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The number of people on our planet is projected to rise to between 9.4 and 10 billion by 2050. Some estimates suggest that current levels of food production will need to double to feed this population. Increasing the intensity of food production on existing agricultural land will be a crucial element in meeting this goal, but practices associated with intensive management can cause biodiversity declines and erode the ecosystem functions that underpin production. My work explores agricultural intensification within the context of pasture-based cattle production. I focus on a variety of ecosystem functions supported by dung beetles (Coleoptera: Scarabaeoidea) and other dung-associated invertebrates. I investigate how variations in diversity, and chemical perturbations of veterinary anthelmintics affect the delivery of multiple ecosystem functions. I show that maintaining species-rich dung beetle assemblages has inconsistent benefits in providing multiple ecosystem functions. While dung beetles play an important role in supporting functioning in the short term, my work also reveals that their contributions may be less evident when considered over longer periods. Chemical perturbations caused by anthelmintic residues represent a significant threat to some invertebrate groups, but my experiments show that exposure does not always translate into an immediate reduction in ecosystem functioning. While use of anthelmintic products with relatively low toxicological risk did not cause obvious reductions in function, my work shows exposure can have significant consequences for the conservation of sensitive species. Overall, my work highlights the need for multigenerational studies, mathematical modelling, and careful consideration of sublethal effects to assess fully the risks of anthelmintic residues in the pasture environment. Furthermore, the emphasis on dung beetles (rather than other dung-associated invertebrates) in the existing literature neglects potentially important functional benefits provided by other taxa, such as earthworms. As the global human population continues to expand, it is important that we find sustainable ways to produce food while simultaneously conserving biodiversity. As loss of biodiversity in agricultural ecosystems does not always have functional consequences, it is important that wider justifications for conservation remain integrated into agricultural policy and practice.

As bacteria are becoming resistant to conventional antibiotics, researchers are looking for new ways to combat microbial infection. We have begun to adopt genetic and functional genomic approaches to define the molecular determinants of pathogen resistance in the dung beetle, Euoniticellus intermedius. This dung beetle survives microbe-rich environments such as dung. This ability makes it a potential model for the study of infectious agents and ecological damage. To date, E. intermedius has not been studied at the molecular level. In this study, a range of complimentary analytical techniques were used to characterize the E. intermedius embryonic cell line established in our laboratory. These techniques characterize morphology, growth characteristics, karyotype, isoenzyme patterns and embryonic development. Complete characterization of the E. intermedius cell line is essential for the cell banks and for the regulatory requirements in biopharmaceutical production. This study followed gene sequences and their comparisons for both adult and cell line to confirm that the E. intermedius (EISA08) cell line is originated from the embryonic E. intermedius dung beetle. cDNA was synthesized from mRNA isolated from E. intermedius adult beetles and cell line (EISA08) was sequenced using GS (FLX) technology by a commercial facility, Inqaba Biotechnical Industries (Pty) Ltd, South Africa. In addition to characterization of the cell line, two genes, namely hopscotch and ribosomal protein S9 (RpS9), were selected from the Flylab genome data base. The E. intermedius database is a web-based system for the genome and transcriptome of the dung beetle to evaluate the immune system of the dung beetle (http://Flylab.wits.ac.za/). hopscotch was selected because it is believed to be involved in the JAK-STAT signalling pathway for anti-viral response, embryonic development and cell growth. Rsp9 was chosen as a loading control because it is expected to be a housekeeping gene. The conserved molecular signalling pathway JAK-STAT is used by E. intermedius (as in other insects and humans) for immune defence and early embryonic development. The project followed hopscotch and Rsp9 gene expression in all the E. intermedius life cycle developing stages; adult, pupae, larvae, embryo, and cell line cell growth, life cycle developing stages and embryonic development has was monitored. E. intermedius embryonic development is described as short germ-band. E. intermedius embryogenesis is regarded as basal and is observed in most arthropods. The study revealed that E. intermedius hopscotch is over expressed in the early developing stages, embryo, larvae, and pupae and in the newly established cell line EISA08. The results from this study lead to the suggestion that E. intermedius JAK-STAT pathway is activated early and has an important role in embryonic development, cell proliferation and immune defence. Studies of E. intermedius could provide more insight into the properties and evolution of innate immunity and embryonic development.

Thesis (M.A.)--The University of North Carolina at Greensboro, 2010. / Directed by Jan Rychtar; submitted to the Dept. of Mathematics and Statistics. Title from PDF t.p. (viewed Jul. 5, 2010). Includes bibliographical references (p. 54-57).

Spirocercosis is a canine disease caused by the nematode parasite Spirocerca lupi (Rudolphi, 1809) (Spirurida: Spirocercidae) and is a potentially fatal condition in domestic dogs (Canis familiaris). The larval life cycle of this parasite involves intermediate and paratenic (transport) hosts. Various species of coprophagous dung beetles (Scarabaeidae: Scarabaeinae) serve as the principle intermediate hosts. Despite extraordinary advances in biomedical research, it is unlikely that these alone will alleviate the burden of this parasitic disease in dogs. Recently, there has been growing concern over the upsurge in incidence and reported cases of spirocercosis in domestic dogs in South Africa. There is a plethora of literature on the clinical, diagnostic and epidemiological aspects of this disease in dogs, yet no study has aimed at fully understanding the dynamic interactions between the various hosts and S. lupi, governed by the consequences of their behaviour under different and ever-changing environmental conditions. It is most likely that the impact of this disease is accentuated by constant changes in human demographics and behaviour. Studies on spirocercosis in dogs have considered the consumption of the various paratenic hosts or the deliberate ingestion of dung beetles to be the main cause of the transmission of S. lupi to dogs. However this study suggests that the coprohagous behaviour of dogs and the subsequent accidental ingestion of coprophagous dung beetles in or on faeces are mainly responsible for the transmission of this parasitic nematode to dogs. Changes in urban land use and subsequent changes along urban-rural gradients influence the nature of biological interactions partly due to changes in species assemblage structure and composition. Such alterations in assemblage structure of species pose a particular risk to altered rates of parasitism and disease transmission. It is concluded that these changes in landscape use coupled to altered dung beetle species assemblage structure have influenced the pattern of events observed in this host – parasite relationship. Furthermore, the social organization of domestic dogs (pets versus feral animals) and the availability of exposed excrement as a direct or indirect consequence of human behaviour played a pivotal role in the rate these parasites are transmitted to dogs. / Thesis (PhD)--University of Pretoria, 2012. / Zoology and Entomology / unrestricted

Alpacas have been gaining prominence in the U.S. since the early 1980s. In pastures, dung beetle activity has been shown to enhance the degradation and incorporation of dung into the soil. The benefits of this activity have been quantified for cattle, but not for alpacas. The objectives of this study were to document the dung beetle species present in alpaca pastures, and to evaluate the impact of dung beetle activity on the growth of a common summer annual grass. In 2010 and 2011, dung beetle species present in alpaca pastures located at Virginia State University (VSU), were evaluated weekly from late May until late August. Eleven species of dung beetles were found, with Onthophagus taurus Schreber being the most dominant. In 2011, a greenhouse study was conducted at Virginia Tech's Southern Piedmont Research Station. Treatments included a control (no dung, no beetles), dung only, dung with five pairs of O. taurus, and dung that was allowed to be colonized in alpaca pastures at VSU. The addition of O. taurus and the field colonization both significantly increased total yield over the no dung control by 10% and 14%, respectively. These results indicate that healthy and diverse dung beetle communities occur in alpaca pastures in the mid-Atlantic region, and that the presence of these beetles would likely enhance nutrient cycling and pasture growth. However, it is important to remember that dung beetles are just one component of many found in a healthy grassland ecosystem, and the functions of these components are interrelated. / Master of Science

Upland grasslands comprise a large proportion of the UK’s land area and are primarily used to graze sheep. These grasslands store large quantities of carbon (C). Changes in land use or climate could affect the ability of these soils to store C and the fluxes of other greenhouse gases associated with agricultural soils, nitrous oxide (N2O) and methane (CH4). Grazing substantially changes the cycling of C and nitrogen in grassland ecosystems, particularly through the deposition of rapidly degrading excreta, both dung and urine, on the soil. The major non-enteric greenhouse gas emissions associated with this type of extensive farming of ruminants are the emission of N2O and CH4 from soils affected by the animal’s excreta. This PhD project has investigated the cycling of sheep dung in two upland soils of different management regimes to investigate the effects imposed by the plant community. Dung incorporation was measured by capitalising on the natural difference in natural 13C abundance (δ13C ratios) between maize and native British vegetation, which permitted maize-derived sheep dung to be used as a 13C tracer of dung incorporation into soil. A physical and chemical soil fractionation methodology was used to isolate the distinct soil organic carbon (SOC) pools and ascertain the location of the dung C. There were differences between soils in dung C cycling, with more dung C being measured in semi-improved soils at experiment’s end. Throughout the one year timeframe of this experiment, most of the dung C was recovered in the particulate organic matter fraction. Changing the plant community did not have a measurable effect on dung C cycling within the experimental period. Urine patches in grazed pastures represent a major source of agriculture’s N2O emissions. The N2O, CH4 and CO2 fluxes from chambers treated with synthetic urine, synthetic urine and dung, or dung, and an untreated control in randomised block design at two sites were measured over one year. Relevant soil parameters were also measured at each sampling point. From this data N2O emission factors for sheep excreta at these sites were calculated. N2O emission factors were significantly different between sites, were different for dung and urine, and in all cases were less than the current default value used by countries utilising a Tier 1 methodology, according to the IPCC, to inventory N2O emissions derived from grazing livestock. Dietary manipulation has been proposed to increase certain components in urine that are thought to inhibit N2O emission with the aim of reducing livestock greenhouse gas emissions. One such urinary component is hippuric acid. Soil to which synthetic urine with incrementally increased quantities of hippuric acid were added were incubated, as were soils to which dung only and dung and synthetic urine had been added, as well as an untreated control. No significant effect of hippuric acid concentration was observed. N2O emissions from the dung only and dung and urine treatments were unusually high and surpassed those of the urine only treatments. This has been hypothesised to be due to fungal denitrification in the dung treatments or suppression of microbial activity due to ammonia toxicity in the urine-treated soils. The key conclusions from this PhD work are that the effect of dung deposition on SOC cycling may be quite small and appears to result in substitution of native SOC with dung C, rather than an increase in SOC; N2O emissions from sheep dung and urine deposition in semi-improved grasslands is likely to be very low and much lower than the current IPCC default value; and that in our incubation experiment there was no discernible impact of hippuric acid on N2O emissions, but it is possible that this is an experimental artefact.

Dung beetles is a group of coprophagous beetles in the family Scarabaeidae. Dung beetles have an important function by improving nutrient circulation and biological control of parasites. Dung is a short-lived resource, making dung beetles tied to habitats continuously grazed. Decline in pasture combined with shorter grazing seasons has resulted in a decrease in available dung. Other reasons can be the use of chemicals to control internal parasites on the grazing animals. This has contributed to the fact that half of the dung beetles in Sweden are endangered. The aim of the present study was to analyze data on dung beetles from the County Administration Board in Östergötland and see if species communities have changed between 2001-2019. In addition, the effect of sand as soil type was studied by comparing the species richness between pastures with and without sand. Analysis whether there was any variation among species richness and species communities depending of grazing animals was also performed. Results showed that the number of species had increased over time and that changes in species communities had occurred. Pastures with sand had more species, however, the amount of sand in the nearest surroundings was of less importance. Dung beetles were found to have a preference when choosing dung-type. Pastures with dung from multiple species of grazing animals were found having the highest species richness. Studies on this would clarify even further what seems to favor dung beetles, this could then be applied to other areas to counteract the loss of species.