Sheep Faeces Research Articles

Determination of Subtypes, Serogroups, And Serotypes, Virulence, and/or Toxigenic Properties of Escherichia coli Isolated From Cattle, Sheep, and Goat Feces by Multiplex PCR

Determination of Subtypes, Serogroups, And Serotypes, Virulence, and/or Toxigenic Properties of Escherichia coli Isolated From Cattle, Sheep, and Goat Feces by Multiplex PCR

Combination Therapy of Guajava Leaf Powder (Psidium Guajava L) and Turmeric Powder (Curcuma Domestica Val) to Cure Diarrhea in Sheep

This study aims to determine the therapeutic effect of guava leaf powder and turmeric powder on the healing of diarrhea in sheep. This study used a completely randomized design (CRD) with four treatments, each consisting of three repetitions. P0 treatment as a control in three sheep and nine sheep for P1, P2, and P3 treatments with different doses (400 mg/kg BW, 500 mg/kg BW, 600 mg/kg BW). Parameters assessed were frequency of defecation, consistency, and color of sheep feces. The combined treatment of guava leaf powder and turmeric powder on sheep diarrhea was analyzed using ANOVA statistical analysis and Duncan's further test after scoring changes in healing. The result of the ANOVA analysis was a significant difference of 0.007 (P<0.01) on Day 3 compared to Day 1 and Day 2. Duncan's further test was that P0 was not significantly different from P1 but significantly different from P2 and P3. P1 was not significantly different from P0 and P2 but significantly different from P3. P2 was significantly different from P0 but not significantly different from P1 and P3, while P3 with P0 and P1 showed significantly different but not significantly different from P2.

Using Arthrobotrys oligospora (Orbiliales) spores mixed with sterile sheep faeces for disinfesting soil micro-plots infested with Nacobbus aberrans (Nematoda: Pratylenchidae)

ABSTRACT This study explored the initial step to develop of a potential biopesticide for controlling Nacobbus aberrans (J2) using spores of the nematophagous fungus Arthrobotrys oligospora (Ao) mixed with sterile sheep faeces. One strain of Ao (50–80) of the National Centre of Disciplinary Research in Animal Health and Innocuity (INIFAP) collection was used. The assay was performed using plastic glasses. Three experimental groups were established as follows: (1) negative Control (only N. aberrans J2) (without fungi); (2) positive control (pesticide), with 5 mL (0.131 g) of Cabofuran (®Furadan 350 L) per glass; (3) fungus Ao, 300,000 spores as a total amount. Treatment with Ao spores reduced the N. aberrans (J2) population by 94.7%, whereas the pesticide, reduced the population by 94.5% in relation to the control group (P ≤ 0.05). A mixture of sterile sheep faeces containing Ao spores reduces the population of N. aberrans, a pathogenic nematode affecting the health and production of economically important crops.

Complete genome analysis of Bacillus velezensis TS5 and its potential as a probiotic strain in mice.

In recent years, a large number of studies have shown that Bacillus velezensis has the potential as an animal feed additive, and its potential probiotic properties have been gradually explored. In this study, Illumina NovaSeq PE150 and Oxford Nanopore ONT sequencing platforms were used to sequence the genome of Bacillus velezensis TS5, a fiber-degrading strain isolated from Tibetan sheep. To further investigate the potential of B. velezensis TS5 as a probiotic strain, in vivo experiments were conducted using 40 five-week-old male specific pathogen-free C57BL/6J mice. The mice were randomly divided into four groups: high fiber diet control group (H group), high fiber diet probiotics group (HT group), low fiber diet control group (L group), and low fiber diet probiotics group (LT group). The H and HT groups were fed high-fiber diet (30%), while the L and LT groups were fed low-fiber diet (5%). The total bacteria amount in the vegetative forms of B. velezensis TS5 per mouse in the HT and LT groups was 1 × 109 CFU per day, mice in the H and L groups were given the same volume of sterile physiological saline daily by gavage, and the experiment period lasted for 8 weeks. The complete genome sequencing results of B. velezensis TS5 showed that it contained 3,929,788 nucleotides with a GC content of 46.50%. The strain encoded 3,873 genes that partially related to stress resistance, adhesion, and antioxidants, as well as the production of secondary metabolites, digestive enzymes, and other beneficial nutrients. The genes of this bacterium were mainly involved in carbohydrate metabolism, amino acid metabolism, vitamin and cofactor metabolism, biological process, and molecular function, as revealed by KEGG and GO databases. The results of mouse tests showed that B. velezensis TS5 could improve intestinal digestive enzyme activity, liver antioxidant capacity, small intestine morphology, and cecum microbiota structure in mice. These findings confirmed the probiotic effects of B. velezensis TS5 isolated from Tibetan sheep feces and provided the theoretical basis for the clinical application and development of new feed additives.

Multiple clonal transmissions of clinically relevant extended-spectrum beta-lactamase–producing Escherichia coli among livestock, dogs, and wildlife in Chile

Extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-E. coli) are a main cause of human deaths associated with antimicrobial resistance (AMR). Despite hundreds of reports of the faecal carriage of ESBL-E. coli in domestic and wild animals, the dynamics of its circulation remains poorly understood. We used whole genome sequencing of 19 ESBL-E. coli previously isolated in the same local setting from dogs, livestock, and a wild rodent in Central Chile to assess potential cross-species transmission of ESBL-E. coli. Isolates harboured a large number of AMR (n=95) and virulence (n=45) genes, plasmids replicons (n=24) and E. coli Sequence Types including top extraintestinal pathogenic E. coli ST410, ST58, ST88, and ST617. Almost identical clones (<50 SNPs difference, same antibiotic and heavy metal resistance genes, virulence genes, and plasmids) were found in faeces of dogs, cattle or sheep from the same farm, and in a dog and a wild rodent living in proximity. To our knowledge, this is the first report of multiple clonal cross-species transmission of ESBL-E. coli in domestic and potentially wild animals of Latin America. Our results suggest that relatively rare spread of AMR across animal species can still occur by both clonal and plasmid dissemination. Our study highlights the need for establishing preventive measures to limit the circulation of these bacteria among animals in agricultural settings, particularly given the highly pathogenic profile of several E. coli strains detected in these animals.

An initial investigation of the predatory activity of the phoretic mites of dung beetles, Macrocheles sp. (Mesostigmata: Macrochelidae), on the gastrointestinal nematode of sheep Haemonchus contortus (Strongylida: Trichostrongylidae)

Worldwide increasing levels of anthelmintic resistance are pushing farmers and health advisors towards a more sustainable management of gastrointestinal nematodes (GIN), one of the greatest threats to the viability of grazing small ruminant production systems, and to these animals’ welfare. These Strongyloidea develop freely in livestock dung, where they are exposed to predatory organisms that can eventually break their cycle. The aim of this study was to investigate the effect of phoretic mites of dung beetles Macrocheles sp. (Macrochelidae) on the gastrointestinal nematode Haemonchus contortus (Rudolphi, 1803) that has a free-living larval stage that evolves in sheep feces. Direct observations under a stereomicroscope confirmed that the studied Macrocheles mites may have an active predatory behavior on the third-stage (L3) larvae of H. contortus. In order to quantify the effects of the mites’ predation on the survival of L3 nematode larvae, we designed experimental units, replicated across five trials, and containing free-living stages of the nematode either in the presence or absence of mites. The number of H. contortus larvae that reached the third-stage was significantly reduced in the presence of mites, despite a variable intensity of the predatory effects between trials. This is the first report of a predatory activity of phoretic mites of dung beetles’ on a livestock gastrointestinal nematode. This first step encourages further studies in order to have a better quantification of this interaction, and to investigate to which extent the phoretic mites of dung beetles can impact H. contortus populations in natural conditions.

Effect of Levels of Organic Matter on Adsorption and Liberation of Gypsum Soil

In an experiment for iron adsorption for nine levels of iron (0,1,2,5,10,25,50,100,200)mg/L. This experiment was carried out to find the behaviour of iron in soils of varying gypsum and organic content to know the conditions for adsorption and liberation of iron in them, using three gypsums (10,20,30)% with percentages of organic matter from sheep feces (0,1,2)%. The Langmeyer equation, the Feinrendlach equation, and the Timken equation were used, through which the most excellent adsorption and binding energy were calculated. The most outstanding adsorption values were In medium gypsum soil with sheep feces (2%) with a ratio in the Langmeyer equation (46.948) mg/kg. The highest binding energy value was (7.497) L.mg-1 in soils with low gypsum content as a control. Lanckmeyer equation was chosen as the best It is fair to describe the adsorption process with a capacity determination coefficient of (85)%. In comparison, the highest value for the maximum adsorption of the Freindlch equation was recorded (0.788) litre.mg-1 in soils with high gypsum content with sheep feces by (2%). The highest percentage of binding energy in medium soils, gypsum control, was (16.195) mg.kg-1. The highest binding energy value in the Tamken equation was (12.436) mg.kg-1 in medium gypsum control soil. The highest binding energy value was (2.844) L.kg-1 in medium gypsum soil control. As for the liberation experiment, the highest values for liberated iron were in the high levels of addition (18.513) mg.kg-1 in soils with low gypsum content (2)% of sheep feces, noting the low values Released iron with low values of adsorbed iron.

Screening of probiotic strains of Lactiplantibacillus plantarum from Hu sheep and its ability to inhibit Listeria monocytogenes in pasteurized milk

Hu sheep is an important sheep breed in China whose intestines are rich in probiotics. In this study, a total of fifty-nine lactic acid bacteria strains were isolated from Hu sheep feces and twelve strains were identified as Lactiplantibacillus plantarum. Among them, six L. plantarum strains were selected and further evaluated for their probiotic properties. Our results suggested that L. plantarum ELPL14 possess potential probiotic properties. The application of ELPL14 against L. monocytogenes in the pasteurized milk was investigated and the results showed that the growth of L. monocytogenes was significantly decreased when simultaneously incubated with ELPL14 in pasteurized milk at 37 °C. Meanwhile, in the ELPL14 fermented pasteurized milk, the growth of L. monocytogenes was also significantly decreased at 28 °C and 4 °C. We further tested the plantaricin genes by PCR, and found that eleven plantaricin genes (plnEF, plnR, plnJ, plnK, plnL, plnN, plnB, plnC, plnD, plnI, and plnH) were detected in the genome of ELPL14, suggesting that the inhibition of ELPL14 against L. monocytogenes might be due to the production of bacteriocin. Our results demonstrated that L. plantarum ELPL14 from Hu sheep has the potential as a natural candidate for dairy additives to inhibit food-borne pathogens, especially L. monocytogenes.

Isolation and Genomic Characteristics of Cat-Borne Campylobacter felis sp. nov. and Sheep-Borne Campylobacter ovis sp. nov.

Nine novel bacterial strains were isolated from the feces of cats and sheep in 2019 and 2020 in Beijing, China. Cells were 1-3 μm long and ≤0.5 μm wide, Gram-stain negative, microaerobic, motile, oxidase positive, and urease negative. Phylogenetic analyses based on 16S rRNA gene sequences indicated that these nine isolates belong to the genus Campylobacter but formed two robust clades that were clearly separate from the currently recognized species and, respectively, isolated from the cat and sheep. Both these strains shared low 16S rRNA gene sequence similarity, dDDH relatedness, and ANI values with their closest species C. upsaliensis CCUG 14913T and C. lanienae NCTC 13004T, and against each other, which are below the cut-off values generally recognized for isolates of the same species. The genomic DNA G + C contents of type strains XJK22-1T and SYS25-1T were 34.99 mol% and 32.43 mol%, respectively. Electron microscopy showed that these cells were spiral shaped, with bipolar single flagella. Based on results from genotypic, phenotypic, phylogenetic, and phylogenomic analyses, these nine strains represent two novel species within the genus Campylobacter, for which the names Campylobacter felis sp. nov. (Type strain XJK22-1T = GDMCC 1.3684T = JCM 35847T) and Campylobacter ovis sp. nov. (Type strain SYS25-1T = GDMCC 1.3685T) are proposed.

Facial Preparation of Cyclometalated Iridium (III) Nanowires as Highly Efficient Electrochemiluminescence Luminophores for Biosensing.

In this study, highly efficient ECL luminophores composed of iridium complex-based nanowires (Ir-NCDs) were synthesized via covalently linking bis(2-phenylpyridine)-(4-carboxypropyl-2,2'-bipyridyl) iridium(III) hexafluorophosphate with nitrogen-doped carbon quantum dots (NCDs). The ECL intensity of the nanowires showed a five-fold increase in ECL intensity compared with the iridium complex monomer under the same experimental conditions. A label-free ECL biosensing platform based on Ir-NCDs was established for Salmonella enteritidis (SE) detection. The ECL signal was quenched linearly in the range of 102-108 CFU/mL for SE with a detection limit of 102 CFU/mL. Moreover, the relative standard deviations (RSD) of the stability within and between batches were 0.98% and 3.9%, respectively. In addition, the proposed sensor showed high sensitivity, selectivity and stability towards SE in sheep feces samples with satisfactory results. In summary, the excellent ECL efficiency of Ir-NCDs demonstrates the prospects for Ir(III) complexes in bioanalytical applications.

In vitro study: Soybean meal substitution with maggot on sheep digestibility and rumen fermentation

The in vitro study aimed to evaluate the utilization of maggot flour from selected substrates as a substitute for soybean meal in sheep rations on digestibility and rumen fermentation in vitro. Maggot were reared using three different substrates i.e., sheep feces, household waste and bread waste. The BSF maggot product with feces substrate showed the highest protein was used in this study. The treatments in this study were T1=100% soybean meal, T2=50% soybean meal + 50% maggot flour, T3=100% maggot flour. In vitro rumen fermentation and digestibility were conducted and the parameters were pH, NH3, volatile fatty acid (VFA), dry matter digestibility (DMD) and organic matter digestibility (OMD). Maggot rearing data were presented descriptively while the in vitro data were analyzed using analysis of variance. The result showed that the treatments had no significant effect (P&gt;0.05) on pH, VFA, DMD and OMD, but replacement of soybean meal (100% maggot flour) affected NH3 production. The utilization of maggot as a substitute for soybean meal in sheep ration did not have a negative impact on in vitro fermentability and rumen digestibility.

Enterobacterales plasmid sharing amongst human bloodstream infections, livestock, wastewater, and waterway niches in Oxfordshire, UK.

Plasmids enable the dissemination of antimicrobial resistance (AMR) in common Enterobacterales pathogens, representing a major public health challenge. However, the extent of plasmid sharing and evolution between Enterobacterales causing human infections and other niches remains unclear, including the emergence of resistance plasmids. Dense, unselected sampling is essential to developing our understanding of plasmid epidemiology and designing appropriate interventions to limit the emergence and dissemination of plasmid-associated AMR. We established a geographically and temporally restricted collection of human bloodstream infection (BSI)-associated, livestock-associated (cattle, pig, poultry, and sheep faeces, farm soils) and wastewater treatment work (WwTW)-associated (influent, effluent, waterways upstream/downstream of effluent outlets) Enterobacterales. Isolates were collected between 2008 and 2020 from sites <60 km apart in Oxfordshire, UK. Pangenome analysis of plasmid clusters revealed shared 'backbones', with phylogenies suggesting an intertwined ecology where well-conserved plasmid backbones carry diverse accessory functions, including AMR genes. Many plasmid 'backbones' were seen across species and niches, raising the possibility that plasmid movement between these followed by rapid accessory gene change could be relatively common. Overall, the signature of identical plasmid sharing is likely to be a highly transient one, implying that plasmid movement might be occurring at greater rates than previously estimated, raising a challenge for future genomic One Health studies.

Stability of SARS-CoV-2 in Biological Fluids of Animals.

Since its first emergence in 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has continued to evolve genetically, jump species barriers, and expand its host range. There is growing evidence of interspecies transmission including infection of domestic animals and widespread circulation in wildlife. However, knowledge of SARS-CoV-2 stability in animal biological fluids and their role in transmission is still limited as previous studies focused on human biological fluids. Therefore, this study aimed to determine the SARS-CoV-2 stability in biological fluids from three animal species, cats, sheep and white-tailed deer (WTD). Saliva, feces, 10% fecal suspensions, and urine of cats, sheep, and WTD were mixed with a known concentration of virus and incubated under indoor and three different climatic conditions. Our results show that the virus was stable for up to 1 day in the saliva of cats, sheep, and WTD regardless of the environmental conditions. The virus remained infectious for up to 6 days in feces and 15 days in fecal suspension of WTD, whereas the virus was rather unstable in cat and sheep feces and fecal suspensions. We found the longest survival of SARS-CoV-2 in the urine of cats, sheep, and WTD. Furthermore, side-by-side comparison with different SARS-CoV-2 strains showed that the Alpha, Delta, and Omicron variants of concern were less stable than the ancestral Wuhan-like strain in WTD fecal suspension. The results of our study provide valuable information for assessing the potential role of various animal biological fluids in SARS-CoV-2 transmission.

Isolation and identification of intestinal parasites from Goats in some areas of Wasit Province, Iraq

The current study was conducted on goats in various parts of Wasit Province, Iraq, from November 2021 to April 2022. The study aims to find and identify intestinal parasites (IPs) in goats in Wasit province. The goat's fresh fecal specimens (n=180) include cysts, eggs, oocysts, trophozoites and larval stages. One hundred eighty sheep feces samples were collected, and more than one parasite was isolated from one sample (mixed infection). According to the data acquired, the overall prevalence of intestinal parasites in goats was 52.77 (95 samples). In the current investigation, eleven distinct (IPs) species with infection rates were identified, including Toxocara vitulorum (Goeze, 1782) (16.66 %), Cryptosporidium sp.( Tyzzer, 1907) (11.11%), Amoeba sp. (8.8%), Giardia sp.( Künstler, 1882) (8.8%), Trichostrongylus sp.( Looss, 1905) (8.33%), Cyclospora sp. (Schneider, 1881) (5.55%), Dicrocoelium dendriticum synonym (Distoma dendriticum) (Rudolphi, 1819) (5%), Paramphistomum cervi (Zeder, 1790) (4.44%), cercaria larva (2.22%), Balantidium coli (Malmsten, 1857) (1.66%), filariae form larvae (1.66%), respectively. This may be the result of infection with various parasites due to the use of Conventional and unsanitary management systems Keywords: Intestinal Parasites, Goats, Toxocara vitulorum, Cryptosporidium spp.

The impact of feeding supplemental minerals to sheep on the return of micronutrients to pasture via urine and faeces

The form (organic versus inorganic) of minerals (Se, Zn, Cu and Mn), supplemented to sheep (Charolais × Suffolk-Mule (mean weight = 57 ± 2.9 kg) at two European industrial doses, on the return of micronutrients to pasture via nutrient partitioning and composition in sheep urine and faeces was investigated. This gave four treatments in total with 6 animals per treatment (n = 24). The form of the supplemented minerals did not influence the excretory partitioning of micronutrients (Se, Zn, Cu and Mn) between urine and faeces, nor on their concentrations in the excreta. The two doses trialed however, may influence the Se flux in the environment through altering the ratios of Se:P and Se:S ratios in the faeces and Se:S ratio in the urine. Administration of the mineral supplements also improved the retention of P in sheep reducing its excretion via urine. Although the concentrations of readily bioavailable micronutrients in the faeces were not affected by the mineral forms, there were differences in the more recalcitrant fractions of Se, Zn and Cu (as inferred via a sequential extraction) in faeces when different forms of supplemental minerals were offered. The potential impact of these differences on micronutrient flux in pasture requires further investigation.

Improved DNA Amplification of the Hallmark IS900 Element in Mycobacterium avium subsp. paratuberculosis: a Reexamination Based on Whole-Genome Sequence Analysis.

Amplification of the IS900 multicopy element is a hallmark nucleic acid-based diagnostic test for Mycobacterium avium subsp. paratuberculosis, which causes Johne's disease in ruminants. This assay is frequently used to determine the presence of the bacterium in feces of infected cattle and sheep. Two IS900 primer sets developed in the 1990s were widely used for decades, and their use has continued in current studies. However, these primers were developed prior to the availability of complete genome sequences. Recent sequence analysis of the binding locations for one primer pair (P90/P91) identified errors and binding inefficiencies that can be easily corrected to further increase detection sensitivity. The P90 primer is missing two nucleotides that should be present near the 3' end, and it does not bind all copies of IS900 due to 5' deletions at some IS900 loci. These IS900 primer pairs, along with newly developed primers, were tested by real-time PCR on purified genomic DNA to determine which primer set performed the best and how primer design errors affect amplification efficiencies. The newly designed PCR primer set (JB5) showed increased sensitivity by two to three quantification cycles using purified genomic DNA and was similar in efficiency to 150C/921. These tests were extended using DNA from feces and tissues of infected cows, which showed similar results. Finally, a 167-bp partial duplication of IS900 was found in type I strains. Although P90 and P91 primers successfully amplify M. avium subsp. paratuberculosis DNA, their use should be discontinued in favor of more efficient primer pairs in future studies. IMPORTANCE This study is an example of how applied genomic analysis can aid diagnostic test improvements. Detection of Mycobacterium avium subsp. paratuberculosis infection of livestock prior to the appearance of clinical disease signs is very difficult but essential for identifying animals shedding the bacterium to prevent transmission of Johne's disease. Total M. avium subsp. paratuberculosis quantity in the feces as determined by real-time PCR (qPCR) using the IS900 target indicates bacterial shedding status and potential for transmission of the pathogen. However, legacy primers designed prior to the availability of complete genome sequences that are used in these tests to detect M. avium subsp. paratuberculosis were based on data from only a single copy of IS900 and not considering all copies collectively as a group. This approach resulted in primer design errors which can be easily corrected to improve test sensitivities. We tested original primers that contain these errors and their corrected versions by qPCR and showed improved sensitivity on purified genomic DNA as well as fecal and tissue samples. These findings may help detect the organism from environmental samples on farms where sensitivity is currently lacking.

Antimicrobial resistance of Shiga toxin‐producing Escherichia coli isolated from sheep

The presence of Shiga toxin-producing Escherichia coli (STEC) and resistance to beta-lactams in healthy sheep represents a potential public health risk. This study aimed to characterize STEC isolates in sheep feces for toxin production and resistance to beta lactam antibiotics. In the present study, among the 40 isolates, we found a predominance of subtype Stx1 (22/40), followed by subtype Stx1 + Stx2 (11/40), while the less prevalent group was Stx2 (7/40). Also, we found phenotypical resistance to beta-lactam antibiotics in 50% (20/40) of the strains analyzed, forming two groups, one with resistant isolates and the other with non-resistant isolates. The cytotoxicity of the isolates did not vary among the groups. In addition to having this characteristic, some multiresistant isolates produced significant amounts of toxins. This leads to the conclusion that the mechanisms of antimicrobial resistance via beta lactamases are present in sheep STEC and that the cytotoxicity of those isolates is variable regarding such resistance.

Integrating microfossil records from livestock dung burned as fuel in Menorca, Balearic Islands

Interdisciplinary microarchaeological approaches including integrated studies of plant and faecal microfossils are fundamental to identify and interpret fuel remains within combustion installations such as hearths and ovens which are common across the Mediterranean. This is particularly critical in cases when other sources of archaeobotanical evidence such as charred macroremains are partially uninformative or absent, in order to assess the nature of burnt fuel, as similar plant records may derive from plant-based fuels and other fuel types including animal dung.The current research illustrates the contribution of integrated analytical methods in archaeobotany to interdisciplinary approaches on the identification, seasonality, and the impact of fuelling on modern livestock dung. The focus is on pollen, phytoliths, and calcitic dung spherulites embedded within cattle, sheep and pig faeces collected in different seasons of the year and farms from UNESCO Biosphere Reserve Menorca, Balearic Islands, Western Mediterranean. Experimental firing reference records provide modern comparative datasets on factors affecting the microfossil content and preservation of animal faeces used as a fuel source, as well as on the range of natural and anthropogenic pathways influencing these which are critical to identify and accurately interpret fuel remains. The results reported here are also compared to laboratory-controlled experimental datasets as well as ethnoarchaeological records including firing measurements (time and temperature) from cooking installations that have followed a similar integrated methodological approach.Experimental and ethnoarchaeological records provide fundamental information on taphonomic issues that are understudied, such as variation in the production and its integrity among different animal defecators, as well as on seasonality of plant and faecal microfossils that are embedded within the dung, and the impact of fire on these as a result of fuel use, as an important combustion material which is still commonly overlooked.

Survival, mobilization, and transport of Escherichia coli from sheep faeces.

This study looked at the survival, mobilization, and transport of Escherichia coli from sheep faeces over an extended period, which was then repeated for all four seasons. Rain simulation was used to measure E. coli mobilization directly from faecal pats and subsequent transport across a soil surface. The rain simulation experiments were conducted over the same 90-day period and for the four seasons as per the survival experiments conducted to determine E. coli survival in faecal pats. The survival experiments demonstrated up to three orders of magnitude increase of E. coli in sheep faeces. Peak E. coli concentrations in the faeces were observed on Day 2 through to Day 30, with no significant effect of seasons or weather patterns. The E. coli concentrations in the runoff followed the survival pattern of E. coli concentrations in the faeces. There was a statistically significant relationship between the E. coli concentrations in the faeces and the runoff. The data generated on the relationship between Escherichia coli concentrations in the faeces and in the runoff can support the development of runoff risk models for sheep grazing pastureland to support catchment modelling, land use decisions, and public health.

Measurement of fecal T3 metabolite levels in sheep: Analytical and biological validation of the method.

Biological sample collection from wild and farms animals is often associated with difficulties related to the handling and restraint procedures, and most of the time it could induce stress, altering the welfare and physiological homeostasis. The analysis of fecal T3 metabolites (FTMs) allows to test samples collected in a non-invasive manner, providing several information about the animal's physiological conditions and the effects related to environmental and nutritional variations. This procedure has found wide application in wild species, but less in domestic ones. The aim of this work was to validate the use of an immuno-enzymatic competitive ELISA kit, designed for T3 quantification in human blood serum samples, for the assessment of FTMs in the sheep. For the analytical validation, precision, recovery and parallelism were evaluated; for biological validation the variations of FTMs in relation to age, sex and the physiological status of the animal were determined. After a verification of the precision (RSD % < 15%), mean recovery (75%) and parallelism (CV% < 10%), the kit was used to measure FTMs in cyclic, pregnant, and early lactating ewes as well as in rams and ewe lambs. The results showed that FTMs concentrations in pregnant ewes were significantly lower (p < 0.05) than in cyclic and early lactation ones. Furthermore, there were no significant differences in FTMs levels between ewes and rams, while in lambs FTMs levels were higher than in adults (p < 0.001). In conclusion the present study demonstrates that FTMs can be reliably and accurately determined in sheep feces, using an ELISA kit formulated for human serum T3 assay. The application of this method in the livestock sector could allow to improve our knowledge about the response of animals to different physiological and environmental conditions, and thus assess their welfare.