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The Rio Grande Cone is a major fanlike depositional feature in the continental slope of the Pelotas Basin, Southern Brazil. Two representative sediment cores collected in the Cone area were retrieved using a piston core device. In this work, the organic matter (OM) in the sediments was characterized for a continental vs. marine origin using chemical proxies to help constrain the origin of gas in hydrates. The main contribution of OM was from marine organic carbon based on the stable carbon isotope (δ13C-org) and total organic carbon/total nitrogen ratio (TOC:TN) analyses. In addition, the 14C data showed important information about the origin of the OM and we suggest some factors that could modify the original organic matter and therefore mask the “real” 14C ages: (1) biological activity that could modify the carbon isotopic composition of bulk terrestrial organic matter values, (2) the existence of younger sediments from mass wasting deposits unconformably overlying older sediments, and (3) the deep-sediment-sourced methane contribution due to the input of “old” (>50 ka) organic compounds from migrating fluids.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
With still limited information on vitamin requirements and considering that many commercial practices adopt dietary vitamin levels above the values suggested by nutritional tables, this study aimed to assess the effect of administering vitamin supplementation to sows in gestation and lactation and to their litters on the reproductive performance and body condition of the sows and on the performance and immune profile of the litters until slaughter. The trial was split into two phases. The first phase used 104 sows, assigned to be randomized to blocks according to parity, submitted until 21 days of lactation to two treatments: control–standard (standard levels of vitamins) and test–elevated (elevated levels of vitamins). Each sow and its respective farrow were considered an experimental unit. The sows underwent evaluations of body condition score, back fat thickness and reproductive performance. In the second phase, 60 barrows and 60 gilts at 21 days of age and mean initial weight of 5.33 ± 1.5 kg until slaughter at 164 days of age. The piglets were assigned to randomized blocks according to the weight and sex of the animals in a 2 × 2 factorial model, with 10 replicates per treatment, where a pen with three animals represented the experimental unit. Following the same treatments of the first phase, the piglets were evaluated for daily weight gain, daily feed intake, feed conversion, mortality rate and humoral immune response. Vitamin supplementation had no positive effects on the reproductive parameters or body composition of sows. However, it positively impacted the performance of the litters in the early nursery stage, but did not lead to superior effects on the immune responses to vaccination against circovirus or mycoplasma.
The dietary inclusion of feed additives to improve the carcass characteristics of the final product is of great importance for the pork production chain. The aim of our study was to evaluate the effects of the association of ractopamine (RAC) and conjugated linoleic acid (CLA) on the performance traits of finishing pigs during the last 26 days prior to slaughter. In total, 810 commercial hybrid barrows were used. Animals were distributed among treatments according to a randomised block design in a 3 × 3 factorial arrangement, with three RAC levels (0, 5 or 10 ppm) and three CLA levels (0, 0.3 or 0.6%). Pigs fed the diet with 5 ppm RAC had higher average daily feed intake (ADFI) (2.83 kg; P < 0.05) when compared with those fed 10 ppm RAC and the control diet (2.75 and 2.74 kg, respectively). Lower ADFI values (P < 0.01) were observed with the diets containing CLA compared with the control diet with no CLA (2.73 and 2.75 v. 2.85 kg/day, respectively). The average daily weight gain of pigs fed 5 and 10 ppm RAC was +148 and +173 g/dayhigher (P < 0.001), respectively, than those fed the control diet. Dietary RAC levels influenced (P < 0.001) feed conversion ratio (FCR), which was reduced as RAC levels increased, with the pigs fed 10, 5 and 0 ppm RAC presenting FCR values of 2.57, 2.71 and 3.05, respectively. FCR also improved (P < 0.05) with the inclusion of 0.6% CLA relative to the control diet (2.70 v. 2.84, respectively). There was a significant interaction between CLA × RAC levels (P < 0.01) for final BW, loin eye area (LEA) (P < 0.05) and backfat thickness (BT) (P < 0.05). The treatments containing 10 ppm RAC + 0.6% or 0.3% CLA increased LEA and reduced BT. In conclusion, the level of 10 ppm inclusion of RAC increased the overall performance parameters of pigs and therefore improved production efficiency. The combined use of RAC and CLA promoted a lower feed conversion ratio as well as better quantitative carcass traits, as demonstrated by the higher LEA and lower BT. The dietary inclusion of CLA at 0.3% improved feed efficiency, however, without affecting LEA or BT yields.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
The current study evaluated growth performance and digestion responses of finishing bulls fed diets containing 825 g/kg flint maize [dry matter (DM) basis] ground to medium (1.66 mm; MG) or coarse particle sizes (2.12 mm; CG), with added monensin (26 mg/kg; DM basis; MON) or a blend of essential oils (BEO) + exogenous α-amylase (AM; 90 mg/kg + 560 mg/kg commercial product, respectively, DM basis). In Expt 1, 256 Nellore bulls were blocked by initial body weight (BW) (360 ± 11.7 kg) and assigned to 48 pens in a 2 × 2 factorial arrangement of treatments. Effect of a maize particle size × feed additive interaction was not detected for final BW, DM intake (DMI), average daily gain (ADG) and feed efficiency. The DMI was greater for bulls fed BEO + AM v. MON. Final BW and ADG tended to be greater for bulls fed CG than MG maize. An interaction was detected for hot carcass weight which was 11 kg heavier for bulls fed BEO + AM v. MON in diets containing CG, but not MG particle size. In Expt 2, four ruminally cannulated Nellore steers were offered the same treatments as Expt 1, in a 4 × 4 Latin Square design. Intake of most nutrients was greater for steers fed CG than steers fed MG maize. In summary, feeding bulls CG maize increased growth performance and carcass characteristics compared with MG. The combination of BEO + AM resulted in heavier carcass weights compared with MON supplementation when included in diets containing CG maize.
To explore the perceptions of soldiers participating in a US Army Office of The Surgeon General’s worksite health promotion programme (WHPP) on the local food environment within their campus-style workplace.
Focus groups were conducted to evaluate the perceived effectiveness of the WHPP implementation. Further exploration of focus group data through thematic analysis focused on perceived contributions of the military campus-style food environment to soldiers’ nutrition behaviours.
Three US Army installations located in the continental USA.
Active duty soldiers (n 366) participating in one of the fifty-eight focus groups.
Soldiers shared a common belief of self-discipline and personal responsibility as the foothold to nutrition behaviour change. Soldiers described aspects of the military campus-style food environment as factors impeding achievement of optimal nutrition. Collectively, soldiers perceived the proximity and density of fast-food restaurants, lack of healthy alternatives on the installation and the cost of healthy food as inhibitors to choosing healthy foods. Overwhelmingly, soldiers also perceived time constraints as a factor contributing to unhealthy food choices.
Although nutrition behaviour is individually driven, soldiers perceived the military campus-style food environment inhibits healthy decision making. Nutrition programming in military WHPP must integrate food environment changes to improve soldiers’ nutrition behaviour outcomes. Applicable to the military, food choice behaviour studies suggest environmental changes must be appealing to young adults. Considerations for environmental changes should include an increased portion size for healthy options, broadened use of soldiers’ daily food allowances on local produce and increased availability of grab-and-go options.
The establishment of an invasive species depends on reproductive success and dispersion capability in the new environment. One of the striking examples of invasion in urban environments is the mosquito Aedes aegypti Linnaeus, 1762 (Culicidae). The success of this species is primarily attributed to its ability to colonize urban environments, and some of the important adaptive strategies associated with this ability is the preference for humans as a blood source and intense occupation of residential (indoor) environments. This study evaluated the effects of location (indoor vs. outdoor) and water nutrient level (% organic matter) on the oviposition preference of A. aegypti in an urban environment. We used oviposition choice experiments to evaluate mosquito oviposition in containers holding 1:1 vs 1:0 ratios of water: organic matter placed indoors and outdoors. Eggs were sampled once per week for nine weeks. Our results revealed a strong oviposition preference for outdoor containers, with a significant preference for containers with higher concentrations of organic matter during the fifth to ninth weeks. However, mosquitoes occupying indoor environments did not prefer to lay eggs in containers with lower levels of organic matter. A better understanding of the preferences of A. aegypti regarding the nutrient level and location of oviposition containers can increase our understanding of the behavioral factors allowing mosquitoes to utilize anthropogenic environments.
Buffalo milk production has become of significant importance on the world scale, however, there are few studies involving biotechnological tools specifically for buffalo. To verify the effects caused by subclinical mastitis on the components of milk and to study the innate immune system in the udder of dairy buffaloes with subclinical mastitis, we evaluated the levels of expression of the lactoferrin (LTF), tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-8 (IL-8), and toll-like receptors 2 (TLR-2) and 4 (TLR-4) genes in buffaloes with and without subclinical mastitis. Milk samples were collected for the determination of milk components: somatic cell score (SCS), fat, protein, lactose, total solids and solids-not-fat (SNF), as well as for RNA extraction of milk cells, complementary DNA synthesis, and expression profile quantification by quantitative real-time PCR. For gene expression, the ΔΔCt was estimated using contrasts of the target genes expression adjusted for the expression of the housekeeping genes between both groups. Linear regression analysis was performed to determine the relationship between the genes studied and the milk components. Subclinical mastitis induced changes in the fat, lactose and SNF in milk of buffaloes, and the messenger RNA abundance was upregulated for TLR-2, TLR-4, TNF-α, IL-1β and IL-8 genes in milk cells of buffaloes with subclinical mastitis, whereas the LTF gene was not differentially expressed. Results of linear regression analysis showed that TLR-2 gene expression most explains the variation in SCS, and the change in a unit of ΔCt of the TNF-α gene would result in a higher increase in SCS. The study of these immune function genes that are active in the mammary gland is important to characterize the action mechanism of the innate immunity that occurs in subclinical mastitis in dairy buffaloes and may aid the development of strategies to preserve the health of the udder.
Protein is the most costly nutrient in fish feed, and while diets offered in the early stages of development typically have high levels of CP, they do not always correspond to the real requirements of the animals. Thus, research that seeks to learn the true nutritional requirements of fish is fundamental to improving commercial fish culture. The present study evaluated the protein requirements of Nile tilapia (Oreochromis niloticus) under larviculture. Fish performance, gene expression for digestive enzymes and their enzymatic activity and stress response to air exposure were analyzed. Four experimental diets differing in CP level were formulated: 30%, 36%, 42% and 48%. Fish larvae were fed the experimental diets during development and sampled 10, 20 and 30 days after the beginning of the experiment for performance, gene expression and enzymatic activity. At sampling time 30, stress resistance was also evaluated by means of an air exposure test. At sampling time 10, CP levels between 36% and 48% could be used for a better performance. During this period, pepsinogen expression was greater for 30% CP, intermediate for 42% and lower for 36% and 48%. After this initial period, diets of between 30% and 42% CP are recommended for better performance. At sampling time 20, gene expression for digestive enzymes and their enzymatic activity were similar for all diets tested. At sampling time 30, the diet of 42% CP induced both greater pepsinogen expression and pepsin activity. Survival after the air exposure test after 30 days of feeding was influenced by CP level in the diet, with the highest survival being for fish fed with 36% CP. Taken together, the present results demonstrate that dietary CP influences digestive enzyme gene expression and activity, and suggest that the best CP levels for Nile tilapia larviculture vary depending on larval stage.
There have been few studies realized that evaluate the effects of adopting
different nutritional systems in more than one phase of cattle production on
carcass and meat characteristics. This study was realized to evaluate carcass
and meat characteristics from bulls submitted to different nutritional systems
during two production phases. The experiment was conducted at
Figueira’s farm during two production phases: I (cow–calf)
– 80 calves (99.6±2.72 days of age and
109.7±2.99 kg of BW) with their mothers were randomly assigned into
two supplemental diets: cow–calf mineral supplement
(n=40) or cow–calf creep-feeding
(n=40); II (stocker) – the same 80
calves (201.2±2.11 days of age and 190.2±3.37 kg of BW)
were redistributed into two production systems: stocker pasture
(n=40) or stocker feedlot (SF;
n=40). After, all 80 animals were kept on a pasture
system (III) for 290 days, and then finished in a feedlot system (IV) for more
33 days. Then, they were slaughtered at an average 764.2±3.06 days of
age and at 499.2±3.33 kg of final BW. After slaughter, the average
daily gain was calculated, and the carcass and meat characteristics were
measured. The statistical model design used was completely randomized in a
2×2 factorial arrangement (two treatment groups on
cow–calf phase and two treatment groups on stocker phase). The single
effects between the groups in each phase and the interactions between both
phases (cow–calf v. stocker) were analyzed. The
results were compared by Fisher’s test, using the R statistical
software. A cow–calf by stocker phases interaction occurred for
carcass conformation and fiber diameter. For single effects, the greatest
influences observed were in the stocker phase. The feedlot group was slaughtered
17 days earlier, with greater final BW (3.8%), hot carcass weight
(5.7%), average daily gain (6.9%), dressing percentage
(1.8%), carcass length (1.8%), carcass width
(1.5%), longissimus muscle area (4.8%)
and muscle depth (2.3%) than pasture group. The SF group also had
influence on fat color; showing higher L* and lower
b* values. These results reveal that bulls
reared in feedlot at the stocker phase have higher muscle development and that
the stocker phase has the greatest potential to influence carcass
characteristics and meat quality.
Phenotypic differentiation among fish populations may be used for management of distinct stocks and helps in conserving biodiversity. We compared morphometric and meristic characters of the anchovy Anchoa januaria from shallow semi-closed bays between the south-eastern (Tropical, 23°S) and southern (Subtropical, 25°S) Brazilian coast. We hypothesized that differences between habitats and environmental conditions result in morphological divergence between conspecific populations. Fish size did not differ significantly between the two areas. Significant differences in the meristic and morphological characters were detected for individuals between the two areas, with specimens from the Subtropical region having significant larger head height, pectoral fin length and eye diameter compared with those from the Tropical region. Conversely, specimens from the Tropical region had significantly larger maxillary length, mouth length and body height than those from the Subtropical region. The number of rays for the dorsal and pectoral fins were higher for the specimens from the Subtropical region, whereas for the anal fin was higher for individuals from the Tropical region. Different morphological groups between the two regions were depicted by principal component analysis and discriminant function analysis, which suggest that morphological divergence is occurring. Local environmental influences and the lack of genetic interchange are likely to be the causes of such divergence. This is facilitated by the low tolerance of this species to marine waters that prevents connectivity between these stocks/populations.
The main aim of the present study was to examine the association between the Dietary Inflammatory Index (DII®) and academic performance in children.
School-based cross-sectional study. The DII was calculated based on dietary information obtained from a single 24h dietary recall. Academic performance was assessed by school records provided by the administrative services (i.e. Maths and Language).
Porto area (Portugal).
A total of 524 children (277 girls) aged 11·56 (sd 0·86) years.
The DII was associated with academic indicators (standardized β values ranging from −0·121 to −0·087; all P<0·05). Significant differences were found between quartiles of the DII (P<0·05); children in the fourth quartile had significantly lower scores in all academic indicators compared with children in the first quartile (score differences ranging from −0·377 to −0·292) after adjustment for potential confounders.
The inflammatory potential of diet may negatively influence academic performance. Children should avoid the consumption of a pro-inflammatory diet and adhere to a more anti-inflammatory diet to achieve academic benefits.
The anti-leishmania effects of HIV peptidase inhibitors (PIs) have been widely reported; however, the biochemical target and mode of action are still a matter of controversy in Leishmania parasites. Considering the possibility that HIV-PIs induce lipid accumulation in Leishmania amazonensis, we analysed the effects of lopinavir on the lipid metabolism of L. amazonensis promastigotes. To this end, parasites were treated with lopinavir at different concentrations and analysed by fluorescence microscopy and spectrofluorimetry, using a fluorescent lipophilic marker. Then, the cellular ultrastructure of treated and control parasites was analysed by transmission electron microscopy (TEM), and the lipid composition was investigated by thin-layer chromatography (TLC). Finally, the sterol content was assayed by gas chromatography–mass spectrometry (GC/MS). TEM analysis revealed an increased number of lipid inclusions in lopinavir-treated cells, which was accompanied by an increase in the lipophilic content, in a dose-dependent manner. TLC and GC–MS analysis revealed a marked increase of cholesterol-esters and cholesterol. In conclusion, lopinavir-induced lipid accumulation and affected lipid composition in L. amazonensis in a concentration–response manner. These data contribute to a better understanding of the possible mechanisms of action of this HIV-PI in L. amazonensis promastigotes. The concerted action of lopinavir on this and other cellular processes, such as the direct inhibition of an aspartyl peptidase, may be responsible for the arrested development of the parasite.
Different diagnostic interviews are used as reference standards for major depression classification in research. Semi-structured interviews involve clinical judgement, whereas fully structured interviews are completely scripted. The Mini International Neuropsychiatric Interview (MINI), a brief fully structured interview, is also sometimes used. It is not known whether interview method is associated with probability of major depression classification.
To evaluate the association between interview method and odds of major depression classification, controlling for depressive symptom scores and participant characteristics.
Data collected for an individual participant data meta-analysis of Patient Health Questionnaire-9 (PHQ-9) diagnostic accuracy were analysed and binomial generalised linear mixed models were fit.
A total of 17 158 participants (2287 with major depression) from 57 primary studies were analysed. Among fully structured interviews, odds of major depression were higher for the MINI compared with the Composite International Diagnostic Interview (CIDI) (odds ratio (OR) = 2.10; 95% CI = 1.15–3.87). Compared with semi-structured interviews, fully structured interviews (MINI excluded) were non-significantly more likely to classify participants with low-level depressive symptoms (PHQ-9 scores ≤6) as having major depression (OR = 3.13; 95% CI = 0.98–10.00), similarly likely for moderate-level symptoms (PHQ-9 scores 7–15) (OR = 0.96; 95% CI = 0.56–1.66) and significantly less likely for high-level symptoms (PHQ-9 scores ≥16) (OR = 0.50; 95% CI = 0.26–0.97).
The MINI may identify more people as depressed than the CIDI, and semi-structured and fully structured interviews may not be interchangeable methods, but these results should be replicated.
Declaration of interest
Drs Jetté and Patten declare that they received a grant, outside the submitted work, from the Hotchkiss Brain Institute, which was jointly funded by the Institute and Pfizer. Pfizer was the original sponsor of the development of the PHQ-9, which is now in the public domain. Dr Chan is a steering committee member or consultant of Astra Zeneca, Bayer, Lilly, MSD and Pfizer. She has received sponsorships and honorarium for giving lectures and providing consultancy and her affiliated institution has received research grants from these companies. Dr Hegerl declares that within the past 3 years, he was an advisory board member for Lundbeck, Servier and Otsuka Pharma; a consultant for Bayer Pharma; and a speaker for Medice Arzneimittel, Novartis, and Roche Pharma, all outside the submitted work. Dr Inagaki declares that he has received grants from Novartis Pharma, lecture fees from Pfizer, Mochida, Shionogi, Sumitomo Dainippon Pharma, Daiichi-Sankyo, Meiji Seika and Takeda, and royalties from Nippon Hyoron Sha, Nanzando, Seiwa Shoten, Igaku-shoin and Technomics, all outside of the submitted work. Dr Yamada reports personal fees from Meiji Seika Pharma Co., Ltd., MSD K.K., Asahi Kasei Pharma Corporation, Seishin Shobo, Seiwa Shoten Co., Ltd., Igaku-shoin Ltd., Chugai Igakusha and Sentan Igakusha, all outside the submitted work. All other authors declare no competing interests. No funder had any role in the design and conduct of the study; collection, management, analysis and interpretation of the data; preparation, review or approval of the manuscript; and decision to submit the manuscript for publication.
High concentrations of indium (In) and selenium (Se) have been reported in the Neves-Corvo volcanic-hosted massive sulfide deposit, Portugal. The distribution of these ore metals in the deposit is complex as a result of the combined effects of early ore-forming processes and late tectonometamorphic remobilization. The In and Se contents are higher in Cu-rich ore types, and lower in Zn-rich ore types. At the deposit scale, both In and Se correlate positively with Cu, whereas their correlations with Zn are close to zero. This argues for a genetic connection between Cu, In and Se in terms of metal sourcing and precipitation. However, re-distribution and re-concentration of In and Se associated with tectonometamorphic deformation are also processes of major importance for the actual distribution of these metals throughout the whole deposit. Although minor roquesite and other In-bearing phases were recognized, it is clear that most In within the deposit is found incorporated within sphalerite and chalcopyrite. When chalcopyrite and sphalerite coexist, the In content in sphalerite (avg. 1400 ppm) is, on average, 2–3 times higher than in chalcopyrite (avg. 660 ppm). The In content in stannite (avg. 1.3 wt.%) is even higher than in sphalerite, but the overall abundance of stannite is subordinate to either sphalerite or chalcopyrite. Selenium is dispersed widely between many different ore minerals, but galena is the main Se-carrier. On average, the Se content in galena is ~50 times greater than in either chalcopyrite (avg. 610 ppm) or sphalerite (avg. 590 ppm). The copper concentrate produced at Neves-Corvo contains very significant In (+Se) content, well above economic values if the copper smelters recovered it. Moreover, the high In content of sphalerite from some Cu-Zn ores, or associated with shear structures, could possibly justify, in the future, a selective exploitation strategy for the production of an In-rich zinc concentrate.
The properties of the acoustic modes are sensitive to magnetic activity. The unprecedented long-term Kepler photometry, thus, allows stellar magnetic cycles to be studied through asteroseismology. We search for signatures of magnetic cycles in the seismic data of Kepler solar-type stars. We find evidence for periodic variations in the acoustic properties of about half of the 87 analysed stars. In these proceedings, we highlight the results obtained for two such stars, namely KIC 8006161 and KIC 5184732.
Parasites of the genus Trypanosoma are microorganisms that display wide morphological, biological and genetic variability. Here we present the first description of an isolate of the genus Trypanosoma naturally infecting the tick Amblyomma brasiliense. The ticks were collected from a specimen of Tayassu pecari (Queixada, white-lipped peccary) from the Itatiaia National Park, Itatiaia, Rio de Janeiro, Brazil. The isolate was characterized by molecular, morphometric and biological analyses. A Trypanosoma culture was isolated from crushed nymphal and adult ticks, propagated in the tick cell line IDE8 and maintained in L15B culture medium, incubated at 32 °C. The isolate grew well in L15B medium at 30, 32 and 34 °C but not at lower or higher temperatures. The culture remained stable in axenic L15B medium at 30 °C. Cryopreserved cultures retained viability after cryopreservation in liquid nitrogen. Growth in axenic medium and developmental forms of the trypanosomes were analysed. Analysis of the 18S rDNA region confirmed the authenticity of this new species and the nucleotide sequence was deposited in Genbank. The species was named Trypanosoma amblyommi sp. nov. strain C1RJ. Characteristics related to pathogenicity, involvement with vertebrate hosts, epidemiology, developmental cycle and transmission mechanisms are still unknown. Therefore, further studies are necessary to understand the aspects of the biological cycle of T. amblyommi sp. nov.