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1.
Lizards have been reported as important pollinators on several oceanic islands. Here we evaluate the potential role of Galápagos lava lizards (Microlophus spp.) as pollinators across their radiation. Over 3 years, we sampled pollen transport by 9 lava lizard species on the 10 islands where they are present, including 7 single‐island endemics. Overall, only 25 of 296 individuals sampled (8.4%) transported pollen of 10 plant species, the most common being Prosopis juliflora, Exodeconus miersii, Sesuvium sp. and Cordia leucophlyctis. At least 8 of these plant species were native, and none were confirmed as introduced to the archipelago. Despite the low overall proportion of individuals carrying pollen, this was observed in 7 of the nine lizard species, and on 8 of the ten main islands (Española, Fernandina, Floreana, Isabela, Marchena, Pinta, Santa Cruz and Santiago), suggesting that this is a widespread interaction. The results reported here support the potential role of lava lizards as pollinators across their radiation, although they may represent a relatively modest contribution when compared with birds and insects. However, we cannot discard that lizards may be ecologically significant for particular plant species and ecosystems given the specific climatic condition and functional diversity of each island.  相似文献   

2.
By tracking the fate of individual seeds from 6 frugivore‐dispersed plants with contrasting seed traits in a fragmented subtropical forest in Southwest China, we explored how rodent seed predation and hoarding were influenced by seed traits such as seed size, seed coat hardness and seed profitability. Post‐dispersal seed fates varied significantly among the 6 seed species and 3 patterns were witnessed: large‐seeded species with a hard seed coat (i.e. Choerospoadias axillaries and Diospyros kaki var. silvestris) had more seeds removed, cached and then surviving at caches, and they also had fewer seeds predated but a higher proportion of seeds surviving at the source; medium‐sized species with higher profitability and thinner seed coat (i.e. Phoebe zhennan and Padus braohypoda) were first harvested and had the lowest probability of seeds surviving either at the source or at caches due to higher predation before or after removal; and small‐seeded species with lower profitability (i.e. Elaeocarpus japonicas and Cornus controversa) had the highest probability of seeds surviving at the source but the lowest probability of seeds surviving at caches due to lower predation at the source and lower hoarding at caches. Our study indicates that patterns of seed predation, dispersal and survival among frugivore‐dispersed plants are highly determined by seed traits such as seed size, seed defense and seed profitability due to selective predation and hoarding by seed‐eating rodents. Therefore, trait‐mediated seed predation, dispersal and survival via seed‐eating rodents can largely affect population and community dynamics of frugivore‐dispersed plants in fragmented forests.  相似文献   

3.
Local extinction or population decline of large frugivorous vertebrates as primary seed dispersers, caused by human disturbance and habitat change, might lead to dispersal limitation of many large‐seeded fruit trees. However, it is not known whether or not scatter‐hoarding rodents as secondary seed dispersers can help maintain natural regeneration (e.g. seed dispersal) of these frugivore‐dispersed trees in the face of the functional reduction or loss of primary seed dispersers. In the present study, we investigated how scatter‐hoarding rodents affect the fate of tagged seeds of a large‐seeded fruit tree (Scleropyrum wallichianum Arnott, 1838, Santalaceae) from seed fall to seedling establishment in a heavily defaunated tropical forest in the Xishuangbanna region of Yunnan Province, in southwest China, in 2007 and 2008. Our results show that: (i) rodents removed nearly all S. wallichianum seeds in both years; (ii) a large proportion (2007, 75%; 2008, 67.5%) of the tagged seeds were cached individually in the surface soil or under leaf litters; (iii) dispersal distance of primary caches was further in 2007 (19.6 ± 14.6 m) than that in 2008 (14.1 ± 11.6 m), and distance increased as rodents recovered and moved seeds from primary caches into subsequent caching sites; and (iv) part of the cached seeds (2007, 3.2%; 2008, 2%) survived to the seedling stage each year. Our study suggests that by taking roles of both primary and secondary seed dispersers, scatter‐hoarding rodents can play a significant role in maintaining seedling establishment of S. wallichianum, and are able to at least partly compensate for the loss of large frugivorous vertebrates in seed dispersal.  相似文献   

4.
The major challenge to adoption of improved forage technologies in the smallholder farming sector is poor accessibility to seed of improved cultivars. Since 2012, the Zimbabwe Crop Livestock Integration for Improved Food Security (ZimCLIFS) project set out to address such challenges through research-for-development initiatives. The main objective was to demonstrate the potential viability of a pasture seed business using a lead farmer approach, farmer-to-farmer technology dissemination, innovation platforms and field demonstrations. Snapshot surveys were used to map forage seed distribution pathways within and outside project areas. Total land area planted to forages from the 2012/13 to 2014/15 seasons increased by 147% from 14.6 ha. In 2013, Mucuna pruriens (mucuna), Lablab purpureus (lablab) and Vigna unguiculata (cowpea) seed produced was 2 250 kg, 120 kg and 4 450 kg, respectively, and by the third season, total yield increased by 163%. Seed diffusion was within and beyond project boundaries, with mucuna (67%) and lablab (43%) seed produced in the 2013/14 season being distributed outside the project area. Highest amounts received by some farmers were US$800 and US$750 for lablab and mucuna, respectively. It was concluded that there is scope to develop formal pasture seed businesses to increase rural industrialisation and provide a pathway out of poverty in the smallholder sector.  相似文献   

5.
Aflatoxin B1 (AFB1) is a common feed contaminant that adversely affects bird performance and product quality. A total of 600 7‐day‐old quail chicks were randomly allotted to eight experimental groups in a completely randomized design with five replicate pens and 15 quails per pen. Experimental treatments including two levels of AFB1 (0 and 2.5 mg/kg) and 4 levels of Nigella sativa (NS) (0, 0.5, 1.0 and 1.5% of diet) were offered from 7 to 35 days of age to quail chicks. Although feeding of AFB1 impaired gain (G) and feed conversion ratio, dietary NS increased G (p < 0.05). Relative weight of bursa of Fabricius increased with incremental levels of NS (p < 0.05). AFB1 decreased the size of heart, but incremental levels of NS increased the relative weight of heart (p < 0.05). The liver hypertrophy was observed in birds receiving AFB1 (p < 0.05). The birds in AFB1 group had smaller testes than other groups (p < 0.05). Hematocrit value in birds fed AFB1 was lower than that in other groups (p < 0.05) and incremental levels of NS increased blood hematocrit (p < 0.05). Amount of malondialdehyde (MDA) in meat samples of the birds fed AFB1 was higher than those did not receive toxin but incremental levels of NS decreased the MDA concentration in affected birds (p < 0.05). AFB1 suppressed the humoral immunity of the birds while NS augmented the antibody titres against sheep red blood cell and Newcastle disease virus antigens (p < 0.05). AFB1 decreased lactic acid bacteria (LAB) and spore‐forming bacteria (SFB) but increased Escherichia coli (E. coli; p < 0.05). However, NS increased LAB and SFB but decreased the E. coli populations (p < 0.05). This study revealed that NS as a biological detoxifier could relatively attenuate the negative effects of AFB1 in quails.  相似文献   

6.
CASE HISTORY: From 26 days of age, an Antipodes Island parakeet (Cyanoramphus unicolor) was noted to have a severe beak deformity and reduced bodyweight gain compared to its nest mate. The bird was euthanised at 43 days of age.

CLINICAL AND PATHOLOGICAL FINDINGS: The beak abnormality consisted of distortion of the right nares and severe shortening resulting in deviation of the upper maxilla to the right and cranially. On sectioning the head, copious mucoid material was found in the infraorbital sinus and the bony sinus architecture was disrupted. Histopathological examination of the infraorbital sinuses revealed a large focus of chronic but active inflammation, bony lysis on the right side and pockets of a mixed population of bacteria.

DIAGNOSIS: Severe beak deformity, likely secondary to bacterial sinusitis.

CLINICAL RELEVANCE: The case illustrates the need to look for underlying aetiologies to beak malformation, particularly in young parrots.  相似文献   

7.
A single nucleotide polymorphism in the equine herpesvirus 1 (EHV-1) DNA polymerase gene (ORF30 A2254 to G) has been associated with clinical signs of equine herpes myeloencephalopathy (EHM). The purpose of our study was to determine the odds ratio for this genetic marker and EHM using a panel of field isolates from North America collected over the past twenty-three years. EHV-1 isolates cultured at the Cornell University Animal Health Diagnostic Laboratory from 1984 to 2007 were retrieved along with their clinical histories. DNA was extracted from these EHV-1 cultures and allelic discrimination was performed using real-time PCR. The results were confirmed by sequencing of the target region in ORF30. PCR and sequencing were in 100% agreement and showed that 19 out of the 176 isolates had the ORF30 G2254 allele (11%), of which16 were EHM cases and 3 respiratory or abortion cases. The odds of having neurologic disease with the ORF30 G2254 genotype were computed as 162 times greater than those with the opposite allele ORF30 A2254 (95% confidence interval: 35–742). Despite this strong statistical significance, 24% (5/21) of horses with neurologic disease in our study population harbored the “non-neurologic” form of the allele (ORF30 A2254), suggesting that other factors may also contribute to the onset of EHM.  相似文献   

8.
Toxoplasma gondii is an intracellular parasite that infects a broad range of animal species and humans. As the main surface antigen of the tachyzoite, SAG1 is involved in the process of recognition, adhesion and invasion of host cells. The aim of the current systematic review study is to clarify the latest status of studies in the literature regarding SAG1-associated recombinant proteins or SAG1-associated recombinant DNAs as potential vaccines against toxoplasmosis. Data were systematically collected from six databases including PubMed, Science Direct, Web of Science, Google Scholar, EBSCO and Scopus, up to 1st of January 2019. A total of 87 articles were eligible for inclusion criteria in the current systematic review. The most common antigens used for experimental cocktail vaccines together with SAG1 were ROP2 and SAG2. In addition, the most parasite strains used were RH and ME49. Freund’s adjuvant and cholera toxin have been predominantly utilized. Furthermore, regarding the animal models, route and dose of vaccination, challenge methods, measurement of immune responses and cyst burden have been discussed in the text. Most of these experimental vaccines induce immune responses and have a high degree of protection against parasite infections, increase survival rates and duration and reduce cyst burdens. The data demonstrated that SAG1 antigen has a high potential for use as a vaccine and provided a promising approach for protecting humans and animals against toxoplasmosis.  相似文献   

9.
10.
为了获得梅花鹿β-防御素-1(sika deer β-defensin-1,siBD-1)cDNA全序列,本试验以梅花鹿舌黏膜组织内提取的总RNA为模板,根据前期已获得的siBD-1 cDNA的已知部分序列设计引物,采用5'-RACE和3'-RACE技术分别扩增5'-和3'-末端序列,将此扩增产物克隆入pMD18-T载体,进行PCR、双酶切鉴定及序列测定与分析。结果表明,成功克隆出长度约为172和299 bp的siBD-1 cDNA 5'-和3'-末端序列,从而得到418 bp的siBD-1 cDNA全序列(GenBank登录号:HM588696.1),其中包含89 bp 5'-非翻译区(UTR)、192 bp的开放阅读框(ORF)、终止密码子TAA、118 bp的3'-UTR和Poly(A)16。同源性比对结果显示,siBD-1 cDNA与水牛的肠防御素(BEBD)同源性最高,为90.6%,与牛(EBD、LAP、TAP、BNBD-4)、山羊(GBD-1、GBD-2)、驯鹿(reBD-1)、绵羊(sBD-1、sBD-2)和骆驼(caBD-1)的防御素cDNA的同源性较高,分别为83.2%、83.1%、87.3%、87.0%、87.5%、87.5%、84.4%、79.9%、77.1%和70.5%;与马(hoBD-1)和猪(pBD-1)的同源性较低,为60.3%和72.4%;而与人(hBD-2)的同源性最低,为16.0%。siBD-1成熟肽由38个氨基酸残基组成,其中包含9个带正电荷的氨基酸残基。  相似文献   

11.
In this study, natural cycling of BoHV-1 infection was investigated in two groups of dairy cattle containing 2120 head. Group 1 comprised 127 animals and they were monitored for BoHV-1 infection virologically and serologically in six consecutive sampling periods. It consisted of naive heifers between 6 and 8 months of age, while in group 2, age, sex and the BoHV-1 serostatus of the animals were disregarded. The animals in group 1 were found to have seroconverted at the second sampling. Results of the serological study showed slight antibody response after natural BoHV-1 infection in the herd and neutralizing titres fell below protective levels in the 6–8 months after the peak. During the 2-year study period, one recurrence was detected after primary infection. Virus isolation studies revealed a cytopathic effect indicative of BoHV-1 in two nasal swabs taken during the fifth sampling period from animals with mild upper respiratory tract symptoms. As the study was carried out under natural conditions, it is not known whether the viruses isolated were from recurrences or re-infections. Data from cross-neutralization tests with herd isolates showed higher antibody response than those with the reference virus. The dynamics of BoHV-1 in both groups were found to be statistically similar.  相似文献   

12.
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14.
A study was conducted to assess the growth performance and nutrient utilization of cross‐bred calves serially infected with Fasciola gigantica and/or supplemented with deoiled mahua seed cake (DMSC) during pre‐patent period of infection. Twenty healthy cross‐bred (Holstein Friesian × Haryana) male calves aged 6–7 months with an initial average live weight of 79.6 ± 2.71 kg were divided into four treatment groups (CON, CON‐INF, DMC and DMC‐INF) of five animals each following randomized block design. DMSC was included in the concentrate mixture of DMC and DMC‐INF groups at 100 g/kg level. Animals of groups CON‐INF and DMC‐INF were given an infection of 200 metacercariae (mc) of F. gigantica as serial infection dose of 50 mc twice weekly over a period of 2 weeks. A metabolism trial at 40–49 days post‐infection and growth trial of 145 days duration were conducted. The average daily gain (ADG) and feed conversion ratio (FCR) were significantly (p < 0.05) lower in CON‐INF group as compared to others. The ADG and FCR were significantly (p < 0.05) higher in DMC‐INF as compared to CON‐INF. The intake and digestibility of nutrients were not affected by serial infection with F. gigantica during pre‐patent period. However, significantly (p < 0.001) higher urinary excretion and significantly (p < 0.001) lower nitrogen balance were observed in CON‐INF group as compared to other three groups. The nitrogen balance was significantly (p < 0.001) improved in DMC‐INF group as compared to CON‐INF group. From the results, it may be deduced that the supplementation of deoiled mahua seed cake at 100 g/kg level in the concentrate mixture has improved the growth performance and nitrogen utilization in cross‐bred calves infected with F. gigantica.  相似文献   

15.
Uncoupling protein 1 (UCP-1) was believed to be an exclusive protein found in the brown adipose tissue of small rodents and humans; however, recent studies show that the expression of UCP-1 protein has been found in the sebaceous glands of the mouse tail and human skin. There are a few reports about the presence of UCP-1 in the sebaceous glands of other rodents, such as the Sunda porcupine (Hystrix javanica), a wild spiny rodent commonly found in Indonesia with a large sebaceous gland. The aim of this study was to identify the presence of UCP-1 in the sebaceous glands on the skin of the Sunda porcupine. The skin from three regions (thoracodorsal, lumbosacral and apex caudal) of eight adult Sunda porcupines was used to detect UCP-1-immunopositive cells through immunohistochemistry. All three regions were found immunopositive to anti-UCP-1 antibody in the sebaceous gland of quill and hair follicles, and the epidermal layer in quill and hair follicles with various intensities. The result of immunohistochemistry revealed that the thoracodorsal and apex caudal region was the most intense immunoreaction followed by the lumbosacral region. These findings proved that the presence of UCP-1 was also identified in the sebaceous glands of other rodent (Hystrix javanica) and regions of the body, which has not been reported previously.  相似文献   

16.
The study was conducted to determine the effect of supplementation with rice bran (RB) and /or noug seed (Guizotia abyssinica) meal (NSM) on feed intake, digestibility, and body weight (BW) change in hay based feeding of Farta sheep. Twenty five yearling Farta rams with a mean initial BW of 19.23 ± 0.28 kg were used in randomized complete block design arranged into five blocks of five animals. The five dietary treatments that consisted of hay alone (T1), hay + RB (T2), hay + mixture of RB and NSM at a ratio of 1:2 (T3), hay + mixture of RB and NSM at a ratio of 2:1 (T4) and hay + NSM (T5) were randomly assigned to each sheep within a block. The supplements were daily offered at 300 g dry matter (DM) head−1 in two equal parts at 800 and 1600 h. Supplementation improved the total DM and acid detergent fiber (ADF) intake (P < 0.05), organic matter (OM) intake (P < 0.01), crude protein (CP) intake (P < 0.001). The apparent digestibility of DM in T5 was higher (P < 0.05) than in T1 and T2 and that of T4 was also higher (P < 0.05) than in T1. The apparent digestibility of CP in T5 and T4 were higher (P < 0.001) than in T1 and T2 and that of T3 and T2 were also higher (P < 0.001) than for T1. The BW gain of experimental sheep was improved (P < 0.01) by supplementation with NSC (T5) and/or its mixtures with RB (T3 and T4). The results of the study showed that supplementation with either of both mixtures of NSM and RB at 43% of total DM intake promoted better feed intake, digestibility and BW gain in Farta sheep.  相似文献   

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18.
Rodent pest population outbreaks occur frequently in grassland ecosystems in northern China. The Mongolian gerbil (Meriones unguiculatus) is a dominant pest rodent which is distributed across the semi‐desert grasslands of Inner Mongolia, China. In 2009, we studied the contraceptive effect of levonorgestrel‐quinestrol (EP‐1), concentration 50 ppm, on a wild Mongolian gerbil population. The one‐off contraceptive treatment was compared with a control group using a semi‐monthly live trapping method in the Ordos Semi‐desert Grassland Region of Inner Mongolia. The results show that juveniles were not recruited in spring in the treatment group. Ratios of juveniles in the control and treatment groups showed significant semi‐monthly differences from spring to summer (one‐way ANOVA, F2, 14= 7.53, P < 0.05). Between both groups, annual fluctuations of juvenile and total population densities were significantly different respectively (F2, 14= 4.64, P < 0.05; F2, 18= 7.72, P < 0.05). The contraceptive EP‐1 delayed the normal reproductive pattern of Mongolian gerbil populations. This suppressed birth rates of gerbil populations, reduced their densities, and changed their age structures. The period of EP‐1 baiting should be extended but it could be an ideal method for controlling Mongolian gerbil populations during each breeding season.  相似文献   

19.
Equine herpesvirus type 1 (EHV-1) is responsible for respiratory disorders, abortion and myeloencephalopathy (EHM) in horses. Two pathotypes of EHV-1 strains are circulating in the field: neurovirulent (N) and non-neurovirulent (NN). For both strains, CD172a+ monocytic cells are one of the main carrier cells of EHV-1 during primary infection, allowing the virus to invade the horse’s body. Recently, we showed that EHV-1 NN strains showed a restricted and delayed replication in CD172a+ cells. Here we characterize the in vitro replication kinetics of two EHV-1 N strains in CD172a+ cells and investigate if the replication of these strains is similarly silenced as shown for EHV-1 NN strains. We found that EHV-1 N replication was restricted to 7–8% in CD172a+ cells compared to 100% in control RK-13 cells. EHV-1 N replication was not delayed in CD172a+ cells but virus production was significant lower (103.0 TCID50/105 inoculated cells) than in RK-13 cells (108.5 TCID50/105 inoculated cells). Approximately 0.04% of CD172a+ cells produced and transmitted infectious EHV-1 to neighbour cells compared to 65% of RK-13 cells. Unlike what we observed for the NN strain, pretreatment of CD172a+ cells with histone deacetylases inhibitors (HDACi) did not influence the replication of EHV-1 N strains in these cells. Overall, these results show that the EHV-1 replication of N strains in CD172a+ cells differs from that observed for NN strains, which may contribute to their different pathogeneses in vivo.  相似文献   

20.
Ischemic acute kidney injury (AKI) is the most key pathological event for accelerating progression to chronic kidney disease through vascular endothelial injury or dysfunction. Thus, it is critical to elucidate the molecular mechanism of endothelial protection and regeneration. Emerging evidence indicates that bone marrow-derived cells (BMCs) contribute to tissue reconstitution in several types of organs post-injury, but little is known whether and how BMCs contribute to renal endothelial reconstitution, especially in an early-stage of AKI. Using a mouse model of ischemic AKI, we provide evidence that incorporation of BMCs in vascular components (such as endothelial and smooth muscle cells) becomes evident within four days after renal ischemia and reperfusion, associated with an increase in stromal cell-derived factor-1 (SDF1) in endothelium and that in CXCR4/SDF1-receptor in BMCs. Notably, anti-CXCR4 antibody decreased the numbers of infiltrated BMCs and BMC-derived endothelium-like cells, but not of BMC-derived smooth muscle cell-like cells. These results suggest that reconstitution of renal endothelium post-ischemia partially depends on a paracrine loop of SDF1-CXCR4 between resident endothelium and BMCs. Such a chemokine ligand-receptor system may be attributable for selecting a cellular lineage (s), required for renal vascular protection, repair and homeostasis, even in an earlier phase of AKI.  相似文献   

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