Cathepsin D has been postulated to play a role in the tenderization of meat with ageing. Meat toughness has been related to connective tissue content and degree of myofibrillar shortening. This investigation was undertaken to determine the activity of cathepsin Don bovine intramuscular connective tissue. Highly purified cathepsin D preparations from bovine spleen and bovine sternomandibularis muscle were obtained by ammonium sulfate fractionation followed by affinity chromatography on pepstatin coupled to controlled pore size alkyl amine glass beads . Maximum proteolytic activity using hemoglobin as substrate was obtained at pH 3.5 and 3.8 for bovine spleen and muscle cathepsin D, respectively. The banding pattern of bovine spleen cathepsin D on SDS-polyacrylamide gels was identical to that of a commercial preparation. Both cathepsin D preparations had 2 major proteins with molecular weights of about 45,000 and 35,000 daltons. Bovine muscle cathepsin D preparations had 4 polypeptide bands corresponding to molecular weights of 57,000, 45,000, 41,000, and 20,000 on SOS gels . The 45,000 and 41,000 dalton components of muscle cathepsin D were shown to undergo degradation to release peptides of about 20,000 daltons during refrigerated storage of the 40-70 % ammonium sulfate fraction. Cathepsin D from neither of the tissues had proteolytic action towards intramuscular connective tissue isolated from bovine shank muscle over the pH range 3. 0- 4.5 following incubation for 24 hat 37 C. However, a commercial preparation of pineapple stem bromelain was found to degrade connective . tissue , resulting in a release of 44,000 and 64,000 dalton peptides. Degradation was maximum at pH 3.0 and the rate of degradation decreased with pH increase. The failure of a highly purified cathepsin D preparation to degrade connective tissue is a clear indication that the meat tenderizing effect of cathepsin D during meat ageing is not due to its proteolytic action on intramuscular collagen, but due to its reported proteolytic action towards myofibrillar proteins.

I conducted 6 years of field work to evaluate the habitat use and population dynamics of an experimental release of elk (Cervus elaphus) into Great Smoky Mountains National Park (Park). Elk exhibited relatively small home ranges (female: 10.4 km2 and males: 22.4 km2) and movement distances decreased over time. I calculated survival rates (x = 0.73–0.93) and litter production rates (x = 0.73) for the population. To assess the potential for a long-term elk population, I incorporated those vital rates into the population modeling software Riskman and tested its sensitivity to any given vital rate. The projected population growth was positive (1.03, SD = 0.001) and the probability of extinction in 100 years was minimal (1%, SD = 0.001). However, the model was sensitive to adult female survival, and the simulated annual deaths of only 4 adult females increased the probability of extinction to 45% (SD = 0.021). Compositional analysis detected a strong preference for grassland areas by elk in the Park. I used spatial data to identify potential habitat for elk on a multivariate level by calculating the Mahalanobis distance (D2) statistic based on the relationship between elk locations and 7 landscape variables. The D2 model indicated that the best elk habitat primarily occurred in areas of moderate landscape complexity and edge denisty and gentle slope, and was limited in the Park. At the current small population density, elk had minimal impact on vegetation inside the Park and their diet consisted primarily of graminoids. The elk population at Great Smoky Mountains National Park will likely remain small and vulnerable to extinction for some time due to low growth rates, high environmental stochasticity, and limited habitat. Active management (e.g. predator management, prescribed burning, and mowing) will be required to maintain this population until the population grows to more sustainable levels.

Several properties within Tennessee were managed under a quality deer management (QDM) philosophy from 1998 to 2006. Harvest characteristics of three private properties and three Wildlife Management Areas (WMAs) were compared to determine effects on buck harvest rates and the age structure and sex ratio of the harvest. Average annual buck harvest decreased at most areas following antler restrictions and ranged from 55 to 68% of pre-QDM levels because younger bucks were protected. Although the raw numbers showed an increase in older-aged bucks harvested following antler restrictions, when calculated on a per hunter or per permit issued basis, statistical increases were not observed at all study areas. Regardless, hunters at each area felt QDM restrictions were working toward their goal and planned to apply to hunt that area the following season. Most hunters regarded themselves “somewhat knowledgeable” with QDM and considered it a sensible management philosophy. The majority of club hunters (55.5%) and plurality of sportsman license holders (36.9%) and WMA hunters (34.7%) favored a statewide limit of two bucks, and the majority of all hunters favored including does in the harvest and protecting young bucks from harvest. The production and nutritional quality of twenty forages used in food plots and the effects of prescribed burning and understory fertilization on browse production in closed-canopy hardwoods one growing season after treatment were also evaluated. Crimson clover and a cool-season grain (wheat or oats) are recommended to address the mid-late winter stress period, and can be planted with arrowleaf clover to further extend forage availability in the spring. Warm-season annual forages (cowpeas, lablab, and soybeans) supplied forage during the late summer stress period when natural forage quality is low. Ladino clover and chicory supplement production gaps of annual forages. Because of variable results among two sites and because the cost per pound of forage produced following fertilization exceeded $26 per pound, understory fertilization and prescribed fire in closed-canopy hardwood stands are not recommended for increased deer browse. Treatments providing increased sunlight through a reduction in percent canopy cover are much more effective and efficient in providing increased browse.

Variation, or modulation, of suction feeding performance across two prey location treatments, as measured by peak subambient pressure generation, was studied in the Florida largemouth bass, Micropterus salmoides floridanus. Previous studies of suction feeding in centrarchids have excluded possible sources of performance variation to minimize the modulatory response. Florida bass are known to modulate their feeding kinematics when exposed to prey at different levels of elusiveness, and were in turn predicted to vary suction pressure generation when exposed to these conditions. Eight bass fed Palaemonetes sp. shrimp in an open water (elusive) setting and in a vegetated (non-elusive) setting were found to generate significantly different amounts of suction during prey capture (Fli48=5.676, p=0.021). Principal component analysis of variables derived from high speed digital video footage found that the suite of behaviors associated with the feeding strike also differed across prey location treatments. Bass feeding on open water prey approached at higher velocity, exhibited faster cranial kinematics, and generated larger values of suction force, while bass feeding on vegetated prey approached more slowly, had slower cranial kinematics, and generated smaller values of suction. Florida bass clearly modulate their repertoire of feeding activities in response to differing prey capture conditions.

No description available.

<p> Quality is an accumulation of attributes that satisfy customer preferences and expectations. Lamb quality is a moving target that means different things to the supply chain and sheep/lamb industry stakeholders. The objectives of this research were to determine the rank, definition, relative preference, and willingness to pay (WTP) for seven quality attributes and quantify product attributes of lamb at U.S. retail markets. Structured interviews of retail and foodservice respondents were conducted from May 2014 to March 2015 via face-to-face or telephone with lamb/protein purchaser representatives of retail (n = 60), foodservice (n = 45), and purveyor (n = 15) marketing sectors. Shares of preference (relative percentage of preference) in best/worst evaluation for all interviews indicated that eating satisfaction (38.9%) was the most important attribute. </p><p> Shares of preference for all seven specified quality attributes were statistically different from each other (<i>P</i> &lt; 0.05). Credence attributes of origin (17.2%) and sheep raising practices (13.6%) ranked second and third overall, respectively. Physical product characteristic traits of product appearance/composition (10.5%) and weight/size (8.5%) were ranked fourth and fifth in shares of preference, respectively. Nutrition/wholesomeness (7.1%) ranked sixth and product convenience/form (4.2%) ranked seventh in the overall ranking across all sectors of retailer, foodservice, and purveyor interview respondents. </p><p> In WTP analyses, origin (25.8%) and sheep raising practices (20.0%) had the greatest likelihood of being a non-negotiable requirement for lamb purchasers. Eating satisfaction was the trait most likely to receive a premium (71.7%) from buyers, and product assurance of eating satisfaction generated the greatest average WTP premium (18.6%). This research indicated, across all sectors, eating satisfaction, defined as lamb flavor/taste, was the most important quality trait to those who purchase lamb. </p><p> In-store evaluations of retail lamb labels showed that lamb shoulder and loin chops originating from the U.S. garnered the greatest price premiums compared to either New Zealand or Australian lamb (<i>P</i> &lt; 0.05). Lamb was merchandised to American consumers at specialty type stores at an increased price per kg premium than either locally owned or national grocery chains (<i>P</i> &lt; 0.05). Lamb shoulder prices at retail were merchandised with the greatest premium for product of U.S. origin from a specialty store packaged in modified atmosphere packaging and labeled with local (+ $5.42/kg) and natural (+ $5.40/kg) claims (<i>P</i> &lt; 0.05). Lamb loin prices at retail were merchandised with the greatest premium for product of U.S. origin from a specialty store merchandised in a full service case or modified atmosphere packaged and labeled with a source verified and branded (+ $7.21/kg) label claim (<i>P</i> &lt; 0.05). Shoulder and loin chop prices analyzed via hedonic modeling were not different for store location (East, Central, and West) nor USDA process verified Never-Ever 3 claim (<i>P</i> > 0.05). </p><p> Additionally, this research indicated that lamb loin and rib chops purchased at U.S. retail markets originating from U.S. lamb were the most muscular. Loin eye area of loin chops from U.S. origin were greater (19.55 cm2) than Australian chops (16.77 cm²), and chops from New Zealand (14.52 cm²) were the least muscular (<i>P</i> &lt; 0.05). Also, Australian lamb (0.64 cm) had a trimness advantage of external fat of loin chops compared to lamb originating from either the U.S (0.84 cm) or New Zealand (0.86 cm; <i>P</i> &lt; 0.05). </p><p> Lamb producers should strive to place a strategic emphasis on quality attributes identified in this research to ensure eating satisfaction and lamb flavor are optimized for American Lamb, and to produce lamb with product authenticity attributes requested by retail and foodservice sectors, and inevitably American lamb consumers. </p><p> An important application of the research included the development of an American lamb quality mission to: improve the consistency of quality, cutability, and marketability of American lamb with a consumer driven focus. The final phase of this project was a sheep/lamb industry strategy workshop that identified goals to: 1) Address factors contributing to lamb flavor, their impact on consumer satisfaction, and align flavor characteristics with target markets; 2) Improve lamb management to hit market-ready targets for product size, composition, and eating satisfaction while reducing production costs; and 3) Identify and capitalize on market opportunities for American lamb. A continuous improvement mentality is essential to lamb quality management throughout the supply chain in order to maintain (and increase) market share and demand for American lamb. </p>

<p> For long-lived species with perennial, socially monogamous pair bonds and bi-parental brood care, decisions concerning how much to invest in reproduction and whether to remain with a partner could substantially affect lifetime fitness. I studied the fitness consequences of reproductive effort (Chapter 2) and mate change (Chapters 3-5) in black brant geese (Branta bernicla nigricans, hereafter brant), an Arctic nesting goose species with precocial young. I used a 25 year (1990&ndash;2014) dataset collected at the Tutakoke River brant colony (TRC), in southwestern Alaska, USA to investigate these questions. Brant provide an ideal study species because researchers are able monitor large numbers of individuals and obtain unbiased estimates of fitness components throughout their life cycle. In my second chapter, I used experimental manipulations of clutch and broods sizes (i.e., the number of goslings leaving the nest) to understand if the maximal clutch size laid by brant (i.e., 5 eggs) is under ultimate control as a result of tradeoffs between reproduction and residual reproductive value of females. I used the Barker robust design mark-recapture model to estimate two components of female fitness: (1) true survival and (2) breeding probability in t+1. I found no evidence that incubated clutch size affects future fitness of female brant. However, breeding probability in t+1 (0.82 &plusmn; 0.10 [95% CI]) was maximized for females tending 4&ndash;5 goslings and declined for females with smaller or larger brood sizes. Thus, the brood sizes that maximized the residual reproductive value of adult females matched the most common clutch sizes laid by brant. The unexpected result that females tending smaller broods had lower future fitness may result from their smaller family size during winter which may decrease their social status in wintering flocks and result in reduced foraging profitability which may carryover to affect reproduction. My findings support the hypothesis that the maximal clutch size in brant is under ultimate regulation because of tradeoffs with adult residual reproductive value. In Chapter 3, I investigated whether or not mate change influenced reproductive success of female brant. I hypothesized that changing mates could affect reproductive success because (1) new pairs are unfamiliar with each other and (2) females may repair with a male that is an inexperienced breeder (i.e., fewer than two previous breeding attempts at TRC). I investigated the reproductive consequences of mate change using generalized linear models to estimate relative initiation date, clutch size, and the number of goslings leaving the nest and a Cormack-Jolly-Seber mark-recapture analysis to estimate prefledging survival. I found that females breeding with an unfamiliar, but otherwise experienced male fledged at least as many goslings as females breeding with an experienced, familiar mate. However, females who had switched to an inexperienced mate initiated their nests 0.48 (&plusmn; 0.26 [95% CI]) days later and incubated clutches that were 0.17 (&plusmn; 0.10 [95% CI]) eggs smaller than females breeding with a familiar mate. More importantly, goslings attended by a mother who was breeding with an experienced, familiar mate had greater prefledging survival (? = 0.30 &plusmn; 0.04 [95% CI]) than those whose mother had changed mates in year t and paired with an inexperienced male (? = 0.19 &plusmn; 0.04 [95% CI]). These results support the hypothesis that there can be reproductive costs of changing mates for female brant, but male experience rather than familiarity of partners determines these costs. In Chapter 4, I estimated rates of mate retention and investigated if there were long-term fitness benefits of mate retention. This analysis included 3021 and 3039 mature female and male brant who bred at TRC from 1990&ndash;2014. From 1990&ndash;2010, I recorded 748 and 196 breeding attempts after mate change for female and male brant, respectively. I estimated mate fidelity in t+1 of brant that were breeding with a familiar or unfamiliar mate in year t using a multi-strata robust design capture-mark-recapture analysis. I investigated whether breeding with a new mate reduced true survival or breeding probability in t+1 using the Barker robust design capture-mark-recapture framework. I found that mate retention in year t+1 for brant breeding with a familiar mate in year t was high for females (0.881 &plusmn; 0.017 [95% CI]) and males (0.952 &plusmn; 0.013 [95% CI]). However, for individuals who had switched mates in year t the probability of mate fidelity was greatly reduced for females (0.277 &plusmn; 0.163 [95% CI]) and males (0.343 &plusmn; 0.246 [95% CI]). There was also long-term fitness costs associated with mate change. Such that individuals who nested with a new mate had true survival rates which were lower (S females = 0.85 &plusmn; 0.009 [95% CI]; S males = 0.80 &plusmn; 0.017 [95% CI]) than those breeding with a familiar mate in year t (S females = 0.90 &plusmn; 0.006 [95% CI]; S males = 0.89 &plusmn; 0.011 [95% CI]). Additionally, individuals nesting with a new mate had a lower probability of breeding in year t+1 (females = 0.80 &plusmn; 0.035 [95% CI]; males = 0.44 &plusmn; 0.090 [95% CI]) than those breeding with a familiar mate in year t (females = 0.96 &plusmn; 0.008 [95% CI]; males = 0.98 &plusmn; 0.006 [95% CI]). I hypothesize that the demographic costs of mate change are partially related to the relatively low rates of mate retention among newly formed pairs. As a result, individuals breeding with a new mate are more likely to be single for part of the next winter which likely reduces their social status in wintering flocks and results in additional energy expenditure while they attempt to repair. To my knowledge, these results represent the first strong evidence of a link between breeding with a familiar mate and adult demographics in a long-lived bird, with perennial, socially monogamous pair bonds. In my fifth chapter, I investigated factors influencing mate retention and the proportion of female brant that pair with an inexperienced mate after mate change. I predicted that female brant that had undergone a mate change in year t and had paired with an inexperienced breeder or who failed to produce at least one gosling would have low rates of mate retention. I also suspected that brant would pair in a positive assortative manner by body size, previous breeding experience, and age because of the potential fitness benefits of breeding with larger, older and more experienced mates. Contrary to a priori predictions I found that females who had repaired with an inexperienced male were 39% more likely to retain their mate than those who repaired with an experienced male. I found no evidence that successfully producing at least one gosling influenced future mate retention. I recorded 273 cases where experienced female brant switched mates and the new mate was previously marked. In these cases the age of each mate was more strongly correlated (r = 0.26, P &lt; 0.001) than the previous number of breeding attempts by each partner (r = 0.16, P = 0.007). There were weak, but statistically significant correlations between tarsus (r = 0.07, P = 0.012) and culmen (r = 0.07, P = 0.016) lengths of partners (i.e., proxies for structural size). However, body mass during brood-rearing was more strongly correlated among pair members than structural measurements (r = 0.28, P &lt; 0.001). I estimated that about 90% of females who change mates acquire a male who is likely an inexperienced TRC breeder. It is unclear why females who pair with experienced partners have lower rates of mate retention, but it could result from experienced males being in short supply, thereby, enabling them to increase their choosiness in mates. It is clear that most females who change mates will suffer short term reductions in reproductive success, because they will likely acquire partners who are inexperienced breeders. When taken together, the results of chapters 3-5 suggest that there are short and long-term fitness benefits for brant that remained paired with an experienced, familiar partner. These benefits of mate retention may at least partially explain why brant have a perennial, socially monogamous mating system.</p>

<p> Finding ways to objectively measure welfare within different sectors of the beef industry is necessary to continually improve cattle welfare from birth to slaughter. The first objective of Study 1 was to benchmark cow-calf producer perspectives on management strategies and challenges that ultimately affect cattle welfare on ranches in the United States. The second objective of Study 1 was to quantify how producers are marketing their calf crop, their priorities when selecting replacements, and if producers saw value in handling and care guidelines. A total of 1,414 responses from cow-calf producers in 44 states were collected through a survey done in partnership with <i> BEEF</i> Magazine. Thirty questions were asked of producers to gather demographic information, producers&rsquo; current handling and health management practices, and how they prioritized industry challenges. As well as establish at what age and through what avenue producers are marketing their calf crop, and gauge producer perspectives on a quality assessment outlining handling and care guidelines.</p><p> After analyses of producer responses, it was concluded that the frequency of management methods and decisions are impacted by age, operation size, location, and BQA certification. A higher percentage of respondents who were BQA certified used electronic eartags, followed by freeze branding. A higher percentage of respondents not BQA certified used basic eartags and hot branding. 74.5% of respondents were preconditioning their calf crop. A higher percentage of respondents were preconditioning their calf crop that were BQA certified, than those who were not BQA certified. The most important beef industry challenge identified was cow-calf health and the biggest challenge to producer&rsquo;s own operation was identified as land availability/price. The most important animal health issues on producers&rsquo; operations were identified as Bovine Respiratory Disease, flies, Pinkeye, and reproductive health. By producer age, calf/neonate health was identified as the biggest challenge for respondents under the age of 30. Respondents age 55-70 responded that Veterinary Feed Directive (VFD)/regulations was more of a challenge than any other age group. Respondents with 50 head or less or more than 1,000 head more frequently retained their calf crop through finishing and respondents with 51 to 200 head and 201 head to 500 head more frequently backgrounded and then sold their calf crop. 13.5% of respondents answered yes, a veterinarian had offered to administer a drug for pain management when castrating or dehorning. Of those 13.5% who responded yes pain management had been offered, 54.55% of respondents chose to use a pain relief method. A higher percentage of producers that precondition also indicated that they use a pain relief method when castrating or dehorning more frequently, though it was still a low percentage. Overall, 46.3% of respondents saw value in handling and care guidelines and 54.9% of respondents saw value in a program including source and age verification, a vaccination plan, and handling and care guidelines. Respondents who were BQA certified, had a beef cow inventory of 501 to 1,000 head, who preconditioned their calves and backgrounded them before selling, and who lived in the West more frequently saw value in a quality assessment outlining handling and care guidelines.</p><p> The objective of Study 2 was to examine the effects of captive bolt length and breed type on post-stun leg activity in cattle. A total of 2,850 Holstein (HOL) and non-Holstein British/Continental bred (NHOL) steers and heifers were observed post-stunning at a large commercial slaughter facility. A penetrating pneumatic captive bolt stunner was used with three different bolt lengths: CON, 15.24 cm; MED, 16.51 cm; and LON, 17.78 cm. Hind limb kicking, forelimb activity, take away belt stops, carcass swing and number of knife sticks during exsanguination were recorded for each animal from video recording. Hind limb and forelimb kicks observed ranged from 0 to 25 and 0 to 8, respectively. A significant main effect of treatment, breed type and an interaction between treatment and breed type on hind limb activity was found. Analysis of post-stun hind limb and forelimb activity indicated that increasing pneumatic captive bolt length does not decrease post-stun leg activity but alternatively can increase kicking when using the longest bolt tested in particular types of cattle, i.e. Holsteins. Other parameters associated with the shackling and hoisting process were impacted by breed type as well. There was a higher percentage of cattle experiencing take away belt stops and carcass swing in HOL as compared with NHOL. (Abstract shortened by ProQuest.)</p><p>

<p> Adolescence is marked by a period of stress with a portion of these individuals experiencing problems with anxiety. There are physical and psychological benefits of using animal-assisted therapy (AAT) for decreasing anxiety, however, the research on this is limited. The current study expands on the AAT literature by studying the additive effects of AAT along with the frontline treatment for anxiety, Cognitive Behavioral Therapy (CBT). CBT only and CBT + AAT treatment groups followed a structured protocol focused on psychoeducation and practicing coping skills for anxiety using groups of 2 to 4 participants in the school setting. Single subject design and nonparametric statistics were used to analyze treatment data on measures of anxiety and therapeutic alliance from ten students ages 10 to 15 across two school districts. Although the data on measures and therapeutic alliance did not approach significance, observable trends show CBT and AAT may be beneficial in decreasing anxiety symptoms for some students. The nature of self-report data and the small number of participants were limitations of the study. Overall this study used comparison groups to show that therapy dogs are not a hindrance to therapy and may be beneficial for some students.</p><p>

<p> Thirty cross-bred steers (initial BW 375 &plusmn;37.2, replicate 1; and 535.0 &plusmn; 39.4 kg, replicate 2) were utilized to investigate the effects of Mo water concentration on performance, carcass characteristics, and mineral status of feedlot steers fed a growing and finishing diet for 151 and 112 d for replicate 1 and replicate 2, respectively. The experimental design was a randomized complete block design. Steers were blocked by weight and then divided into 2 weight block replicates each consisting of 15 steers. Steers were randomly assigned within block to one of 5 treatments (3 pens/treatment; 1 steer/ pen; 2 replicates/treatment). Water treatments consisted of: 1) 0.0 &mu;g, 2) 160 &mu;g, 3) 320 &mu;g 4) 480 &mu;g Mo/L, and 5) 960 &mu;g of supplemental Mo/L added as Na₂MoO₄ to the drinking water. Steers were housed in individual pens that contained individual 265 L water tanks for monitoring water intake. Daily water intake was recorded for each steer. Steers were individually weighed on 2 consecutive days at the beginning and end of the experiment and interim weights and jugular blood samples were obtained every 28 d. Liver biopsies were obtained on d0 and 84 from each steers. Steers were transported to a commercial abattoir, slaughtered, and individual carcass data and liver samples were collected. Initial BW was used as a covariate for statistical analysis of the data and significance was determined at <i>P</i> &le; 0.05. No differences were observed for final BW (<i>P</i> &le; 0.98). Overall ADG, DMI, feed efficiency and water intake were similar across treatments. Hot carcass weight, dressing percentage, yield grade, LMA, adjusted fat thickness, KPH, and marbling scores were similar across treatments. Liver and plasma Cu, Mo, and Zn concentrations were similar across treatments. These data indicate that water Mo concentration had no impact on performance, mineral status, water intake, and carcass characteristics in feedlot steers fed a high concentrate diet.</p>