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Free roaming domestic cats (Felis silvestris catus) are widespread around the world. Whether they are owned or not, their presence and management raises strong opinions between supporters of “cat independence”, advocates of “cat safety” and defenders of wildlife, leading to suggestions that cats should have their freedom to roam outdoors restricted. The aim of this thesis was to get a precise understanding of the concepts of free roaming and containment in cats, their meaning for the relationship between cats and the society that they are living in, both from the cats’ ‘point of view’ and the perceptions of their owners, and the impact on cat welfare. Using a variety of approaches including a survey, GPS tracking, behavioural tests and an owner-based questionnaire, we showed that although many people’s perceptions about free roaming cats depended on their residential location and their ownership status, the risk of road traffic accidents was rated highly as a concern by people regardless of their residential location or cat ownership status. This perception was matched by the behaviour of free roaming cats themselves, who, regardless of their home location were observed to frequently engage in risky behaviour like frequent road crossing. This represents a high risk to their wellbeing and, combined with the other risks posed to cats that go outside, makes a clear case for the need to restrict the cat’s roaming behaviour, in order to protect its welfare. Given the problems of an indoor only lifestyle, which may perhaps be greater than is widely recognised, there is a case for examining the impact on cat welfare of an effective containment system, that restricts the cat to the boundaries of its owner’s property (both minimising risk to the cat and disruption to the community). Options for containment are limited, and little is currently known about their impact. Therefore I examined the impact of an electronic containment system that is widely thought to be effective but that also causes concern regarding its effect on cat welfare. This was the first research on such a system in cats, and I sought to establish if the welfare concerns were justified and outweighed by the potential benefits. First, I gathered initial information with a case series, and then I carried out a more comprehensive study with a larger sample of cats. The initial case series failed to establish clear evidence of a consistent negative impact on welfare. In the larger follow-on study, for the population studied, I found no evidence consistent with a long term negative impact of the electronic containment system on cat behaviour and welfare. Indeed, cats contained by the system interacted more with people, were more curious about novel objects and were no more sensitive to sudden noise than control cats, although whether these effects were due to the system or selection bias in the volunteers remains unknown. viii Although many research questions have been addressed, unanswered questions remain, and directions for future research have been identified and are discussed.

Arousal and distress are considered important factors when dogs show problematic behaviours and the crucial role of hormones and neurotransmitters involved in stress responses is widely recognized. Corticosteroids are important players in stress responses and, along with other hormones and neurotransmitters, contribute to the onset of both physiological and behavioural changes that can be either normal and adaptive or excessive and maladaptive depending on several factors. A literature review revealed that exogenous corticosteroids have been reported to change behaviour in human beings and laboratory animals but no data were available as far as similar e�ffects in dogs. The aim of this research was to identify possible behavioural changes in dogs treated with corticosteroids. In the fi�rst study, the perception of behavioural changes in dogs during corticosteroid therapy was investigated through semi-structured open interviews of the owners of 31 dogs of di�fferent breeds, genders, and ages. All dogs had received corticosteroid therapies in the past six months. Owners were asked to describe their dog's behaviours both on and o� corticosteroid therapy. Eleven owners reported behavioural changes in their dogs; nine dogs were reported to show more than one behavioural change. Six dogs reportedly showed nervousness and/or restlessness, three showed an increase in startle responses, three showed food guarding, two showed a decrease in their activity level, three showed an increase in avoidance responses, four showed irritable aggression, and two dogs increased barking. Semi-structured interviews can be useful preliminary tools for the identifi�cation of areas of future investigation, and the outcomes of the interviews were then used to investigate more rigorously the possible relationship between these signs and corticosteroid use in dogs. In the second study 99 dog owners were asked to complete a 12 item questionnaire, developed following the results of the previous survey. Owners were asked to evaluate their dogs' behaviour on and off� therapy, using a seven point scale. A sample of owners whose dogs were receiving treatment for dermatological, orthopaedic or other conditions completed the survey. The survey was completed by 44 dog owners with animals receiving treatment with a range of corticosteroid preparations (mainly prednisolone and methylprednisolone) and 54 dog owners with dogs receiving treatment with other drugs, mainly antibiotics and non-steroidal anti-infl�ammatory drugs. Dogs under corticosteroid treatment were reported to be signifi�cantly less playful, more nervous/restless, more fearful/less confi�dent, more aggressive in the presence of food, more prone to barking, more prone to startle, more prone to reacting aggressively when disturbed, and more prone to avoiding people or unusual situations. The last part of this study involved behavioural tests of dogs. Eleven �treatment� dogs were then tested twice: before and during corticosteroid treatment with either methyl-prednisolone or prednisolone to assess their sensitivity to a potentially aversive stimulus. Eleven control dogs, not receiving corticosteroid therapy, were also tested at the same time intervals in the same environment. Dogs were exposed to a brief dog growl while they explored some bowls containing food and their behaviour was video recorded. Treatment dogs investigated the area for signi�ficantly less time and ate signi�cantly less food in the second test trial when on corticosteroid compared to control dogs. In �final study, exploring relationships between corticosteroid therapy and dogs with behaviour problems, a review of the caseload of the author of 345 dogs reported for behaviour and management problems was analyzed. It was found that 16 % of them had a history of previous treatments with corticosteroids. Previous treatment with corticosteroid was found to be signi�ficantly associated with negative aff�ective states. These results support earlier preliminary �findings concerning possible adverse behavioural side e�ffects following the use of corticosteroids in dogs, and the possible need for concomitant behavioural advice when these drugs are used in general veterinary practice.

Three experiments were conducted to study the impact of growth-promoting levels of various antimicrobials on performance and the development of antibiotic-resistant commensal bacteria in swine. In experiment one, feeding subtherapeutic levels of antibiotics, or high levels of zinc and copper did not improve growth performance of nursery pigs housed in a biosecure facility that were farrowed from sows not previously exposed to antibiotics. In experiment two, feeding nursery pigs obtained from a commercial source high levels of zinc resulted in increased ADG and ADFI compared to pigs fed a diet containing no antimicrobials or high levels of copper. In experiment three, subtherapeutic levels of chlortetracycline improved ADG, ADFI, and G:F for only the first week after weaning. Performance improvements were not observed for finishing pigs fed subtherapeutic levels of virginiamycin compared to pigs fed no antibiotics. High levels of zinc may be as effective as subtherapeutic antibiotics at improving nursery pig performance. The use of antimicrobial growth-promoters in clean, well-managed facilities with high labor inputs will not improve growth performance of swine. Feeding various antimicrobials were ineffective at reducing the total number of commensal bacteria isolated from pigs in any study. Although pigs in experiment one were farrowed from sows not exposed to antibiotics for over 33 years, commensal bacteria isolated from these pigs exhibited resistance to multiple antibiotics. E. coli resistant to neomycin were isolated only from pigs fed diets containing subtherapeutic antibiotics in experiment one. In experiment two, feeding pigs diets containing growth-promoting levels of antibiotics, zinc, or copper resulted in increased percent of E. coli resistant to tylosin, erythromycin, and copper. Feeding a diet with subtherapeutic levels of tylosin and sulfamethazine also increased the percent of Enterococcus resistant to tylosin, sulfamethazine, and erythromycin compared to pigs fed no antimicrobials or high levels of zinc. While fluctuations in antibiotic resistance were observed between treatments in experiment two, there were no differences between treatments in percent of bacteria resistant to any antibiotics at the conclusion of the trial. In experiment three, percent of E. coli and Enterococcus isolated from pigs that were resistant to chlortetracycline and virginiamycin fluctuated when monitored for a 19 week grow/finish study, however no differences in percent of resistant bacteria were observed between pigs fed diets containing no antibiotics or growth-promoting levels of antibiotics at the conclusion of the trial. In the fourth experiment, manure from pigs receiving growth-promoting antibiotics was spread on soil boxes and subjected to a simulated rainfall event to measure antibiotic resistance in water runoff. A greater amount of antibiotic resistant bacteria were recovered from water runoff at the initial sampling period compared to sampling 30 min after runoff began. Percent of antibiotic resistance isolated from swine can fluctuate over time. Development of antibiotic-resistant bacteria may be increased by the use of antimicrobial growth-promoters, however, resistant bacteria are present in swine facilities regardless of the use of their use. These resistant bacteria can potentially enter the environment through land application of manure. Antibiotic resistance will not be easily reversed by removal of antibiotics from livestock feeds.

This experiment evaluated rumen protein:energy synchronization in steers fed either gamagrass (Tripsacum dactyloides) or orchardgrass (Dactylis glomerata) hays with or without a soybean hull/corn supplement. A N balance trial was conducted to compare the effects of the supplement and hay on N intake, N digestion, and N metabolism. The supplement consisted of 50:50 corn: soybean hulls mix with 50 g molasses per kg of corn: soybean hulls mixture. The supplement contained 11.3% CP, 34.2% NDF, 22.9% ADF, and 0.87 kg was fed at 0830 and 1600 followed by hay offered in two equal portions. Steers had ad libitum access to water and a trace mineralized salt block throughout the study. Hay compositions were 8.3% CP, 71.8% NDF, and 37.8% ADF for gamagrass and were 11.9% CP, 70.5% NDF, and 36.6% ADF for orchardgrass. Steers were individually fed, blocked into two weight groups, and randomly assigned to either gamagrass or orchardgrass hay (4 steers per hay). Within hays, steers were assigned to receive supplement or no supplement in a crossover design. Ad libitum DM intake for each steer was equal to their intake during the last 8d of the 21-d ad libitum period. Steers were then placed in metabolism crates for an 8-d adjustment followed by a 5-d balance trial. During the balance trial, steers were fed 90% of ad libitum intake. Compared with gamagrass, orchardgrass had similar true IVDMD (64.2 vs 62.2%), similar leaf true IVDMD (58.2 vs 63.2%), and similar stem true IVDMD (46.7 vs 51.7%). Effects were significant at P < 0.10. Compared with gamagrass, orchardgrass had a lower ad libitum DM intake (4.62 vs 5.37 kg/d), higher N intake (96.6 vs 81.1 g/d), similar fecal N (36.1 vs 34.5 g/d), higher N digestibility (62.4 vs 57.4 %), similar N retained (27.2 vs 27.7 g/d), and lower digestible DMI (3.20 vs 3.53 kg/d). Compared with no supplement, supplement increased digestible DM intake (3.70 vs 3.03 kg/d), total DM intake (5.87 vs 5.07 kg/d), N intake (96.9 vs 80.8 g/d), fecal N (39.4 vs 31.1 g/d) and N retained (31.7 vs 23.2 g/d). Supplement (1.74 kg/d) decreased hay ad libitum intake by 0.73 kg/d. Supplement decreased, blood urea N, urine urea N and urine urea N as a percentage of urine N more for orchardgrass than for gamagrass. Supplement tended (P < 0.11) to improve N retained as a percentage of N intake or percentage of N digested more for orchardgrass than for gamagrass hay. Blood urea N was reduced (2.21 vs 0.14 mM)more for steers fed orchardgrass hay than for steers fed gamagrass. We believe that the increase in digestible OM intake is due in part to the presence of soybean hulls in the supplement.

Poultry-related salmonellosis is an on-going problem that the poultry industry must continue to address. To address these challenges, Salmonella populations present on litter and fecal samples of brooder and grow-out turkey farms were assessed using a quantitative procedure. Furthermore, serotyping, genotyping by pulsed-field gel electrophoresis and antibiotic resistance-susceptibility analyses were used to investigate the diversity of the Salmonella serotypes present on these farms. Additionally, alternative on-farm pathogen intervention strategies including feeding whole or coarsely ground grains, increasing insoluble fiber content of the diet and use of an alternative non-litter cage-based housing design (Broilermatic System) were evaluated. Salmonella litter populations averaged 2 logs higher in 3-wk turkey samples compared to samples from 19-wk birds. Turkey age also influenced Salmonella serotypes, genotypes and antibiotic resistance profiles. Only serovars Javiana and Mbandaka were common between 3 and 19-wk old turkeys. A higher frequency of multidrug resistance was observed in Salmonella isolates recovered from samples of 3-wk birds, on average isolates were resistant to >4 antibiotics tested. Supplementing coarse ground corn and increased insoluble fiber (wood fiber) content into the turkey diet did not adversely impact body weights. However, the treatments did not influence Salmonella colonization or fecal shedding of turkeys. To examine the impact of housing design and addition of whole or coarsely ground grains on performance, intestinal microbial diversity and Salmonella colonization, broilers were reared on four diets consisting of finely or coarsely ground corn and finely ground or whole triticale to market age and Salmonella populations measured. Whole grain supplementation decreased Salmonella cecal populations while rearing broilers on litter floor as opposed to the Broilermatic System resulted in significant reductions in Salmonella cecal populations. Moreover, feeding whole triticale presumably encouraged the proliferation of bacterial populations which may have competitively excluded Salmonella in the ceca of broilers. In conclusion, highly variable Salmonella populations and serotypes were detected across all commercial turkey farms and the use of alternative feed ingredients such as triticale may help to reduce Salmonella colonization in poultry. Moreover, diet composition and grain coarseness as well as housing design can influence the diversity of the commensal intestinal microflora which may help in the control of Salmonella colonization in broiler intestines.

Studies were conducted to develop and analyze gilt estrous behavior traits. Variance components, genetic correlations, and genetic line differences were estimated for gilt estrus, puberty, growth, composition, structural conformation, and first litter sow reproductive measures. Four groups of Landrace-Large White gilts (n=1,225, GIS of NC) from 59 sires and 330 dams were utilized. Heritability (h2) estimates for estrous traits; estrus length, maximum strength of standing reflex with a boar, total strength of standing reflex with a boar, maximum strength of standing reflex without a boar, total strength of standing reflex without a boar, vulva redness, strength of vulva reddening and swelling (VISUAL VULVA), and vulva width were 0.21, 0.13, 0.26, 0.42, 0.42, 0.26, 0.45, and 0.58, respectively. For puberty traits; age at puberty, puberty weight, puberty backfat, and puberty longissimus muscle, h2 estimates were 0.29, 0.39, 0.41, and 0.38, respectfully. The h2 of whether or not a gilt farrowed a litter (STAY1) was 0.14. Age at puberty had favorable genetic associations with estrus length, maximum strength of standing reflex with a boar, vulva redness, STAY1, and age at first farrowing (AFF) (-0.23, -0.32, 0.20, -0.27, and 0.76, respectively). Genetic correlations between estrus length and the standing reflex traits with STAY1 (0.34 to 0.74) and AFF (-0.04 to -0.41) were positive and negative, respectively. Growth rate had unfavorable genetic correlations with estrus length, the standing reflex traits, vulva redness, STAY1, and AFF (0.30, 0.14 to 0.34, -0.19, 0.52, and -0.25, respectfully). Backfat had unfavorable genetic associations with estrus length, age at puberty, and first litter total number born (TNB1) (0.29, -0.26, and 0.47, respectively). Vulva redness and TNB1 had favorable phenotypic and genetic correlations (-0.14 and -0.53, respectively). For estrous traits, crossbred performance was superior to the pure-line average for estrus length, total strength of standing reflex with a boar, vulva redness, VISUAL VULVA, and vulva width. These findings imply the use of F1 females would increase estrus length and improve vulva traits. The unfavorable genetic associations between production and reproduction traits further strengthen the need for a balanced selection objective. Based on these results it was concluded that selection for a younger age at puberty would have correlated responses of improved gilt estrous behavior and sow reproductive lifetime.