scholarly journals De Novo Transcriptome Assembly and Annotation of Liver and Brain Tissues of Common Brushtail Possums (Trichosurus vulpecula) in New Zealand: Transcriptome Diversity after Decades of Population Control

Genes ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 436 ◽  
Author(s):  
Arsalan Emami-Khoyi ◽  
Shilpa Pradeep Parbhu ◽  
James G. Ross ◽  
Elaine C. Murphy ◽  
Jennifer Bothwell ◽  
...  

The common brushtail possum (Trichosurus vulpecula), introduced from Australia in the mid-nineteenth century, is an invasive species in New Zealand where it is widespread and forms the largest self-sustained reservoir of bovine tuberculosis (Mycobacterium bovis) among wild populations. Conservation and agricultural authorities regularly apply a series of population control measures to suppress brushtail possum populations. The evolutionary consequence of more than half a century of intensive population control operations on the species’ genomic diversity and population structure is hindered by a paucity of available genomic resources. This study is the first to characterise the functional content and diversity of brushtail possum liver and brain cerebral cortex transcriptomes. Raw sequences from hepatic cells and cerebral cortex were assembled into 58,001 and 64,735 transcripts respectively. Functional annotation and polymorphism assignment of the assembled transcripts demonstrated a considerable level of variation in the core metabolic pathways that represent potential targets for selection pressure exerted by chemical toxicants. This study suggests that the brushtail possum population in New Zealand harbours considerable variation in metabolic pathways that could potentially promote the development of tolerance against chemical toxicants.

Author(s):  
Arsalan Emami-Khoyi ◽  
Shilpa Parbhu ◽  
James Ross ◽  
Elaine Murphy ◽  
Jennifer Bothwell ◽  
...  

The New Zealand brushtail possum (Trichosurus vulpecula), introduced from Australia in the 1850s, is an invasive species that is widespread throughout New Zealand and forms the largest self-sustained reservoir of bovine tuberculosis (Mycobacterium bovis) in the wild. Conservation and agricultural authorities regularly apply a series of population control measures to suppress brushtail possum populations. The evolutionary consequence of more than half a century of intensive population control operations on the species genomic diversity and population structure is hindered by a paucity of available genomic resources for the species. This study is the first to characterise the functional content and diversity of brushtail possum liver and brain cerebral cortex transcriptomes. Raw sequences from hepatic cells and cerebral cortex were assembled into 58,001 and 64,735 transcripts in hepatic cells and cerebral cortex, respectively. Functional annotation and polymorphism assignment of the assembled transcripts demonstrated a considerable level of variation in the core metabolic pathways that represent potential targets for selection pressure exerted by chemical toxicants. This study suggests that the brushtail possum population in New Zealand harbours considerable levels of variation in metabolic pathways that could potentially promote the development of tolerance against chemical toxicants.


2013 ◽  
Vol 40 (7) ◽  
pp. 561 ◽  
Author(s):  
Peter J. Sweetapple ◽  
Wendy A. Ruscoe ◽  
Graham Nugent

Context Efforts to protect or restore degraded plant communities by population control of invasive herbivores frequently fail to achieve their goals. Aims We seek to quantify changes in diet of an introduced herbivore, the brushtail possum (Trichosurus vulpecula), following population control, and determine how these may contribute to variable responses in plant condition. Methods Stomach contents of possums from five areas of indigenous forest in northern New Zealand were analysed to measure diet before and after the application of possum control. Key results The contribution of fruit, and foliage of some early successional forest species, to total possum diet increased up to 27-fold following possum population control. This was accompanied by declines in consumption of the main pre-control possum foods (foliage from common canopy trees). Dietary changes were a combination of an immediate response to control (1 year) and a strengthening of these initial changes with increasing time since control. Conclusions Possums in the study areas changed diet following population control, from a diet dominated by foliage of common canopy tree species to one dominated by fruits, and foliage of uncommon early successional plants. Pest control instantaneously increased the per capita availability of all foods, and probably permitted absolute increases in some foods through plant recovery, enabling possums to substitute scarce, high-preference foods for abundant but less preferred canopy foliage. Implications Following control of a pest herbivore, dietary changes reduce benefits for the most vulnerable preferred plant foods, but enhance benefits for less favoured plants. Intense pest control can permit some recovery of highly preferred foods, despite increased per capita consumption of these foods by survivors of control.


2011 ◽  
Vol 140 (6) ◽  
pp. 1036-1047 ◽  
Author(s):  
G. NUGENT ◽  
J. WHITFORD ◽  
I. J. YOCKNEY ◽  
M. L. CROSS

SUMMARYIn New Zealand, bovine tuberculosis (bTB) is present in domestic cattle and deer herds primarily as the result of on-going disease transmission from the primary wildlife host, the brushtail possum (Trichosurus vulpecula). However, bTB is also present in other introduced free-ranging mammalian species. Between 1996 and 2007, we conducted a series of studies to determine whether poison control of possum populations would have any effect on the prevalence ofMycobacterium bovisinfection in sympatric feral pigs (Sus scrofa). We compared trends in the prevalence of bTB infection in feral pigs in six study areas: possum numbers were reduced in three areas, but not in the other three, effectively providing a thrice-replicated before-after-control-intervention design. Before possum control, the overall prevalence of culture-confirmedM. bovisinfection in feral pigs was 16·7–94·4%, depending on area. Infection prevalence varied little between genders but did vary with age, increasing during the first 2–3 years of life but then declining in older pigs. In the areas in which possum control was applied,M. bovisprevalence in feral pigs fell to near zero within 2–3 years, provided control was applied successfully at the whole-landscape scale. In contrast, prevalence changed much less or not at all in the areas with no possum control. We conclude that feral pigs in New Zealand acquireM. bovisinfection mainly by inter-species transmission from possums, but then rarely pass the disease on to other pigs and are end hosts. This is in contrast to the purported role of pigs as bTB maintenance hosts in other countries, and we suggest the difference in host status may reflect differences in the relative importance of the oral route of infection in different environments. Despite harbouringM. bovisinfection for a number of years, pigs in New Zealand do not sustain bTB independently, but are good sentinels for disease prevalence in possum populations.


2019 ◽  
Vol 43 (2) ◽  
Author(s):  
Ron Jackson ◽  
D.U. Pfeiffe ◽  
T Porphyre ◽  
C Sauter-Louis ◽  
L.A.L. Corner ◽  
...  

1995 ◽  
Vol 22 (5) ◽  
pp. 579 ◽  
Author(s):  
SE Jolly ◽  
RJ Henderson ◽  
C Frampton ◽  
CT Eason

The common brushtail possum (Trichosurus vulpecula), an introduced pest in New Zealand, is susceptible to cholecalciferol (vitamin D3), which is marketed as a rodenticide in many countries. To evaluate cholecalciferol for possum control we offered 242 caged adult possums cereal pellets containing cholecalciferol on its own or with calcium carbonate. Mortality was recorded for two weeks after presentation. For cholecalciferol on its own the LD50 was 16.8 mg kg-1 (95% confidence interval 11.6-21.9 mg kg-1), but the addition of calcium carbonate reduced this to 9.8 mg kg-1 (95% confidence interval 7.0-12.7 mg kg-1). When the sexes were analysed separately, the reduction of the LDS0 by the addition of calcium carbonate was significant only in females. The addition of calcium carbonate appeared to result in a more predictable outcome as shown by the reduced confidence intervals. For possum control, adding calcium carbonate to cholecalciferol bait would improve the bait's efficacy, decrease the amount of toxic material needed, and reduce the cost of bait production.


2012 ◽  
Vol 153 ◽  
pp. 143-152 ◽  
Author(s):  
Christopher Jones ◽  
Mandy Barron ◽  
Bruce Warburton ◽  
Morgan Coleman ◽  
Philip O’B. Lyver ◽  
...  

2020 ◽  
Author(s):  
Shao hudie ◽  
Yu Fu ◽  
Pan Zhang ◽  
Chunping You ◽  
Chuanren Li

Abstract Background: Mulberry is an important crop for sericulture and root-knot nematode infection is a major factor limiting its production. Understanding the interaction mechanism of mulberry and nematode is important for the control of infection. Results: Through sequencing and de novo transcriptome assembly from root samples of resistant and susceptible mulberry cultivars at different stages after infection with the nematode, Meloidogyne enterolobii, we assembled a total of 55,894 unigenes, among which 33,987 were annotated the in Nr, SWISS-PROT, KEGG, and KOG databases. According to GO and pathway enrichment analysis of differentially expressed genes (DEGs), key genes were involved in hormone metabolic processes, plant hormone signal transduction, flavonoid biosynthesis, phenylpropanoid biosynthesis, and peroxisomal and photosynthetic pathways. Analysis of key trends in co-expression networks, indicated that expression of unigenes 0015083, 0073272, 0004006, and 0000628 was positively correlated with resistance to M. enterolobii. Unigene 0015083 encodes tabersonine 16-O-methyltransferase, ROMT, which is involved in alkaloid biosynthesis. Unigene 0073272 encodes a transcription factor, which contributes to nitric oxide accumulation during plant immune responses. Unigenes 0004006 and 0000628 encode the ERF and MYB transcription factors, respectively, involved in plant hormone signaling. To verify the accuracy of transcriptome sequencing results, 21 DEGs were selected for RT-qPCR verification; the results confirmed the reliability of the sequencing data. Conclusions: The results of the present study increase understanding of and provide insights into the resistance mechanisms and candidate genes involved in mulberry-M. enterolobii interaction. Thus, our data will contribute to the development of effective control measures against this pathogen.


2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
G. Nugent ◽  
I. J. Yockney ◽  
E. J. Whitford ◽  
M. L. Cross

In New Zealand, wild pigs acquireMycobacterium bovisinfection by scavenging tuberculous carrion, primarily carcasses of the main disease maintenance host, the brushtail possum (Trichosurus vulpecula). We investigated the utility of captive-reared, purpose-released pigs as sentinels for tuberculosis (TB) following lethal possum control and subsequent population recovery. Within 2-3 years of possum control by intensive poisoning, TB prevalence and the incidence rate ofM. bovisinfection in released sentinel pigs were lower than in an adjacent area where possums had not been poisoned. Unexpectedly, TB did not decline to near zero levels among pigs in the poisoned area, a fact which reflected an unanticipated rapid increase in the apparent abundance of possums. Monitoring infection levels among resident wild pigs confirmed that TB prevalence, while reduced due to possum control, persisted in the poisoned area at >20% among pigs born 2-3 years after poisoning, while remaining >60% among resident wild pigs in the nonpoisoned area. When fitted with radio-tracking devices, purpose-released pigs provided precise spatial TB surveillance information and facilitated effective killing of wild pigs when employed as “Judas” animals to help locate residents. Sentinel pigs offer value for monitoring disease trends in New Zealand, as TB levels in possums decline nationally due to large-scale possum control.


Data in Brief ◽  
2019 ◽  
Vol 27 ◽  
pp. 104577
Author(s):  
Daniel J. White ◽  
Katherine Trought ◽  
Brian Hopkins

Sign in / Sign up

Export Citation Format

Share Document