Transcriptomic comparison of ovarian granulosa cells between adult sheep and prepubertal lambs

Background The oocyte development ability of prepubertal animals is significantly lower than that of adult animals. Granulosa cells (GCs) have an important function on regulation of follicular and oocyte development. Therefore, analysis of GCs characteristics can be used to explore the developmental mechanism of follicles and oocytes. Results In order to understand the possible reasons for the differences in follicles and oocytes development between lambs and adult sheep, we utilized high-throughput sequencing technique to analyze the transcriptome of GCs from follicle-stimulating hormone (FSH) superstimulated adult ewes and prepubertal lambs. Adult ewes were stimulated with FSH for 3 days (group A) and lambs were FSH-stimulated for 2 days (group B) or 3 days (group C). Transcriptome analysis of GCs showed that there were 405 and 159 differentially expressed genes from A vs. B and A vs. C, respectively. The results indicated that prolonging the FSH-stimulation of lambs made the GC state of lambs more similar to the adult sheep, but there were still a large number of differentially expressed genes between adult sheep and lambs. Further analysis showed that many differently expressed genes were implicated in cell proliferation and apoptosis, oocyte development and follicular ovulation. Cellular examination demonstrated that fatty acid binding protein 4 (FABP4), which was highly expressed in lamb GCs, had a potential of promoting cell apoptosis. Cytoplasmic phospholipase A2 (PLA2G4A), which was expressed lowly in lamb GCs, may be responsible for reduced synthesis of prostaglandins in cells and impaired follicle/oocyte development. In contrast, glutathione S-transferase β-1 (GSTT2B) and forkhead boxO6 (FOXO6) had no apparent effect on the proliferation and apoptosis of GCs.

Is vaccination a viable method to control Johne’s disease caused by Mycobacterium avium subsp. paratuberculosis? Data from 12 million ovine vaccinations and 7.6 million carcass examinations in New South Wales, Australia from 1999–2009

Background Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne’s disease (or paratuberculosis), a chronic wasting disease of ruminants and other animals resulting from granulomatous enteritis. There are increasing concerns that MAP is zoonotic. The prevalence of Johne’s disease is increasing worldwide. In an attempt to control an epidemic of ovine Johne’s disease (OJD) in New South Wales (NSW), a government/industry sponsored voluntary vaccination/on-farm management program commenced in 2000. We report herein an observational study of changes in disease prevalence as vaccination progressed, based on abattoir surveillance data for OJD from 1999 to 2009. We also discuss the epidemiological, policy, regulatory, research, economic and sociological elements that contributed to the development of a mature control program, whose aim was to halt the epidemic spread of OJD in a naïve sheep population. Methods NSW was divided into areas of “High” (HPA), “Medium” (MPA) and “Low” (LPA) OJD prevalence. A killed whole cell vaccine (Gudair®) was administered to sheep from 2000 to 2009. Trained examiners evaluated the viscera of adult sheep carcasses at slaughter for gross evidence of OJD. MAP infection was confirmed by histopathology. Principal findings From 2000–2009, 12 million vaccine doses were administered in NSW (91%; 10.9 million in the HPA). Many of the vaccinated flocks were suffering > 5% annual mortality in adult sheep, with some individual flocks with 10–15% losses attributable to OJD. A total of 7.6 million carcasses were examined (38%; 2.9 million from the HPA). Overall, 16% of slaughter consignments (sheep consigned to the abattoir from a single vendor) were positive for OJD, of which 94% were from the HPA. In the HPA, the percentage of animals with lesions attributable to OJD at slaughter fell progressively from 2.4% (10,406/432,860) at commencement of vaccination in 2000 to 0.8% (1,573/189,564) by 2009. Herd immunity from vaccination in the HPA was estimated at 70% by 2009, the target commonly espoused for an effective control program based on vaccination. This coincided with a progressive decrease in reports of clinical disease and mortalities in vaccinated flocks. Significance We show a decrease in the prevalence of lesions attributable to OJD in NSW concomitant with initiation of voluntary vaccination, on-farm management plans, abattoir monitoring and feedback of animal prevalence data to sheep producers. We conclude that a target of ≤ 1% regional prevalence of OJD affected sheep at slaughter is achievable using these interventions.

Identification of Regulatory Functions of LncRNAs Associated With T. circumcincta Infection in Adult Sheep

Several recent studies have demonstrated the role of long non-coding RNAs (lncRNAs) in regulating the defense mechanism against parasite infections, but no studies are available that investigated their relevance for immune response to nematode infection in sheep. Thus, the aim of the current study was to (i) detect putative lncRNAs that are expressed in the abomasal lymph node of adult sheep after an experimental infection with the gastrointestinal nematode (GIN) Teladorsagia circumcincta and (ii) to elucidate their potential functional role associated with the differential host immune response. We hypothesized that putative lncRNAs differentially expressed (DE) between samples from animals that differ in resistance to infection may play a significant regulatory role in response to nematode infection in adult sheep. To obtain further support for our hypothesis, we performed co-expression and functional gene enrichment analyses with the differentially expressed lncRNAs (DE lncRNAs). In a conservative approach, we included for this predictive analysis only those lncRNAs that are confirmed and supported by documentation of expression in gastrointestinal tissues in the current sheep gene atlas. We identified 9,105 putative lncRNA transcripts corresponding to 7,124 gene loci. Of these, 457 were differentially expressed lncRNA loci (DELs) with 683 lncRNA transcripts. Based on a gene co-expression analysis via weighted gene co-expression network analysis, 12 gene network modules (GNMs) were found significantly correlated with at least one of 10 selected target DE lncRNAs. Based on the principle of “guilt-by-association,” the DE genes from each of the three most significantly correlated GNMs were subjected to a gene enrichment analysis. The significant pathways associated with DE lncRNAs included ERK5 Signaling, SAPK/JNK Signaling, RhoGDI Signaling, EIF2 Signaling, Regulation of eIF4 and p70S6K Signaling and Oxidative Phosphorylation pathways. They belong to signaling pathway categories like Cellular Growth, Proliferation and Development, Cellular Stress and Injury, Intracellular and Second Messenger Signaling and Apoptosis. Overall, this lncRNA study conducted in adult sheep after GIN infection provided first insights into the potential functional role of lncRNAs in the differential host response to nematode infection.

A SHORT REVIEW OF DISTRIBUTION OF DICTYOCAULUS FILARIA RUDOLPHI (1809) LUNG NEMATODE IN SHEEP OF DIFFERENT CLIMATE AND LANDSCAPE ZONES OF ARMENIA

Original long-term studies of the authors on the sheep infestation by D. filaria in conditions of pronounced vertical zonal character of climate and landscape belts (300–2000 m above sea level) have shown a presence of wide infestation among all age groups of the animals: in lambs up to 60%, in young sheep up to 57% and in adult sheep up to 45%. Dictyocaulus is also present in moufflons and bezoar goats in Armenia. The main reasons for such a wide infection are the following: • a monoxenous character of D. filaria life cycle, i.e. the parasite being a geohelminth; • its survivability in wide range of biotic conditions; • an insufficient volume of planned prophylaxis measures against dictyocaulosis. A study of seasonal and age dynamics on author's own and literature data was also performed. Dynamics of infestation of lambs with Dictyocaulus is in both lowlands and mountain zones characterized with 2 peaks: summer and autumn ones (prevalence reaching 29.0% for lowlands, 42.0% for highlands in contrast to 5.7% and 2.8% respectively in the spring) with no invasion at start of the year. For young and adult sheep, dynamics of invasion with Dictyocaulus is characterized with high prevalence in spring and autumn periods (start of the year prevalence up to 45.0%, decrease to 15–25.0% in summer, rising to 40.0% and higher in October-December).

Transcriptomics analysis of differentially expressed genes in subcutaneous and perirenal adipose tissue of sheep as affected by their pre- and early postnatal malnutrition histories

Background Early life malnutrition is known to target adipose tissue with varying impact depending on timing of the insult. This study aimed to identify differentially expressed genes in subcutaneous (SUB) and perirenal (PER) adipose tissue of 2.5-years old sheep to elucidate the biology underlying differential impacts of late gestation versus early postnatal malnutrition on functional development of adipose tissues. Adipose tissues were obtained from 37 adult sheep born as twins to dams fed either NORM (fulfilling energy and protein requirements), LOW (50% of NORM) or HIGH (110% of protein and 150% of energy requirements) diets in the last 6-weeks of gestation. From day 3 to 6 months of age, lambs were fed high-carbohydrate-high-fat (HCHF) or moderate low-fat (CONV) diets, and thereafter the same moderate low-fat diet. Results The gene expression profile of SUB in the adult sheep was not affected by the pre- or early postnatal nutrition history. In PER, 993 and 186 differentially expressed genes (DEGs) were identified in LOW versus HIGH and NORM, respectively, but no DEG was found between HIGH and NORM. DEGs identified in the mismatched pre- and postnatal nutrition groups LOW-HCHF (101) and HIGH-HCHF (192) were largely downregulated compared to NORM-CONV. Out of 831 DEGs, 595 and 236 were up- and downregulated in HCHF versus CONV, respectively. The functional enrichment analyses revealed that transmembrane (ion) transport activities, motor activities related to cytoskeletal and spermatozoa function (microtubules and the cytoskeletal motor protein, dynein), and responsiveness to the (micro) environmental extracellular conditions, including endocrine and nervous stimuli were enriched in the DEGs of LOW versus HIGH and NORM. We confirmed that mismatched pre- and postnatal feeding was associated with long-term programming of adipose tissue remodeling and immunity-related pathways. In agreement with phenotypic measurements, early postnatal HCHF feeding targeted pathways involved in kidney cell differentiation, and mismatched LOW-HCHF sheep had specific impairments in cholesterol metabolism pathways. Conclusions Both pre- and postnatal malnutrition differentially programmed (patho-) physiological pathways with implications for adipose functional development associated with metabolic dysfunctions, and PER was a major target.

Sarcoptes scabiei dermatitis in adult sheep: an immunohistochemical study of 34 chronic cases with extensive lesions

Ovine sarcoptic mange is a contagious ectoparasitic skin disease, seen in many countries with sheep production. Although several studies concerning dermatopathology have been published, the local cutaneous immune response to Sarcoptes scabiei has not been studied by immunohistochemistry. The present study aims to evaluate immunohistochemically the adaptive cellular immune response in chronic natural cases with extensive gross lesions. Facial and foot skin biopsies of 32 ewes and 2 rams were obtained, and moreover from the scrotal scabietic lesions of the 2 rams. Each biopsy was bisected and processed for paraffin and cryostat sections. Mites were not observed in the vast majority of skin histology sections. Epidermal hyperplasia and chronic inflammation were the main histopathologic features. The dermal inflammatory infiltrate was mixed, dominated by eosinophils and lymphocytes equally. Tissue sections immunostained with a panel of monoclonal antibodies showed among lymphocytes an almost exclusively T-cell population (CD3+), while CD79a + cells were sparse. T-helper cells (CD4+) were predominant versus T-cytotoxic cells (CD8+) in 4:1 to 5:1 ratios. The mixed inflammatory infiltrate combined with the immunohistochemical findings suggest both a type-I and type-IV hypersensitivity reactions during the chronic course of the disease. Moreover, all these chronic cases in adult sheep are recorded into the hypersensitivity form of sarcoptic mange (“classical or ordinary” scabies) and no cases of the hyperkeratotic form of the disease (“Norwegian or crusted” scabies) were found.

Biological potential cestodes of Echinococcus granulosus in dogs and sheep in the Republic Dagestan

The article is devoted to the study of the biotic potential and the role of the cestode Echinococcus granulosus in the infection of shepherd dogs and sheep in the republic. It has been established that the average intensity of invasion (II) of the causative agent of echinococcosis in shepherd dogs in the surveyed areas (Kizlyarsky, Laksky, Nogaysky, Sergokalinsky, Suleiman – Stalsky, Khasavyurt, Tsumadinsky, Shamilsky, etc.) is 1768 ± 245; 2924 ± 369; 3456 ± 382; 4683 ± 597; 2249 ± 321; 1870 ± 263; 2633 ± 352; 2149 ± 286 specimens / specimen. Infection of adult sheep with echinococcosis occurs in all surveyed areas, with fluctuations in the intensity of invasion (II) from 14.8 ± 1.3 to 21.3 ± 1.9 specimens / specimen, on average 17.56 ± 1.53 specimens. /individual. In sheep of all age groups, with a complete helminthological autopsy, in 1 ml of echinococcal fluid, fertile larvocysts were found in an amount of 20.36 ± 1.15 specimens / individual, except for young sheep, up to 1 year old. In sheep under the age of 2 years, fertile larvocysts of Echinococcus granulosus are found in the amount of 9.2 ± 0.41 specimens / specimen 0.83 ± 0.076 thousand specimens. The average number of fertile larvocysts found in 1 ml of fluid in sheep at the age of up to 3 years is 15.8 ± 0.93 specimens / individual and 1.15 ± 0.098 thousand specimens; up to 4 years old – 20.5 ± 1.17 specimens / individual and 1.92 ± 0.17 thousand specimens; up to 5 years – 27.3 ± 1.69 specimens / individual and 2.58 ± 0.26 thousand specimens; up to 6 years old – 36.7 ± 1.88 specimens / individual and 3.06 ± 0.49 thousand specimens. These data indicate an increase in the role and activity of the ovine variant of the causative agent of echinococcosis Echinococcus granulosus.

Is Vaccination a Viable Method to Control Johne’s Disease Caused by Mycobacterium avium subsp. paratuberculosis? Data from 12 Million Ovine Vaccinations and 7.6 Million Carcass Examinations in New South Wales, Australia from 1999-2009

BackgroundMycobacterium avium subsp. paratuberculosis (MAP) causes Johne’s disease (or paratuberculosis), a chronic wasting disease of ruminants and other animals resulting from granulomatous enteritis. There are increasing concerns that MAP is zoonotic. The prevalence of Johne’s disease is increasing worldwide. In an attempt to control an epidemic of ovine Johne’s disease (OJD) in New South Wales (NSW), a government/industry sponsored voluntary vaccination/on-farm management program commenced in 2000. We report herein an observational study of changes in disease prevalence as vaccination progressed, based on abattoir surveillance data for OJD from 1999 to 2009. We also discuss the epidemiological, policy, regulatory, research, economic and sociological elements that contributed to the development of a mature control program, whose aim was to halt the epidemic spread of OJD in a naïve sheep population.MethodsNSW was divided into areas of “High” (HPA), “Medium” (MPA) and “Low” (LPA) OJD prevalence. A killed whole cell vaccine (Gudair®) was administered to sheep from 2000 to 2009. Trained examiners evaluated the viscera of adult sheep carcasses at slaughter for gross evidence of OJD. MAP infection was confirmed by histopathology.Principal findingsFrom 2000-2009, 12 million vaccine doses were administered in NSW (91%; 10.9 million in the HPA). Many of the vaccinated flocks were suffering > 5% annual mortality in adult sheep, with some individual flocks with 10-15% losses attributable to OJD. A total of 7.6 million carcasses were examined (38%; 2.9 million from the HPA). Overall, 16% of slaughter consignments (sheep consigned to the abattoir from a single vendor) were positive for OJD, of which 94% were from the HPA. In the HPA, the percentage of animals with lesions attributable to OJD at slaughter fell progressively from 2.4% (10,406/432,860) at commencement of vaccination in 2000 to 0.8% (1,573/189,564) by 2009. Herd immunity from vaccination in the HPA was estimated at 70% by 2009. This coincided with a progressive decrease in reports of clinical disease and mortalities in vaccinated flocks.SignificanceWe show a decrease in the prevalence of lesions attributable to OJD in NSW concomitant with initiation of voluntary vaccination, on-farm management plans, abattoir monitoring and feedback of animal prevalence data to sheep producers. We conclude that a target of ≤ 1% regional prevalence of OJD affected sheep at slaughter is achievable using these interventions.

Salmonella enterica subsp. diarizonae Serotype 61:k:1:5:(7) a Host Adapted to Sheep

Salmonella genus is widely distributed in nature and causes a spectrum of diseases in man and animals. Salmonella enterica subsp. diarizonae serotype 61: k: 1,5, (7) (SED) is a host adapted to sheep and its presence as saprophytic bacteria in sheep has been described in different countries. Several studies performed in abattoirs reported the presence of SED in healthy sheep in the intestinal content and also in the respiratory tract. In addition, this microorganism has also been isolated from nostril and faecal samples in healthy live animals. For this reason, this microorganism is considered well adapted to sheep, behaving normally these animals as asymptomatic carriers. However, SED has also been reported causing health disorders such as chronic proliferative rhinitis in adult sheep, abortions, testicular lesions in rams or alimentary tract disorders in young animals. The zoonotic potential of this microorganism is also discussed.