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1.
This study reports the status of the Booroola (FecB) and Galway (FecXG) mutations in Indian sheep breeds. The Kendrapada sheep (n = 46) was genotyped for the presence of FecB and FecXG mutations, while the Garole (n = 34), Malpura (n = 30), and Decanni sheep (n = 15) for the FecXG mutation. The FecB and FecXG genotyping was carried out by forced restriction fragment length polymorphism PCR technique. In the present study, FecB mutation was discovered in the Kendrapada sheep of Orissa, which is now the second prolific sheep of India after the Garole. Out of 46 individuals of Kendrapada sheep, 26 were homozygous (BB), 15 heterozygous (B+) and 5 non-carriers (++) for the FecB mutation. The frequency of the FecB allele in this sample was about 0.73. Results indicated that the frequency of the FecB mutation is high, but the gene is not fixed in the population as reported in Garole sheep. None of sheep breeds carried the FecXG mutation. The discovery of the FecB mutation in Kendrapada sheep will facilitate the use of FecB allele in improving the prolificacy of non-prolific sheep breeds of India.  相似文献   

2.
《Small Ruminant Research》2010,91(1-3):11-17
Isoelectric focusing (IEF) was applied for screening milk protein variants in milk samples from altogether 1078 sheep of different breeds, in detail Black Faced Mutton sheep (SKF; n = 57), East Friesian Milk sheep (OMS; n = 254), Gray Horned Heath (GGH; n = 190), Merinoland sheep (MLS; n = 363), Merino Mutton sheep (MMS; n = 88), and Rhön sheep (RHO; n = 126). Besides the known genetic variants of αs1-casein (CSN1S1) (A, C, D), αs2-casein (CSN1S2) (A, B), and β-lactoglobulin (LGB) (A, B, C) additional variants could be demonstrated in CSN1S1 (H, I) and CSN1S2 (C, D) and their genetic control confirmed by segregation analyses. CSN1S1*H corresponds to a previously mentioned phenotype “X” occurring in OMS, whereas CSN1S1*I was identified for the first time in GGH. CSN1S2*C appeared in OMS, GGH, MLS, and RHO in low frequencies and CSN1S2*D in MLS. Within LGB all three alleles occurred in Merino breeds while α-lactalbumin (LAA) and κ-CN (CSN3) were monomorph at protein level. The haplotype CSN1S1*CCSN1S2*A was predominant in five out of six breeds with frequencies between 0.325 and 0.919.  相似文献   

3.
《Small Ruminant Research》2008,80(2-3):146-151
Susceptibility to scrapie in sheep is largely influenced by four polymorphic amino acid positions of the ovine PrP gene at codons 136, 141, 154 and 171. Genotyping of corresponding DNA polymorphism can be used as a basis for selection decisions. A total of 100 Red Maasai and 79 Black Herd Persian sheep, representative of the widely distributed breeds in Tanzania, were genotyped by real-time PCR. Genomic DNA was extracted from buccal epithelial cells. We report six genotypes derived from four different alleles, with the ARQ/ARQ genotype being more frequent (p = 0.0081) in the Red Maasai than in the Black Head Persian sheep. Our study also demonstrated higher allelic frequency (p = 0.00055) of the ARQ in the Red Maasai than in Black Head Persian sheep, while the AHQ allelic frequency was higher (p = 0.00086) in the Black Head Persian. All the animals were homozygous LL141. The highly susceptible VRQ allele was not found in any of the sheep breeds examined in this study. Both breeds were genetically low-level resistant to scrapie (NSP3). Due to absence or very low frequency of the ARR allele in the two breeds, selection for genetic resistance to scrapie through an increase of the ARR allele does not seem very relevant. If new breeds of sheep are to be introduced for crossbreeding in Tanzania, care should be taken to avoid import of the VRQ allele. To our knowledge, this is the first study exploring the PrP genotypes in sub-Saharan African sheep and in the Red Maasai and Black Head Persian sheep breeds in particular. The data provide base-line information on genetic susceptibility of the two sheep breeds to scrapie, which may be useful in policy formulation for prevention and future research on prion diseases.  相似文献   

4.
《Small Ruminant Research》2009,85(1-3):41-46
Data on linear body measurements (LBM) of 403 sheep collected in three areas of KwaZulu-Natal were utilized to develop a prediction equation for live body weight of Zulu sheep. Data were collected on live weight (LW), heart girth (HG), wither height (WH) and scrotum circumference (SC) on sheep of all ages. The age of sheep was estimated by dentition. The analysis of variance showed that age and sex were important factors contributing to variation in LW of Zulu sheep. Phenotypic correlation coefficients and regression equations of LW on HG, WH and SC were computed within different age groups (milk set of teeth, one pair, two pairs and the three and four pairs of incisors). Low correlation coefficients (r = 0.21–0.48) between LW, HG and WH were found among the pregnant ewes. The relationship between LBM and LW was stronger (r = 0.66–0.86) for males than among females (r = 0.42–0.75). The cubic polynomial of HG was the best fit (R2 = 0.76) for the live weight prediction of young sheep with milk set of teeth. The combination of HG and WH produced the best fit for the two tooth and above males and non-pregnant females. The LW prediction equations for pregnant females were not reliable (R2 = 0.05–0.26). The SC was more precise (R2 = 0.61–0.80) when estimating the live weight of young males (<15–22-month-old) than of the older rams (R2 = 0.23–0.56). It was concluded that LW of Zulu sheep can be reasonably estimated using the HG and WH. A table could be constructed for the farmers to estimate the LW of their animals.  相似文献   

5.
Genetic diversity studies in domestic animals aim at evaluating genetic variation within and across breeds mainly for conservation purposes. In Sicily, dairy sheep production represents an important resource for hilly and mountain areas economy. Their milk is used for the production of traditional raw milk cheeses, sometimes protected designation of origin (PDO) cheeses. In some cases, the quality of these products is linked to a specific breed, i.e. mono-breed labelled cheeses and it is therefore important to be able to distinguish the milk of a breed from that of others, in order to guarantee both the consumer and the breed itself. In order to investigate the genetic structure and to perform an assignment test, a total of 331 individuals (Barbaresca, BAR n = 57, Comisana, COM n = 65, Pinzirita, PIN n = 75, Sarda, SAR n = 64, and Valle del Belice, VDB n = 70) were analysed using a panel of 20 microsatellite markers. A total of 259 alleles were observed with average polymorphic information content equal to 0.76, showing that the microsatellites panel used was highly informative. Estimates of observed heterozygosity ranged from 0.65 in the BAR breed to 0.75 in the COM breed. The low value of genetic differentiation among breeds (Fst = 0.049) may indicate that these breeds are little differentiated probably due to common history and breeding practices. The low Fis and Fit values indicated low level of inbreeding within and among breeds. The unrooted neighbor-joining dendrogram obtained from the Reynold's genetic distances, and factorial correspondence analysis revealed a separation between BAR and the other sheep breeds. Recent migration rates were estimated, showing that four out of the five breeds have not received a significant proportion of migrants. Only for the PIN breed a recent introgression rate from the VDB breed (7.2%) was observed. The Bayesian assignment test showed that BAR and SAR breeds had a more definite genetic structure (proportion of assignment of 92% and 86.6%, respectively), whereas the lowest assignment value was found in the PIN breed (67.1%). Our results indicated high genetic variability, low inbreeding and low genetic differentiation, except for BAR breed, and were in accordance with geographical location, history, and breeding practices. The low robustness of the assignment test makes it unfeasible for traceability purposes, due to the high level of admixture, in particular for COM, PIN and VDB.  相似文献   

6.
A novel hemoglobin variant was observed in pure sheep (Ovis aries) breeds of the island of Chios (Greece), Egypt and Hungary. This silent variant was identified by gel electrophoresis and RP-HPLC of dissociated globin chains. Two Arg for Lys substitutions were detected, by means of MALDI TOF electrospray mass spectrometric analysis for the intact globins, at positions β66(E10) and β144(HC1) of a globin chain having the sequence of the βB chain. Sequencing of the β-globin gene confirmed the variant gene as being an allele of the HBBB locus having the AAG  AGG and the AAA  AGA mutations at codons 66 and 144, respectively, both corresponding to the Lys  Arg substitution. The intrinsic oxygen affinity of the variant Hb (logP50 = 0.79 at pH 7.0) was found to be intermediate between that of the sheep Hb B (logP50 = 0.92) and that of Cypriot mouflon (O. a. ophion) Hb (logP50 = 0.53), the latter having only the Lys  Arg change at β144, whereas nearly no differences were observed in the presence of the Cl physiological effector. Result supports the indication that Arg at β144 enhances the role of the ligand in decreasing oxygen affinity, this effect being partially counteracted when Arg is at β66. Data also shows that the Lys  Arg change at β66 is responsible for 1.49 fold reduction in the intrinsic oxygen affinity. This hitherto undescribed variant increases to seven the number of alleles at the sheep HBBB locus. Following the nomenclature used for human Hb variants, the new allele was termed as the Hb Chios or [βB66(E10) Lys  Arg, 144(HC1)Lys  Arg], whereas the proposed genetic nomenclature of the locus is HBBK.  相似文献   

7.
The aim of this research was to investigate the genetic structure at BMPR 1B, BMP15 and GDF9 prolificacy genes in five sheep breeds reared in Tunisia: Barbarine, Queue Fine de L’Ouest, Noire de Thibar, Sicilo-Sarde and D’man. Genomic DNA of 204 sheep was investigated for the FecBB (BMPR 1B), FecXR, FecXH, FecXI, FecXL, FecXG, FecXB (BMP15) and FecGH (GDF9) mutations. The sequence variability of the different DNA fragments utilised for genotyping was further investigated by Single Stranded Conformation Polymorphism (SSCP) and sequencing. All the above-mentioned mutations were absent in the five sheep breeds examined. SSCP analysis and sequencing allowed the detection of two nucleotide variations. A non-functional mutation (T/C transition at nt 747 of BMP15 cDNA known as B3) was found at the BMP15 gene, in the Noire de Thibar breed; this mutation was first detected in the Belclare sheep. A new nucleotide change G/A at nt 1159 of BMP15 cDNA, causing the amino acid change A119T in the mature peptide, was detected in the Barbarine breed for the first time. The highly prolific D’man ewes were monomorphic for the absence of all the known prolificacy alleles.  相似文献   

8.
We report for the first time kinetic and thermodynamic properties of soluble acid invertase (SAI) of sugarcane (Saccharum officinarum L.) salt sensitive local cultivar CP 77-400 (CP-77). The SAI was purified to apparent homogeneity on FPLC system. The crude enzyme was about 13 fold purified and recovery of SAI was 35%. The invertase was monomeric in nature and its native molecular mass on gel filtration and subunit mass on SDS-PAGE was 28 kDa. SAI was highly acidic having an optimum pH lower than 2. The acidic limb was missing. Proton transfer (donation and receiving) during catalysis was controlled by the basic limb having a pKa of 2.4. Carboxyl groups were involved in proton transfer during catalysis. The kinetic constants for sucrose hydrolysis by SAI were determined to be: km = 55 mg ml?1, kcat = 21 s?1, kcat/km = 0.38, while the thermodynamic parameters were: ΔH* = 52.6 kJ mol?1, ΔG* = 71.2 kJ mol?1, ΔS* = ?57 J mol?1 K?1, ΔG*E–S = 10.8 kJ mol?1 and ΔG*E–T = 2.6 kJ mol?1. The kinetics and thermodynamics of irreversible thermal denaturation at various temperatures 53–63 °C were also determined. The half -life of SAI at 53 and 63 °C was 112 and 10 min, respectively. At 55 °C, surprisingly the half -life increased to twice that at 53 °C. ΔG*, ΔH* and ΔS* of irreversible thermal stability of SAI at 55 °C were 107.7 kJ mol?1, 276.04 kJ mol?1 and 513 J mol?1K?1, respectively.  相似文献   

9.
《Small Ruminant Research》2010,92(2-3):219-224
Four experiments were conducted to evaluate the effectiveness of a new controlled drug releasing device containing 0.3 g progesterone (DICO®) on ovarian control in sheep. In experiment 1, serum progesterone concentrations induced by a 14 days treatment of DICO® (n = 9) and CIDR-G® (n = 9) were compared in ovariectomized ewes. Both devices induced similar responses and no differences were recorded. In experiment 2, the onset of oestrus and the time of ovulation obtained after 14 days treatment with DICO® (n = 8) and CIDR-G® (n = 7) were compared in cyclic ewes. Both devices induced oestrus and ovulation in all of the ewes. The onset of oestrus (34.5 ± 2.8 and 30.0 ± 7.7 h), the time of ovulation (60.0 ± 9.1 and 54.9 ± 6.4 h), the ovulation rate (1.3 ± 0.5 and 1.4 ± 0.5), the follicular diameter at ovulation (7.0 ± 0.8 and 7.3 ± 1.1 mm), and the lifespan of the ovulatory follicles (8.6 ± 2.2 and 10.0 ± 2.9 days) were similar for the DICO® and CIDR-G® devices, respectively. In Experiment 3, the re-utilization of DICO® devices inserted for 6 days (i.e. short-term protocol) was evaluated in ovariectomized ewes. The females received a re-used (previously used for 6 days; n = 11) or a new DICO® (n = 11) for a period of 6 days. The re-used DICO® devices induced a lower serum progesterone concentration than the new devices (P < 0.05). However, the re-used DICO® device maintained serum progesterone concentrations above 7.1 nmol/L (i.e. >2 ng/ml) throughout treatment. In Experiment 4, the administration of eCG treatment at DICO® withdrawal was evaluated in cyclic ewes. The short-term protocol using DICO® devices for 6 days was applied with (n = 8) or without (n = 7) 300 IU eCG at the time of device withdrawal. The administration of eCG advanced ovarian follicular development, synchronizing the onset of oestrus at 36 h and the time of ovulation at 60 h from device withdrawal. In conclusion, data from these experiments show the use of DICO® or CIDR-G® devices containing 0.3 g of progesterone to have a similar efficiency in controlling serum progesterone concentrations, follicular development and the time of ovulation in sheep. The re-use of the devices, associated with the short-term protocol for 6 days is possible, although further studies on induced fertility rates are warranted.  相似文献   

10.
Twelve four-month old Suffolk × Small-tail-Han male sheep (live weight 21–26 kg), fitted with rumen and abomasum fistulas and nourished by total intragastric infusions, were used to study the relationship between the volatile fatty acids (VFA) supply and the nitrogen (N) retention in sheep. The animals were randomly divided into four groups and four levels of mixed VFA energy (the molar proportion of acetic acid, propionic acid and butyric acid was 65:25:10), i.e. 333, 378, 423 and 468 kJ kg?1 W0.75 d?1, were infused into the rumen, as treatments I, II, III and IV, respectively. The results showed that the N retention was significantly increased (P < 0.05) with the VFA infusion level. Significant regression relationship was found between the VFA supply (x, g d?1) and the N retention (y, mg d?1): y = 2.75x ? 403, r2 = 0.86, n = 12, P < 0.01. It was concluded that to get efficient utilization of dietary N and high N retention in sheep, it is necessary to supply enough dietary energy.  相似文献   

11.
Arthrospira (Spirulina) platensis (Nordstedt) Gomont was autotrophically cultivated for biomass production in repeated fed-batch process using urea as nitrogen source, with the aim of making large-scale production easier, increasing cell productivity and then reducing the production costs. It was investigated the influence of the ratio of renewed volume to total volume (R), the urea feeding time (tf) and the number of successive repeated fed-batch cycles on the maximum cell concentration (Xm), cell productivity (Px), nitrogen-to-cell conversion yield (Yx/n), maximum specific growth rate (μm) and protein content of dry biomass. The experimental results demonstrated that R = 0.80 and tf = 6 d were the best cultivation conditions, being able to simultaneously ensure, throughout the three fed-batch cycles, the highest average values of three of the five responses (Xm = 2101 ± 113 mg L?1, Px = 219 ± 13 mg L?1 d?1 and Yx/n = 10.3 ± 0.8 g g?1).  相似文献   

12.
《Cytokine》2015,74(2):283-287
Encephalitic listeriosis in sheep is a life-threatening disease. However, little is known about the cytokine response and their predictive value in this disease. The aim of present study was to assess the prognostic significance of Tumor Necrosis Factor-α (TNF-α), Interleukin-12(p40) (IL-12 p40), Interleukin-6 (IL-6), and Interleukin 10 (IL-10) levels in cerebrospinal fluid (CSF) in sheep with encephalitic listeriosis. Fifty-nine ewes in 14 flocks were diagnosed clinically as having listeriosis. CSF was collected and subjected to bacteriological examination and estimation of selected cytokines. Twenty-eight ewes were confirmed to be infected with Listeria monocytogenes. Based on antimicrobial sensitivity test, sheep were treated and the outcome was recorded as survivors (n = 10) and non-survivors (n = 18). Cutoff points for CSF cytokines were determined by Receiver operating characteristic analysis (ROC). Association between levels of CSF cytokines and outcome of listeriosis was assessed by logistic regression. TNF-α, IL-6 and IL-12(p40) levels as well as TNF-α/IL-10 ratio were significantly higher in non-survivors than survivors (p = 0.002, 0.0021, 0.0033, and 0.001, respectively). However, IL-10 level was significantly lower in non-survivors than survivors (p = 0.0058). ROC analysis revealed that IL-6 and TNF-α/IL-10 ratio had the highest AUC values (0.98, 0.984, respectively). Final multivariate logistic regression model showed that TNF-α/IL-10 ratio was the only variable that has predictive value for mortality in diseased sheep (p: 0.001; OR: 7.2; 95% CI: 5.7–9.8). TNF-α showed a positive correlation with IL-12β (r = 0.917) and IL-6 (r = 0.965). IL-12 (p40) showed also a positive correlation with IL-6 (r = 0.906). However, IL-10 showed a negative correlation with TNF-α (r = −0.915), IL-12(p40) (r = −0.790), and IL-6 (r = −0.902). In conclusion, TNF-α/IL-10 ratio may provide predictive information about outcome of encephalitic listeriosis in sheep.  相似文献   

13.
《Inorganica chimica acta》2006,359(11):3549-3556
A series of cationic trispyrazolylmethane complexes of the general form [TmRM(CH3CN)3]2+ (Tm = tris(pyrazolyl)methane, 1, R = 3,5-Me2, M = Fe(II); 2, R = 3-Ph, M = Fe(II); 3, R = 3,5-Me2, M = Co(II); 4, R = 3-Ph, M = Co(II)) with ‘piano-stool’ structures was prepared by the reaction of the N3tripodal ligands (TmR)with [(CH3CN)6M](BF4)2 in a 1:1 stoichiometric ratio. Magnetic susceptibility measurements indicate that all four complexes with BF4 counter anions are paramagnetic, high-spin systems in the solid state with μeff at high temperatures of 5.2 (1, S = 2), 5.4 (2, S = 2), 4.9 (3, S = 3/2) and 4.6 (4, S = 3/2) BM, respectively. Comparisons of bond lengths from the metal centre to the TmR nitrogen donors, and from the metal centre to the acetonitrile nitrogen donors indicate that the neutral tripodal ligands appear to be more weakly coordinated to the metal centre than are the acetonitrile ligands. Reactions of these tripodal complexes with bidentate phosphine ligands, such as 1,2-diphosphinoethane or 1,2-bis(diallylphosphino)ethane leads to displacement of the tripodal ligand, or to the formation of more thermally stable bis-ligand complexes M(TmR)2 (R = 3,5-dimethyl).  相似文献   

14.
《Small Ruminant Research》2000,35(3):249-253
Electrophoretic separation of creatine kinase (ATP: creatine phosphotransferase, E.C. 2.7.3.2) isoenzymes in agarose gel was made in the serum of 93 sheep of three Slovenian domestic breeds (Solcavska, Pramenka and Bovska breeds). 44 sheep were pregnant between 112 and 135 days at the time of the blood collection. The median value of serum total CK activity for all animals investigated was 82 U/l. After direct immunoinhibition of CK with anti-M-CK monoclonal antibodies the total CK activity remained the same (88 U/l, P = 0.354). There were significant differences among breeds in CK activity for the Solcavska (101 U/l), Bovska (89 U/l) and Pramenka breeds (73 U/l), respectively (Kruskal–Wallis one way analysis of variance, P < 0.01), and between pregnant (105 U/l) and non-pregnant animals (76 U/l), irrespective of the breed (Mann–Whitney rank sum test, P < 0.05). According to electrophoresis, all non-pregnant sheep had exclusively free CK-BB serum bands activity. In all pregnant sheep coupled dimeric BB variant appeared as macro-CK type 1 in the range between 80% and 100% of total CK activity. The present study confirms the existence of an elimination mechanism for CK from the plasma abundance free CK-BB enzyme.  相似文献   

15.
We report the effects of ATP and Mg2+ on the activity of intracellular chloride channels. Mitochondrial and lysosomal membrane vesicles isolated from rat hearts were incorporated into bilayer lipid membranes, and single chloride channel currents were measured. The observed chloride channels (n = 112) possessed a wide variation in single channel parameters and sensitivities to ATP. ATP (0.5–2 mmol/l) modulated and/or inhibited the chloride channel activities (n = 38/112) in a concentration-dependent manner. The inhibition effect was irreversible (n = 5/93) or reversible (n = 15/93). The non-hydrolysable ATP analogue AMP-PNP had a similar inhibition effect as ATP, indicating that phosphorylation did not play a role in the ATP inhibition effect. ATP modulated the gating properties of the channels (n = 6/93), decreased the channels' open dwell times and increased the gating transition rates. ATP (0.5–2 mmol/l) without the presence of Mg2+ decreased the chloride channel current (n = 12/14), whereas Mg2+ significantly reversed the effect (n = 4/4). We suggest that ATP-intracellular chloride channel interactions and Mg2+ modulation of these interactions may regulate different physiological and pathological processes.  相似文献   

16.
Structural polymorphism is one of the important issues with regard to G-quadruplexes because the structural diversity may significantly affect their biological functions in vivo and their physical property in nano-material. A series of oligonucleotides with four repeat guanines sequence [d(G4Tn)3G4 (n = 1–6)] were designed. In this study, the effects of loop length on the formation of structures of G-quadruplex were investigated through the result of CD (circular dichroism) and 20% non-denatured polyacrylamide gel electrophoresis. Our studies demonstrate that the length of loop in 100 mM KCl solution could predict the conformation of G-quadruplex.  相似文献   

17.
The polymorphism of mutation Q249R in BMPR-IB gene (FecB) and loci FecXI, FecXH, FecXG, FecXB in BMP15 gene was analyzed by forced PCR-RFLP method in 550 individuals from 6 flocks or breeds of goats with litter size varied from 1.4 to 2.7 including Boer (209), Haimen (128), second generation of Boer goat crossed with Huanghuai goat (82), Huanghuai (71), Nubi (37) and Matou (23) goat. None of mutations was detected in these goat breeds and their crossbreed. These results suggest that fecundity of goat is not linked to the same loci in BMPR-IB and BMP15 as sheep. Therefore, it is necessary to seek for other genes or loci in order to develop marker assistance selection techniques and study the prolific mechanism of the goat.  相似文献   

18.
The neuronal ceroid lipofuscinoses (NCLs, Batten disease) are a group of fatal recessively inherited neurodegenerative diseases of humans and animals characterised by common clinical signs and pathology. These include blindness, ataxia, dementia, behavioural changes, seizures, brain and retinal atrophy and accumulation of fluorescent lysosome derived organelles in most cells. A number of different variants have been suggested and seven different causative genes identified in humans (CLN1, CLN2, CLN3, CLN5, CLN6, CLN8 and CTSD). Animal models have played a central role in the investigation of this group of diseases and are extremely valuable for developing a better understanding of the disease mechanisms and possible therapeutic approaches. Ovine models include flocks of affected New Zealand South Hampshires and Borderdales and Australian Merinos. The ovine CLN6 gene has been sequenced in a representative selection of these sheep. These investigations unveiled the mutation responsible for the disease in Merino sheep (c.184C > T; p.Arg62Cys) and three common ovine allelic variants (c.56A > G, c.822G > A and c.933_934insCT). Linkage analysis established that CLN6 is the gene most likely to cause NCL in affected South Hampshire sheep, which do not have the c.184C > T mutation but show reduced expression of CLN6 mRNA in a range of tissues as determined by real-time PCR. Lack of linkage precludes CLN6 as a candidate for NCL in Borderdale sheep.  相似文献   

19.
Nosema ceranae and Nosema apis are microsporidia which play an important role in the epidemiology of honeybee microsporidiosis worldwide. Nosemiasis reduces honeybee population size and causes significant losses in honey production. To the best of our knowledge, limited information is available about the prevalence of nosemiasis in Italy. In this research, we determined the occurrence of Nosema infection in Central Italy. Thirty-eight seemingly healthy apiaries (2 to 4 hives each) were randomly selected and screened from April to September 2014 (n = 11) or from May to September 2015 (n = 27). The apiaries were located in six areas of Central Italy, including Lucca (n = 11), Massa Carrara (n = 9), Pisa (n = 9), Leghorn (n = 7), Florence (n = 1), and Prato (n = 1) provinces. Light microscopy was carried out according to current OIE recommendations to screen the presence of microsporidiosis in adult worker honeybees. Since the morphological characteristics of N. ceranae and N. apis spores are similar and can hardly be distinguished by optical microscopy, all samples were also screened by multiplex polymerase chain reaction (M-PCR) assay based on 16S rRNA-gene-targeted species-specific primers to differentiate N. ceranae from N. apis. Furthermore, PCR-positive samples were also sequenced to confirm the species of amplified Nosema DNA. Notably, Nosema spores were detected in samples from 24 out of 38 (63.2%, 95% CI: 47.8–78.5%) apiaries. Positivity rates in single provinces were 10/11, 8/9, 3/9, 1/7, or 1/1 (n = 2). A full agreement (Cohen's Kappa = 1) was assessed between microscopy and M-PCR. Based on M-PCR and DNA sequencing results, only N. ceranae was found. Overall, our results highlighted that N. ceranae infection occurs frequently in the cohort of honeybee populations that was examined despite the lack of clinical signs. These findings suggest that colony disease outbreaks might result from environmental factors that lead to higher susceptibility of honeybees to this microsporidian.  相似文献   

20.
《Small Ruminant Research》2009,82(2-3):171-173
The objective was to evaluate long-acting moxidectin (Cydectin® 2% LA for sheep) against trichostrongylids in sheep. We performed a blocked, parallel, controlled clinical trial. We included 45 ewe-lambs, allocated into treated (n = 30, 1.0 mg moxidectin per kg bw, subcutaneously at base of ear on D 0) or controls (n = 15). Animals had been naturally infected (pre-treatment geometric mean epg counts: 233 and 249, respectively) and throughout the study grazed at the same pasture. Fortnightly, we collected faecal samples and performed established parasitological techniques (epg counts, coprocultures). We used analysis of covariance for post-treatment results, using pre-treatment counts as covariate, treatment as fixed effect, block as random effect. Geometric mean epg counts in treated animals were 0 up to D 112, 1 on D 126, 4 on D 140 and 13 on D 161. Respective figures for controls were 369–820 up to D 140 and 168 on D 161 (p < 0.05). Persistent efficacy (>90%) was 140 d for Teladorsagia, 119 d for Haemonchus and 115 d for Trichostrongylus. This is the first reported clinical trial of efficacy of long-acting moxidectin in sheep in Europe. Cydectin 2% LA was found to be effective against trichostrongylids of sheep. The particularly long persistent efficacy can provide new possibilities in formulating anthelmintic programs for sheep.  相似文献   

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