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Following the argument of cultural change between the Romano-British and Anglo-Saxon periods in Britain, the purpose of this thesis is to find evidence of change in human diet and animal husbandry in the Upper Thames Valley across this boundary. Research questions are set to find differences in human diet, animal diet, and birth seasonality of herbivores at Horcott, a site showing human activity in both periods. Stable carbon and nitrogen isotope measurements on collagen from humans and livestock animals and enamel carbonate extracted from herbivores were analysed. Results showed changes in the diets of cattle, sheep/goats, pigs, and human, and birth seasonality of cattle and sheep/goats. These changes were argued to have been caused by differences in the intensity of fertilising crop fields, the amount of animal protein fed to adult pigs, the amount of non-local food in human diet, and the significance and purpose of livestock rearing and the preference of dairy products. The outcome of this thesis enhances the understanding of: a) the strategy and the amount of human effort put into crop cultivation and livestock management; b) the availability and preference of food for humans depending on the period; and c) the site-dependent differences in the extent of change in the course of transition between the Romano-British and Anglo-Saxon periods. This thesis demonstrates the importance of animal data in order to discuss human diet, and the advantage of modelling enamel carbonate sequential data when analysing worn and shortened teeth.

Purpose Intensive livestock grazing has been associated with an increased risk of soil erosion and concomitant negative impacts on the ecological status of watercourses. Whilst various mitigation options are promoted for reducing livestock impacts, there is a paucity of data on the relationship between stocking rates and quantified sediment losses. This evidence gap means there is uncertainty regarding the cost-benefit of policy preferred best management. Methods Sediment yields from 15 hydrologically isolated field scale catchments on a heavily instrumented ruminant livestock farm in the south west UK were investigated over similar to 26 months spread across 6 years. Sediment yields were compared to cattle and sheep stocking rates on long-term, winter (November-April), and monthly timescales. The impacts of livestock on soil vegetation cover and bulk density were also examined. Cattle were tracked using GPS collars to determine how grazing related to soil damage. Results No observable impact of livestock stocking rates of 0.15-1.00 UK livestock units (LU) ha(-1) for sheep, and 0-0.77 LU ha(-1) for cattle on sediment yields was observed at any of the three timescales. Cattle preferentially spent time close to specific fences where soils were visually damaged. However, there was no indication that livestock have a significant effect on soil bulk density on a field scale.

Forested lands contribute to the United States (US) economy by providing livestock and timber production. Livestock grazing of forested lands has been widespread throughout the western US since the settlement era, and currently occurs on 51.4 million hectares (ha) representing 16% of all US grazing land and 22% of all US forested land (Nickerson et al. 2011). While livestock grazing and timber harvest are occurring on a substantial amount of forested land, relationships between management practices, tree stocking, timber production, forage production, livestock grazing, wildlife, aesthetics, and ecological integrity are not well documented. Whether considering timber or cattle, finding a balance between production and resource conservation is a fundamental challenge to agricultural producers, and is often a tradeoff between short term gains and long term sustainability. This dissertation aims to identify livestock and timber management practices that optimize production and are ecologically conservative. Specifically, I focused on three objectives. First, I reviewed the published literature and summarized what is known about best-practices for concurrent management of livestock and timber production in pine forests in the US. I found most studies came from the southeastern and western US where timber and livestock production on the same land unit are common. The relationship between pine cover and forage seemed fairly consistent across the US, and production was optimized when cattle grazed open canopy forests with basal areas between 5 and 14 m2 ha-1 (15-35% tree canopy cover). Second, I developed forest cover maps to estimate forage production in the Black Hills, South Dakota (SD) for the period from 1999 to 2015. I developed a regression model based on Landsat and Ikonos satellite imagery and was able to detect large changes in forest cover over time. I then used these maps in combination with maps of soil type and Palmer Drought Severity Index (PDSI) to update forage production estimates for the region. These changes in forest cover have large implications for forage production in the Black Hills. Over the 15 year period, mean tree cover decreased in 181 pastures in the Mystic Ranger District by 17.6 ± 0.6%, and there was a corresponding 15.5 ± 0.6% increase in mean forage production. Third, I conducted a 2 -year field experiment in the Black Hills, SD to study the relationships between management practices such as livestock stocking rates, grazing pressure, and timber harvest history, and aspects of resource condition such as tree regeneration, forage production, and plant community composition. From 2014-2015, I visited 44 pastures across a spectrum of management practices and measured seedling regeneration (590 plots), plant species richness (393 plots), primary production (246 plots), and visual obstruction (120 transects). I found that cattle grazing did not affect ponderosa pine regeneration. Grazing did affect plant diversity, and I found the highest plant diversity in areas of moderate grazing pressure. This work suggests that moderate stocking rates should have no effect on the timber industry but could positively affect native plant diversity. In the conclusion, I summarize what I learned from the literature review, mapping exercise, and field study and provide some management recommendations based on this work. Overall, I found that updated forage production estimates based on satellite imagery, and using grazing pressure index (GPI) to identify optimal stocking rates are tools that can facilitate management of livestock and timber production in the Black Hills, SD.

Predicting ewe maternal success and measuring maternal bond strength remain, to an extent, topics of mystery. The optimization of management strategies will always be an important goal for any livestock farmer. Optimizing maternal success at lambing time is an essential point of focus for any farmer hoping to profit from his or her flock of sheep. As more is understood about the behavioral tendencies related to maternal success, management systems will be tailored to lower labor requirements, making sheep farming less stressful for those involved and encouraging the growth of the sheep industry. Any tactic that can work toward the goals of decreased labor and increased production, while preserving or enhancing animal welfare, should continue to be thoroughly explored. Allowing for and encouraging the natural expression of innate behaviors to achieve these goals, particularly including maternal behavior, will remain an important area of focus in keeping sheep production viable.

The New Zealand dairy farm system is based on a seasonal calving interval with the system being reliant on seasonal pasture production. A seasonal calving interval requires all cows to reproduce every 365 days. Farmers typically experience difficulty in achieving this 365 day cycle and hence the practice of induced parturition has been widely used. Induced parturition has become internationally unacceptable and the New Zealand dairy industry has set a target for

During the past fifteen years major, changes in the management of livestock have occurred in Southland. The area of forage crops for wintering stock has greatly decreased with the development of low cost wintering systems. The change in emphasis from crop to grass wintering of livestock may have affected production per animal and per hectare. Several farming systems are explored in this study and linear programming is used to develop an optimal farming system. Farm areas are analysed to expose existing resource restrictions and to define representative farm input levels for use in the linear programme. These representative farms were developed for the Gore and Invercargill areas. Chapter I deals with livestock management practices in Southland, defines the representative farms arid details farm production trends in Southland. Chapter II reviews the literature on grazing dynamics of pasture and forage crops and discusses the feed supply and demand alternatives used in the study. In Chapter III the method of costing the feed alternatives is outlined. The linear programming matrix is developed and critical areas delineated. Chapter IV gives detailed results of the study and discusses the relevance of the results. Chapter V summarizes the inputs required and levels of production achieved under the optimal farming system and outlines the implications for Southland.