Susceptible Goats Research Articles

Goat mammary gland metabolism: An integrated Omics analysis to unravel seasonal weight loss tolerance

Seasonal weight loss (SWL), is a major limitation to animal production. In the Canary Islands, there are two dairy goat breeds with different levels of tolerance to SWL: Majorera (tolerant) and Palmera (susceptible). Our team has studied the response of these breeds to SWL using different Omics tools. The objective of this study was to integrate such results in a data driven approach and using dedicated tools, namely the DIABLO method. The outputs of our analysis mainly separate unrestricted from restricted goats. Metabolites behave as “hub” molecules, grouping interactions with several genes and proteins. Unrestricted goats upregulated protein synthesis, along with arginine catabolism and adipogenesis pathways, which are related with higher anabolic rates and a larger proportion of secretory tissue, in agreement with their higher milk production. Contrarily, restricted goats seemingly increased the synthesis of acetyl-CoA through serine and acetate conversion into pyruvate. This may have occurred to increase fatty acid synthesis and/or to use them as an energy source in detriment to glucose, which was more available in the diet of unrestricted goats. Lastly, restricted Palmera upregulated the expression of PEBP4 and GPD1 genes compared to all other groups, which might support their use as putative biomarkers for SWL susceptibility. SignificanceSeasonal weight loss (SWL) is a major issue influencing animal production in the tropics and Mediterranean. By studying its impact on the mammary gland of tolerant and susceptible dairy goat breeds, using Omics, we aim at surveying the tissue for possible biomarkers that reflect these traits. In this study, data integration of three Omics (transcriptomics, proteomics and metabolomics) was performed using bioinformatic tools, to relate putative biomarkers and evaluate all three levels of information; in a novel approach. This information can enhance selection programs, lowering the impact of SWL on food production systems.

Protein interactions network of goat innate immune signalling pathway proteins and Haemonchus contortus excretory-secretory proteins.

Haemonchus contortus (H. contortus) has caused a huge impact on the animal husbandry economy in the world's tropical and subtropical regions. Innate immunity is the first-line of host defence. The host recognizes pathogen-associated molecular patterns (PAMPs) through a variety of pattern recognition receptors (PRRs) and activates downstream signalling pathways to resist pathogens invasion. Therefore, elucidating the immune interaction between host and pathogen is key to understanding how the host resists the pathogen. We identified 1516 protein-protein interactions (PPIs) between goat innate immune signal pathway proteins and H. contortus excretory-secretory proteins (ESPs) by Recombination-based "Library vs. Library" yeast two-hybrid system (RLL-Y2H) and constructed the PPIs network. Among them, the NLR and IL-17 signalling pathways have the most protein interactions. And there were more interaction proteins between NOD1 and MUC5AC proteins in the pathways. Combined with the differentially expressed genes (DEGs) of susceptible and resistant goats identified in the preliminary work of our laboratory, we selected the intersection genes to construct the PPIs network, and TRAF2 appeared as a key protein of goat innate immune signalling pathway. We initially studied the PPIs between goat and H. contortus ESPs, which provides valuable information for better understanding the immune interaction between the goats and the H. contortus.

Comparison of susceptibility of different goat breeds to live attenuated goatpox vaccine

Goatpox in small ruminants is the most acute pox disease in domestic animals, playing an important role in their health. Vaccination and biosecurity are the two main strategies to control the disease in countries where goatpox is enzootic. In this study, the susceptibility and reactions of three pure breeds (Saanen, Alpine, and Murcia-Granada) and two hybrid breeds (Saanen-Mahabadi and Alpine-Mahabadi) vaccinated with live attenuated goatpox vaccine were compared. The first cases of pox lesions (PLs) were reported 21–27 days after vaccination, and the most disease-affected goats were observed in the pure Saanen breed with 89.9% morbidity and 27% mortality. Only pure Saanen and Alpine breeds showed reactions to the goatpox vaccine. The Saanen was much more responsive to the goatpox vaccine than the Alpine. Murcia-Granada and a hybrid of Saanen-Mahabadi and Alpine-Mahabadi breeds vaccinated at the same time presented no symptoms and goat PLs. This sensitivity to live goatpox vaccines suggests that safer vaccines should be used in some breeds. Therefore, inactivated goatpox vaccines may be a good choice for vaccination in susceptible goat breeds.

AN OUTBREAK OF HEARTWATER IN WEST AFRICAN DWARF LAMBS ON PASTURE

An outbreak of Heartwater disease in young West African Dwarf ram/lambs on pasture in Ile-Ife is reported. The outbreak which started 2 weeks after being put to pasture lasted 4 weeks. It affected seven out of 24 lambs put to an ex- perimental pasture. The remaining animals in the unit (about 250) were apparently not af- fected. In 3 of the cases Cowdria ruminantium organisms were demonstrated in the endothelial cells of the jugular vein. Ticks removed from the animals and ground in sterile saline produced Heartwater disease in susceptible goats.

Spatial transmission risk during the 2007-2010 Q fever epidemic in The Netherlands: Analysis of the farm-to-farm and farm-to-resident transmission.

Between 2007 and 2010 a Q fever epidemic in Dutch dairy goat farms caused a large Q fever outbreak in human residents in the southern part of the Netherlands. Here we characterize the transmission of Coxiella burnetii, the aetiological agent of Q fever, between infected and susceptible dairy goat farms by estimating a spatial transmission kernel. In addition, we characterize the zoonotic transmission of C. burnetii by estimating the spatial kernel for transmission from infected farms to neighbouring residents. Whereas the range of between-farm transmission is comparable to the scale of the Netherlands, likely due to long-range between-farm contacts such as animal transport, the transmission risk from farms to humans is more localized, although still extending to 10 km and beyond. Within a range of about 10 km, the transmission risk from an infected goat farm to a single resident is of the same order of magnitude as the farm-to-farm transmission risk per animal in a receiving farm. We illustrate how, based on the estimated kernels, spatial patterns of transmission risks between farms and from farms to residents can be calculated and visualized by means of risk maps, offering further insight relevant to policy making in a one-health context.

The continental atlas of tsetse and African animal trypanosomosis in Nigeria

Tsetse-transmitted trypanosomosis remains a major animal health problem in Nigeria, in a context where changes in land cover, climate and control interventions are modifying its epidemiological patterns. Evidence-based decision making for the progressive control of the disease requires spatially-explicit information on its occurrence and prevalence, as well as on the distribution and abundance of the tsetse vector.In the framework of the continental Atlas of tsetse and African animal trypanosomosis (AAT), a geo-referenced database was assembled for Nigeria, based on the systematic review of 133 scientific publications (period January 1990 - March 2019).The three main species of trypanosomes responsible for the disease (i.e. Trypanosoma vivax, T. congolense and T. brucei) were found to be widespread, thus posing a national-level problem. Their geographic distribution extends beyond the tsetse-infested belt, owing to the combined effect of animal movement and mechanical transmission by non-tsetse vectors. T. simiae, the major trypanosomal pathogen in pigs, T. godfreyi and the human-infective T. brucei gambiense were also reported. AAT was reported in a number of susceptible host species, including cattle, sheep, goats, pigs, camels, horses, donkeys and dogs, while no study on wildlife was identified. Estimates of prevalence are heavily influenced by the sensitivity of the diagnostic techniques, ranging from an average of 3.5% for blood films to 31.0% for molecular techniques.Two riverine tsetse species (i.e. Glossina palpalis palpalis and G. tachinoides) were found to have the broadest geographical range, as they were detected in all six geopolitical zones of Nigeria. By contrast, the distribution of savannah species (i.e. G. morsitans submorsitans and G. longipalpis) appears to be highly fragmented, and limited to protected areas. Very little information is available for forest species, with one single paper reporting on G. fusca congolensis and G. nigrofusca nigrofusca in the Niger Delta region.The future development of a national Atlas of tsetse and AAT, relying on both published and unpublished information, could improve on the present review and provide further epidemiological evidence for decision making.

Assessment of genetic resistance and abomasal tissues expression of Yichang white goat experimentally challenge with Haemonchus contortus infection

Our previous association study revealed the mutation in candidate immune genes (NOD1 & NLRP9) was significantly associated with FEC of Haemonchus contortus infection in Yichang white goats, but the relative expression of mRNA of those genes associated with resistance to H. contortus was not investigated. Aim of the current experiment was to evaluate the susceptible and resistant individuals to nematode infection within the population of Yichang white goat (YWG) and assess the differential level of mRNA expression of those candidate genes in the abomasal tissues of susceptible and resistant goats. Fecal egg count (FEC) was determined using a modified McMaster technique, and the hematological parameter was measured by Mindray auto hematology analyzer. Phenotype data were collected and analyzed using a generalized linear model with SAS statistical program. Field investigate revealed that the prevalence (76%) with maxium parasite load (734.34±84.21epg) of H. contortus occurred in August within the experimental flock FEC in resistant group (103.38±1.20epg) and susceptible group (1180.25±43.53epg) group demonstrated the presence of two distinct goat populations within this breed. Four resistant and four susceptible goats were selected from each group. The parasite infection was established by artificially challenge with 5000 infective L3 larvae of H. contortus. Abomasal tissues were collected from all experimental goats after 42 days of post-infection. FEC, Body weight, packed cell volume, and hemoglobin value were significantly different (P < 0.01) between resistant and susceptible group of goats. Quantitative real-time PCR in abomasal tissues revealed that the expression level of mRNA for NOD1 (P < 0.00001), IFNG (P < 0.0001), NLRP9, TLR8, IL32, (P < 0.001) and IGF1 (P < 0.01) was higher in resistant goat compared to susceptible, except SFTPA1. These findings revealed the presence of genetic resistant individuals to H. contortus within the goat breed and expression of NOD1 and NLRP9 genes proved the positive finding of our previous study. Presence of genetic resistant individuals in Yichang white goat YWG breed could be a good candidate for selective breeding and highly expressed genes related to resistant could be used as biomarkers to develop H. contortus resistant goat population.
 Progressive Agriculture 30 (2): 194-208, 2019

Peste des petits ruminants in Africa: Meta-analysis of the virus isolation in molecular epidemiology studies.

Peste des petits ruminant (PPR) is a highly contagious, infectious viral disease of small ruminant species which is caused by the peste des petits ruminants virus (PPRV), the prototype member of the Morbillivirus genus in the Paramyxoviridae family. Peste des petits ruminant was first described in West Africa, where it has probably been endemic in sheep and goats since the emergence of the rinderpest pandemic and was always misdiagnosed with rinderpest in sheep and goats. Since its discovery PPR has had a major impact on sheep and goat breeders in Africa and has therefore been a key focus of research at the veterinary research institutes and university faculties of veterinary medicine in Africa. Several key discoveries were made at these institutions, including the isolation and propagation of African PPR virus isolates, notable amongst which was the Nigerian PPRV 75/1 that was used in the scientific study to understand the taxonomy, molecular dynamics, lineage differentiation of PPRV and the development of vaccine seeds for immunisation against PPR. African sheep and goat breeds including camels and wild ruminants are frequently infected, manifesting clinical signs of the disease, whereas cattle and pigs are asymptomatic but can seroconvert for PPR. The immunisation of susceptible sheep and goats remains the most effective and practical control measure against PPR. To carry out PPR vaccination in tropical African countries with a very high temperature, a thermostable vaccine using the rinderpest lyophilisation method to the attenuated Nigeria 75/1 PPR vaccine strain has been developed, which will greatly facilitate the delivery of vaccination in the control, prevention and global eradication of PPR. Apart from vaccination, other important questions that will contribute towards the control and prevention of PPR need to be answered, for example, to identify the period when a susceptible naïve animal becomes infectious when in contact with an infected animal and when an infectious animal becomes contagious.

Review: Update on Classical and Atypical Scrapie in Sheep and Goats.

Scrapie is a naturally occurring transmissible spongiform encephalopathy (TSE) or prion disease of sheep and goats. Scrapie is a protein misfolding disease where the normal prion protein (PrPC) misfolds into a pathogenic form (PrPSc) that is highly resistant to enzymatic breakdown within the cell and accumulates, eventually leading to neurodegeneration. The amino acid sequence of the prion protein and tissue distribution of PrPSc within affected hosts have a major role in determining susceptibility to and potential environmental contamination with the scrapie agent. Many countries have genotype-based eradication programs that emphasize using rams that express arginine at codon 171 in the prion protein, which is associated with resistance to the classical scrapie agent. In classical scrapie, accumulation of PrPSc within lymphoid and other tissues facilitates environmental contamination and spread of the disease within flocks. A major distinction can be made between classical scrapie strains that are readily spread within populations of susceptible sheep and goats and atypical (Nor-98) scrapie that has unique molecular and phenotype characteristics and is thought to occur spontaneously in older sheep or goats. This review provides an overview of classical and atypical scrapie with consideration of potential transmission of classical scrapie to other mammalian hosts.

Epidemiology and genetic characterization of Peste des petits ruminants virus in Bangladesh.

Peste des petits ruminants (PPR) is an acute, highly contagious disease responsible for high morbidity and mortality rates in susceptible sheep and goats. Adequate knowledge of the diversity of circulating strains of PPR virus will help livestock authorities choose appropriate vaccines. The objective of this study was to describe the epidemiology of PPR and characterize the strains circulating in Bangladesh. Veterinarians enrolled goats showing signs consistent with PPR, including diarrhoea, fever and respiratory distress, from three veterinary hospitals. Post‐treatment follow up was carried out to ascertain health outcomes of the goats. Faecal and throat swab samples were collected from the goats and tested for PPRV RNA using real‐time reverse transcription polymerase chain reaction (rRT‐PCR). Nucleotide sequence‐based phylogenetic analyses of two structural genes, the nucleocapsid (N gene), and the haemagglutinin (H gene) were studied to determine the genetic variations of PPRV strains. Of the 539 goats enrolled, 38% (203/539) had detectable RNA for PPRV. We were able to follow up with 91% (184/203) of the PPRV infected goats; 44 of them died (24%). PPRV was more frequently identified in the summer (45%) than in the rainy season (29%) (Odds ratio = 1.9, 95% confidence interval: 1.3–3.1). Bangladeshi strains were phylogenetically similar to the lineage IV PPRV strains; showing particularly strong affiliation with Tibetan and Indian strains. PPR is a common viral infection of the goats in Bangladesh, with a high case‐fatality rate. This study confirms the circulation of lineage IV PPRV in the country with unique amino acid substitutions in N and H proteins and provides baseline data for vaccine development and implementation.

Transcriptome analysis reveals common differential and global gene expression profiles in bluetongue virus serotype 16 (BTV-16) infected peripheral blood mononuclear cells (PBMCs) in sheep and goats

Bluetongue is an economically important infectious, arthropod borne viral disease of domestic and wild ruminants, caused by Bluetongue virus (BTV). Sheep are considered the most susceptible hosts, while cattle, buffalo and goats serve as reservoirs. The viral pathogenesis of BTV resulting in presence or absence of clinical disease among different hosts is not clearly understood. In the present study, transcriptome of sheep and goats peripheral blood mononuclear cells infected with BTV-16 was explored. The differentially expressed genes (DEGs) identified were found to be significantly enriched for immune system processes - NFκB signaling, MAPK signaling, Ras signaling, NOD signaling, RIG signaling, TNF signaling, TLR signaling, JAK-STAT signaling and VEGF signaling pathways. Greater numbers of DEGs were found to be involved in immune system processes in goats than in sheep. Interestingly, the DEHC (differentially expressed highly connected) gene network was found to be dense in goats than in sheep. Majority of the DEHC genes in the network were upregulated in goats but down-regulated in sheep. The network of differentially expressed immune genes with the other genes further confirmed these findings. Interferon stimulated genes - IFIT1 (ISG56), IFIT2 (ISG54) and IFIT3 (ISG60) responsible for antiviral state in the host were found to be upregulated in both the species. STAT2 was the TF commonly identified to co-regulate the DEGs, with its network showing genes that are downregulated in sheep but upregulated in goats. The genes dysregulated and the networks perturbed in the present study indicate host variability with a positive shift in immune response to BTV in goats than in sheep.

Molecular Characterization of Foot-and-Mouth Disease Virus Type O from Wild Pig in Bangladesh

Foot-and-mouth disease (FMD) is a disease of all non-avian livestock animals which costs direct and indirect economic burden of 6.5-21 billion USD per year worldwide in endemic countries. In Bangladesh, FMD is endemic and mainly caused by foot-and-mouth disease virus (FMDV) serotypes O, A and Asia1. Among FMD susceptible animals cattle, sheep and goat were reported to be more susceptible to this virus, whereas, pig was reported as amplifier of the virus. To date there is no epidemiological data in Bangladesh defining the circulation of FMDV in pig population. This investigation first reports the circulation of FMDV in wild pigs of Bangladesh, its molecular characterization and genotyping. To pursue this, tissue sample from ruptured vesicles of mammary gland was collected from wild pig suspected to be infected with FMD followed by RT-PCR amplification, sequencing and phylogenetic study of the VP1 gene, which is the most variable region of FMDV genome. The virus was identified as FMDV serotype O and phylogenetically clustered together with India 2001 (Ind2001) lineage under middle-east, south Asia (ME-SA) topotype. Within the clade of Ind2001 lineage, FMDV from pig formed a sub-clade with 2013 sequences of cattle which indicates the phylogenetic relatedness of the virus from pig with circulatory virus in cattle population of Bangladesh in 2013. Pair-wise local alignment of the FMDV type O VP1 sequence of pig with other local cattle FMDV type O VP1 sequences of 2012 and 2013 supported the phylogenetic affiliation of the pig FMDV with the circulatory virus in cattle population of Bangladesh in 2013, whereas nucleotide sequences of cattle FMDV VP1 of 2012 were found to be 7-8% divergent compared to pig FMDV VP1. Phylogenetic and pair-wise alignment data conclusively revealed that (i) homologous circulation of the FMDV type O (Ind2001 lineage) occurs in both animal traits; and (ii) FMDV type O VP1 sequence of pig origin is distantly related to 2012 local FMDV type O VP1 sequences of cattle origin, but closely related to 2013 local cattle FMDV type O VP1.Bangladesh J Microbiol, Volume 31, Number 1-2,June-Dec 2014, pp 41-45

How Antiparasitic Drugs Work-And Sometimes Stop Working!

How Antiparasitic Drugs Work-And Sometimes Stop Working!

Expression of the DRB1*1101 Allele in Meat Goats Pasture Exposed to Haemonchus contortus

The Major Histocompatibility class II complex plays an extremely important role in disease resistance and susceptibility. A mutation in the DRB1*1101 gene of the MHC II has been implicated in parasite resistance in sheep. Evaluation of the DRB1*1101 allele and the role it plays in Haemonchus contortus infected goats has not been addressed. This study evaluated expression of the DRB1*1101 allele in goats naturally infected with Haemonchus contortus infection. Total RNA was isolated from whole blood and RT-PCR (Reverse-Transcriptase Polymerase Chain Reaction) using primers designed to target the conserved regions of the human and sheep DRB1*1101 allele. The expected cDNA product was observed at the 201bp of the targeted DRB1*1101 region and verified by cloning and sequencing. Alignment of the Goat DRB1*1101 sequence showed 92% homology at the transcriptional level and 86% homology at the translational level with sheep. Goats pasture exposed to Haemonchus contortus had elevated (P < 0.05) DRB1*1101 allele expression. Expression was highest (P < 0.05) in Boer goats, lower in Myotonic goats and lowest (P < 0.05) in Spanish goats. Males had higher (P < 0.05) DRB1*1101 expression than females. DRB1*1101 gene expression was higher (P < 0.05) in younger vs. older goats. Goats showing resistance to Haemonchus contortus had lower (P < 0.05) DRB1*1101 expression than susceptible goats. Based on our findings, the DRB1*1101 gene in goats can potentially be used as a genetic marker for either resistance or susceptibility to Haemonchus contortus .

Resistance transferance of Amorimia septentrionalis poisoning in goats by ruminal transferance fluid from goats with induced resistance by the inoculation of sodium monofluoroacetate-degrading bacteria

Amorimia septentrionalis is a sodium monofluoroacetate (MFA) - containing plant that causes sudden death in ruminants. The aim of this study was to determine whether the resistance to A. septentrionalis poisoning in goats conferred by the intra-ruminal inoculation with the MFA-degrading bacteria Ancylobacter dichloromethanicus and Pigmentiphaga kullae can be transferred to susceptible goats by the transfaunation of rumen content. Two groups of 8 goats and 2 goats resistant to A. septentrionalis poisoning were used. Goats in Group 1 received four daily doses of 160ml of rumen content from resistant goats and subsequently ingested 8 daily doses of 5g kg-1 of A. septentrionalis. Goats from Group 2 (control) received only the plant. In Group 1, only 2 goats showed mild tachycardia and mild jugular vein engorgement on the 4th and 5th day, but they subsequently returned to normal, even with the continuation of plant administration. All control goats showed severe signs of intoxication and the plant administration was suspended between the 3rd and 7th day. So, the transfer of ruminal fluid from goats previously inoculated with MFA-degrading bacteria induces resistance to poisoning by A. septentrionalis in susceptible goats.

Toll-like receptor responses to Peste des petits ruminants virus in goats and water buffalo.

Ovine rinderpest or goat plague is an economically important and contagious viral disease of sheep and goats, caused by the Peste des petits ruminants virus (PPRV). Differences in susceptibility to goat plague among different breeds and water buffalo exist. The host innate immune system discriminates between pathogen associated molecular patterns and self antigens through surveillance receptors known as Toll like receptors (TLR). We investigated the role of TLR and cytokines in differential susceptibility of goat breeds and water buffalo to PPRV. We examined the replication of PPRV in peripheral blood mononuclear cells (PBMC) of Indian domestic goats and water buffalo and demonstrated that the levels of TLR3 and TLR7 and downstream signalling molecules correlation with susceptibility vs resistance. Naturally susceptible goat breeds, Barbari and Tellichery, had dampened innate immune responses to PPRV and increased viral loads with lower basal expression levels of TLR 3/7. Upon stimulation of PBMC with synthetic TLR3 and TLR7 agonists or PPRV, the levels of proinflammatory cytokines were found to be significantly higher while immunosuppressive interleukin (IL) 10 levels were lower in PPRV resistant Kanni and Salem Black breeds and water buffalo at transcriptional level, correlating with reduced viralloads in infected PBMC. Water buffalo produced higher levels of interferon (IFN) α in comparison with goats at transcriptional and translational levels. Pre-treatment of Vero cells with human IFNα resulted in reduction of PPRV replication, confirming the role of IFNα in limiting PPRV replication. Treatment with IRS66, a TLR7 antagonist, resulted in the reduction of IFNα levels, with increased PPRV replication confirming the role of TLR7. Single nucleotide polymorphism analysis of TLR7 of these goat breeds did not show any marked nucleotide differences that might account for susceptibility vs resistance to PPRV. Analyzing other host genetic factors might provide further insights on susceptibility to PPRV and genetic polymorphisms in the host.

Expression of The Transient Receptor Potential Channel 4 (TRPC4) Gene in Goats Naturally Exposed to Haemonchus contortus Infection

Expulsion of gastrointestinal nematodes (GIN) requires gut contractions and glycoprotein hyper-secretion for detachment from the gut wall. The Transient receptor potential cation channels (TRPC) facilitates contraction of smooth muscle. A mutation in the TRPC4 of mice significantly reduces contraction and motility of the intestine. Thus far, the correlation between TRPC4 and GIN infection has not been evaluated in goats or any other species. This study evaluated gene expression of TRPC4 in Haemonchus contortus exposed resistant goats. Goats that were naturally susceptible and resistant to Haemonchus contortus were sacrificed and intestinal tissues collected. From conserved regions of human, mouse, rat, and bovine TRPC4 gene alignments, oligonucleotide primers were generated using CLC Main Workbench bioinformatics software. The RT-PCR and quantitative real time pcr were performed using total RNA extracted from intestinal tissues. The expected 388bp cDNA product was amplified and sequenced. The goat TRPC4 showed 88 and 87% homology to rat and mouse and 98%, 92%, 91% and 90% homology to the bovine, horse, pig and human TRPC4 genes, respectively. The TRPC4 expression increased (P<0.05) in naturally susceptible goats. There were breed and gender effects (P<0.05) on TRPC4 expression. A strong (P<0.05) correlation was evident when the variables TRPC4 gene expression, clinical anemia, and parasite load were compared in goats. These data indicate that TRPC4 may aid in elucidation of the mechanism of action of the TRPC genes involved in gastrointestinal contraction and motility and their link to GIN infection.

Intoxicação por Amorimia spp. em ruminantes

No Brasil, um dos grupos mais importantes de plantas tóxicas é o das que causam morte súbita associada ao exercício. Integram esse grupo, plantas das famílias Rubiaceae, Bignoniaceae e Malpighiaceae. A nomenclatura de algumas plantas da família Malpighiaceae designadas anteriormente como Mascagnia foram reclassificadas dentro do gênero Amorimia. Dentre as espécies tóxicas de Amorimia no Brasil, encontram-se Amorimia amazonica, Amorimia exotropica, Amorimia pubiflora, Amorimia rigida, Amorimia septentrionalis, Amorimia sp. (complexo Mascagnia rigida; Mascagnia aff. rigida) e uma planta identificada como Mascagnia sepium, que provavelmente se trata de Amorimia amazonica. Em todas essas espécies, foi determinado que o princípio ativo é o monofluoroacetato de sódio (MFA). Outra espécie tóxica, Amorimia concinna, causa morte súbita em bovinos na Colômbia, mas não tem sido estabelecido que contenha MFA. Atualmente, as únicas alternativas para o controle da intoxicação são a utilização de herbicidas, a remoção manual das plantas ou o uso de cercas para evitar que os animais tenham acesso às plantas. Pesquisas demonstraram a possibilidade de utilizar a técnica de aversão condicionada para evitar que os animais ingiram A. rigida. Foi demonstrado que caprinos aumentam consideravelmente a resistência à intoxicação mediante a ingestão de quantidades não tóxicas de A. septentrionalis ou por transfaunação de conteúdo ruminal de animais resistentes para animais susceptíveis. Bactérias que hidrolisam MFA foram isoladas do solo, de folhas de A. septentrionalis e Palicourea aeneofusca e do rúmen de caprinos, sugerindo que a intoxicação possa ser prevenida pela inoculação intra-ruminal dessas bactérias.

Scrapie e seu diagnóstico diferencial em ovinos no Mato Grosso do Sul

Scrapie é uma doença infecciosa, neurodegenerativa fatal, causada pelo príon scrapie (PrPsc). Apresenta-se tanto na forma clássica em ovinos e caprinos geneticamente susceptíveis quanto na forma atípica em ovinos. A primeira notificação oficial do Brasil à Organização Mundial de Saúde Animal (OIE), um caso da forma clássica diagnosticado no Rio Grande do Sul ocorreu em 1985, mas a doença já havia sido diagnosticada no mesmo Estado em 1978. Este trabalho objetivou descrever dois surtos de Scrapie em ovinos em Mato Grosso do Sul (MS), Brasil e investigar, por meio de imuno-histoquímica (IHQ) a presença de PrPsc no Sistema Nervoso Central (SNC) de ovinos examinados entre 2003 e 2010. Na primeira parte observaram-se dois ovinos com sinais clínicos típicos de scrapie, detalhando-se os sinais neurológicos, dados epidemiológicos, histopatológicos e amostras teciduais em duplicata desses ovinos foram encaminhadas para realização de diagnóstico de Raiva e para diagnóstico IHQ para príon. Na segunda parte realizou-se levantamento de laudos de necropsia e diagnósticos histopatológicos de ovinos, no período de maio de 2003 a março de 2010. Amostras de sistema nervoso central de 51 casos foram selecionados, incluindo os dois já com diagnóstico de Scrapie mencionados acima; os tecido de todos esses ovinos foram submetidos à IHQ para detecção de proteína priônica. Os 49 ovinos avaliados apresentaram resultado negativo na IHQ para príon.

Interleukin 13 as a Biomarker for Parasite Resistance in Goats Naturally Exposed to Haemonchus contortus

Gut expulsion of some mammalian nematodes requires IL-13 secreted by Th2 cells. Interleukin 13 enhances gut contractions and glycoprotein hyper-secretion that propel parasites to detach from the gut wall. Haemonchus contortus is a gastrointestinal blood sucking nematode of small ruminants. This study evaluated expression of IL-13 in selected parasite resistant Spanish and Myotonic goats. Whole blood, and abomasal and intestinal tissues were harvested from goats exhibiting susceptibility and resistance to Haemonchus contortus through standard and molecular detection methods. An indirect Enzyme Linked Immunosorbent Assay was performed to determine IL-13 expression. Results showed that IL-13 was expressed 70% more in intestinal than abomasal tissues. Parasite resistant goats expressed more IL-13 than susceptible goats. These data indicate that IL-13 expression may be useful as a biomarker for resistance to Haemonchus contortus infection in goats, allowing IL-13 based anthelmintic drug development and goat producers the ability to select parasite resistant animals.