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1.
Melanocortin receptor 1 (MC1R) and agouti signaling protein (ASIP) are two major genes affecting coat color phenotypes in mammals, and inactivation mutations in the MC1R gene are responsible for red coat color in European pig breeds. Conversely, the gain‐of‐function ASIP mutations block MC1R signaling and lead to the production of red pheomelanin. Chinese Tibetan pigs have three types of coat color phenotypes, including brownish red, solid black and black with patches of brownish red and white. Herein, we investigated variations of the MC1R and ASIP genes in Tibetan pigs. The results showed that the brownish red Tibet pig had the dominant black MC1R allele (ED1). No loss‐of‐function mutation in MC1R responsible for red coat color in European breeds was observed in this breed. No causal mutation for the red coat color phenotype was found in the coding sequence of the ASIP gene. A novel missense mutation c.157G > A was firstly identified in exon 2 of ASIP, which was further genotyped in 285 pigs from five Chinese breeds and three Western breeds having different coat color phenotypes. Nearly all pigs were GG homozygotes. In conclusion, no functional variant responsible for brownish red coloration was found in the coding region of MC1R and ASIP in Tibetan pigs.  相似文献   

2.
In this paper we describe the use of polymorphic genes affecting coat colour as a tool in diversity studies of domestic animals. Although phenotypic data has been the main criteria for establishing different breeds, calculation of genetic distances between breeds is normally performed using noncoding microsatellite markers. As anticipated, MC1‐R (melanocyte stimulating hormone receptor) allele frequencies vary greatly between cattle breeds expressing different coat colours. In multicoloured breeds, like Icelandic cattle, a high frequency of the E+ allele appears to be essential for colour variation. Whereas black breeds have a high frequency of the dominant acting allele ED, entirely red breeds have no ED. Animals being homozygous for the defective allele e occurred frequently in some cattle breeds, indicating that the MC1‐R does not have crucial impact on animal physiology other than coat colour. The E+ and e alleles were observed in the closely related river buffalo as well. None of the breeds included in this study express the roan phenotype. Consequently, they were monomorphic at the MGF locus. As for the MC1‐R locus, a correlation to colour pattern was observed for two c‐kit alleles as well, confirming that selection of specific phenotypes strongly affect the allelic variation of underlying loci. Information on genes affecting the phenotype is therefore well suited for describing different breeds of livestock and, consequently, a practical tool in breed conservation.  相似文献   

3.
Orosomucoid polymorphisms influence plasma drug binding in humans; however, canine variants and their effect on drug plasma protein binding have not yet been reported. In this study, the orosomucoid gene (ORM1) was sequenced in 100 dogs to identify the most common variant and its allele frequency determined in 1,464 dogs (from 64 breeds and mixed‐breed dogs). Plasma protein binding extent of amitriptyline, indinavir, verapamil, and lidocaine were evaluated by equilibrium dialysis using plasma from ORM1 genotyped dogs (n = 12). Free and total drug plasma concentrations were quantified by liquid chromatography–mass spectrometry. From the five polymorphisms identified in canine ORM1, two were nonsynonymous. The most common was c.70G>A (p.Ala24Thr) with an allele frequency of 11.2% (n = 1464). Variant allele frequencies varied by breed, reaching 74% in Shetland Sheepdogs (n = 21). Free drug fractions did not differ significantly (p > .05; Mann‐Whitney U) between plasma collected from dogs with c.70AA (n = 4) and those with c.70GG (n = 8) genotypes. While c.70G>A did not affect the extent of plasma protein binding in our study, the potential biological and pharmacological implication of this newly discovered ORM1 variant in dogs should be further investigated.  相似文献   

4.
In this study, we investigated whether a selection programme based on boar genetic evaluation obtained with a classical BLUP animal model can change allele frequencies in a pig population. All Italian Large White boars born from 1992 to 2012 with estimated breeding value reliability >0.85 (n = 200) were selected among all boars of this breed. Boars were genotyped with markers in major genes (IGF2 intron3‐g.3072G>A, MC4R p.D298N, VRTN PRE1 insertion, PRKAG3 p.I199V and FTO g.276T>G). Genotyping data were analysed grouping boars in eight classes according to their year of birth. To evaluate the influence of time on allele frequencies of the genotyped markers, multinomial logistic regression models were computed. Four of five polymorphic sites (IGF2, MC4R, VRTN and FTO) showed significant (p < 0.01) changes in allele frequencies over time due to a progressive and continuous increase of one allele (associated with higher lean meat content, higher average daily gain and favourable feed: gain ratio) and, consequently, decrease of the other one, following the directional selection of the selection programme of this pig breed. The retrospective analysis that was carried out in Italian Large White boars suggests that selection based on methodologies assuming the infinitesimal model is able to modify in a quite short period of time allele frequencies in major genes, increasing the frequency of alleles explaining a relevant (non‐infinitesimal) fraction of the overall genetic variability for production traits.  相似文献   

5.
In order to estimate the influence of TYR and MC1R on the color of the cattle hide, the MC1R and TYR in Luxi Yellow, Bohai Black, China Holstein black‐white and China Holstein red‐white cattle (20 animals of each of the four breeds) were sequenced. The comparison of TYR among the four hide color phenotypes revealed no sequence difference. The sequences of the MC1R coding region revealed three alleles (ED, E+ and e), which were previously reported. Furthermore, we found an important single nucleotide polymorphism at 725 position of the MC1R coding region, which may help in cattle breed identification. A polymerase chain reaction‐restriction fragment length polymorphism was performed to investigate the gene frequencies of the four breeds. Most China Holstein black‐white cattle had ED and E+ alleles (ED = 0.12, E+ = 0.80) and no homozygous e/e and most Bohai Black cattle had ED and E+ alleles (ED = 0.52, E+ = 0.47). Therefore it is consistent with the hypothesis that ED and E+ induce black pigment synthesis. On the other hand, most of the China Holstein red‐white cattle and Luxi Yellow cattle had the e allele (e/e = 0.95). Unexpectedly, the E+/e genotype was present in China Holstein red‐white cattle and Luxi Yellow cattle.  相似文献   

6.
In recent years, intensive attention has been put on improving reproductive performance of pigs. Several experiments aimed to identify markers associated with prolificacy, but this issue still remains open. In our study, we investigated associations between polymorphisms in IGF2, GNAS and MC4R genes with reproductive traits of Polish Landrace and Large White pigs. We did not find any significant associations for g. GNAS314T > 324C, IGF2 intron3‐g.3072G > A or g. MC4R 1426G > A in Polish Landrace and Large White pigs. In the case of IGF2 intron3‐g.3072G > A, this information is of great importance, because this marker is widely implemented in pigs breeding and previous experiments suggested its role in prolificacy of pigs. We also investigated expression of IGF2 gene and showed that this gene is monoallelically expressed in reproductive organs (ovary and cornus uteri).  相似文献   

7.
We present here the first genome‐wide characterization of linkage disequilibrium (LD) in the French Blonde d'Aquitaine (BLA) breed, a well‐muscled breed renowned for producing high‐yielding beef carcasses. To assess the pattern and extent of LD, we used a sample of 30 unrelated bulls and 36 923 single nucleotide polymorphisms (SNPs) covering all cattle autosomes. The squared correlation of the alleles at two loci (r2) was used as a measure of LD. The analysis of adjacent marker pairs revealed that the level of LD decreases rapidly with physical distance between SNPs. Overall mean r2 was 0.205 (±0.262). Strong LD (r2 > 0.8) and useful LD (measured as r2 > 0.2) were observed within genomic regions of up to 720 and 724 kb, respectively. We analysed the genetic structure of the BLA population and found stratification. The observed genetic sub‐structuring is consistent with the known recent demographic history that occurred during BLA breed formation. Our results indicate that LD mapping of phenotypic traits in the BLA population is feasible; however, because of this sub‐structuring, special care is needed to reduce the likelihood of false‐positive associations between marker loci and traits of interest.  相似文献   

8.
Here, we describe the establishment of mutant‐specific polymerase chain reaction (PCR) for detection of a c‐KIT c.1430G>T mutation in feline mast cell tumours. Several mutations in feline c‐KIT have been identified, with the c.1430G>T mutation accounting for a significant portion of feline mast cell tumour mutations. The c.1430G>T mutation in c‐KIT exon 9 was detected in 15.7% (11 of 70) of samples by mutant‐specific PCR but in only 7.1% (5 of 70) by PCR–restriction fragment length polymorphism (RFLP) in the genomic DNA isolated from 70 formalin‐fixed paraffin‐embedded sections or cells collected by fine needle aspiration. Mutant‐specific PCR showed remarkably higher detection rate than did PCR–RFLP. DNA sequence analysis did not always yield identical results to those of mutant‐specific PCR, suggesting heterogeneity of tumour cells. Mutant‐specific PCR is a valid and efficient screening tool for detection of the c‐KIT c.1430G>T point mutation in feline mast cell tumours compared with PCR–RFLP and sequencing analysis.  相似文献   

9.
In this article, we investigated the genetic variations in the coding region of porcine melanocortin receptor 1 (MC1R) gene in three pig breeds (Min, Yorkshire and Landrace) with black and white coat colors. Six polymorphic sites were found to be significantly associated with coat color. Two blocks were identified in the linkage disequilibrium map, the haplotypes in the first block are nt67/68indelCC and nt67/68indel--, and the haplotypes in the second block are ACCGA and GTTAG. The median-joining network diagram of MC1R haplotypes showed most Min pigs and other Asia domestic breeds own similar haplotypes to ACCGA, while the haplotypes of Europe pig breeds are similar to GTTAG. The phylogenetic analysis of the MC1R CDS further showed Min pigs are close to Laiwu pigs (Shandong, China), which indicated that the black coat color trait of Min pig might be originated and evolved from the black pig breed in Shandong Peninsula of China.  相似文献   

10.
Variation at the porcine DECR1 and ME1 genes has been associated with meat quality traits and backfat thickness in Landrace pigs, respectively. However, it has not been investigated yet whether DECR1 and ME1 genotypes influence lipid composition. With this aim, we have genotyped two missense DECR1 substitutions (c.160G>C and c.437G>C) and one silent ME1 (c.576C>T) polymorphism in 361 Duroc barrows distributed in five half‐sib families and phenotyped for serum lipid concentrations and intramuscular fat content and composition traits. At the whole‐population level, relevant associations, that is, with a posterior probability of the allele substitution effect to be over or below zero (PPN0) > 0.90, were observed between DECR1 genotype and serum cholesterol (CHOL) (PPN0 = 0.932) and LDL concentrations (PPN0 = 0.945) at 190 days, as well as between ME1 genotype and longissimus dorsi saturated fatty acid content (PPN0 = 0.924). At the within‐family level, we found relevant associations between DECR1 and ME1 genotypes and diverse lipid composition traits, but most of them were family‐specific. Discrepancies in allele substitution effects estimated in half‐sib families might be produced by many factors such as number of individuals, marker allele frequencies and informativeness in each family, unaccounted random genetic and environmental effects, epistasis and family‐specific differences in the linkage phase or amount of linkage disequilibrium between causal and marker mutations. This lack of consistency across families, combined with the fact that the ME1 mutation is synonymous and that the two DECR1 polymorphisms are conservative, suggests that the associations found are not causative.  相似文献   

11.
Melanocortin 4 receptor (MC4R) plays a key role in controlling energy homeostasis. Several studies have already reported effects on production traits of polymorphisms identified in the porcine MC4R gene. In this study we analysed data on 6 MC4R polymorphisms (c.-780C>G; c.-135C>T; c.175C>T; c.707G>A or p.Arg236His; and c.892G>A or p.Asp298Asn; c.?430A>T) genotyped from (1) two groups of Italian Large White pigs (280+280 animals) with extreme estimated breeding values (EBVs) for back fat thickness (BFT), selected among a performance tested population of about 12,000 pigs, and from (2) 19 Italian Duroc pigs. Two haplotypes, differentiated by the c.892G>A, were identified in the Duroc populations. Four haplotypes were identified in the Italian Large White population, one of which (haplotype 4) was identified for the first time in this study. Single marker and haplotype association analyses for BFT were obtained by comparing allele and haplotype frequency differences from the two extreme tails using χ2 and Cochran–Armitage trend tests. Results confirmed the effects of the c.892G>A single nucleotide polymorphism (SNP) on BFT, as also defined by different distributions in the two tails of haplotypes carrying the alternative nucleotides at this polymorphic site (P<0.01). In addition different distributions of haplotype 4 in the two extreme groups suggested that it might affect the same trait (P<0.10). Association analyses for several other traits (average daily gain, ADG; feed gain ratio, FGR; weight of lean cuts; ham weight) were carried out by using EBVs and Random Residuals: significant effects (P<0.05) were only found for the p.Asp298Asn mutation on ADG and FGR. Results did not support any relevant effect of the p.Arg236His mutation on any trait. Data reported in this study contribute to better understand the role of MC4R variants in affecting production traits in pigs, a prerequisite to consider polymorphisms in this gene for marker assisted selection.  相似文献   

12.
Increase in the number of small‐scale backyard poultry flocks in the USA has substantially increased human‐to‐live poultry contact, leading to increased public health risks of the transmission of multi‐drug resistant (MDR) zoonotic and food‐borne bacteria. The objective of this study was to detect the occurrence of Salmonella and MDR Gram‐negative bacteria (GNB) in the backyard poultry flock environment. A total of 34 backyard poultry flocks in Washington State (WA) were sampled. From each flock, one composite coop sample and three drag swabs from nest floor, waterer‐feeder, and a random site with visible faecal smearing, respectively, were collected. The samples were processed for isolation of Salmonella and other fermenting and non‐fermenting GNB under ceftiofur selection. Each isolate was identified to species level using MALDI‐TOFF and tested for resistance against 16 antibiotics belonging to eight antibiotic classes. Salmonella serovar 1,4,[5],12:i:‐ was isolated from one (3%) out of 34 flocks. Additionally, a total of 133 ceftiofur resistant (CefR) GNB including Escherichia coli (53), Acinetobacter spp. (45), Pseudomonas spp. (22), Achromobacter spp. (8), Bordetella trematum (1), Hafnia alvei (1), Ochrobactrum intermedium (1), Raoultella ornithinolytica (1), and Stenotrophomonas maltophilia (1) were isolated. Of these, 110 (82%) isolates displayed MDR. Each flock was found positive for the presence of one or more CefR GNB. Several MDR E. coli (n = 15) were identified as extended‐spectrum β‐lactamase (ESBL) positive. Carbapenem resistance was detected in non‐fermenting GNB including Acinetobacter spp. (n = 20), Pseudomonas spp. (n = 11) and Stenotrophomonas maltophila (n = 1). ESBL positive E. coli and carbapenem resistant non‐fermenting GNB are widespread in the backyard poultry flock environment in WA State. These GNB are known to cause opportunistic infections, especially in immunocompromised hosts. Better understanding of the ecology and epidemiology of these GNB in the backyard poultry flock settings is needed to identify potential risks of transmission to people in proximity.  相似文献   

13.
ESBL/AmpC‐producing Escherichia coli is increasingly isolated from humans and animals worldwide. The occurrence of ESBL/AmpC‐producing E. coli was studied in food‐producing animals in Finland, a country with a low and controlled use of antimicrobials in meat production chain. A total of 648 cattle, 531 pig, 495 broiler and 35 turkey faecal samples were collected from four Finnish slaughterhouses to determine the presence of extended‐spectrum β‐lactamase (ESBL/AmpC)‐producing E. coli. In addition, 260 broiler and 15 turkey samples were screened for carbapenemase‐producing E. coli. Susceptibility to different class of cephalosporins and meropenem was determined with disc diffusion tests according to the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Determination of ESBL/AmpC production was performed with a combination disc diffusion test according to the recommendations of the European Food Safety Authority (EFSA). Plasmidic blaESBL/AmpC genes were characterized by polymerase chain reaction and sequencing. A collection of isolates producing AmpC enzyme but not carrying plasmidic blaAmpC was analysed by PCR and sequencing for possible chromosomal ampC promoter area mutations. Altogether ESBL/AmpC‐producing E. coli was recovered from five cattle (0.8%), eight pig (1.5%) and 40 broiler samples (8.1%). No ESBL/AmpC‐producing E. coli was found in turkey samples. Carbapenem resistance was not detected. Altogether ESBL/AmpC‐producing E. coli was found on 4 (2.0%), 3 (4.5%) and 14 (25%) cattle, pig and broiler farms, respectively. From cattle samples 3 (27%) blaCTX‐M‐1 and from broiler samples 13 (33%) blaCTX‐M‐1 and 22 (55%) blaCMY‐2 gene‐carrying isolates were detected. In pigs, no plasmidic blaESBL/AmpC gene‐carrying isolates were found. In all analysed isolates, the same mutations in the promoter region of chromosomal ampC were detected. The results showed low occurrence of ESBL/AmpC‐producing E. coli in Finnish food‐producing animals. In pigs, plasmidic blaESBL/AmpC‐carrying E. coli was not detected at all.  相似文献   

14.
In order to estimate the influence of the Extension (E) locus in cattle coat color, the melanocortin‐1 receptor (MC1R) gene in Japanese Black, Japanese Brown and Korean (Hanwoo) cattle were sequenced. The sequences of the coding region revealed three alleles (ED, E+ and e), which were previously reported. Polymerase chain reaction‐restriction fragment length polymorphism was performed to investigate the gene frequencies of the three breeds. Japanese Black was almost composed of ED and E+ individuals, ED = 0.481 and E+ = 0.514, and no homozygous e/e, therefore that is consistent with the hypothesis that ED and E+ induce black pigment synthesis. Allele frequencies between Japanese Brown and Hanwoo were obviously different; however, recessive red e allele frequency was 0.038 for Japanese Brown and 0.948 for Hanwoo, even though both breeds have quite similar coat colors (ranging from yellowish brown to dark brown including a red coat color). This result suggested that other genes are also associated with a coat color of red and brown in cattle.  相似文献   

15.
In our previous study, we detected a QTL for the oleic acid percentage (C18:1) on BTA9 in Japanese Black cattle through a genome‐wide association study (GWAS). In this study, we performed whole‐genome resequencing on eight animals with higher and lower C18:1 to identify candidate polymorphisms for the QTL. A total of 39,658 polymorphisms were detected in the candidate region, which were narrowed to 1993 polymorphisms within 23 genes based on allele differences between the high and low C18:1 groups. We subsequently selected three candidate genes, that is, CYB5R4, MED23, and VNN1, among the 23 genes based on their function in fatty acid metabolism. In each candidate gene, three SNPs, that is, CYB5R4 c.*349G > T, MED23 c.3700G > A, and VNN1 c.197C > T, were selected as candidate SNPs to verify their effect on C18:1 in a Japanese Black cattle population (n = 889). The statistical analysis showed that these SNPs were significantly associated with C18:1 (p < 0.05), suggesting that they were candidates for the QTL. In conclusion, we successfully narrowed the candidates for the QTL by detecting possible polymorphisms located within the candidate region. It is expected that the responsible polymorphism can be identified by demonstrating their effect on the gene's function.  相似文献   

16.
This study was conducted to examine the effects of weaning stress on gene expression of specific markers in hypothalamus‐pituitary‐adrenal (HPA) axis and neuronal activity in the newly weaned piglets. Twelve 28‐days‐old, newly weaned crossbred (Landrace × Yorkshire × Duroc) male piglets from 6 l (2 piglets/l) were randomly categorized into two groups: (a) weaning stress: piglets were separated from their dams, relocated and mixed with the unacquainted domestic piglets for 2 hr (stress, n = 6); (b) no‐stress: piglets stayed with their dams in the farrowing house (NS; n = 6). After weaning stress, all piglets were electrically euthanized and the blood samples/HPA tissues were collected for subsequent analysis, including plasma cortisol and mRNA expression of c‐fos, c‐jun, corticotropin‐releasing hormone (CRH), CRH receptor 1 (CRHR‐1) and adrenocorticotropin hormone receptor (MC2R). Results: Weaning stress significantly (p < 0.05) increased the plasma cortisol level and suppressed the expression of c‐fos and CRH in hypothalamus. In addition, weaning stress enhanced the mRNA abundance of c‐jun and CRHR‐1 in the pituitary gland. No significant differences in the gene expression of MC2R and CRHR‐1 were observed in the adrenal gland between treatment groups. Taken together, HPA involved in weaning stress and CRHR‐1 and c‐jun could be potential markers to evaluate the activation of HPA axis.  相似文献   

17.
Prolificacy is an important trait of animals, specifically for sheep. The Bone morphogenetic protein receptor 1B (BMPR1B) is a major gene affecting the litter size of many sheep breeds. The well-known FecB mutation (Q249R) was associated fully with the hyper prolific phenotype of Booroola Merino. However, the identification of variation in all exonic regions of BMPR1B was rare. In this study, we sequenced all exonic regions of BMPR1B gene of Mongolia sheep breed, and ten novel variants were detected by direct sequencing. Among them, the litter size of the Mongolia ewes with the CC genotype was significantly higher (0.34 additional lambs, p < .05) than those with the TT genotype of the g.29346567C>T single nucleotide polymorphism (SNP). The litter size of the Mongolia ewes with the TT genotype was significantly higher (0.19 additional lambs, p < .05 and .31 additional lambs, p < .01, respectively) than those with the GT and GG genotypes of the c.1470G>T SNP. The silent c.1470G>T mutation is predicted to increase the stability of the mRNA secondary structure through reducing minimum free energy and is predicted to change the mRNA secondary structure of BMPR1B. Our findings may give potentially useful genetic markers for increasing litter size in sheep.  相似文献   

18.
The GMM sheep is a carrier of Booroola fecundity (FecB) gene, which produces the twins and triplets in one lambing. The homozygous carrier GMM (FecBBB), non‐carrier GMM and Malpura (FecB++) ewes were synchronized by progesterone sponges, and the plasma progesterone concentration was measured by RIA. The results showed that the progesterone concentration did not differ significantly (p > .05) in homozygous carrier GMM (5.74 ± 1.2 ng/ml), non‐carrier GMM (5.42 ± 1.4 ng/ml) and non‐carrier Malpura ewes (5.67 ± 1.5 ng/ml). Further, quantitative expression of BMP factors/receptors and SMAD signalling genes were analysed in the ovaries of sheep by qRT‐PCR. The study showed that the expression of BMP2 was slightly higher (p > .05) in carrier GMM than that of non‐carrier GMM, but it was almost similar to Malpura ewes. Expression of BMP4 and BMP7 was significantly higher (p < .001; p < .05) in carrier GMM than that of non‐carrier GMM and Malpura ewes. Although BMP6 expression was higher (p > .05) in carrier GMM than that of non‐carrier GMM, but lower (p > .05) than the Malpura ewes. Expression of BMP15 (p < .05), GDF5 (p < .01) and GDF9 (p < .05) was significantly higher in carrier GMM than non‐carrier GMM ewes. Surprisingly, BMPR1B expression was significantly higher (p < .001) in non‐carrier GMM and Malpura than the carrier GMM ewes, while TGFβRI did not differ significantly (p > .05) among both GMM genotypes. On the other hand, expression of BMPR1A (p > .05) and BMPRII (p < .05) was higher in carrier GMM than the non‐carrier GMM, but significantly lower (p < .001) than the Malpura ewes. It was interesting to note that the expression of SMAD1 (p > .05), SMAD2 (p < .001), SMAD3 (p < .05), SMAD4 (p < .001), SMAD5 (p < .001) and SMAD8 (p < .001) was lower in the carrier GMM than that of non‐carrier GMM ewes. It is concluded that the FecB mutation alters the expression of BMPR1B and SMAD signalling genes in the ovaries of homozygous carrier GMM ewes.  相似文献   

19.
This study aimed to investigate the effect of dietary supplementation with Lactobacillus plantarum and Bacillus subtilis on growth performance, apparent nutrient digestibility and stress‐related indicators in dairy calves. Twenty‐four neonatal Holstein calves were randomly allocated to three treatments: a basal diet with no supplementation (control), the basal diet supplemented with 1.7 × 1010 CFU per head per day (CFU/h.d) of L. plantarum GF103 (LB group) or the basal diet supplemented with a mixture of L. plantarum GF103 (1.7 × 1010 CFU/h.d) and B. subtilis B27 (1.7 × 108 CFU/h.d) (LBS group). Dry matter intake (DMI), average daily gain (ADG), feed conversation ratio (FCR), apparent digestibility of nutrients and stress‐related indicators were measured in this trail. The result indicated that no significant differences were observed in DMI or ADG (p > 0.05), but the FCR was improved in the LB group over the first 12 weeks (p > 0.05). The apparent digestibility of nutrients was not altered by probiotics in week 6 (p > 0.05), but the apparent digestibility of total phosphorus was significantly greater in the LB and LBS groups in week 8 (p > 0.05); additionally, an increase in the apparent digestibility of crude protein was detected in the LBS group (p > 0.05). Oral administration of L. plantarum alone improved the T‐lymphocyte transformation rate on days 58 and 62 (p > 0.05), while adding the mixture of L. plantarum and B. subtilis increased the T‐lymphocyte transformation rate (p > 0.05) but decreased the content of cortisol on day 58 (p > 0.05). No significant differences were detected between the LB and LBS groups in growth performance, apparent digestibility of nutrients and stress‐related indicators (p > 0.05). The results suggested that oral administration of L. plantarum improved growth performance, nutrient digestibility and relieved weaning stress in calves, but no additional effect was obtained by supplementation with B. subtilis.  相似文献   

20.
We investigated the prevalence of Hepatitis E Virus (HEV), Leptospira and Ascaris suum (A. suum) seropositivity, and of nasal methicillin‐resistant Staphylococcus aureus (MRSA) colonization among Austrian practising veterinarians, and assessed the association with occupational swine livestock exposure. The 261 participants completed a questionnaire on demographics, intensity of occupational swine livestock contact and glove use during handling animals and their secretions. Participants' blood samples were tested for HEV, Leptospira and A. suum seropositivity and nasal swabs cultured for MRSA. We compared swine veterinarians (defined as >3 swine livestock visits/week) to non‐swine veterinarians (≤3 swine livestock visits/week) with regard to the outcomes through calculating prevalence ratio (PR) and 95% confidence interval (CI). Furthermore, the relationship between occupational swine livestock contact and the study outcomes was examined by age (</≥55 years) and glove usage. The prevalence of nasal MRSA colonization was 13.4% (95% CI: 9.3–17.6), of HEV seropositivity 20.8% (95% CI: 15.8–25.7) and A. suum seropositivity 44% (95% CI: 37.7–50.2). The highest anti‐leptospiral antibodies titres were 1:200 (L. hebdomadis) and 1:100 (L. autumnalis, L. caicola) found in three non‐swine veterinarians. Compared to non‐swine veterinarians, swine veterinarians were 1.9 (95% CI: 1.0–3.4) and 1.5 (95%CI: 1.0–2.3) times more likely HEV seropositive and A. suum seropositive, respectively, and 4.8 (95%CI: 2.5; 9.3) times more likely nasally colonized with MRSA. Among glove‐using veterinarians, occupational swine contact was no longer a determinant for HEV seropositivity (PR 1.6; 95% CI: 0.8–2.9). Similar was found for A. suum seropositivity, which was no longer associated with occupational swine livestock contact in the subgroup of glove using, ≥55‐year‐old veterinarians (PR: 1.07; 95% CI: 0.4–3.3). Our findings indicate that >3 occupational swine livestock visits per week is associated with HEV and A. suum seropositivity and nasal MRSA colonization and that glove use may play a putative preventive role in acquiring HEV and A. suum. Further analytical epidemiological studies have to prove the causality of these associations.  相似文献   

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