed processing. Meal size is based on the (expected) scope for metabolism and eels seem to strive to an average daily feed intake, associated with their developmental state (growth potential). Plasticity in this feed intake behaviour, expressed by individual variation in feed intake and day-to-day fluctuations in individual and group intake, is regarded as adaptive on different time scales.     

Lactic acid bacteria in fish: a review

Fish are continuously exposed to a wide range of microorganisms present in the environment, and the microbiota of fish have been the subject of several reviews. This review evaluates lactic acid bacteria in fish, and focuses on the several investigations that have demonstrated that Streptococcus, Leuconostoc, Lactobacillus, and Carnobacterium belong to the normal microbiota of the gastrointestinal tract in healthy fish. However, it is well known that the population level of lactic acid bacteria associated with the digestive tract is affected by nutritional and environmental factors like dietary polyunsaturated fatty acids, chromic oxide, stress and salinity. Pathogenic lactic acid bacteria such as Streptococcus, Enterococcus, Lactobacillus, Carnobacterium and Lactococcus have been detected from ascites, kidney, liver, heart and spleen. Some antibiotic treatments and vaccinations have been proposed to cure or prevent these diseases that seem, however, to spread with the development of fish culture. It has also been reported that some lactic acid bacteria isolated from the gastrointestinal tract of fish can act as probiotics. These candidates are able to colonise the gut, and act antagonistic against Gram-negative fish pathogens. These harmless bacteriocin-producing strains may reduce the need to use antibiotics in future aquaculture.     

Towards a tiered test strategy for plant protection products to address mixture toxicity by alternative approaches in human health assessment

Plant protection products (PPPs) consist of pesticide active substances and co‐formulants. Generally, active substance effects are assumed to dominate in PPP toxicity. Nevertheless, co‐formulants may well affect the toxicity of PPPs via toxicodynamic and toxicokinetic interaction. To account for potential mixture effects and improve PPP data requirements for application in risk assessment, a tiered test strategy is proposed. The strategy is based on a comparison of PPP and active substance toxicity, which enables the prioritisation of PPPs for further testing, adaptation of the toxicological threshold value or removal of toxic co‐formulants from the PPP. Moreover, it focuses on the integrative assessment of existing information and newly generated data using alternative test methods. The proposed strategy will improve PPP toxicological assessment by accounting for mixture toxicity, providing a set of regulatory options for risk assessment and the necessary data for hazard assessment. The predictivity of alternative methods for PPPs will improve by evaluation of their reliability and uncertainty. © 2020 The Authors. Pest Management Science published by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry.     

In vitro effects of Tabernaemontana citrifolia extracts on Haemonchus contortus

Tabernaemontana citrifolia (Apocynaceae) is traditionally used as an anthelmintic preparation for ruminants in Guadeloupe (French West Indies). This study was carried out to evaluate the in vitro effect of this plant against the parasitic nematode of small ruminants Haemonchus contortus. Three extracts (aqueous, methanolic and dichloromethane) of T. citrifolia fruit, leaf and root were tested on four developmental stages of the parasite, using egg hatch assay (EHA), larval development assay (LDA), L3 migration inhibition assay (LMI), and adult worm motility assay (AWM). Compared to the negative control, significant effects were observed for the different parts of T. citrifolia but with differences depending on the parasitic stage; efficacies on the larval development of H. contortus from 88.9% to 99.8% for fruit, from 72.1% to 83.8% for root and from 33.5% to 85% for leaf with dose-dependent effect for the methanolic extract. The root gave the best result on EHA (22.7% efficacy for dichloromethane extract) and AWM (56% efficacy, with dose-dependent effect for dichloromethane extract) and the leaf on LMI (49.4% efficacy). These results suggest that T. citrifolia possess anthelmintic activity against H. contortus. The active ingredients responsible for the activity could be the alkaloid compounds present in the plant parts of the plant.     

A randomized, open-label, positively-controlled field trial of a hydrolyzed protein diet in dogs with chronic small bowel enteropathy

Background: Hydrolyzed protein diets are commonly used to manage canine chronic enteropathies (CE), but their efficacy has not yet been critically evaluated. Hypothesis: A hydrolyzed protein diet is superior to that of a highly digestible (control) diet in the management of CE in dogs. Animals: Twenty‐six dogs (18 test diet, 8 control diet) referred for investigation and management of naturally occurring chronic small intestinal disease. Methods: Randomized, open‐label, positively controlled trial. After a full diagnostic investigation, which included endoscopy, dogs were assigned either to the test diet or control diet on a 2 : 1 basis (test : control). Cases were re‐evaluated 3 times (at approximately 3, 6–12 months, and 3 years). Outcome measures included response of clinical signs (complete, partial, none), change in severity of signs (based upon clinical disease activity index; canine inflammatory bowel disease activity index [CIBDAI]), change in body weight, and need for other therapy. Results: There were no significant differences in baseline characteristics (eg, signalment, body weight, and duration of clinical signs), and histopathologic severity between test and control diet groups. However, despite randomization, CIBDAI was significantly higher in the test diet group (P= .013). Most dogs had responded by first evaluation, with no difference between groups (P= .87). However, significantly more dogs on the test diet remained asymptomatic at both the second (P= .0012) and third (P < .001) re‐evaluation, and the decrease in CIBDAI was significantly greater (P= .010). Conclusions and Clinical Importance: A hydrolyzed protein diet can be highly effective for long‐term management of canine chronic small bowel enteropathy.     

注射用伊维菌素亚微乳的制备及其稳定性研究

以大豆磷脂S75、注射用大豆油和Poloxamer 188为辅料,采用高压匀质法,制备注射用伊维菌素亚微乳。粒度/Zeta电位测定仪测得其粒径、多分散系数和Zeta电位分别为(174.9±8.7)nm、(0.174±0.021)和(-30.9±1.06)mV;加速稳定性试验后,其外观、pH、粒径、电位和药物含量等均符合要求;局部刺激性较普通注射液轻。结果表明,注射用伊维菌素亚微乳制备工艺简单、稳定性好、刺激性小。