Efficacy of phage therapy in pigs

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Global concerns exist that livestock receiving antibiotics as growth promotants and clinically can excrete residues leading to an increased incidence of antimicrobial resistance. The presence of antibiotic resistance genes and the diversity of the fecal microbiome are specie dependent, vary by geographical location and are influenced by management practices (Rothrock et al., 2021). As an alternative to chemical antibiotics, bacteriophages (phages) have gained renewed interest (Kortright et al., 2019). Phages are viruses capable of infecting bacteria, replicating within the host and causing host lysis. Targeting species of bacteria with phage can serve as a bactericide and decrease the likelihood of developing multidrug resistance. A recent meta analysis explored the pros and cons of phage therapy in swine providing new insight into their application as antibiotic alternatives (Desiree et al., 2021).     

我国健康猪源大肠杆菌对四环素类药物耐药性的Meta分析

旨在系统评价我国健康猪源大肠杆菌对四环素类药物耐药性的情况,为养殖业合理用药决策提供依据.计算机搜索PubMed、Web“sci-ence、SinoMed、CNKI等10个数据库.应用Revman 5.3软件进行Meta分析,并对各研究间异质性进行评价.共纳入20篇符合条件的研究,共4 343株分离自健康猪源的大肠杆菌...     

Prevalence of fasciolosis in livestock and humans: A systematic review and meta-analysis in Iran

Fasciolosis is a re-emerging disease of livestock and rarely human, being endemic in Iran. Herein, we aimed to quantitatively assess the human seropositivity and prevalence of animal fasciolosis in our country. English and Persian databases were searched for online literature. In total, 10 human seroprevalence studies and 49 animal investigations were obtained from January 1999 to March 2019. Only animal studies were included in meta-analysis. The highest human seroprevalence was detected in Guilan province (326/452; 50%). The pooled prevalence of the animal infections was calculated as 6.2% (95% CI = 5.8%–6.5%). In detail, the prevalence ranges in three hosts included as 4.2% (95% CI = 3.8%–4.5%) in sheep, 9% (95% CI = 8.0%–9.9%) in cattle and 3.1% (95% CI = 2.4%–3.7%) in goat. The highest prevalence rate was observed in the north, 11.8% (95% CI = 8.4%–15.1%), while the lowest prevalence was detected in the central Iran with 1.8% (95% CI = 1.3%–2.3%). Egger’s regression test revealed no significant publication bias (P = 0.307). Also, there was no remarkable correlation between weighted prevalence and sample size (P = 0.249) as well as year of study (P = 0.172). These findings would be necessary for better preventive strategies in case of human and animal Fasciola infections as well as snail intermediate hosts.     

Prevalence of human visceral leishmaniasis in Iran: A systematic review and meta-analysis

Leishmania infantum is the main cause of human visceral leishmaniasis (HVL; also known as kala-azar) in the Middle East and may be fatal if left untreated. This disease was first reported in 1949 in Iran. Despite marked improvements in hygiene and sanitation conditions, the disease is still endemic in some parts of Iran. It is difficult to determine the current prevalence of HVL in Iran due to the scarcity of comprehensive studies in this regard. In response to this gap, a systematic review and meta-analysis was conducted to gain better understanding of HVL epidemiology in the general population of Iran. English and Persian databases were searched for studies reporting the prevalence and risk factors associated with HVL in the Iranian people from January 1995 to December 2019. The reported data were selected according to inclusion and exclusion criteria. The pooled prevalence of HVL infection and its 95 % confidence intervals were calculated. Quality assessment, heterogeneity testing and publication bias assessment were also done. Literature search revealed 3634 studies, of which 35 studies met our eligibility criteria, with a total of 50,716 individuals. The meta-analysis was performed on 31 out of 35 included studies. The estimated pooled prevalence of HVL infection according to seropositivity was 2% (95 % CI: 1–2%) in the general population of Iran in which western and northern provinces had the lowest and the highest prevalence, 0.5 % (95 %CI, 0.2−0.7%) and 3% (95 %CI, 1–5 %), respectively. The seroprevalence of HVL among females (2%; 95 %CI, 1–2 %) was more than males (1%; 95 %CI, 1–2 %). The ≤10 and >10 years age groups had similar seroprevalence rates (1%, 95 %CI, 1–2 % versus 1%, 95 %CI, 0–1 %, respectively). There was no significant difference in terms of geographic area, age and sex. Of 31 studies included in the meta-analysis, the most common diagnostic test was the direct agglutination test (96.77 %). To the best of our knowledge, this is the first systematic review of the prevalence of HVL in Iran. The results showed a low seroprevalence of HVL infection. However, the lack of published reports of HVL in an area does not exclusively mean the absence of the disease or carrier. We therefore recommend further studies in this regard.     

抗猪流感噬菌体单链抗体库的构建与筛选

利用噬菌体展示技术构建猪流感病毒噬菌体抗体库,并筛选出猪流感高特异性、高亲和力的单链抗体(scFv)。以猪流感病毒免疫BALB/c小鼠,提取脾细胞总RNA,反转录后以cDNA为模板扩增获得VH基因和VL基因,并采用重叠延伸PCR(SOE-PCR),用柔性多肽Linker接头(Gly4Ser)按VH-Linker-VL方式将VH基因和VL基因拼接成scFv基因片段。将scFv基因和pCANTAB5E载体分别双酶切(SfiⅠ/NotⅠ)后连接,转化宿主菌TG1,经过辅助噬菌体M13K07拯救,构建噬菌体单链抗体库。以猪流感病毒为抗原包被96孔酶标板,经过3轮的亲和富集筛选,用Phage-ELISA鉴定阳性重组抗体。本研究成功构建出库容约为4×106cfu/mL抗猪流感病毒的单链抗体库,并筛选出4株特异性抗猪流感病毒的scFv抗体,能够与鼠源阳性多抗进行竞争结合猪流感病毒,为抗猪流感病毒转基因猪的研究奠定基础。     

Efficacy of tramadol for postoperative pain management in dogs: systematic review and meta-analysis

ObjectiveTo evaluate the evidence of analgesic efficacy of tramadol for the management of postoperative pain and the presence of associated adverse events in dogs.Databases usedA comprehensive search using PubMed/MEDLINE, LILACS, Google Scholar and CAB databases with no restrictions on language and following a prespecified protocol was performed from June 2019 to July 2020. Included were randomized controlled trials (RCTs) performed in dogs that had undergone general anesthesia for any type of surgery. Two authors independently classified the studies, extracted data and assessed their risk of bias using Cochrane’s tool. RevMan and GRADE methods were used to rate the certainty of evidence (CoE).ConclusionsOverall 26 RCTs involving 848 dogs were included. Tramadol administration probably results in a lower need for rescue analgesia versus no treatment or placebo [moderate CoE; relative risk (RR): 0.47; 95% confidence interval (CI): 0.26–0.85; I² = 0%], and may result in a lower need for rescue analgesia versus buprenorphine (low CoE; RR: 0.50; 95% CI: 0.20–1.24), codeine (low CoE; RR: 0.75; 95% CI: 0.16–3.41) and nalbuphine (low CoE; RR: 0.05; 95% CI: 0.00–0.72). However, tramadol administration may result in an increased requirement for rescue analgesia versus methadone (low CoE; RR: 3.45; 95% CI: 0.66–18.08; I² = 43%) and COX inhibitors (low CoE; RR: 2.27; 95% CI: 0.68–7.60; I² = 45%). Compared with multimodal therapy, tramadol administration may make minimal to no difference in the requirement for rescue analgesia (low CoE; RR: 1.12; 95% CI: 0.48–2.60; I² = 0%). Adverse events were inconsistently reported and the CoE was very low. The overall CoE of the analgesic efficacy of tramadol for postoperative pain management in dogs was low or very low, and the main reasons for downgrading the evidence were risk of bias and imprecision.     

A systematic review and meta‐analysis of predictors of human hepatitis E virus exposure in non‐endemic countries

The reported incidence of clinical hepatitis E cases is rising in some non‐endemic countries, with concurrent concerns regarding potential hepatitis E virus (HEV) contamination of the blood supply. Therefore, the characterization of major potential sources of human HEV exposure is important to inform risk assessment and public health policy. A systematic review was conducted, including a comprehensive search in six electronic bibliographic databases, verified by hand‐searching reference lists of HEV reviews, and a grey literature search, of the broad research question ‘what is the evidence of the association between predictors of human HEV exposure, and HEV IgG seropositivity, in non‐endemic countries?’ Using forms designed a priori, captured studies were appraised at first‐level screening, second‐level characterization, and third‐level data extraction and risk of bias assessment. Meta‐analysis yielded summary estimates of association between potential predictors and odds of HEV seropositivity. Meta‐analysis and meta‐regression of the odds of HEV seroprevalence in specific groups characterized potential sources of HEV exposure. From 4,163 captured citations, 245 relevant studies underwent data extraction, investigating HEV seroprevalence or predictors in both healthy subjects and targeted patient groups. Across these groups, increasing age was a predictor of HEV IgG seropositivity. Both human immunodeficiency virus patients and haemodialysis patients had significantly increased odds of HEV seropositivity relative to the general population. Working with pigs, in forestry, or in hospitals, was significantly associated with increased odds of HEV seropositivity, as were consumption of meat, pork or game meat, or hunting. Chronological time was not associated with HEV seropositivity within our data sets. Further study of the distribution of potential dietary or behavioural predictors between high and lower prevalence areas within non‐endemic countries could improve our understanding of the relative importance of specific HEV transmission pathways.     

Factors affecting performance response of pigs exposed to different challenge models: a multivariate approach

Factors associated with the severity with which different challenge models (CMs) compromise growth performance in pigs were investigated using hierarchical clustering on principal components (HCPC) analysis. One hundred seventy-eight studies reporting growth performance variables (average daily gain [ADG], average daily feed intake [ADFI], gain:feed [GF], and final body weight [FBW]) of a Control (Ct) vs. a Challenged (Ch) group of pigs using different CMs (enteric [ENT], environmental [ENV], lipopolysaccharide [LPS], respiratory [RES], or sanitary condition [SAN] challenges) were included. Studies were grouped by similarity in performance in three clusters (C1, C2, and C3) by HCPC. The effects of CM, cluster, and sex (males [M], females [F], mixed [Mi]) were investigated. Linear (LRP) and quadratic (QRP) response plateau models were fitted to assess the interrelationships between the change in ADG (∆ADG) and ADFI (∆ADFI) and the duration of challenge. All variables increased from C1 through C3, except for GF, which decreased (P < 0.05). LPS was more detrimental to ADG than ENV, RES, and SAN models (P < 0.05). Furthermore, LPS also lowered GF more than all the other CMs (P < 0.05). The ∆ADG independent of ∆ADFI was significant in LPS and SAN (P < 0.05), showed a trend toward the significance in ENT and RES (P < 0.10), and was not significant in ENV (P > 0.10), while the ∆ADG dependent on ∆ADFI was significant in ENT, ENV, and LPS only (P < 0.05). The critical value of ∆ADFI influencing the ∆ADG was significant in pigs belonging to C1 (P < 0.05) but not C2 or C3 (P > 0.10). The ∆ADG independent of duration post-Ch (irreparable portion of growth) was significant in C1 and C2 pigs, whereas the ∆ADFI independent of duration post-Ch (irreparable portion of feed intake) was significant in C1 pigs only (P < 0.05). Moreover, the time for recovery of ADG and ADFI after Ch was significant in pigs belonging to C1 and C2 (P < 0.05). Control F showed reduced ADG compared with Ct-M, and Ch-F showed reduced ADFI compared with Ch-M (P < 0.05). Moreover, the irreparable portion of ΔADG was 4.8 higher in F (−187.7; P < 0.05) compared with M (−39.1; P < 0.05). There are significant differences in growth performance response to CM based on cluster and sex. Furthermore, bacterial lipopolysaccharide appears to be an appropriate noninfectious model for immune stimulation and growth impairment in pigs.     

Prevalence of hepatitis E virus infection among people and swine in mainland China: A systematic review and meta‐analysis

Hepatitis E virus (HEV) infection remains an important public health problem, and it is endemic primarily in developing countries. This study aimed to evaluate the seroprevalence of HEV among the general population, occupational population and swine in mainland China and its risk factors based on a systematic review and meta‐analysis. Systematic search from EMBASE, PubMed, Web of Science, Cochrane Library and several Chinese databases, such as Wanfang (WF) Data, China National Knowledge Infrastructure (CNKI), Chinese Science and Technology Periodical Database (VIP) and SINOMED, was searched from inception up to 25 April 2018. The overall seroprevalence of HEV and its corresponding 95% confidence interval (CI) as well as the correlation coefficients between different groups were estimated using stata 12.0 and r ‐3.4.1 software. Potential sources of heterogeneity were explored using subgroup and sensitivity analyses. Twenty‐eight studies with 57,274 participants (including human and swine) were included. The seroprevalence of anti‐HEV immunoglobulin G (IgG) among the general population, occupational population and swine was 27.3% (95% CI: 22.4–32.2), 47.4% (95% CI: 40.1–54.8) and 66.4% (95% CI: 61.7–71.1), respectively. The overall prevalence of IgM among the general population was 1.8% (95% CI: 0.7–2.9). The odds ratio for the occupational population, as compared to the general population, was 2.63. The highest anti‐HEV IgG prevalence (59%) was observed in East China, whereas the lowest (34.8%) was noted in Northeast and North China. In the occupational population, the highest prevalence (77.0%) was observed among swine vendors. Seven studies included 30,392 participants (humans and swine); the correlation coefficient for the prevalence of anti‐HEV IgG between the professional population and adult pigs was 0.88. Sensitivity analyses showed that the stability of results was not considered significant. This research found that HEV is common in China, and contact with pork or other pig products may be an important mode of HEV transmission.     

A systematic review and meta-analysis of Hymenolepis nana in human and rodent hosts in Iran: A remaining public health concern

Hymenolepis nana, as a neglected zoonotic helminth, naturally occurs in both humans and rodents. Herein, a systematic review and meta-analysis was carried out to estimate pooled prevalence of H. nana infection among human and rodent hosts for the first time in Iran. PubMed, Web of Science, Scopus, and Embase databases (English articles) and SID and Magiran databases (Persian articles) were systematically searched for relevant studies published from inception till May 24, 2020. Chi² and I² index were used to assess the heterogeneity of the included studies. Publication bias was assessed using Egger's intercept and visual inspection of the funnel plot. Pooled prevalence was estimated using random-effects model with 95 % confidence interval (CI) and depicted as a forest plot. STATA software was used for analysis. The overall pooled prevalence estimate of H. nana in humans included 1.2 % (95 % CI = 1.0–1.4%). Subgroup analysis revealed 2.2 % (95 % CI = 1.8–2.6%) and 0.5 % (95 % CI = 0.3 to 0.8 %) of H. nana infection among school children and food handlers, respectively. In terms of rodent hosts, the overall pooled prevalence of H. nana infection included 13 % (95 % CI = 9.3–16.6%). Subgroup analysis revealed the highest rate of the infection was in Rattus spp. (19.6 %; 95 % CI = 10.6–28.6%), a genus with synanthropic behavior. It seems, despite the advancement in sanitation infrastructure and hygiene status, the H. nana infection compares to other helminthic diseases remains a challenging public health problem in Iran.     

A systematic review of the efficacy of interventions for dynamic intermittent dorsal displacement of the soft palate

There are numerous treatments for correction of dorsal displacement of the soft palate (DDSP). However, the efficacy of these treatments is controversial and there is little consensus on how best to treat this condition. The aims of this study were to systematically review the literature and to assess the evidence on the clinical effects of interventions for dynamic intermittent DDSP. A secondary objective was to assess whether factors relating to study quality affected reported success rates. Twenty-three studies were included, covering a wide number of interventions but also differing widely is terms of study design, sample size, method of diagnosis, outcome measure and the number lost to follow-up. The assessment of adverse effects was severely limited because of lack of reporting. The way in which success is measured appears to have a great effect on the reported results. Research synthesis has been severely limited because of the heterogeneity in the included studies. The low level of evidence makes it difficult to draw firm conclusions as to the efficacy of procedures for DDSP. Hence it is currently not possible to determine which procedure is the most appropriate. This systematic review highlights the difficulties of studying palatal dysfunction and suggests areas where improvements can be made in future studies.     

Conformity and controversies in the diagnosis,staging and follow‐up evaluation of canine nodal lymphoma: a systematic review of the last 15 years of published literature

Diagnostic methods used in the initial and post‐treatment evaluation of canine lymphoma are heterogeneous and can vary within countries and institutions. Accurate reporting of clinical stage and response assessment is crucial in determining the treatment efficacy and predicting prognosis. This study comprises a systematic review of all available canine multicentric lymphoma studies published over 15 years. Data concerning diagnosis, clinical stage evaluation and response assessment procedures were extracted and compared. Sixty‐three studies met the eligibility criteria. Fifty‐five (87.3%) studies were non‐randomized prospective or retrospective studies. The survey results also expose variations in diagnostic criteria and treatment response assessment in canine multicentric lymphoma. Variations in staging procedures performed and recorded led to an unquantifiable heterogeneity among patients in and between studies, making it difficult to compare treatment efficacies. Awareness of this inconsistency of procedure and reporting may help in the design of future clinical trials.     

A systematic review and meta-analysis on the global prevalence and subtypes distribution of Blastocystis sp. infection in cattle: A zoonotic concern

Blastocystosis is an interesting parasitosis, since the parasitic infection is still seriously neglected and a considerable zoonotic evidence is emerging. Blastocystis sp. infects the intestinal lumen of humans and a wide range of animals, while there is a lack of comprehensive information on Blastocystis epidemiology in cattle worldwide. Thus, the present systematic review and meta-analysis were performed by exploring four electronic databases (PubMed, Web of Science, Scopus, and Google scholar) for relevant published papers up to 7th November 2020, utilizing a random-effects model to pool estimations and assign 95 % confidence intervals (CIs). Results of 28 studies (29 datasets) on cattle showed a 24.4 % (95 % CI: 16.9–33.9 %) prevalence for Blastocystis infection. Also, 16 out of 26 reported subtypes (STs) were isolated from cattle, with ST10 (18 datasets) as the highest-reported [32.3 % (95 % CI: 21.6–45.3)] as well as ST24 and ST25 (one study each) as the lowest-reported STs [1.4 % (95 % CI: 0.2–9.1)]. Additionally, among nine well-known zoonotic STs (ST1-ST8 and ST12), all STs except for ST8 were reported from cattle worldwide, demonstrating this animal species as a potential reservoir for human infections. Meanwhile, the overall prevalence of Blastocystis in various subgroups (publication year, WHO regions, countries, continents, and age groups) was analyzed separately. The finding of the present review article highlights the cattle as a significant source of zoonotic transmission of Blastocystis infection to humans, which must be considered for preventive measures.     

Arginine for gestating sows and foetal development: A systematic review

The use of functional amino acids during pregnancy has been linked to improved reproduction in mammals. In this context, arginine is a precursor in the synthesis of numerous molecules, such as nitric oxide and polyamines, which play an important role during reproduction. However, contradictory studies are found in the literature, particularly regarding the amount of supplementation and the period of pregnancy in which it is used. The objective of this study was to evaluate the effects of dietary arginine supplementation for pregnant sows on foetal development via a systematic review. The search for papers was performed during the month of December 2015, in the databases ISI Web of Science, Science Direct, Scopus, and SciELO. From a total of 5675 returned studies, only 13 papers were selected after applying selection criteria. Most (47%) of the studies that evaluated the effects of dietary arginine supplementation on foetal development in pigs used 1% arginine. Supplementation was initiated in the first third of pregnancy in 47% of tests, including in both primiparous and multiparous sows. These studies showed positive results for embryo survival and foetal development, evidenced by the increase in placental weight and the number and weight of piglets born alive. Of all evaluated studies, 53% showed benefits on foetal development. It is concluded that supplementing dietary arginine in gestating sows can benefit embryo survival and foetal development. However, to establish a supplementation plan with this amino acid, aspects related to the period of pregnancy, supplementation levels, and source of arginine must be well defined.     

Variability of piglet birth weights: A systematic review and meta-analysis

The objective of the study was to evaluate the effects of litter size and supplementation of functional amino acids on the piglet birth weight variability through of a systematic review and meta-analysis. PubMed, ISI Web of Science, Science Direct, Scopus and SciELO are the main used databases and were searched in January 2019 by using the following keywords and their combinations: within-litter birth, weight variability, piglets, litter size, sow, amino acids, gestation, uniformity, CV and/or SD. Of the 64 pre-selected articles, only articles presenting the coefficients of variation and/or standard deviations according to the litter size and different levels of amino acid supplementation in the sow diets during gestation were selected. The average birth weights of total and live piglets were 43% lower in litters from sows with high prolificacy than those from sows with low prolificacy. The weight variability was affected by high prolificacy sows, with increases of 4.04% and 4.54% in the coefficients of variation of total and born alive piglets respectively (p = .074; p = .009). The standard deviation increased by 180 g in born alive piglets to high prolificacy sows. The coefficients of variation of total and live piglets born from high prolificacy sows showed an increase of 4.04% and 4.54% respectively (p = .07; p < .05). There was a tendency for reduced weight variability with amino acids supplementation when considering the standard deviation of total born (p = .072). However, reproductive performance was not significantly influenced (p > .05). In conclusion, the average litter weight and the number of piglets born influence weight variability. Amino acids supplementation may reduce the birth weight variability between piglets. However, this effect depends on the amino acid used, the levels of supplementation and on other factors not completely addressed in this study. Thus, more research is necessary to fully elucidate this topic.     

Effectiveness of acupuncture in veterinary medicine: systematic review

Acupuncture is a popular complementary treatment option in human medicine. Increasingly, owners also seek acupuncture for their animals. The aim of the systematic review reported here was to summarize and assess the clinical evidence for or against the effectiveness of acupuncture in veterinary medicine. Systematic searches were conducted on Medline, Embase, Amed, Cinahl, Japana Centra Revuo Medicina and Chikusan Bunken Kensaku. Hand-searches included conference proceedings, bibliographies, and contact with experts and veterinary acupuncture associations. There were no restrictions regarding the language of publication. All controlled clinical trials testing acupuncture in any condition of domestic animals were included. Studies using laboratory animals were excluded. Titles and abstracts of identified articles were read, and hard copies were obtained. Inclusion and exclusion of studies, data extraction, and validation were performed independently by two reviewers. Methodologic quality was evaluated by means of the Jadad score. Fourteen randomized controlled trials and 17 nonrandomized controlled trials met our criteria and were, therefore, included. The methodologic quality of these trials was variable but, on average, was low. For cutaneous pain and diarrhea, encouraging evidence exists that warrants further investigation in rigorous trials. Single studies reported some positive intergroup differences for spinal cord injury, Cushing's syndrome, lung function, hepatitis, and rumen acidosis. These trials require independent replication. On the basis of the findings of this systematic review, there is no compelling evidence to recommend or reject acupuncture for any condition in domestic animals. Some encouraging data do exist that warrant further investigation in independent rigorous trials.