Large animal models for Huntington's disease research.

Huntington's disease (HD) is a hereditary neurodegenerative disorder for which there is currently no effective treatment available. Consequently, the development of appropriate disease models is critical to thoroughly investigate disease progression. The genetic basis of HD involves the abnormal expansion of CAG repeats in the huntingtin ( HTT) gene, leading to the expansion of a polyglutamine repeat in the HTT protein. Mutant HTT carrying the expanded polyglutamine repeat undergoes misfolding and forms aggregates in the brain, which precipitate selective neuronal loss in specific brain regions. Animal models play an important role in elucidating the pathogenesis of neurodegenerative disorders such as HD and in identifying potential therapeutic targets. Due to the marked species differences between rodents and larger animals, substantial efforts have been directed toward establishing large animal models for HD research. These models are pivotal for advancing the discovery of novel therapeutic targets, enhancing effective drug delivery methods, and improving treatment outcomes. We have explored the advantages of utilizing large animal models, particularly pigs, in previous reviews. Since then, however, significant progress has been made in developing more sophisticated animal models that faithfully replicate the typical pathology of HD. In the current review, we provide a comprehensive overview of large animal models of HD, incorporating recent findings regarding the establishment of HD knock-in (KI) pigs and their genetic therapy. We also explore the utilization of large animal models in HD research, with a focus on sheep, non-human primates (NHPs), and pigs. Our objective is to provide valuable insights into the application of these large animal models for the investigation and treatment of neurodegenerative disorders.

Trichostrongylus colubriformis infection damages intestine brush board cells and could negatively impact postabsorptive parameters of Santa Ines lambs.

This study aimed to evaluate histological, digestive and postabsorptive physiological parameters in Santa Ines lambs infected with Trichostrongylus colubriformis and fed different levels of phosphorus. Therefore, eighteen Santa Ines, castrated male, six-month old, healthy lambs (initial body weight 22.4 ± 2.7 kg) were distributed in one of four treatments arranged in a 2 × 2 split-plot arrangement: Sufficient dietary P level and uninfected (SPui; n = 4), Sufficient dietary P level and infected (SPi; n = 5), Deficient dietary P level and uninfected (DPui; n = 4), Deficient dietary P level and infected (DPi; n = 5). Infected lambs received, orally, a single pulse dose of 40.000 T. colubriformis infective larval stage (L3). Animals were fed Tifton 85 hay (Cynodon ssp.; 60%), and cassava meal and maize gluten meal (40%). Measurement of nutrient apparent digestibility and nitrogen metabolism were performed in individual metabolic stalls. To achieve the trial results, it was measured methane emissions in respiratory chambers, urine purine derivatives, ruminal short-chain fatty acids (SCFA), histological cuts of duodenal mucosal tissues and passage rates fluxes, analyzed by external (Yb, Cr, and Co) and internal (iNDF) markers. Statistical procedures were performed in R studio. The fixed main effects of treatment and the interactions were tested by ANOVA, and means compared by Duncan's test at 5% significance. Apparent digestibility was not affected by treatments, however, nitrogen retained decreased (P < 0.01) and urinary nitrogen losses increased (P < 0.01) in infected animals. Small intestine digesta content, empty segment weight, and length were higher in infected animals (P < 0.05). Passage rate was not majorly affected by infection or dietary P levels. Methane emissions, SCFA concentrations, and purine derivative excretion were also not affected by treatments. Regarding the histology, the vilosity weight (P < 0.05), and crypt depth (P < 0.01) decreased in infected animals. In conclusion, T. colubriformis infection can damage intestinal mucosa and affect nitrogen metabolism, but did not affect the digesta transit, and nutrient digestibility. The P dietary levels did not promote any modification in GIT physiological parameters tested in this study.

Combinatorial treatment of brain samples from sheep with scrapie using sodium percarbonate, sodium dodecyl sulfate, and proteinase K increases survival time in inoculated susceptible sheep.

The agent of scrapie is resistant to most chemical and physical methods of inactivation. Prions bind to soils, metals, and various materials and persist in the environment confounding the control of prion diseases. Most methods of prion inactivation require severe conditions such as prolong exposure to sodium hypochlorite or autoclaving, which may not be suitable for field conditions. We evaluated the efficacy of a combinatorial approach to inactivation of US scrapie strain x124 under the mild conditions of treating scrapie-affected brain homogenate with sodium percarbonate (SPC), sodium dodecyl sulfate (SDS), or in combination followed by proteinase K (PK) digestion at room temperature. Western blot analysis of treated brain homogenate demonstrates partial reduction in PrPSc immunoreactivity. Genetically susceptible VRQ/ARQ Suffolk sheep were oronasally inoculated with 1 g of SPC (n = 1), SDS (n = 2), SDS + PK (n = 2), and SPC + SDS + PK (n = 4) treated brain homogenate. Sheep were assessed daily for clinical signs, euthanized at the development of clinical disease, and tissues were assessed for accumulation of PrPSc. Scrapie status in all sheep was determined by western blot, enzyme immunoassay, and immunohistochemistry. Mean incubation periods (IPs) for SPC (11.9 months, 0% survival), SDS (12.6 months, 0% survival), SDS + PK (14.0 months, 0% survival), and SPC + SDS + PK (12.5 months, 25% survival) were increased compared to positive control sheep (n = 2, 10.7 months, 0% survival) by 1.2, 1.9, 3.3, and 1.8 months, respectively. Treatment did not influence PrPSc accumulation and distribution at the clinical stage of disease. Differences in mean IPs and survival indicates partial but not complete reduction in scrapie infectivity.

BHBA regulates the expressions of lipid synthesis and oxidation genes in sheep hepatocytes through the AMPK pathway.

Pregnancy toxemia (PT) is the most frequent metabolic disease of sheep during late pregnancy, which can lead to enormous economic losses in sheep farm industry. However, the underlying mechanism of PT in sheep has not been fully elucidated. High levels of ß-hydroxy butyric acid (BHBA) exist in PT sheep. The AMP-activated protein kinase (AMPK) pathway plays a major role in regulating liver function. The aim of this study was to explore the effects of gradient concentrations of BHBA on lipid metabolism of sheep hepatocytes and the underlying molecular mechanism in vitro. The results showed that 0.6, 1.2 mmol/L BHBA could activate AMPKα, promoted the expressions of peroxisome proliferator-activated receptor alpha (PPARα) and its target genes, and inhibited the expressions of sterol regulatory element binding protein-1c (SREBP-1c) as well as its downstream genes. When the concentration of BHBA was beyond 1.2 mmol/L, the expressions of the above-mentioned proteins and genes were just the opposite. However, the expressions of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) did not change significantly. The levels of very low density lipoprotein (VLDL), triglyceride (TG) and cholesterol (T-CHOL) showed a gradually increasing trend with the increase of BHBA concentration. According to the results above, it demonstrates that high levels of BHBA can inhibit the expression of the AMPK pathway and cause lipid metabolism disorders in sheep hepatocytes, which may lead to the occurrence of PT.

miR-509-5p anti-infection response for mycoplasma pneumonia in sheep by targeting NF-κB pathway.

MicroRNAs play a key role in Mannan-binding lectin-mediated resistance to Mycoplasma ovipneumoniae pneumonia, by regulating the translation of mRNAs of target genes, thereby regulating the immune response. Additionally, TRAF6 is a key molecule in Toll-like receptor signal transduction, which mediates inflammation and apoptosis signaling pathways and is widely involved in inflammation and immune response. While the molecular regulation mechanism has not been reported. In this study, we screened differentially expressed miRNAs and genes of Anti-infection for M. pneumonia on Sheep, through relevant bioinformatics analysis. Further, the effect of differential expression of NF-κB signaling pathway related genes on the molecular mechanism of M. pneumonia was detected. We used miRNA-mRNA integrated analysed, the target gene TRAF6 of miR-509-5p was selected. TRAF6 dual luciferase reporter vector was co-transfected into HEK 293T cells and primary sheep respiratory mucosal epithelial cells to detect changes in luciferase activity. qRT-PCR was used to analyze the effect of miR-509-5p on the expression and regulation of TRAF6 and other genes related to the NF-κB signaling pathway. The result confirmed that TRAF6 was a target gene of miR-509-5p. Compared with miR-509-5p-NC group, the luciferase activity of miR-509-5p group was significantly down-regulated (P < 0.01). Further, in sheep respiratory mucosal epithelial cells, miR-509-5p mimic could significantly down-regulate the fold change value of TRAF6 (P < 0.01). On the contrary, miR-509-5p-inhibitor up-regulated the fold change value of TRAF6 (P < 0.05). Interestingly, the expression levels of other genes were different. Among them, miR-509-5p mimic significantly up-regulated TLR4 and IRAK4 (P < 0.05), significantly down-regulated TAK1 (P < 0.05) and NF-κB (P < 0.01). miR-509-5p-inhibitor significantly up-regulated NF-κB (P < 0.05) and TAK1 (P < 0.01). miR-509-5p targets TRAF6 to affect the expression of downstream genes, which negatively regulates the NF-κB pathway, thereby affecting the inflammatory response.

BSE can propagate in sheep co-infected or pre-infected with scrapie.

To understand the possible role of mixed-prion infections in disease presentation, the current study reports the co-infection of sheep with bovine spongiform encephalopathy (BSE) and scrapie. The bovine BSE agent was inoculated subcutaneously into sheep with ARQ/ARQ or VRQ/ARQ PRNP genotypes either at the same time as subcutaneous challenge with scrapie, or three months later. In addition, VRQ/VRQ sheep naturally infected with scrapie after being born into a scrapie-affected flock were challenged subcutaneously with BSE at eight or twenty one months-of-age. Sheep were analysed by incubation period/attack rate, and western blot of brain tissue determined the presence of BSE or scrapie-like PrPSc. Serial protein misfolding cyclic amplification (sPMCA) that can detect very low levels of BSE in the presence of an excess of scrapie agent was also applied to brain and lymphoreticular tissue. For VRQ/ARQ sheep challenged with mixed infections, scrapie-like incubation periods were produced, and no BSE agent was detected. However, whilst ARQ/ARQ sheep developed disease with BSE-like incubation periods, some animals had a dominant scrapie western blot phenotype in brain, but BSE was detected in these sheep by sPMCA. In addition, VRQ/VRQ animals challenged with BSE after natural exposure to scrapie had scrapie-like incubation periods and dominant scrapie PrPSc in brain, but one sheep had BSE detectable by sPMCA in the brain. Overall, the study demonstrates for the first time that for scrapie/BSE mixed infections, VRQ/ARQ sheep with experimental scrapie did not propagate BSE but VRQ/VRQ sheep with natural scrapie could propagate low levels of BSE, and whilst BSE readily propagated in ARQ/ARQ sheep it was not always the dominant PrPSc strain in brain tissue. Indeed, for several animals, a dominant scrapie biochemical phenotype in brain did not preclude the presence of BSE prion.

Real-time monitoring of ruminal microbiota reveals their roles in dairy goats during subacute ruminal acidosis.

Ruminal microbiota changes frequently with high grain diets and the occurrence of subacute ruminal acidosis (SARA). A grain-induced goat model of SARA, with durations of a significant decrease in the rumen pH value to less than 5.6 and an increase in the rumen lipopolysaccharides concentration, is constructed for real-time monitoring of bacteria alteration. Using 16 S rRNA gene sequencing, significant bacterial differences between goats from the SARA and healthy groups are identified at every hour for six continuous hours after feeding. Moreover, 29 common differential genera between two groups over 6 h after feeding are all related to the altered pH and lipopolysaccharides. Transplanting the microbiota from donor goats with SARA could induce colonic inflammation in antibiotic-pretreated mice. Overall, significant differences in the bacterial community and rumen fermentation pattern between the healthy and SARA dairy goats are real-time monitored, and then tested using ruminal microbe transplantation to antibiotic-treated mice.

Fasciola gigantica-Derived Excretory-Secretory Products Alter the Expression of mRNAs, miRNAs, lncRNAs, and circRNAs Involved in the Immune Response and Metabolism in Goat Peripheral Blood Mononuclear Cells.

Fasciola gigantica produces excretory-secretory products (ESPs) with immune-modulating effects to promote its own survival. In this study, we performed RNA-seq to gain a comprehensive global understanding of changes in the expression of mRNAs, miRNAs, lncRNAs, and circRNAs in goat peripheral blood mononuclear cells (PBMCs) treated with F. gigantica ESPs. A total of 1,544 differently expressed mRNAs (790 upregulated and 754 downregulated genes), 30 differently expressed miRNAs (24 upregulated and 6 downregulated genes), 136 differently expressed circRNAs (83 upregulated and 53 downregulated genes), and 1,194 differently expressed lncRNAs (215 upregulated and 979 downregulated genes) were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed that F. gigantica ESPs altered the expression of genes associated with the host immune response, receptor signaling, disease and metabolism. Results from RNA-seq were validated by qRT-PCR. These findings provide an important resource for future investigation of the role of mRNAs and non-coding RNAs in mediating the immune-modulating effects of F. gigantica ESPs.

Brucella ovis Cysteine Biosynthesis Contributes to Peroxide Stress Survival and Fitness in the Intracellular Niche.

Brucella ovis is an ovine intracellular pathogen with tropism for the male genital tract. To establish and maintain infection, B. ovis must survive stressful conditions inside host cells, including low pH, nutrient limitation, and reactive oxygen species. The same conditions are often encountered in axenic cultures during stationary phase. Studies of stationary phase may thus inform our understanding of Brucella infection biology, yet the genes and pathways that are important in Brucella stationary-phase physiology remain poorly defined. We measured fitness of a barcoded pool of B. ovis Tn-himar mutants as a function of growth phase and identified cysE as a determinant of fitness in stationary phase. CysE catalyzes the first step in cysteine biosynthesis from serine, and we provide genetic evidence that two related enzymes, CysK1 and CysK2, function redundantly to catalyze cysteine synthesis at steps downstream of CysE. Deleting cysE (ΔcysE) or both cysK1 and cysK2 (ΔcysK1 ΔcysK2) results in premature entry into stationary phase, reduced culture yield, and sensitivity to exogenous hydrogen peroxide. These phenotypes can be chemically complemented by cysteine or glutathione. ΔcysE and ΔcysK1 ΔcysK2 strains have no defect in host cell entry in vitro but have significantly diminished intracellular fitness between 2 and 24 h postinfection. Our study has uncovered unexpected redundancy at the CysK step of cysteine biosynthesis in B. ovis and demonstrates that cysteine anabolism is a determinant of peroxide stress survival and fitness in the intracellular niche.

Compound heterozygous PLA2G6 loss-of-function variants in Swaledale sheep with neuroaxonal dystrophy.

Sporadic occurrences of neurodegenerative disorders including neuroaxonal dystrophy (NAD) have been previously reported in sheep. However, so far no causative genetic variant has been found for ovine NAD. The aim of this study was to characterize the phenotype and the genetic aetiology of an early-onset neurodegenerative disorder observed in several lambs of purebred Swaledale sheep, a native English breed. Affected lambs showed progressive ataxia and stiff gait and subsequent histopathological analysis revealed the widespread presence of axonal spheroid indicating neuronal degeneration. Thus, the observed clinical phenotype could be explained by a novel form of NAD. After SNP genotyping and subsequent linkage mapping within a paternal half-sib pedigree with a total of five NAD-affected lambs, we identified two loss-of-function variants by whole-genome sequencing in the ovine PLA2G6 gene situated in a NAD-linked genome region on chromosome 3. All cases were carriers of a compound heterozygous splice site variant in intron 2 and a nonsense variant in exon 8. Herein we present evidence for the occurrence of a familial novel form of recessively inherited NAD in sheep due to allelic heterogeneity at PLA2G6. This study reports two pathogenic variants in PLA2G6 causing a novel form of NAD in Swaledale sheep which enables selection against this fatal disorder.

Phage display-based vaccine with cathepsin L and excretory-secretory products mimotopes of Fasciola hepatica induces protective cellular and humoral immune responses in sheep.

Fasciolosis is a foodborne zoonotic disease that affects grazing animals and causes substantial economic losses worldwide. Excretory/secretory (E/S) products and cathepsin L mimotopes from Fasciola hepatica were used to immunise experimentally infected sheep against liver flukes. The level of protection was measured in terms of fluke burden, morphometric measurements and faecal egg counts, as well as the humoral and cellular immune responses elicited. Five groups of 5 sheep each were immunised with 1 × 1013 phage particles of cathepsin L1 (group 1: SGTFLFS), cathepsin L1 (group 2: WHVPRTWWVLPP) and immunodominant E/S product (group 3) mimotopes with Quil A adjuvant, and wild-type M13KE phage (group 4) at the beginning and as a booster two weeks later. The control group received phosphate-buff ;ered saline. All groups were challenged with 300 metacercariae at week four and slaughtered 18 weeks later. The mean fluke burdens after challenge were reduced by 52.39 % and 67.17 % in sheep vaccinated with E/S products (group 3) and cathepsin L1 (group 1: SGTFLFS), respectively; no eff ;ect was observed in animals inoculated with cathepsin L1 (group 2: WHVPRTWWVLPP). Animals vaccinated showed a significant reduction in fluke length and width, wet weights and egg output Sheep immunised with phage-displayed mimotopes induced the development of specific IgG1 and IgG2, indicating a mixed Th1/Th2 immune response. Measurement of cytokine levels revealed higher levels of IFN-γ as well as lower production of IL-4 in sheep vaccinated with the mimotope peptide of F. hepatica. Fluke-specific production of IFN-γ in immunised animals was significantly correlated with fluke burden (P < 0.01). As helminth infection progressed, increased levels of IL-4 were evident in the wild-type M13KE phage (group 4) and the control groups (group 5), accompanied by a downregulation of IFN-γ production. Vaccinated animals with cathepsin L1 (group 1: SGTFLFS) showed that amino acids located in the middle (64SG65) of the linear sequence and C-terminal end (314TFLFS318) were associated with significant protection.

Dynamics and within-host interaction of Theileria lestoquardi and T. ovis among naive sheep in Oman.

Mixed species infections of Theileria spp. are common in nature. Experimental and epidemiological data suggest that mixed species infections elicit cross-immunity that can modulate pathogenicity and disease burden at the population level. The present study examined within-host interactions, over a period of 13 months during natural infections with two Theileria spp., pathogenic (T. lestoquardi) and non-pathogenic (T. ovis), amongst a cohort of naive sheep in Oman. In the first two months after exposure to infection, a high rate of mortality was seen among sheep infected with T. lestoquardi alone. However, subsequently mixed-infections of T. lestoquardi and T. ovis prevailed, and no further death occurred. The overall densities of both parasite species were significantly higher as single infection vs mixed infection and the higher relative density of pathogenic T. lestoquardi indicated a competitive advantage over T. ovis in mixed infection. The density of both species fluctuated significantly over time, with no difference in density between the very hot (May to August) and warm season (September to April). A high degree of genotype multiplicity was seen among T. lestoquardi infections, which increased with rising parasite density. Our results illustrate a potential competitive interaction between the two ovine Theileria spp., and a substantial reduction in the risk of mortality in mixed parasite infections, indicating that T. ovis confers heterologous protection against lethal T. lestoquardi infection.

Neuropeptides in the urinary tract of male sheep lambs.

Small ruminants are often presumed to be at a higher risk of developing obstructive urolithiasis after early castration. However, the underlying pathophysiology and histological correlation of this assumption is unknown. This study examines the neuropeptide distribution of the lower urinary tract in male lambs in respect to castration status or a recent history of obstructive urolithiasis. Various tissue samples were taken and examined. The sample consisted of 34 male lambs, aged six months (n = 11 early and n = 11 late castration; n = 12 intact), and 8 rams that had undergone necropsy due to fatal outcome after obstructive urolithiasis. Immunohistochemical stainings for substance P (SP), vasoactive intestinal polypeptide (VIP) and neurofilaments (NF) were performed and compared between the groups. A significant reduction in immunoreactive signals of SP, VIP and NF was evident in the urolithiasis group (SP and NF: P < 0.0001; VIP: P = 0.02). The results of immunohistochemistry suggest that castration had no effect on the content of neuropeptides, as well as the innervation density of the urethra in the male lambs. In the case of. obstructive urolithiasis, the pattern of neuropeptide distribution was severely disturbed and cell damage lead to a reduction in detectable periurethral bundles of nerve fibers. The severe tissue damage was assumed to have a negative impact on the outcome of treatment, leading to complications such as urethral strictures. These, in turn, often result in relapses.

Pilot Evaluation of Two Fasciola hepatica Biomarkers for Supporting Triclabendazole (TCBZ) Efficacy Diagnostics.

Fasciola hepatica, the causative agent of fasciolosis, is a global threat to public health, animal welfare, agricultural productivity, and food security. In the ongoing absence of a commercial vaccine, independent emergences of anthelmintic-resistant parasite populations worldwide are threatening the sustainability of the few flukicides presently available, and particularly triclabendazole (TCBZ) as the drug of choice. Consequently, prognoses for future fasciolosis control and sustained TCBZ application necessitate improvements in diagnostic tools to identify anthelmintic efficacy. Previously, we have shown that proteomic fingerprinting of F. hepatica excretory/secretory (ES) products offered new biomarkers associated with in vitro TCBZ-sulfoxide (SO) recovery or death. In the current paper, two of these biomarkers (calreticulin (CRT) and triose phosphate isomerase (TPI)) were recombinantly expressed and evaluated to measure TCBZ efficacy via a novel approach to decipher fluke molecular phenotypes independently of molecular parasite resistance mechanism(s), which are still not fully characterised or understood. Our findings confirmed the immunoreactivity and diagnostic potential of the present target antigens by sera from TCBZ-susceptible (TCBZ-S) and TCBZ-resistant (TCBZ-R) F. hepatica experimentally infected sheep.

Suppression of hyaluronidase reduces invasion and establishment of Haemonchus contortus larvae in sheep.

Haemonchus contortus is a hematophagous endoparasite of small ruminants, which is responsible for huge economic losses in livestock sector. Hyaluronidase produced by infective larvae of H. contortus can degrade hyaluronic acid present in the host's abomasal tissue. Thus, it facilitates larval tissue invasion and early establishment. We herein explored this ability of hyaluronidase in H. contortus, and tested whether hyaluronidase is utilized as a virulence factor by H. contortus while establishing the infection. We first successfully blocked the hyaluronidase gene in L3 larvae by RNA interference (RNAi), which was subsequently confirmed by qPCR, enzymatic activity, and immunohistochemistry assays. Using these larvae we then conducted in vivo and in vitro assays on sheep to assess the effects of hyaluronidase suppression on larval invasion and establishment of infection. The in vivo assay showed a significant drop in worm burden in siRNA treated group in comparison to control group. During in vitro assay we applied an ovine ex vivo model where siRNA treated group of larvae showed significantly reduced invasion of the abomasal tissue explants as compared to control group. These findings indicate that hyaluronidase plays a key role in host's tissue invasion and larval establishment, and it is used as a virulence factor by H. contortus while establishing the infection. As an invasive virulence molecule, its functional research is thus conducive to the prevention of haemonchosis.

Comprehensive RNA-Seq profiling of the lung transcriptome of Bashbay sheep in response to experimental Mycoplasma ovipneumoniae infection.

The Bashbay sheep (Ovis aries), an indigenous breed of Xinjiang, China, has many excellent characteristics. It is resistant to Mycoplasma ovipneumoniae infection, the causative agent of mycoplasma ovipneumonia, a chronic respiratory disease that is harmful to the sheep industry. To date, knowledge regarding the mechanisms responsible for M. ovipneumoniae pathogenesis in scant. Herein, we report the results of transcriptome profiling of lung tissues from Bashbay sheep experimentally infected with an M. ovipneumoniae strain at 4 and 14 days post-infection, in comparison to mock-infected animals (0 d). Transcriptome profiling was performed by deep RNA sequencing, using the Illumina platform. The analysis of differentially expressed genes was performed to determine concomitant gene-specific temporal patterns of mRNA expression in the lungs after M. ovipneumoniae infection. We found 1048 differentially expressed genes (575 up-regulated, 473 down-regulated) when comparing transcriptomic data at 4 and 0 days post-infection, and 2823 (1362 up-regulated, 1461 down-regulated) when comparing 14 versus 0 days post-infection. Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the differentially expressed genes at 4 and 14 versus 0 days post-infection were enriched in 245 and 287 pathways, respectively, and the Toll-like receptor (TLR) signaling pathway was considered most closely related to MO infection (p < 0.01). Two pathways (LAMP-TLR2/TLR6-MyD88-MKK6-AP1-IL1B and LAMP-TLR8MyD88-IRF5-RANTES) were identified based on the TLR signaling pathway from differentially expressed genes related M. ovipneumoniae infection. Gene Ontology analysis showed that differentially expressed genes in different groups were enriched for 1580 and 4561 terms, where those most closely related to M. ovipneumoniae infection are positive regulators of inflammatory responses (p < 0.01). These results could aid in understanding how M. ovipneumoniae infection progresses in the lungs and may provide useful information regarding key regulatory pathways.

Refeeding syndrome in small ruminants receiving parenteral nutrition.

BACKGROUND: Small ruminants presented to tertiary care facilities commonly suffer from severe protein-calorie malnutrition. Some of these patients require parenteral nutrition (PN; amino acids and dextrose with or without lipids) during hospitalization. Refeeding syndrome, a potentially fatal shift of electrolytes seen in malnourished patients during refeeding, may occur. OBJECTIVE: (a) To report the prevalence of refeeding syndrome in small ruminants receiving PN and (b) to determine risk factors for the development of refeeding syndrome. ANIMALS: Hospitalized small ruminants (n = 20) that received PN from 2010 to 2018 and that had serial (≥2) monitoring of serum electrolyte concentrations after initiation of PN. METHODS: Retrospective case series. Refeeding syndrome was defined as the presence of at least 2 of the following electrolyte abnormalities after initiation of PN: hypophosphatemia, hypokalemia, hypomagnesemia, or some combination of these. Data was analyzed using Fisher's exact test, followed by univariate logistic regression. RESULTS: Eleven of 20 (55%) animals met the definition of refeeding syndrome. Mean minimum serum phosphorus concentration in animals with refeeding syndrome was 1.96 ± 0.69 mg/dL (reference range, 4.2-7.6 mg/dL). Eleven of 20 animals survived to discharge. Survival rate did not differ significantly between refeeding cases (4/11, 36.3%) and nonrefeeding cases (7/9, 77.8%; P = .09). Mean serum phosphorus concentration was significantly lower in nonsurvivors than in survivors (1.88 ± 0.10 mg/dL vs 4.32 ± 0.70 mg/dL, P = .006). CONCLUSIONS AND CLINICAL IMPORTANCE: We report the prevalence of refeeding syndrome in small ruminants receiving PN. Clinicians should anticipate refeeding syndrome after initiation of PN and consider pre-emptive supplementation with phosphorus, potassium, magnesium, or some combination of these.

Ruminal fermentation, microbial population and lipid metabolism in gastrointestinal nematode-infected lambs fed a diet supplemented with herbal mixtures.

The aim of this study was to evaluate the effects of medicinal herbal mixtures rich in phenolic, flavonoid and alkaloid compounds on ruminal fermentation and microbial populations, and fatty acid (FA) concentrations and lipid oxidation in tissues of lambs infected with the gastrointestinal nematode (GIN) parasite (Haemonchus contortus). Parallel in vitro and in vivo studies were performed using two different herbal mixtures (Mix1 and Mix2). The in vitro study was conducted in a 2 (infection status; non-infected versus infected) × 3 (diets; control, Mix1 and Mix2) factorial design. In the in vivo study, 24 lambs were equally divided into four treatments: non-infected lambs fed a control diet, infected lambs fed the control diet, infected lambs fed a diet with Mix1 and infected lambs fed a diet with Mix2. Herbal mixtures (100 g dry matter (DM)/d) were added to the basal diets of meadow hay (ad libitum) and a commercial concentrate (500 g DM/d). The experimental period lasted for 70 days. Ruminal fermentation characteristics and methane production were not affected by infection in vivo or in vitro. Both herbal mixture supplementation increased total volatile fatty acid (VFA) concentrations (P < 0.01) and DM digestibility (P < 0.01) in vitro. Archaea population was slightly diminished by both herbal mixtures (P < 0.05), but they did not lower methane production in vitro or in vivo (P > 0.05). Infection of H. contortus or herbal mixtures modulated FA proportion mainly in the liver, especially the long chain FA proportion. Concentrations of thiobarbituric acid reactive substances (TBARS) in serum were significantly higher after 70 days post-infection in the infected lambs. Herbal Mix1 supplementation reduced TBARS concentrations in meat after seven days of storage. In conclusion, supplementing of herbal mixtures to the diets of GIN parasite infected lambs did not affect the basic ruminal fermentation parameters. Herbal mixtures may improve few FA proportions mainly in liver as well as decrease lipid oxidation in meat.

Studies of Selenium Deficiency in the Wumeng Semi-Fine Wool Sheep.

Wumeng semi-fine wool sheep are affected by a disease, characterized by emaciation, stiffness and trembling of the limbs, weakness and inability to stand, and sudden death. The objective of the study was to determine possible relationships between the disease and mineral deficiencies. Samples of wool, blood, and liver were collected from affected and healthy sheep. Samples of soil and forage were collected from affected and unaffected areas. The samples were used for hematological and biochemical analyses and mineral nutrient measurements. Results showed that selenium concentrations in forage and soil samples from affected areas were significantly lower than those from unaffected areas (P < 0.01). Meanwhile, selenium concentrations of wool, blood, and liver from the affected sheep were also significantly lower than those from the healthy sheep (P < 0.01). The mean concentration of hemoglobin (Hb), packed cell volume (PCV), and mean corpuscular hemoglobin (MCH) from the affected sheep were significantly lower than those from the healthy sheep (P < 0.01). Serum glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activity in the affected sheep were significantly lower than those in the healthy sheep (P < 0.01). Serum creatine phosphokinase (CPK), lactate dehydrogenase (LDH), glutamate pyruvate transaminase (GPT), glutamic oxaloacetic transaminase (GOT), alkaline phosphatase (ALP), and malondialdehyde (MDA) values in the affected sheep were significantly higher than those in the healthy sheep (P < 0.01). Serum concentrations of free triiodothyronine (FT3) and triiodothyronine (TT3) in the affected sheep were significantly lower than those in the healthy sheep; serum concentrations of free tetraiodothyronine (FT4) and tetraiodothyronine (TT4) in the affected sheep were significantly higher than those in the healthy sheep (P < 0.01). But the administration of selenium and vitamin E by hypodermic injection prevented and cured the disease. The injection contains 0.1% and 5% of sodium selenite and vitamin E, respectively. A single dose is 6, 6, and 2 mL for mature ewe, mature ram, and lamb, respectively, repeated only once 15 days later. This study demonstrated that the disorder of Wumeng semi-fine wool sheep was mainly caused by the selenium deficiency in soil and forage.

N-carbamylglutamate and l-arginine promote intestinal function in suckling lambs with intrauterine growth restriction by regulating antioxidant capacity via a nitric oxide-dependent pathway.

Data indicate that intrauterine growth restriction (IUGR) in newborns can be partly alleviated through the supply of l-arginine (Arg) and N-carbamylglutamate (NCG). The current work aimed to explore whether Arg and NCG promote intestinal function by regulating antioxidant capacity in suckling lambs with IUGR via a nitric oxide (NO)-dependent pathway. Forty eight newly born Hu lambs with normal weights at birth (CON) or suffering from IUGR were randomly divided into 4 groups (n = 12 per group), namely, the CON, IUGR, IUGR + 1% Arg, and IUGR + 0.1% NCG groups. The animals were used for experiments from the age of day 7 to 28. Compared with the lambs in the IUGR group, the lambs in the Arg or NCG group had higher (P < 0.05) final body weights. The plasma insulin, NO, and NO synthase (NOS) concentrations in the IUGR group were higher (P < 0.05) compared with those in IUGR + 1% Arg or IUGR + 0.1% NCG. The jejunal level of the tumor necrosis factor α (TNF-α) in the IUGR lambs was greater (P < 0.05) compared with that in IUGR + 1% Arg or IUGR + 0.1% NCG. The plasma and jejunal total antioxidant capacity (T-AOC) values for the IUGR + 1% Arg or IUGR + 0.1% NCG group were greater (P < 0.05) compared with those for the IUGR group. Compared with the IUGR + 1% Arg or IUGR + 0.1% NCG lambs, the IUGR lambs had lower (P < 0.05) abundance of mRNA and protein abundance of glutathione peroxidase 1 (GPx1), catalase (CAT), superoxide dismutase 2 (SOD2), nuclear factor erythroid 2-related factor 2 (Nrf2), quinone oxidoreductase 1 (NQO1), heme oxygenase (HO-1), zonula occludens-1 (ZO-1), occludin, inducible NOS (iNOS), and epithelial NOS (eNOS). Overall, the data suggest that the Arg or NCG supplementation to suckling lambs with IUGR enhances the intestinal function by regulating the oxidant status via the NO-dependent pathway.