Prevalence of Streptococcus suis serotype 2 isolated from pigs: A systematic review and meta-analysis.

Background and Aim: Among Streptococcus suis serotypes, S. suis serotype 2 is the most significant serotype that causes serious diseases in pigs and humans worldwide. The present study aimed to estimate the global prevalence of S. suis serotype 2 isolated from pigs, determine its trend, and explore the factors associated with this serotype. Materials and Methods: We retrieved relevant published studies from PubMed, Scopus, and the Web of Science. The retrieved citations were screened for possible inclusion. Relevant data were then extracted from the included studies. The random-effects model was used for all meta-analyses. A subgroup meta-analysis was used to assess the heterogeneity of the prevalence for four characteristics (continents, sampling organs, reporting unit, and pig's health status). A cumulative meta-analysis was performed to determine the cumulative prevalence over time. Meta-regression analysis was used to determine the trend of pooled prevalence of S. suis serotype 2 over time. Results: Of 600 articles retrieved, 36 studies comprising a total sample size of 6939 isolates or samples from 16 countries of four continents were included for meta-analysis. The pooled prevalence of S. suis serotype 2 isolated from pigs was 13.6% (95% confidence interval [CI], 10.7%-17.1%), with high heterogeneity among the included studies (Cochran's Q, 431.6; p < 0.001; I2 = 91.9%; Table-1). No statistical significance was observed among subgroups of the four characteristics examined. However, the pooled prevalence of S. suis serotype 2 was as high as 16.0% (95% CI, 12.5%-20.3%; n = 16) in diseased pigs compared with 9.9% (95% CI, 5.6%-17.0%; n = 15) in healthy pigs. The pooled prevalence of S. suis serotype 2 isolated from pigs did not significantly decrease over time [regression coefficient = -0.020 (95% CI, 0.046-0.006, p = 0.139)]. The pooled prevalence of S. suis serotype 2 isolated from pigs fluctuated slightly between 13.2% and 17.8% from 2007 to 2023, although the pooled prevalence gradually decreased from 30.6% in 1987 to over 20% in 2003. Conclusion: The global prevalence of S. suis serotype 2 isolated from pigs was estimated to be 13.6% (approximately 10% in healthy pigs and around 16% in diseased pigs). S. suis serotype 2 isolated from pigs did not change significantly over time. These results indicate that S. suis serotype 2 remains a problem for the pig industry and poses a threat to human health.

Feline leptospirosis prevalence worldwide: A systematic review and meta-analysis of diagnostic approaches.

Background and Aim: Leptospirosis in felids (domestic and wild cats) presents an ongoing challenge in our understanding. Numerous studies have reported the detection of Leptospira spp. in these feline populations, highlighting their potential as zoonotic carriers. This systematic review and meta-analysis aimed to provide insight into the global prevalence of leptospirosis in domestic and wild cats. Materials and Methods: We conducted extensive searches across five databases (PubMed, Scopus, Web of Science, Science Direct, and Google Scholar) following the Preferred Reporting Items for Systematic Reviews and Meta-analyses Protocols guidelines. Random-effect meta-analyses were performed using R software version 4.3.0 to estimate pooled prevalence rates. Subgroup meta-analyses were conducted based on continents, diagnostic methods, sample types, and wildcat genera. Results: A total of 71 articles on leptospirosis in domestic cats and 23 articles on leptospirosis in wild cats met the eligibility criteria. Our findings indicated a significantly higher pooled seroprevalence of leptospirosis in domestic cats compared with infection prevalence (9.95% [95% confidence interval (CI), 7.60%-12.54%] vs. 4.62% [95% CI, 2.10%-7.83%], p = 0.01). In contrast, no significant difference was observed in pooled seroprevalence and infection prevalence among wild cats (13.38% [95% CI, 6.25%-21.93%] vs. 2.9% [95% CI, 0.00%-18.91%], p = 0.21). A subgroup meta-analysis of domestic cats revealed significant differences in seroprevalence across continents, sample types, and diagnostic methods. On the contrary, wild cats had no significant differences in any of the subgroups. Conclusion: Leptospira spp. have evidently been exposed to both domestic and wild cats, highlighting their potential roles as reservoir hosts for leptospirosis. These findings highlight the importance of considering felids as a possible public health threat.

Inflammatory cell responses in biliary mucosa during Opisthorchis viverrini infection: Insights into susceptibility differences among hosts.

Background: Individual host susceptibility is believed to be a risk factor in the interaction between the host and the parasite. Since studying time series in humans is limited, animal models are replaced. Aim: This study aims to explore and compare the pattern of inflammatory cell types along the biliary tract and their association with proliferative lesions in the early development of cholangiocarcinoma from susceptible and nonsusceptible animal models. Methods: Thirty male Syrian golden hamsters and 30 BALB/c mice, serving as the susceptible and nonsusceptible animal models, were used in this comparative study. The animals were infected with 50 Opisthorchis viverrini metacercariae via gastric intubation. At days 1, 2, 7, 14, 28, and 56 postinfection (p.i.), five animals were randomly selected from each group and humanely sacrificed. The hepatobiliary tissues were collected and processed for histopathological study. Histochemical and immunohistochemical staining were applied to differentiate the inflammatory cell types. Kruskal-Wallis and Mann-Whitney tests were applied to assess all semi-quantitative and quantitative variables. The correlation between each variable was also analyzed using Spearman rank at a p-value < 0.05. Results: The results demonstrated that mice had different patterns of infiltrating cell types when compared to hamsters. This suggested that the cellular response to the infection in mice occurred earlier than that in hamsters. The response in mice reached its peak at D7 to D14 and then rapidly declined at D28. In contrast, although the inflammatory response in hamsters started slowly, the response reached the peak at D28 and maintained a high level until D56. Significant differences in the number of inflammatory cells between mice and hamsters were seen at D1 (p = 0.047), D7 (p = 0.049), D28 (p = 0.040), and D56 (p < 0.040). Conclusion: The inflammatory responses to O. viverrini infection in the nonsusceptible animal model occurred and declined earlier while the response in the susceptible animal model occurred later in a gradual manner. Both rodents are suitable animal models for the studies of opisthorchiasis susceptibility.

Survivability of freeze- and spray-dried probiotics and their effects on the growth and health performance of broilers.

Background and Aim: Many strains of probiotics have been exploited and used as animal dietary supplements for broiler production. The efficacy and survival of probiotics during production may reflect better activities of the probiotics in the host. This study investigated the effects of freeze- and spray-drying on the survivability and properties of probiotics and their ability to improve the growth and health performance of broilers. Materials and Methods: Probiotic powders of four strains of lactic acid bacteria, Enterococcus faecium CA4, Enterococcus durans CH33, Ligilactobacillus salivarius CH24, Pediococcus acidilactici SH8, and Bacillus subtilis KKU213, were prepared using rice bran/chitosan/carboxy methyl cellulose as the carrier. The survival of each probiotic strain was investigated under stress conditions, including freeze-drying, spray-drying, and simulated gastrointestinal conditions. The body weight gain (BWG) and intestinal histomorphology were determined to assess broiler growth performance. Results: All dried probiotics yielded a high survival rate during freeze-drying (95.8-98.6%) and spray-drying (94.4-98.2%). In addition, an analysis of the main effect revealed that the effectiveness of freeze-drying was higher than that of spray-drying in minimizing the loss of cell viability. The antimicrobial activity of all immobilized dried probiotic strains against Salmonella was maintained. The immobilized probiotics tolerated a low pH value of 2.0 and 0.5% (w/v) bile salt. Probiotic administration of a mixture of the five dried probiotics to 1-day-old hatched male broilers at early and late ages resulted in potential colonization in the broiler intestine, and enhancements in the BWG, lipid metabolism, and gut health (villus height and cryptal depth) were observed in the probiotic-treated groups. Conclusion: The administration of three doses of the spray-dried probiotic mixture at days 15, 17, and 19 after hatching was sufficient to achieve long-term growth and health benefits in broilers. This finding might provide a cost-effective alternative to the administration of commonly used antibiotics in broiler production.

Prevalence of mastitis in dairy animals in Indonesia: A systematic review and meta-analysis.

Background and Aim: Mastitis is an important disease that can reduce milk production and farmer income as well as negatively affect human health. This study aimed to summarize dairy mastitis in Indonesia, both subclinical mastitis (SCM) and clinical mastitis (CM), and its prevalence in different provinces, the diagnostic methods, and the animal species. Materials and Methods: Relevant studies on mastitis in dairy animals in Indonesia were obtained from PubMed, Scopus, ProQuest, Google Scholar, and Garuda. The title and abstract were screened for the eligibility of the studies. The full text of the selected studies was assessed and the data were extracted for analysis. To determine the pooled estimate of the prevalence of mastitis, a random-effects model was performed using the "Meta" and "Metaphor" packages in the R software version 4.2.2. The heterogeneity of several characteristics (mastitis type, provinces, animal species, and diagnostic methods) was evaluated through subgroup meta-analysis. Meta-regression analysis was conducted to assess the trend of mastitis prevalence reports over time. Publication bias was evaluated using Egger's test and a funnel plot. Results: A total of 735 studies were retrieved for the title and abstract screening, which resulted in the final selection of 37 studies with a total of 6050 samples for meta-analysis. The pooled estimate of mastitis prevalence in dairy animals in Indonesia was 59.44% (95% confidence interval [CI], 52.39%-66.49%). Based on mastitis type, SCM had a significantly higher prevalence than CM (58.24% [95% CI, 51.26%-65.23%] vs. 3.31% [95% CI, 1.42%-5.19%]). No significant difference was observed in the analysis of other subgroups. Among provinces, Central Java had the highest prevalence (66.62% [95% CI, 49.37%-83.87%]), whereas Yogyakarta had the lowest (41.77% [95% CI, 14.96%-68.58%]). Based on animal species, cow and goat had a prevalence of 63.42% (95% CI, 55.97%-70.86%) and 44.96% (95% CI, 28.26%-61.66%), respectively. Based on the diagnostic method, the California mastitis test resulted in 60.08% (95% CI, 52.11%-68.06%) and the Institut Pertanian Bogor test, 56.00% (95% CI, 41.20%-70.81%). No significant change in the prevalence of mastitis in Indonesia was observed from 2003 to 2022. Conclusion: This study demonstrates that the pooled estimate of mastitis prevalence in dairy animals in Indonesia is >50%. Based on subgroup analysis, SCM had a higher prevalence than CM; however, the prevalence between provinces, detection methods, and animal species in the 2003-2022 periods was not significantly different. A mastitis control strategy needs to be developed to reduce the prevalence of mastitis and further loss in milk production.

Effects of farrowing induction using cloprostenol on sow farrowing characteristics.

Background and Aim: Previous findings regarding the effects of farrowing induction on the farrowing characteristics of sows are controversial. This study aimed to investigate the effects of farrowing induction on the following characteristics: (1) Proportion of sows that farrowed during working hours, (2) stillbirth rate, (3) number of stillbirths per farrow, (4) dystocia rate per farrow, (5) dystocia rate (the proportion of farrowings that had at least one dystocia event), (6) number of dystocia events per farrow, (6) farrowing duration, (7) birth interval, and (8) birth weight. Materials and Methods: Thirty-eight Landrace x Yorkshire sows were randomly allocated into two groups; the control group and the treatment group. In the control group (n = 18), sows farrowed spontaneously. In the treatment group (n = 20), farrowing was induced approximately 2 days earlier than the herd's average length of gestation (7:00 am on day 114) by injecting cloprostenol into the perivulval region. All sows were supervised throughout their farrowing. We recorded the interval between induction and farrowing; total number of births; number of live, stillborn, and mummified piglet births; number of dystocia events; birth interval; farrowing duration; and birth weight. A generalized linear mixed model, a linear mixed-effects model, the Chi-squared test, and Student's t-test were used to compare outcomes between the two groups. Results: Farrowing induction did not influence the percentage of sows that farrowed during working hours (7 am-5 pm), stillbirth rate, birth weight, and number of dystocia events per farrow. Farrowing induction led to an increase in birth interval, dystocia rate, dystocia per farrow (p < 0.05) and in addition to the percentage of sows that farrowed on the day following induction (60% vs. 27.8%; p < 0.05). Conclusion: Farrowing induction using a single dose of cloprostenol 2 days before the expected farrowing date can be performed with care to concentrate farrowing into a short interval. This can enhance the optimization of cross-fostering and the practice of an all-in-all-out strategy in the swine breeding industry.

Bacillus subtilis QST 713 Supplementation during Late Gestation in Gilts Reduces Stillbirth and Increases Piglet Birth Weight.

Recent studies have shown that probiotic supplementation during late gestation exerts some beneficial effects on reproductive performance of the sows. This study aimed to investigate effects of Bacillus subtilis QST 713 supplementation in gilts on different reproductive criteria. A total of 94 Camborough-48 gilts at day 85 of gestation were randomly allocated into 2 groups: (1) control diet; (2) control diet + 4 × 108 CFU Bacillus subtilis QST 713 per day. Gilts were supplemented until farrowing. At farrowing, litter size, number of piglets born alive, stillbirths, mummies, birth weight, farrowing duration, and birth interval were recorded. Within litter variation of piglet birth weight, depicted as SDBW and CVBW, was also calculated. Results showed that Bacillus subtilis QST 713 supplementation decreased stillbirth rate (1.26 vs. 4.37%, p=0.035) and increased birth weight of the piglets (1303.94 vs. 1234.09 g, p=0.007). Also, the litter size (11.85 vs. 10.67, p=0.03), number of piglets born alive (11.71 vs. 10.23, p=0.008), and litter weight (15473.06 vs. 13174.86 g, p=0.002) in the treatment group were higher than those in the control. Farrowing duration (174.39 vs. 160.81 minutes, p=0.162), birth interval (16.32 vs. 16.59 minutes, p=0.674), SDBW (85.07 vs. 94.65 g, p=0.343), and CVBW (6.42 vs. 7.85, p=0.12) were independent of the Bacillus subtilis QST 713 supplementation. Results of the present study indicate that supplementation of Bacillus subtilis QST 713 during late gestation in gilts reduces stillbirth and increases birth weight thereby improving their reproductive performance.

Protective efficacy of new-generation anticoccidial vaccine candidates against Eimeria infection in chickens: A meta-analysis of challenge trials.

Limitations of live oocyst anticoccidial vaccines in poultry have led to a search for the new generation of anticoccidial vaccines. Several sources may influence the protective efficacy of the new generation of anticoccidial vaccine candidates. Therefore, the objective of this study was to explore the sources influencing the protective efficacy (in terms of the lesion score and the oocyst output) of the new-generation anticoccidial vaccine candidates from the challenge trials in chickens, using meta-analysis techniques. The overall effect size was also estimated to get the overview of the protective efficacy. The study outcomes were the standardized mean difference (SMD) of the lesion score and the difference in mean (DM) of the oocyst output. Descriptive statistics of the oocyst decrease ratio (%) and anticoccidial index (ACI) were also presented. Relevant citations were retrieved from PubMed, Scopus, and Web of Science. Of 1524 retrieved citations, 63 were included for meta-analysis (60 for the lesion score and 44 for the oocyst output). Overall, the new generation of anticoccidial vaccine candidates partially protected chickens from coccidiosis because they significantly reduced the lesion score (SMD = -3.69, [95% CI: -4.08 to -3.29], P < 0.001) with high heterogeneity (I2 = 96.85%) and the oocyst output (DM = -1.48, [95% CI: -1.75 to -1.21], P < 0.001) with high heterogeneity (I2 = 99.69%). The median oocyst decrease ratio was 66.15% (a range from 4.27% to 95.93%, n = 125 subgroups). The median ACI was 164.71 (a range from 50.05 to 196.40, n = 115 subgroups). Vaccine platform and route of administration were identified as sources of heterogeneity for the lesion score and the oocyst output. However, severe publication bias threatened validity of the lesion score outcome. After accounting for other sources of variation, the anticoccidial vaccine candidates were shown to be less effective in reducing the oocyst output when the challenge dose, the length between the day of last immunization and the day of the challenge, or the length between the day of the challenge and the day of sampling, increased. In conclusion, although the new generation of anticoccidial vaccine candidates clearly showed a partial protection of chickens from coccidiosis in experimental trials, the protective efficacy was influenced by several sources, such as the vaccine platform and route of administration. Sources of high heterogeneity such as protein antigens are worth exploring when additionally relevant data are available. Therefore, additional experimental trials in chickens are required to better understand the protective efficacy of the new-generation anticoccidial vaccine candidates.

Incidence of dystocia at piglet level in cloprostenol-induced farrowings and associated risk factors.

Few studies have investigated risk factors for dystocia in swine, although this birthing abnormality can compromise welfare of both sows and piglets by increasing stillbirth rate and decreasing sow productivity. This study aimed to determine risk factors associated with dystocia at piglet level in cloprostenol-induced farrowings. A dystocia event was recorded when a birth interval exceeded 45  min or when manual extraction was applied. Data were collected from 898 piglets born from 77 Landrace × Yorkshire crossbred sows, which were induced for farrowing on day 114 of gestation. Generalized linear mixed models (GLMMs) were used to evaluate the association between dystocia and parity, gestation length, litter size, relative birth order (RBO (%)  =  100  ⋅  birth order/litter size), birth weight, crown rump length, body mass index, ponderal index, piglet's sex, use of oxytocin, and stillbirth. Sows nested in farrowing batches were fitted as random factors in GLMMs. Incidence of dystocia at piglet and farrowing levels was 11.0 % and 75.3 %, respectively. The final multivariate model explained 20.1 % variation of dystocia. RBO had a quadratic effect on dystocia in which incidence of dystocia decreased from RBO  ≤  40 % to RBO  =  60 %-70 %, and then increased to the end of parturition. Piglets with birth weight  >  1700  g and stillborn piglets had higher odds of dystocia in comparison with piglets with a birth weight of 900-1700  g (OR  =  2.63; 95 % CI  =  1.66-4.18) and live-born piglets (OR  =  2.62; 95 % CI  =  1.12-6.15), respectively. This study indicates that dystocia is very common in cloprostenol-induced farrowings and suggests that the last one-third of parturitions is the most important stage to be supervised, and selection for homogenous litters and moderate high birth weight may reduce the rate of dystocia.

Global prevalence of subclinical ketosis in dairy cows: A systematic review and meta-analysis.

The objectives of this study were to estimate the global prevalence of SCK in dairy cows, to identify optimum thresholds for BHB determining, to explore heterogeneity for some particular characteristics (continents, diagnosis techniques, cut-off, sample type, parity, breed, and housing), and to determine the SCK prevalence trend. SCK prevalence levels in dairy cows from various countries were calculated using bibliographic databases up until May 17, 2021 to screen titles and abstracts for possible eligibility. Thirty-eight studies from six continents were then included using a random-effects model to calculate the pooled SCK prevalence. Subgroup meta-analyses were performed to assess the heterogeneity of the prevalence for the above characteristics. Meta-regression and cumulative meta-analysis were used to assess the SCK prevalence trends. The results showed that the global prevalence of SCK in dairy cows was 22.7% [95% CI 21.2-24.3%]. No significant differences in SCK prevalence were observed among continents, diagnostic techniques, cut-off values-≥1.0, ≥1.2 and ≥1.4 mmol/L, sample types-milk and blood, and parities. However, the prevalence in Holsteins (19.8%) was significantly lower than other mixed breeds (23.7%). The SCK prevalence was significantly higher in indoor barns (27.8%) than in pasture and unspecified housing. In meta-regression, the SCK prevalence was not associated with study years or days in milk. The cumulative evidence suggested that the prevalence of SCK in dairy cows was associated with a wide range of risk factors. This study illustrates that the global prevalence of SCK in dairy cows is quite high; therefore, there is an urgent need to globally reduce the SCK prevalence in dairy farms.

Non-infectious risk factors for intrapartum stillbirth in a swine farm in the North of Vietnam.

BACKGROUND AND AIMS: Stillbirth causes considerable loss to the pig farming industry. Methods aimed at reducing stillbirth should base on the understanding of risk factors for intrapartum stillbirth because it accounts for 75% of all stillbirths. Unfortunately, few studies have differentiated between intrapartum and prepartum stillbirths leading to inadequate information about risk factors for sole intrapartum stillbirth. This study investigated risk factors for piglet's intrapartum stillbirth. MATERIALS AND METHODS: Data of 1527 piglets born from 103 sows in one herd were recorded. Generalized linear mixed models were used to determine the relationship between investigated risk factors and intrapartum stillbirth at the piglet level. The potential risk factors were parity, gestation length (GL), litter size (LS), birth order (BO), birth interval (BI), cumulative farrowing duration (CFD), gender, crown-rump length, birth weight (BW), body mass index, ponderal index (PI), and BW deviation. RESULTS: About 60% (60.2%, 62/103) litters had stillborn piglet(s), and the intrapartum stillbirth rate was 5.8% (89/1527). BW deviation (≤0.1 and >0.6 kg), LS >13, GL (<114 and >117 days), PI ≤54, and BO >10 were the most significant factors associated with increased intrapartum stillbirth. No effect of parity, sex, BI, and CFD on intrapartum stillbirth was detected. CONCLUSION: These data stressed the importance of piglets' size and shape in the prediction of intrapartum stillbirth. Furthermore, large LS, high BO, short, and long GL were associated with increased intrapartum stillbirth. The results of this study suggest that procedures aimed at increasing litter homogeneity, optimizing piglets' size and shape, avoiding short and long gestation, and increasing supervision rate, especially at the second half, of the farrowing may reduce piglet's intrapartum stillbirth.

Risk factors associated with dystocia in swine.

BACKGROUND AND AIM: Dystocia in swine can increase the stillbirth rate; however, its importance in pig-breeding systems has been underestimated. Until now, few studies have investigated dystocia and associated risk factors. Therefore, in this study, we aimed to evaluate the effects of various risk factors on dystocia in swine. MATERIALS AND METHODS: Out of 5,557 piglets, we included 4,997 piglets in risk analysis study. The dependent variable was dystocia, which was recorded when a birth interval exceeded 45 min or when obstetric assistance was applied. The independent variables were parity, gestation length, litter size, birth order, gender, presence of a dead piglet, birthweight, crown rump length, body mass index, ponderal index, and oxytocin use. We used generalized linear mixed models to examine the associations between potential risk factors and dystocia at the piglet level. RESULTS: A total of 6% of the piglets were born with a dystocia event, and 47.2% of the farrowing experienced at least one event. Dead piglets and piglets with a crown rump length of >31 cm were associated with an increased dystocia rate. This rate decreased from birth order 2 to 7, stabilized to 11, and then increased till the end of the fetal expulsion process. CONCLUSION: Dystocia is common in swine. Therefore, this condition should be carefully addressed by veterinarians and farrowing house personnel so that its adverse effect on welfare and productivity of sows and survivability of piglets can be reduced. Further studies investigating dystocia status and risk factors in different swine farrowing systems should be undertaken to provide more knowledge about this neglected condition.

Global prevalence of chlamydial infections in birds: A systematic review and meta-analysis.

Chamydia species are bacterial pathogens that can infect a wide range of animal hosts including humans. In birds, Chlamydia psittaci is a leading cause of chlamydial infections (avian chlamydiosis) and is a zoonotic pathogen causing human psittacosis. The objectives of this study were to estimate the global prevalence of chlamydial infections in birds, to assess heterogeneity of the prevalence for some particular characteristics (continents, bird orders, specimen types, and diagnostic techniques), and to determine the trend of the prevalence over time. The relevant citations on the prevalence of chlamydial infections in birds were retrieved from PubMed, Scopus, and Web of Science. Titles and abstracts of the retrieved citations were screened for possible eligibility. Then, full-texts of eligible articles were assessed for data extraction. A random effects model was used for estimating the global prevalence of chlamydial infections in birds and for all other meta-analyses. Subgroup meta-analysis was used to assess heterogeneity of the prevalence for the characteristics mentioned above. Meta-regression analysis and cumulative meta-analysis were used to determine the trend of the prevalence over time. The quality of each included study was also evaluated. Of 579 citations, 74 studies (a total of 39,225 bird samples from 26 countries, five continents) were included in meta-analysis. Almost all included studies reported birds with C. psittaci infections. The global prevalence of chlamydial infections in birds was 19.5 % (95 % CI, 16.3 %-23.1 %). No significant differences of the prevalence were observed among continents, the prevalence ranged from 16.5 % (95 % CI, 9.8 %-26.5 %) in South America to 21.7 % (95 % CI, 12.1 %-35.9 %) in North America. No significant differences of the prevalence were observed among bird orders, the prevalence ranged from 13.4 % (95 % CI, 7.0 %-23.9 %) in Passeriformes to 32.0 % (95 % CI, 20.6 %-46.1 %) in Galliformes. No significant differences of the prevalence were observed between specimen types; the prevalence was 18.4 % (95 % CI, 15.2 %-22.2 %) for live specimens and 26.3 % (95 % CI, 17.1 %-38.1 %) for carcass specimens. The prevalence was significantly higher in non-PCR techniques (29.5 %, [95 % CI, 22.4 %-37.8 %]) than in PCR techniques (15.3 %, [95 % CI, 12.1 %-19.1 %]). The cumulative evidence showed that the prevalence of chlamydial infections in birds has been relatively stable around 20 % since 2012. This study indicates that the global prevalence of chlamydial infections in birds is quite high and all bird orders are potential sources for human psittacosis.

Global Prevalence of Vancomycin-Resistant Enterococci in Food of Animal Origin: A Meta-Analysis.

Vancomycin-resistant enterococci (VRE) are a leading cause of nosocomial infections in patients worldwide. VRE contamination in food of animal origin may create a risk for human health. This study was conducted to estimate the pooled prevalence of VRE in food of animal origin worldwide, to assess the result heterogeneity, and to determine cumulative evidence and the trend of the prevalence over time. Relevant studies were retrieved from PubMed, Scopus, and Web of Science. A random-effects model was used to calculate the pooled prevalence of VRE in food of animal origin. Subgroup meta-analysis was used to assess the heterogeneity of the results. A cumulative meta-analysis and meta-regression were conducted to determine cumulative evidence and the trend of the prevalence of VRE in food of animal origin over time, respectively. Of the 1352 retrieved studies, 50 articles were included. The pooled prevalence of VRE in food of animal origin was 11.7% (95% confidence interval [95% CI] = 8.4 to 16.0). Subgroup meta-analyses showed a significant difference in the prevalence of VRE for two characteristics. First, for the source of food, the prevalence of VRE was highest in aquatic food (43.4% [95% CI = 28.4 to 59.7]) and lowest in dairy food (4.1% [95% CI = 1.7 to 9.8]). Second, for continents, the prevalence of VRE was highest in Africa (18.5% [95% CI = 12.8 to 26.1]) and lowest in North America (0.3% [95% CI = 0.1 to 1.1]). Cumulative evidence showed two distinct features in two different periods. The pooled prevalence of VRE rapidly decreased from 79.3% in 1998 to 13.1% in 2003; it has slightly fluctuated between 10.5% and 20.5% since 2004. The results of the meta-regression indicated that the prevalence gradually decreased over time. In conclusion, the estimate of overall VRE prevalence worldwide in food of animal origin was ∼12%, indicating the burden of VRE contamination in food of animal origin.

Global Prevalence of Chlamydial Infections in Reptiles: A Systematic Review and Meta-Analysis.

Background and Objectives:Chlamydia spp. are potential zoonotic pathogens that can infect a wide range of animal hosts. In reptiles, Chlamydia can cause hepatitis, pneumonitis, and conjunctivitis and it can cause high mortality in young animals. The objectives of this study were to estimate the pooled prevalence of chlamydial infections in reptiles and to assess the trend of these infections over time. Materials and Methods: The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant studies were retrieved from PubMed, Scopus, and Web of Science. The retrieved studies were screened for eligibility. Then, important data were extracted from the included studies. A random effects model was used for all analyses. Subgroup analysis was used to assess heterogeneity for orders of reptiles, continents where the studies were conducted, and types of specimens. Cumulative meta-analysis and meta-regression were used to determine the trend of the prevalence over time. The quality of each included study was evaluated. Results: Of 106 studies (with a total of 2607 samples), 20 met the inclusion criteria and were included in the meta-analysis. The pooled prevalence of chlamydial infections in reptiles was 23.5% (95% confidence interval [CI]: 15.4-34.0). The trend of chlamydial infections increased from 1990 to 2008; thereafter, it was almost stable at slightly over 20%. The most commonly reported Chlamydia spp. were Chlamydia psittaci, Chlamydia pneumoniae, Chlamydia pecorum, and Chlamydia caviae. Among reptiles, the prevalence of chlamydial infections was highest in crocodiles (57.3% [95% CI: 32.5-78.9]). Among continents, the prevalence of chlamydial infections was highest in Australia (68.6% [95% CI: 36.8-89.1]). Conclusions: Based on the included studies, the prevalence of chlamydial infections in reptiles was high, especially in crocodiles. Because C. psittaci and C. pneumoniae are commonly found in reptiles and are well-known zoonotic pathogens, they should be of concern for human health.

Risk factors associated with stillbirth of piglets born from oxytocin-assisted parturitions.

AIM: The present study aimed to investigate the effects of different risk factors on stillbirth of piglets born from oxytocin-assisted parturitions. MATERIALS AND METHODS: Data were collected from a total of 1121 piglets born from 74 Landrace x Yorkshire crossbred sows from a herd. Logistic regression models were used to determine the associations between stillbirth and different risk factors including parity (1, 2, 3-5, and 6-10), gestation length (GL) (112-113, 114-116, and 117-119 days), litter size, birth order (BO), sex, birth interval (BI), cumulative farrowing duration, birth weight (BW), crown rump length, BW deviation, body mass index, ponderal index (PI), and the use of oxytocin during expulsive stage of farrowing. RESULTS: The incidence of stillbirth at litter level and stillbirth rate was 59.5% (44/74) and 8.1% (89/1094), respectively. The final multivariate logistic regression selected BO, BI, PI, GL, and parity as the five most significant risk factors for stillbirth. Increased BO and BI, GL <114 and >116 days, parity 6-10, and low PI increased the stillbirth rate in piglets. CONCLUSION: Several factors previously determined as risks for stillbirth in exogenous oxytocin-free parturitions also existed in exogenous oxytocin-assisted parturitions. One dose of oxytocin at fairly high BO did not increase stillbirth, whereas two doses of oxytocin were potentially associated with increased values.

Bacillus subtilis and lactic acid bacteria improve the growth performance and blood parameters and reduce Salmonella infection in broilers.

AIM: The aim of the study was to determine the potentials and effects of Bacillus subtilis and lactic acid bacteria (LAB) as probiotics on broiler growth, health, and Salmonella infection. MATERIALS AND METHODS: To evaluate the inoculum size applicable for broilers, 1-day-old broilers were orally fed fresh cultures of single strains and a B. subtilis KKU213/Pediococcus pentosaceus NP6 mixture at 108 and 1012 colony-forming unit (CFUs)/mL/chick. The body weight gain (BWG), Salmonella contamination level and total Bacillus and LAB abundances in the crop and intestine were measured. Subsequently, 1-day-old broilers were orally fed of KKU213, CH403, and Pediococcus acidilactici SH8 at 1010 CFUs/mL, followed by inulin. After 35 days, the BWG, Bacillus and LAB abundances in the cecum, blood parameters, and KKU213 colonization were assessed. RESULTS: The broilers fed single strains or KKU213+NP6 exhibited a higher BWG and a higher crop LAB abundance than the controls (p<0.05). Probiotic feeding decreased the intestinal Salmonella abundance and correspondingly increased the LAB abundance. The broilers fed the mixed culture (KKU213+CH403+SH8) followed by prebiotics showed lower mortality, higher blood high-density lipoprotein levels, and lower blood uric acid levels than the controls (p<0.0004). Probiotic feeding significantly increased the Bacillus and LAB counts (p<0.05). A CE330 isolate obtained from the cecum after 35 days of KKU213 feeding was closely related to B. subtilis KKU213. CONCLUSION: B. subtilis KKU213 is a potent probiotic strain that can survive, colonize and reduce Salmonella infection in broilers and improve their growth and health. This strain, combined with different LAB can act synergistically in the gut and promote broiler growth.

Effect of direct-fed microbials on culturable gut microbiotas in broiler chickens: a meta-analysis of controlled trials.

OBJECTIVE: This meta-analysis was conducted to evaluate the overall effect of direct-fed microbial (DFM) or probiotic supplementation on the log concentrations of culturable gut microbiota in broiler chickens. METHODS: Relevant studies were collected from PubMed, SCOPUS, Poultry Science Journal, and Google Scholar. The studies included controlled trials using DFM supplementation in broiler chickens and reporting log concentrations of the culturable gut microbiota. The overall effect of DFM supplementation was determined using standardized mean difference (SMD) with a random-effects model. Subgroups were analyzed to identify pre-specified characteristics possibly associated with the heterogeneity of the results. Risk of bias and publication bias were assessed. RESULTS: Eighteen taxa of the culturable gut microbiota were identified from 42 studies. The overall effect of DFM supplementation on the log concentrations of all 18 taxa did not differ significantly from the controls (SMD = -0.06, 95% confidence interval [-0.16, 0.04], p = 0.228, I2 = 85%, n = 699 comparisons), but the 18 taxa could be further classified into three categories by the direction of the effect size: taxa whose log concentrations did not differ significantly from the controls (category 1), taxa whose log concentrations increased significantly with DFM supplementation (category 2), and taxa whose log concentrations decreased significantly with DFM supplementation (category 3). Category 1 comprised nine taxa, including total bacterial counts. Category 2 comprised four taxa: Bacillus, Bifidobacterium, Clostridium butyricum, and Lactobacillus. Category 3 comprised five taxa: Clostridium perfringens, coliforms, Escherichia coli, Enterococcus, and Salmonella. Some characteristics identified by the subgroup analysis were associated with result heterogeneity. Most studies, however, were present with unclear risk of bias. Publication bias was also identified. CONCLUSION: DFM supplementation increased the concentrations of some beneficial bacteria (e.g. Bifidobacterium and Lactobacillus) and decreased those of some detrimental bacteria (e.g. Clostridium perfringens and Salmonella) in the guts of broiler chickens.

Chromosome Abnormalities and Absolute Telomere Lengths of Leukocytes from Silk Weavers with Emphasis on Potential Genotoxicity and Mutagenicity of Silk Dyes

Objectives: This study is aimed to assess the possible genotoxicity and mutagenicity of silk dyes on silk weavers. Methods: Peripheral blood leukocytes were obtained from 24 silk weavers and 24 age- and sex-matched controls in northeastern Thailand. After mitogen stimulation in culture, chromosome abnormalities were examined using Giemsa banding and the absolute telomere length (aTL) was measured with SYBR green qRT-PCR. To confirm genotoxic and mutagenic effects of silk dyes, leukocytes from one each of healthy male and female volunteers were cultured with various concentrations of 3 dark red silk dyes under the presence of mitogen. Chromosome abnormalities and the telomere length were determined as above. Results: The proportion of normal metaphase in the silk weaving workers was significantly lower than that in controls. The frequency of chromosome aberrations was higher in the silk weavers than in control group. Polyploidy was detected only in the silk weavers. The aTL was significantly shorter in the silk weavers than in control group (p < 0.05). When leukocytes from normal volunteers were stimulated with mitogen under the presence of various concentrations of 3 silk dyes, suppressed the mitotic index (MI) and normal metaphase, whereas the proportion of prophase and the incomplete chromosome forming increased significantly. All dyes induced polyploidy. Dye #CA5 induced structural changes in male leukocytes, whereas #30 induced the changes in female leukocytes. The #CA5 increased aTL of normal leukocytes in a dose-dependent manner. Conclusions: All dyes, especially #CA5, have high genotoxicity and mutagenicity to induce chromosome aberrations and telomeric instability. Taken all those results together, regular health checking of silk weavers who have been exposed to those dyes is critically necessary to prevent various chemical-induced carcinogenesis.

Neutralizing formaldehyde in chicken cadaver with urea and urea fertilizer solution.

This study demonstrated the potential of using urea and urea fertilizer to neutralize formaldehyde (Fd) in chicken cadavers. Initially, in vitro Fd neutralization with various concentrations of urea solution (US) and urea fertilizer solution (UFS) was conducted; subsequently, 18% US and 27% UFS were selected for infusing into the formalinized chickens. The measurement at 48 hr after infusion showed that both solutions could effectively lower Fd in chicken cadavers to below a permissible exposure limit without affecting cadaveric and histological quality. In addition, neutralizing power of 18% US was approximately 1.3 times that of 27% UFS. This is the first demonstration of neutralizing potential of US and UFS against Fd both in vitro and in vivo.