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1.
The fungus Clonostachys rosea f. rosea has the potential to control gastrointestinal nematodes (GIN) of sheep. A study was conducted using adult Merino sheep. Gender, egg count and initial body weights (BWs) were used to categorise animals into four groups which were randomly assigned to one of four C. rosea dietary treatments. Treatments were mixed with a complete diet and fed to sheep once daily for 10 weeks. There was no effect of treatment on eggs per gram of faeces. However, treatments reduced the number of larvae per gram in faecal cultures (P < 0.001) and larval development (LD) time (P < 0.001). Efficacy of treatments increased (P < 0.001) with time. On Day 70, treatments of 0.25, 0.5 and 1.0 g of C. rosea chlamydospores per kilogram BW reduced LD time by 33, 72 and 89%, respectively, whereas in the control, LD was reduced by only 2.6%. C. rosea significantly (P < 0.001) reduced numbers of third-stage larvae (L3) found in pastures. Our findings suggest that daily feeding with C. rosea has a potential to reduce larval stages of GIN in pastures.  相似文献   

2.
An experiment was conducted at Ukulinga Research Farm using 24 Merino sheep to test a combination of plant Ananas comosus (Ac) and fungus Clonostachys rosea (Cr) in controlling nematode parasites. Four treatments were assigned: 100 mg kg?1 body weight (BW) ethanol extract of Ac, 1 g of Cr product kg?1 BW, the combination of both treatments (AcCr), and a Control. Sheep within a treatment were paired and penned in individual paddocks, and rectal faecal samples were taken for counting of eggs per gram (EPG) of faeces and third-stage (L3) larvae. Grass samples were taken every 21 days for counting of L3 larvae. A. comosus and AcCr reduced (P < 0.001) EPG. A. comosus, C.rosea and AcCr reduced (P < 0.001) L3 counts. The efficacy of treatments increased with time (P < 0.001). C. rosea and AcCr reduced (P < 0.001) L3 on grass. In conclusion, AcCr is better at controlling nematodes than either Ac or Cr individually.  相似文献   

3.
A total of 190 rabbit females were used to evaluate five feeding programmes from 9 weeks of age to the first parturition: CAL, fed ad libitum with a control diet (C: 11.0 MJ digestible energy (DE) and 114 g digestible protein (DP)/kg dry matter (DM)) until first parturition; CR, fed ad libitum with C diet until 12 weeks of age and then C diet restricted (140 g/day) until first parturition; F, fed ad libitum with a low-energy, high-fibre diet (F: 8.7 MJ DE and 88 g DP/kg DM) until first parturition; FC, fed with F diet ad libitum until 16 weeks of age, and C diet ad libitum until first parturition; FCF, fed with F diet ad libitum until 16 weeks of age, then C diet ad libitum until 20 weeks and then F diet ad libitum until first parturition. The rabbits were artificially inseminated at 18 weeks of age. CAL group had a higher mortality rate compared with the other groups between 9 and 12 weeks of age (34% v. 3%; P < 0.05) and during the last 3 weeks of first pregnancy (14% v. 3%; P < 0.05). The CAL and FC females presented higher BW and perirenal fat thickness (PFT) than CR females at 11 days of pregnancy (+0.41 kg and +0.6 mm; P < 0.05), with F females showing medium values. The type of feeding procedure did not affect the fertility rate of young females at first artificial insemination. Differences in BW disappeared at parturition, when only CAL females presented a greater PFT than CR and FC females (+0.3 mm; P < 0.05). In comparison with FCF, CAL females had smaller and thinner live born litters (−2.5 kits and −139 g, respectively; P < 0.05), with CR, F and FC females showing medium values. The low number of kits born alive for CAL females was because of their lesser total number of kits born (−1.7 kits; P < 0.05) and the greater mortality of their litters at birth (+13.9%; P < 0.05) compared with FCF females. Non-esterified fatty acid was higher in the blood of females fed C diet (CAL and CR) than in others at partum day (on average +0.15 mmol/l; P < 0.05). In conclusion, the ad libitum use of diets for lactating rabbit does throughout the rearing period could lead young rabbit females to present a higher risk of early death and smaller litter size at first parturition. Feed restriction or earlier use of suitably fibrous diets led females to achieve the critical BW and fat mass at first mating to ensure reproduction.  相似文献   

4.
Clonostachys rosea is a promising saprophytic filamentous fungus that belongs to phylum Ascomycota. Clonostachys rosea is widespread around the world and exists in many kinds of habitats, with the highest frequency in soil. As an excellent mycoparasite, C. rosea exhibits strong biological control ability against numerous fungal plant pathogens, nematodes and insects. These behaviours are based on the activation of multiple mechanisms such as secreted cell-wall-degrading enzymes, production of antifungal secondary metabolites and induction of plant defence systems. Besides having significant biocontrol activity, C. rosea also functions in the biodegradation of plastic waste, biotransformation of bioactive compounds, as a bioenergy sources and in fermentation. This mini review summarizes information about the biology and various applications of C. rosea and expands on its possible uses.  相似文献   

5.
Population dynamics ofDaphnia rosea in a small eutrophic pond   总被引:2,自引:0,他引:2  
The population dynamics ofDaphnia rosea were studied in a small, eutrophic fish-free pond during November 1986–November 1987.D. rosea showed two density peaks in 1987, a high peak in spring and a slightly lower one in autumn, but they disappeared in mid- and late summer when a smaller cladoceran,Ceriodaphnia reticulata, dominated. The rapid decline in density ofD. rosea in mid-May and the low density in June/July were preceded by or coincided with a period of increased male density, the appearance of ephippial females, smaller body length of adult females, decreased brood size, and increased frequency of empty brood chambers, all of which indicate a worsening food situation. The rapid density decline ofD. rosea in mid-May was considered attributable neither to increasing water temperature, nor predation by the dipteranChaoborus flavicans, but to insufficient food conditions for the maintenance of stable reproduction. Although edible phytoplankton was abundant in June/July, the general food situation was not suitable forD. rosea due to blooms of the large-celled dinoflagellate,Ceratium hirundinella, which probably inhibited the feeding activity ofD. rosea. TheC. hirundinella blooms might also be important for the shift of the dominant herbivore from the largerD. rosea to the smallerCeriodaphnia reticulata in August/September.  相似文献   

6.
In our current study, four nickel-tolerant (Ni-tolerant) bacterial species viz, Bacillus thuringiensis 002, Bacillus fortis 162, Bacillus subtilis 174, and Bacillus farraginis 354, were screened using Ni-contaminated media. The screened microbes exhibited positive results for synthesis of indole acetic acid (IAA), siderophore production, and phosphate solubilization. The effects of these screened microbes on Ni mobility in the soil, root elongation, plant biomass, and Ni uptake in Althea rosea plants grown in Ni-contaminated soil (200 mg Ni kg?1) were evaluated. Significantly higher value for water-extractable Ni (38 mg kg?1) was observed in case of Ni-amended soils inoculated with B. subtilis 174. Similarly, B. thuringiensis 002, B. fortis 162, and B. subtilis 174 significantly enhanced growth and Ni uptake in A. rosea. The Ni uptake in the shoots and roots of B. subtilis 174-inoculated plants enhanced up to 1.7 and 1.6-fold, respectively, as compared to that in the un-inoculated control. Bacterial inoculation also significantly improved the root and shoot biomass of treated plants. The current study presents a novel approach for bacteria-assisted phytoremediation of Ni-contaminated areas.  相似文献   

7.
To better understand the effects of reduced feeding frequency on the GH–IGF-I axis, channel catfish (Ictalurus punctatus), were either fed (Fed control, commercial diet fed daily), fed every other day (FEOD, commercial diet fed every other day), or not fed (Unfed, no feed). Pituitary GH mRNA increased whereas hepatic growth hormone receptor (GHR), IGF-I mRNA, and plasma IGF-I decreased in the FEOD and Unfed fish (P < 0.05). In another study, fish were either continually fed (Fed) or fasted and then re-fed (Restricted) to examine the physiological regulation of somatostatin-14 (SS-14) and SS-22 mRNA. Fasting increased (P < 0.05) levels of SS-14 mRNA in the hypothalamus and pancreatic islets (Brockmann bodies) at d 30 while re-feeding decreased SS-14 mRNA to control values in all tissues examined by d 45. Fasting had no effect on levels of SS-22 mRNA in the pancreatic islets whereas SS-22 mRNA was not detected in the stomach or hypothalamus. The results demonstrate that feeding every other day has similar negative impacts on components of the GH–IGF-I axis as fasting. The observed increase in SS-14 mRNA in the hypothalamus and pancreatic islets suggests a role for SS-14 in modulating the GH–IGF-I axis in channel catfish.  相似文献   

8.
The present 20‐day trial was performed in order to improve growth of tench Tinca tinca (L.) larvae reared intensively in a controlled environment. Larvae of 4.53 mm initial length, 45 per dm3, were fed each day with live Artemia nauplii for 12, 18 or 24 h at 28°C. Final survival rates were very high in all treatment groups, ranging from 88.9 to 91.8%. Duration of daily feeding significantly affected growth and final condition, expressed by Fulton's coefficient (K) (P ≤ 0.05, Duncan's test). The fastest larval growth (17.6 mm total length, TL; 88.8 mg body weight, BW) and the best condition (K = 1.54) were recorded in the group fed 24 h each day. The second best results were attained with the larvae fed 18 h a day (16.5 mm TL, 67.9 mg BW, K = 1.40) whereas those fed 12 h daily grew the slowest (13.5 mm TL, 31.7 mg BW) and showed the worst condition (K = 1.19). Thus, to maximize growth and condition of tench larvae being reared at the optimal growth temperature, intensive 24 h feeding is necessary.  相似文献   

9.
Whitefly (Bemisia tabaci) is a notorious insect pest of many economic important crop plants including cotton, tomato, etc. The main objective of the study was to evaluate the efficacy of new biological control agent to replace toxic chemical pesticides from agro-ecosystem. Clonostachys rosea associated with whitefly and aphid (Aphis gossypii) on cotton plants was isolated and characterised on a morphological and molecular basis. Phylogenetic analysis was also performed based on the internal transcribed spacer (ITS) region. Pathogenicity of C. rosea was evaluated in two concentrations against fourth instar nymphal and adult stages of B. tabaci. The study revealed that C. rosea was highly parasitic against fourth instar nymphs than adults at different spore concentrations. Two isolates of C. rosea were identified in this study, and both were morphologically similar. However, differences were observed in the ITS region of the C. rosea isolates. Our results showed that C. rosea has the prospects to serve as a potential biocontrol agent against economically important insect pests.  相似文献   

10.
The fungal diversity structures of soils that are suppressive and non-suppressive to Sclerotinia sclerotiorum were characterised and screened for fungal strains antagonistic to the S. sclerotiorum pathogen. Soil suppressiveness was associated with a particular fungal diversity structure. Principal component analysis showed that antagonism by fungal species in suppressive soils was associated with the occurrence of Fusarium oxysporum, Fusarium solani, Talaromyces flavus var. flavus and Clonostachys rosea f. rosea. In particular, C. rosea f. rosea occurred exclusively in suppressive soil samples, suggesting that this morpho-species plays an important role in suppression of S. sclerotiorum diseases. One strain of C. rosea f. rosea (BAFC1646) was selected for further experiments. Dual-culture assays confirmed the antagonistic behaviour of C. rosea f. rosea BAFC1646 against three different S. sclerotiorum strains. Antifungal activity was corroborated by diffusion assays with metabolite extracts. Greenhouse assays with soybean plants showed that the selected C. rosea f. rosea strain reduced the percentage of dead plants when co-inoculated with S. sclerotiorum. In addition, inclusion of C. rosea f. rosea alone increased shoot lengths significantly. In this work, we established the involvement of fungal species in soil suppressiveness and in further assays confirmed that C. rosea f. rosea BAFC1646 exhibits a bioprotective effect against S. sclerotiorum in soybean plants.  相似文献   

11.
This study assessed the long-term effects of feeding diets containing either a gelling fibre (alginate (ALG)), or a fermentable fibre (resistant starch (RS)), or both, on feeding patterns, behaviour and growth performance of growing pigs fed ad libitum for 12 weeks. The experiment was set up as a 2×2 factorial arrangement: inclusion of ALG (yes or no) and inclusion of RS (yes or no) in the control diet, resulting in four dietary treatments, that is, ALG−RS− (control), ALG+RS−, ALG−RS+, and ALG+RS+. Both ALG and RS were exchanged for pregelatinized potato starch. A total of 240 pigs in 40 pens were used. From all visits to an electronic feeding station, feed intake and detailed feeding patterns were calculated. Apparent total tract digestibility of energy, dry matter (DM), and CP was determined in week 6. Pigs’ postures and behaviours were scored from live observations in weeks 7 and 12. Dietary treatments did not affect final BW and average daily gain (ADG). ALG reduced energy and DM digestibility (P<0.01). Moreover, ALG increased average daily DM intake, and reduced backfat thickness and carcass gain : digestible energy (DE) intake (P<0.05). RS increased feed intake per meal, meal duration (P<0.05) and inter-meal intervals (P=0.05), and reduced the number of meals per day (P<0.01), but did not affect daily DM intake. Moreover, RS reduced energy, DM and CP digestibility (P<0.01). Average daily DE intake was reduced (P<0.05), and gain : DE intake tended to be increased (P=0.07), whereas carcass gain : DE intake was not affected by RS. In week 12, ALG+RS− increased standing and walking, aggressive, feeder-directed, and drinking behaviours compared with ALG+RS+ (ALG×RS interaction, P<0.05), with ALG−RS− and ALG−RS+ in between. No other ALG×RS interactions were found. In conclusion, pigs fed ALG compensated for the reduced dietary DE content by increasing their feed intake, achieving similar DE intake and ADG as control pigs. Backfat thickness and carcass efficiency were reduced in pigs fed ALG, which also showed increased physical activity. Pigs fed RS changed feeding patterns, but did not increase their feed intake. Despite a lower DE intake, pigs fed RS achieved similar ADG as control pigs by increasing efficiency in DE use. This indicates that the energy utilization of RS in pigs with ad libitum access to feed is close to that of enzymatically digestible starch.  相似文献   

12.
Low temperatures increase mortality of calves but we know little of calves’ abilities to thermoregulate. To examine effects of milk feeding level on thermoregulatory behaviour, 27 Holstein calves were housed for 3 d after birth in individual pens fitted with heat lamps at one end to provide a thermal gradient. They were fed milk at a high (30% BW) or low (8% BW) daily allowance. Daily temperatures in the barn were 6.27 ± 3.12 °C, range: −5.46 °C to 16.63 °C. Temperature loggers were fitted to each calf to record ambient temperatures chosen by the calf. Video cameras recorded the calf's distance from the heat lamp and lying posture (on sternum or side, with legs extended or contracted) for 24 h/d, and records were scored every 20 min. Calves spent most time in the portion of the pen with heat lamps (Proc Mixed P < 0.05) but there was no effect of feeding level (P > 0.10). Calves tended to be closer to the heat lamp during the coldest periods of the day than during the warmer periods (P < 0.10). The difference between the temperature recorded in the barn and the temperature recorded on the calf's back was correlated with distance from the heat lamp (r = 0.32, P = 0.01) showing that the temperature logger on the calf reflected the ambient temperature chosen. Time spent in different lying postures was not affected by feeding level or barn temperature (P > 0.10). Young calves show a preference for warmer environments but this preference does not interact with the amount of milk fed. Temperature recorders attached to the calves can measure calves’ thermal preferences. Calves did not thermoregulate through changes in resting posture.  相似文献   

13.
Summary Allolobophora rosea (Savigny) was found to be common in mull type soils beneath bramble (Rubus fruticosus L.). Burrow construction in this soil type in the laboratory at 4.4, 10.0 and 14.8°C ranged between 133 and 516 mm g-1 fresh wt of worm day-1. Burrowing was affected by both body size and temperature. Rates of soil displacement during burrowing were estimated from burrowing rates, burrow dimensions and soil density; depending on body size and temperature they were in the range 809–1,928 mg dry wt of soil g-1 fresh wt of worm day-1. These values were in reasonable agreement with measured egestion rates (range: 1,000–2,000 mg dry wt of egesta g-1 fresh wt of worm day-1). It was concluded that A. rosea eats its way through the soil and is adapted to its rapid turnover. Gut turnover times were calculated to be between 1 and 2.5 h.Direct observation indicated that feeding was by a grazing procedure and it was shown that A. rosea preferentially selects the more organic fractions of the soil for ingestion.The evaluation of energy budgets for individual small immature, large immature and adult worms at 10°C revealed respiration to production ratios (R/P) of 1.0, 1.8 and 4.1, respectively. Assimilation efficiencies (A/C) were always less than 2.5%.  相似文献   

14.
《Biological Control》2002,23(1):64-70
The results reported in this paper represent work from two separate experiments, namely a plot trial using cattle feces conducted at Kungsãngen in Uppsala, Sweden and a plot trial using sheep feces undertaken at Tåstrup in Copenhagen, Denmark. In both trials, a technique was used to monitor the level of Duddingtonia flagrans propagules in soil surrounding feces. The feces were from animals fed or not fed D. flagrans fungal chlamydospores. Also presented are the numbers of soil nematodes in soil surrounding sheep feces. The results indicate that D. flagrans has little growth beyond the fecal environment into surrounding soil when chlamydospores are fed to either sheep or cattle. This is substantiated by the soil nematode data. No statistical differences in the number of nematode taxa identified, Shannon Weiner H′, proportion of various feeding groups, and B/B + F (B and F are the proportions of bacterial and fungal-feeding nematodes) were found when soil surrounding sheep feces containing chlamydospores and parasitic nematode eggs was compared to soil surrounding feces containing parasitic nematode eggs alone. It is unlikely that the application of D. flagrans as a biological control agent against the free-living stages of nematode parasites of these livestock will negatively affect populations of nontarget soil nematodes.  相似文献   

15.
A total of 200 (Large White × Landrace) sows were used in a 39-day study to evaluate the effects of feeding a non-starch polysaccharide (NSP)-hydrolysing enzyme multicomplex (Rovabio® Excel) in conjunction with a high- or reduced nutrient-density diet during lactation on sow body condition, feed intake and progeny performance. Eight sows were selected each week for 25 weeks, blocked by parity and BW into groups of four, and within the block randomly assigned to one of the four treatments (n = 50/treatment). Treatments were: (1) LND: low energy (13.14 MJ of DE/kg), low CP (15%) diet; (2) LND + RE: LND with 50 mg/kg NSP-hydrolysing enzyme; (3) HND: high energy (14.5 MJ of DE/kg), high CP (16.5%) diet; and (4) HND + RE: HND with 50 mg/kg NSP-hydrolysing enzyme. Sows were fed treatment diets from day 109 of gestation until the day of subsequent service. Between weaning and re-service, Rovabio® Excel addition to LND diets resulted in an increase in energy intake; however, a reduction was observed when supplemented to the HND diet (P < 0.05). The inclusion of Rovabio® Excel increased feed and energy intake during week 3 (days 15 to 21) of lactation (P < 0.05). Sows fed diets supplemented with Rovabio® Excel had greater back-fat depth at weaning and service (P < 0.05); however, the magnitude of change in back-fat depth during lactation and from farrowing to service was not different between treatments. Feeding the HND diet increased energy intake before farrowing, throughout lactation and during the weaning to service interval (P < 0.01); however, overall, average daily feed intake tended to be reduced (P < 0.10). At service, sows fed the HND diet were heavier than sows fed the LND diet (P < 0.05); however, the magnitude of change in BW between treatments was not different. Feeding the HND diet to sows resulted in a tendency for heavier piglets at birth (P = 0.10) that tended to grow at a faster rate and be heavier at weaning than piglets from sows fed the LND diet (P = 0.06). These results indicate that NSP-degrading enzymes offer minimal benefit to sows and their progeny when fed before and during lactation; however, increasing energy intake of sows during lactation may beneficially affect progeny.  相似文献   

16.
Multiparous Angus×Simmental cows (n=54, 5.22±2.51 years) with male progeny were fed one of two diets supplemented with either dried distillers grains with solubles (DDGS) or soybean meal (CON), from calving until day 129 postpartum (PP) to determine effects of excess protein and fat on cow performance, milk composition and calf growth. Diets were formulated to be isocaloric and consisted of rye hay and DDGS (19.4% CP; 8.76% fat), or corn silage, rye hay and soybean meal (11.7% CP; 2.06% fat). Cow–calf pairs were allotted by cow and calf age, BW and breed. Cow BW and body condition score (BCS; P⩾0.13) were similar throughout the experiment. A weigh-suckle-weigh was performed on day 64 and day 110±10 PP to determine milk production. Milk was collected on day 68 and day 116±10 PP for analysis of milk components. Milk production was unaffected (P⩾0.75) by dietary treatments. Milk urea nitrogen was increased at both time points in DDGS compared with CON cows (P<0.01). Protein was decreased (P=0.01) and fat was increased (P=0.01) in milk from DDGS compared with CON cows on day 68 PP. Compared to CON, DDGS decreased medium chain FA (P<0.01) and increased long chain FA (P<0.01) at both time points. Saturated FA content of milk was decreased (P<0.01) at both time-points in DDGS compared with CON cows, which resulted in an increase (P<0.01) in monounsaturated and polyunsaturated FA, including cis-9, trans-11 conjugated linoleic acid. Daily gain of the DDGS calves was increased (P=0.01) compared with CON calves, resulting in heavier BW on day 129 (P=0.01). Heavier BW of DDGS calves was maintained through weaning (P=0.01). Timed-artificial insemination (TAI) rates were greater for cows fed DDGS compared with cows fed CON (P<0.02), but dietary treatment had no effect on overall pregnancy rates (P=0.64). In summary, feeding DDGS to lactating beef cows did not change cow BW or BCS, but did improve TAI rates and altered milk composition compared with CON. As a result, male progeny from cows fed DDGS during lactation had greater average daily gain and were heavier at day 129 and at weaning compared with male progeny from cows fed a control diet.  相似文献   

17.
Clonostachys rosea, a biological control agent for plant diseases, is found in a variety of habitats and colonises and survives in different tissues. This antagonist is effective at controlling grey mould, which is caused by Botrytis cinerea, in different plant species. Despite the existing knowledge regarding the efficiency of C. rosea at biologically controlling grey mould, there are few studies concerning this interaction at the histological level. Therefore, we studied the antagonist–pathogen interactions using confocal microscopy. C. rosea survived in tomato tissues for at least 30 days between 18–30ºC. The antagonist colonised the wounded tomato stems faster and more efficiently than the pathogen. The colonisation of the leaf tissues by C. rosea was slow, and the spore concentration was poor in this experiment. Combined with the pathogen’s direct penetration into the leaves, this slow colonisation could cause the biological control to fail. C. rosea also preyed parasitically upon the pathogen’s hyphae, penetrated the tomato’s leaf tissue through the stomata and colonised the stem’s intercellular spaces. Root colonisation was abundant, with a dense hyphae network forming between epidermal cell junctions. This observation provided evidence that the fungus can penetrate via the roots. This paper will help to better define an application strategy for C. rosea in tomato propagation, with the goal of biological control or growth promotion, because to understand how the antagonist survives and interacts in its habitat will define how and when to apply it.  相似文献   

18.
Alnus glutinosa is an important pioneer species that forms effective symbioses with Frankia and ecto and arbuscular mycorrhizal fungi (AMF). There is evidence that Frankia and AMF interact and the focus of this study was to investigate how interactions affected root system and root hair development. A. glutinosa seedlings were grown in pots in soil pre-inoculated with the AMF Gigaspora rosea. Seedlings were inoculated with Frankia either immediately on transfer to AMF-inoculated pots (day 0) on day 15 or on day 30 following AMF inoculation so the effect of timing of inoculation on interactions could be determined. Seedlings were harvested in batches at intervals of 10, 15, 20, 25 and 30 days after the commencement of each treatment. Both G. rosea and Frankia increased root branching and effects were greater when both were present. By contrast, both G. rosea and Frankia decreased root hair numbers markedly. Effects on root hair development were not a consequence of phosphorous, as P levels were not changed significantly in seedlings colonised by G. rosea or nodulated by Frankia. Effects are not due to differences in root system size but conceivably could offset some of the carbon costs incurred by the symbioses.  相似文献   

19.
Rhizoctonia solani AG-3 forms sclerotia on potato tubers, reducing quality and marketability. Potato discs with sclerotia were exposed to saturated soil, and following toothpick baiting, hyphae of R. solani parasitised with mycelia that either coiled around or penetrated cell walls were observed. Similar parasitic behaviour was observed in dual cultures. Clonostachys rosea was identified as the mycoparasite by morphology and ITS sequencing. When co-inoculated onto stems grown from disease-free seed potatoes, tubers of the C. rosea?+?R. solani inoculated plants had significantly lower black scurf (P?0.0001) and higher yield (P?=?0.0002) than R. solani inoculated controls.  相似文献   

20.
K.Z. Cai  J.L. Bai   《Small Ruminant Research》2009,85(2-3):111-115
By using faecal egg counting, larvae culturing, coccidian oocysts identifying, the present study was conducted to determine infection intensity of nematodosis and coccidosis of young sheep (6–12 months) raised under three types of feeding and management regims namely, confinement system (2 farms, n = 30), semiconfinement system (2 farms, n = 30) and grazing system (2 farms, n = 30) in Ningxia Hui Autonomous Region (NHAR) in China. The mean egg counts of gastrointestinal nematodes were zero in confinement system, 63 EPG in semiconfinement system and 263 EPG in grazing system, while the mean coccidian oocyst counts (oocysts per gram of faeces, OPG) of each regim were 3784, 1713 and 687, respectively. Gastrointestinal parasite loads of sheep were attributed to low EPG (zero EPG) in confinement, moderate EPG in semiconfinement and high EPG in grazing regim, respectively, which in turn resulted in high OPG in confinement, moderate OPG in semiconfinement and low OPG in grazing regim, respectively. The infection rate of nematodes of sheep was zero in confinement, 43.33% in semiconfinement and 96.67% in grazing regim, while the infection rate of coccidia was 100%, 96.67% and 86.67%, respectively. The nematodes of sheep in grazing regim were, in the order of prevalence: Ostertagia (Teladorsagia) (80.00%), Marshallagia (66.67%), Nematodirus (63.33%), Trichostrongylus (43.33%), Haemonchus contortus (43.33%), and Chabertia (16.67%), while in semiconfinement regim were, in the same order of prevalence: 43.33%, 10.00%, 40.00%, 20%, 20% and 0%, respectively. Seven species of Eimeria were recognized in the three management regims. Their prevalence rates were E. parva (85.56%), E. ahsata (70.00%), E. ovinoidalis (34.44%), E. intricata (21.11%), E. crandallis (20.00%), E. granulosa (18.89%), and E. faurei (5.56%). These results may provide a further understanding of the factors associated with parasite epizootiology under different feeding and management regims.  相似文献   

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