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91.
Background:Metabolomic approaches,which include the study of low molecular weight molecules,are an emerging-omics technology useful for identification of biomarkers.In this field,nuclear magnetic resonance(NMR)spectroscopy has already been used to uncover(in)fertility biomarkers in the seminal plasma(SP)of several mammalian species.However,NMR studies profiling the porcine SP metabolome to uncover in vivo fertility biomarkers are yet to be carried out.Thus,this study aimed to evaluate the putative relationship between SPmetabolites and in vivo fertility outcomes.To this end,24 entire ejaculates(three ejaculates per boar)were collected from artificial insemination(AI)-boars throughout a year(one ejaculate every 4 months).Immediately after collection,ejaculates were centrifuged to obtain SP-samples,which were stored for subsequent metabolomic analysis by NMR spectroscopy.Fertility outcomes from 1525 inseminations were recorded over a year,including farrowing rate,litter size,stillbirths per litter and the duration of pregnancy.Results:A total of 24 metabolites were identified and quantified in all SP-samples.Receiver operating characteristic(ROC)curve analysis showed that lactate levels in SP had discriminative capacity for farrowing rate(area under the curve[AUC]=0.764)while carnitine(AUC=0.847),hypotaurine(AUC=0.819),sn-glycero-3-phosphocholine(AUC=0.833),glutamate(AUC=0.799)and glucose(AUC=0.750)showed it for litter size.Similarly,citrate(AUC=0.743),creatine(AUC=0.812),phenylalanine(AUC=0.750),tyrosine(AUC=0.753)and malonate(AUC=0.868)levels had discriminative capacity for stillbirths per litter;and malonate(AUC=0.767)and fumarate(AUC=0.868)levels for gestation length.Conclusions:The assessment of selected SP-metabolites in ejaculates through NMR spectroscopy could be considered as a promising non-invasive tool to predict in vivo fertility outcomes in pigs.Moreover,supplementing AI-doses with specific metabolites should also be envisaged as a way to improve their fertility potential.  相似文献   
92.
A greenhouse experiment was conducted to investigate the effects of different culture media on plantlet emergence, vegetative and generative traits of Marigold (Calendula officinalis) in randomized complete block design with ten treatments and three replications. The treatments were consisted of spent mushroom compost (SMC), alluvium soil (AS), garden soil (GS), SMC + AS (2:1), SMC + GS (2:1), SMC + AS (1:2), SMC + GS (1:2), AS + GS (2:1), GS + AS (2:1) and SMC + AS + GS (1:1:1). The results showed that application of SMC had positive effects on the vase life of flower and the number of days from the first bloom appearance. The vase life of flower was the highest (17.4 days) in the media containing SMC alone and the shortest (12.3 days) in media containing SMC + AS (1:2). However, mixture of SMC with AS or GS had significant positive effects on the evaluated traits. Generally, AS, SMC + AS or GS (2:1) and GS treatments had a better situation than other media.  相似文献   
93.
Leishmania infantum is a protozoan parasite causing leishmaniosis, a visceral disease transmitted by the bites of sand flies. As the main reservoir of the parasite, dogs are the principal targets of control measures against this disease, which affects both humans and dogs. Several studies have revealed the usefulness of topical insecticide treatment (collars, spot-ons and sprays) in reducing the incidence and prevalence of L. infantum. The present study was designed to test the efficacy of 65% permethrin applied to dogs as a spot-on against the sand fly vector Phlebotomus perniciosus. The duration of the desired effects was also estimated to help design an optimal treatment regimen. Twelve dogs assigned to treatment (n=6) and control (n=6) groups were exposed to sand flies once a week over a seven-week period. Repellent and insecticidal efficacies were estimated and compared amongst the groups. Our findings indicate satisfactory repellent, or anti-feeding, effects lasting 3 weeks and short-term insecticidal effects lasting 2 weeks after initial application. Accordingly, we recommend the use of this product every 2-3 weeks during the active phlebotomine sand fly period to protect dogs against the bites of P. perniciosus.  相似文献   
94.
In jute (Corchorus olitorius), quantitative trait loci (QTL) analysis was conducted to study the genetics of eight fibre yield traits and two fibre quality traits. For this purpose, we used a mapping population consisting of 120 recombinant inbred lines (RILs) and also used a linkage map consisting of 36 SSR markers that was developed by us earlier (Das et al. 2011). The RIL population was derived from the cross JRO 524 (coarse fibre) × PPO4 (fine fibre) following single seed descent. Using single-locus analysis involving composite interval mapping, a total of 21 QTLs were identified for eight fibre yield traits whereas for fibre quality (fibre fineness), only one QTL was detected. The QTL for fibre fineness explained 8.31–10.56% of the phenotypic variation and was detected in two out of three environments. Using two-locus analysis involving QTLNetwork, as many as 11 M-QTLs were identified for seven fibre yield traits (excluding top diameter) and one M-QTL was identified for fibre fineness which accounted for 4.57% of the phenotypic variation. For six fibre yield traits, we detected 16 E-QTLs involved in nine QQ epistatic interactions. For fibre fineness, four E-QTLs involved in two QQ epistatic interactions and for fibre strength, six E-QTLs involved in three QQ epistatic interactions were identified. Eight out of the 11 M-QTLs observed for the fibre yield traits were also involved in QE interactions; for fibre fineness and fibre strength, no QE interactions were observed.  相似文献   
95.
Leishmaniasis by Leishmania infantum in the Mediterranean Basin constitutes an important problem in both human and veterinary medicine. Based in both the importance of canids as reservoirs for the human disease and the fact that the canine disease may be an excellent model for the human condition, the present work has been conducted to analyze clinical and immune mechanisms associated with canine experimental leishmaniasis. Six-month-old mixed-breed dogs were intravenously infected with L. infantum promastigotes and the infection course was monitored along a 343 days-period. On day 75 post-infection (p.i.), amastigotes were observed in the lymph nodes of all dogs. The analysis of the humoral response against total L. infantum antigens by both ELISA and Western blotting evidenced a correlation between the levels of IgG isotypes (IgG1 and IgG2) and disease progression. It was observed that in those animals showing either a regressive or an oligosymptomatic form of the disease, the anti-Leishmania IgG1 antibodies were undetectable whereas those animals developing active disease showed high levels of anti-Leishmania IgG1 antibodies. Additionally, the time-course of antibody production against L. infantum recombinant antigens in the experimentally infected dogs has been analyzed. The present data suggest that reactivity against the heat-shock protein 70 (HSP70) may be used as diagnostic marker of early steps of infection, and that the appearance of anti-histone antibodies is associated with progression of infection to disease status.  相似文献   
96.
The purpose of this study was to determine basic kinematic parameters (linear, temporal and angular) in young and adult Andalusian horses (P.R.E.) at the trot, using a normal computer-aided videography system. The trotting gaits of 16 horses were analysed: seven young horses (3.7 +/- 0.2 years old, height at withers 167.1 +/- 4.1 cm) and nine adult stallions (12.3 +/- 2.9 years old, height at withers 162.9 +/- 3.6 cm) were recorded at least 6 times at the trot using a 25-Hz video-camera filming from the side. Video images were processed with a real-time digital system (SMVD). Speeds averaged 3.84 and 3.75 m/s for young and adult horses, respectively. Differences between age groups for speed and linear and temporal parameters of the stride were not significant. However, variations in angular parameters were detected: adults showed a greater ARM than younger horses for most forelimb joints. In the hind limb, hip, stifle, and, to a lesser degree, the tarsal joint, a smaller degree of extension during the stance phase was observed in adult horses.  相似文献   
97.
Shiga toxin‐producing Escherichia coli (STEC) are foodborne pathogens that can cause severe diseases, including bloody diarrhoea and kidney failure, in humans, while remaining harmless to its primary reservoir hosts, cattle. Antibiotics such as azithromycin, fosfomycin and meropenem are being used and recommended in the treatment of early‐stage STEC (mainly E. coli O157:H7) infections, as these are reportedly effective in preventing Shiga toxin release and kidney failure while eliminating the pathogen. However, antibiotic resistance among STEC isolates could negatively impact these and other similar treatment options while contributing towards the spread of antibiotic resistance genes especially if encoded on mobile genetic elements like plasmids. Antibiotic resistance among STEC isolates recovered from animals and patients is being reported globally. A comprehensive understanding of the prevalence of antibiotic‐resistant STEC (AR‐STEC) and the mechanisms promoting this resistance among these bacteria could help direct therapies and develop strategies to effectively reduce/eliminate these pathogens. Here, we have reviewed literature from the past three decades to gain insights on this prevalence and its impact on human infections. In addition, we have reviewed various strategies proposed by researchers to control STEC that in turn would be applicable to AR‐STEC as well.  相似文献   
98.
This experiment was conducted to identify the suitable replacer of broiler feed antibiotics with prebiotics (mannan oligosaccharides‐MOS or fructooligosaccharide‐FOS). Two hundred and forty (240)‐day‐old chicks were randomly divided into 30 groups (6 treatments x 5 replicates/treatment x 8 chicks/replicate). Six experimental diets T1, T2, T3, T4, T5 and T6 were formulated to contain an additional 0, antibiotic, that is, bacitracin methylene di‐salicylate (BMD) @20 mg/kg, MOS (0.1% and 0.2%) and FOS (0.1% and 0.2%) respectively. Body weight gain was significantly (p < 0.05) increased in MOS‐0.2% supplemented group at 0–21 d and 0–42 d of broiler chicken. Humoral and in vivo cell‐mediated immune response were significantly improved (p < 0.05) in BMD, MOS @0.1% or 0.2% treated group. Significant (p < 0.05) increase was recorded in total protein (except 21 d), albumin and aspartate amino transferase (AST) and decrease (p < 0.05) in alanine amino transferase (except 42 d), cholesterol and uric acid concentration. The weight of breast, thigh, back, drumstick bursa of Fabricius and thymus were higher (p < 0.05) in the birds given the MOS @0.2% (T4). It is concluded that MOS @0.2% may be suitable replacer of antibiotic growth promoter, and it has a beneficial effect on production performance, immune responses, blood biochemical parameters and cut up parts in broiler chickens.  相似文献   
99.
This study was conducted to evaluate the effects of dietary soapnut (Sapindus mukorossi) shell powder (SSP), a cheap source of saponins, on growth performance, immunity, serum biochemistry and gut health of broiler chickens. The experimental design was 4×2, employing four saponin levels (0, 100, 150 and 200 mg/kg diet), each provided for two time durations (0–42 day and 21–42 day) resulting into eight dietary treatments. Results revealed no significant effect of dietary saponins on body weight gain, feed intake and feed conversion ratio of birds. The abdominal fat percentage, heterophil to lymphocyte ratio, serum cholesterol and triglyceride levels, faecal total plate count, coliform count and E. coli count decreased (p < .05) progressively with increasing saponin levels and lower values were observed at 150 mg and 200 mg saponin levels. Significant improvement of cell‐mediated and humoral immune response was observed in birds fed 150 mg and 200 mg saponin compared to control. The serum glucose concentration was significantly (p < .05) higher in control group compared to other groups. No significant effects of dietary saponin were observed on carcass characteristics, faecal Lactobacillus count, intestinal histomorphometry and cost economics of broiler chicken production. Thus, dietary saponins at 150 mg/kg diet as SSP for three weeks (21–42 days) was optimum for better immunity and welfare of birds without adverse effects on the growth performance.  相似文献   
100.
The present study describes the development of DNA vaccines using the hemagglutinin-neuraminidase (HN) and fusion (F) genes from AF2240 Newcastle disease virus strain, namely pIRES/HN, pIRES/F and pIRES-F/HN. Transient expression analysis of the constructs in Vero cells revealed the successful expression of gene inserts in vitro. Moreover, in vivo experiments showed that single vaccination with the constructed plasmid DNA (pDNA) followed by a boost with inactivated vaccine induced a significant difference in enzyme-linked immunosorbent assay antibody levels (p < 0.05) elicited by either pIRES/F, pIRES/F+ pIRES/HN or pIRES-F/HN at one week after the booster in specific pathogen free chickens when compared with the inactivated vaccine alone. Taken together, these results indicated that recombinant pDNA could be used to increase the efficacy of the inactivated vaccine immunization procedure.  相似文献   
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