Objectives were to characterize residual feed intake (RFI) and determine the phenotypic correlation between performance, feed efficiency, and other biological measurements in Brahman heifers, as well as the relationship between RFI determined in confinement and measurements of grazing activity on pasture. Three separate 70 d feeding trials were performed, and RFI was determined as the residual between actual and predicted dry matter intake (DMI) for a given level of production. Brahman heifers (n = 103; 5-to-9 mo of age) were individually limit-fed a pelleted 12% CP complete ration daily in Calan gates. Weekly body weight (BW) and DMI data were collected, and predicted DMI was determined by linear regression of actual DMI on mid-test metabolic BW. Ytterbium chloride was used to evaluate digestive kinetics, and fecal samples were collected to determine fecal volatile fatty acids (VFA) concentration and determine apparent dry matter digestibility (DMD) utilizing acid insoluble ash as an internal marker. Measurements of temperament were evaluated on all heifers at weaning. High (n = 6) and low (n = 6) RFI heifers (Exp. I) grazed fescue and ryegrass to determine variation in grazing behavior, DMI, and apparent DMD. Data from all three experiments were pooled, and RFI was not correlated with average daily gain (ADG), DMI, BW, partial efficiency of gain, feed conversion ration, fecal VFA concentration, or any measures of temperament. There were no significant differences in digestive kinetics between the RFI efficiency groups. Fecal samples taken for acid detergent insoluble ash (ADIA) determination were not collected at frequent enough intervals to account for weekly variation in fecal ADIA concentration. Pasture measurements were not different between the efficiency groups for heifers evaluated for grazing behavior, as well as estimated intake as a proportion of BW, or apparent DMD. Results of this study suggest that Bos indicus cattle appear to have similar efficiency traits as Bos taurus and Bos indicus influenced cattle, making this measure of efficiency equally as valid for use in both types of cattle. This indicates that selection based on RFI can be made to increase feed efficiency without affecting ADG or BW in Brahman cattle.

Thesis (Ph. D.)--University of Hong Kong, 2010. / Includes bibliographical references (p. 255-276). Also available in print.

Transition to parenthood is a major life event that affects both fathers and mothers. Being a potentially stressful period, it can predispose vulnerable individuals to mental health problems. Compared with maternal studies, there is a dearth of longitudinal research on the psychological impact of transition to fatherhood, particularly with anxiety problems. There are emerging studies demonstrating the adverse consequences of paternal postpartum depression on infant outcomes. It is important to investigate paternal postpartum depression and anxiety and address their relationships with poor infant outcomes which will contribute to the recognition of the problems and the development of early intervention. The current study aimed to contribute to greater knowledge on risk factors of paternal postpartum mental health problems, and their adverse impact on infants, as well as understanding the possible mediating mechanisms underlying such a relationship. A total of 654 couples completed self-report questionnaires at third trimester of pregnancy using validated self-report psychological instruments to evaluate fathers' prenatal mental health. Among them, 255 couples were examined longitudinally at six week postpartum for depression and anxiety symptoms, and fathers were also assessed for marital satisfaction, self-esteem, social support, and postpartum attachment with infants. At six months postpartum, 121couples were again surveyed to assess their infants’ temperament and development. According to established cut-offs, 12.0% and 13.1% of fathers experienced significant postpartum depression and anxiety. No demographic risk factors were found for postpartum depression or anxiety. Multiple regression analyses indicated that low martial satisfaction, low self-esteem, fathers having prenatal anxiety and depression, partners having postpartum depression predicted fathers’ postpartum depression. Low marital satisfaction, low self-esteem, poor social support and fathers having prenatal anxiety were significant risk factors for fathers’ postpartum anxiety. Depressed and anxious fathers reported having less patience and tolerance, pleasure in interaction, and affection and pride with their infants. Paternal postpartum depression was related to reduced infants’ falling reactivity, and poor social and total development in infants; while postpartum anxiety was associated with heightened infants’ distress to limitations, reduced failing reactivity and greater sadness. Baron and Kenny’s criteria was used to investigate whether poor paternal attachment with infants mediated these relationships. Pleasure in interaction partially mediated the relationship between paternal postpartum depression and social as well as total development in infants, whereas affection and pride mediated between fathers' postpartum depression and infants' falling reactivity as well as social development. Affection and pride also served as a partial mediator between fathers' postpartum anxiety and infants’ failing reactivity. Findings revealed that paternal postpartum depression and anxiety are significant mental health problems. Low marital satisfaction, low self-esteem, poor social support, prenatal depression and anxiety, and partners' postpartum depression could contribute to these problems. Postpartum depression and anxiety could reduce fathers' attachment with infants, which adversely impacted infants' temperament and development. The current study also addressed that risk factors for paternal postpartum depression and anxiety were different, and they had distinctive environmental pathways affecting infant outcomes. This provides significant implications for designing timely and effective interventions to improve fathers' well-being and proper father-infant interaction. (499 / published_or_final_version / Psychiatry / Master / Master of Philosophy

Domestication has resulted in animals with broad variations between as well as within breeds, which allows for the selection and breeding of animals for preferred traits. This selection has affected both the genotypes and phenotypes of animals. In dogs, it has allowed for breeding for different purposes, such as companionship or the performance of specific tasks, e.g., herding, hunting, searching and protecting. Each of these types of working dogs has specific traits that are, in part, controlled by genes; however, genes are not solely responsible for the variations in the traits of an individual. The environment also plays a role, which has been studied in rodents and primates in recent decades. For instance, it has been shown that the amount of maternal care that a rat receives as a pup affects its temperament later in life; the more maternal care, i.e., licking, grooming and arched-back nursing (LG-ABN), that a rat receives, the more stress resistant, less reactive and more explorative it will be as an adult. However, the question is whether this is also true for dogs, and the investigation of how temperament in dogs is affected by environmental factors early in life is the main objective of this thesis. Three of the studies presented in this thesis focused on investigating the general parameters, particularly maternal care, that influences offspring behaviour to contribute to the understanding of temperament development in military working dogs. One of these studies concentrated on the environmental factors that influence dogs early in life, and the results indicated that some factors, such as parity, litter size and birth season, affect temperament later in life. Another study investigated how females take care of their young, and the results demonstrated that females consistently vary in their maternal style during the first three weeks postpartum and that this variation affects the temperament of the offspring. The third study focused on factors in the home environment, and the results showed that dogs approved through the evaluative temperament test were significantly associated with being hyperactive or restless and having difficulty settling down in the home environment. However, those dogs were also left home alone for more hours in a day than non-approved dogs. To be able to operate functionally, a military working dog needs to possess certain traits, or a certain temperament, and a vital characteristic is the way it responds to and copes with stress. This was investigated during an evaluative temperament test used to select dogs suitable for further training. Surprisingly, the results showed that the dogs approved for further training had significantly higher levels of salivary cortisol both before and after the test compared with the non-approved dogs. These findings may be of profound importance for understanding individual variations in behaviour and improving breeding schemes for working dogs. / För över 15 000 år sedan började våra anfäder avla på vargar och lade då grunden för den uppsjö av olika hundraser vi ser idag. Exakt hur den här processen såg ut, när eller vart den startade vet vi faktiskt inte med säkerhet, men att vargen/hunden var det första djur att påbörja en sådan förändring, det vet vi. Att aktivt välja ut och avla på önskvärda egenskaper påverkar och förändrar gradvis djuret. Den här förändringen styrs i hög grad av gener, vilket medför att ett djurs s.k. genotyp förändras. Den här förändringsprocessen, där ett djur gradvis anpassas till ett liv som tamdjur, kallas för domesticering och innebär inte bara att djuret förändras genetiskt, utan också att den ändrar utseende och beteende, dvs. djurets fenotyp ändras också. Det är därför vi bl. a. ser så många olika hundraser som vi gör idag, allt från en liten hårlös Chihuahua till en stor raggig St. Bernard. Alla är de hundar, men de ser väldigt olika ut och har delvis olika egenskaper eller temperament. Det medför att de passar till att göra olika saker och därför också kan vara till stor nytta i samhället i allt från sällskapshunden som kan lära sig leta kantareller, till olika typer av tjänstehundar. Bra ledarhundar åt synskadade, polishundar som söker försvunna människor och narkotika, och försvarsmaktens tjänstehundar som kan förhindra angrepp eller terrorverksamhet genom att leta efter t ex. bomber och vapen - alla kan i förlängningen innebära ökad livskvalité och räddade människoliv. Men för det krävs att hunden passar för jobbet. Det är både generna, arvet och olika miljöfaktorer i den tidiga uppväxten som avgör egenskaperna hos en individ. Det är något som har visat sig gälla till exempel för råttor och primater. Studier på råttor har exempelvis pekat på att mängden omvårdnad en råtta får som liten (t ex hur mycket mamman slickar sina barn) påverkar dess egenskaper som vuxen. Och att ju mer omvårdnad de fått, desto mer stresståliga, mindre nervösa och mer nyfikna blev de. Även i studier på människor pekar resultaten i samma riktning. Men gäller detta även för våra hundar? För att öka kunskapen om och förståelsen för hur tidiga erfarenheter påverkar temperament, stress och arbetsförmåga hos våra blivande tjänstehundar i försvarsmakten har därför en rad olika studier på området genomförts. Den här avhandlingen fokuserar således på att undersöka vilka generella tidiga erfarenheter och faktorer i den tidiga uppväxtmiljön som tycks kunna vara med och påverka temperamentet hos våra tjänstehundar. Specifikt undersöker den hur tikens omvårdnad påverkar vissa egenskaper. Avhandlingen undersöker vidare hur stresståliga våra hundar är och hur detta yttrar sig i samband med de lämplighets test som hundarna genomgår i syfte att bedöma vilka individer som bör gå vidare till fortsatt träning efter ett och ett halvt års ålder. Resultaten i en studie visar att de hundar som bedömts som lämpliga vid lämplighetstestet något oväntat uppvisade ett högre påslag av stresshormonet kortisol, och i en annan studie att lämpliga hundar bedömts vara hyperaktiva/rastlösa och ha vissa svårigheter att ta det lugnt i hemmiljö. Detta samtidigt som de uppvisade en önskvärd temperamentsprofil vid uttagningsprovet, vilket kan antyda att dessa hundar är mer flexibla och motståndskraftiga mot stress, vilket skulle kunna vara resultatet av en lyckad avel. Vidare visade resultaten att det finns generella faktorer i den tidiga uppväxtmiljön, såsom tikens tidigare erfarenhet av att vara mamma, kullstorlek och när på året kullen föds, som är med och påverkar olika egenskaper. Den visar också att tikarnas sätt att ta hand om sina valpar varierade men var konsekvent under den första omvårdnadstiden på tre veckor och att det finns en koppling mellan mammans omvårdnads-stil och hur deras valpar blir som vuxna. Sammantaget visar avhandlingen att det finns faktorer i den tidiga uppväxtmiljön som påverkar temperamentet senare i livet på våra tjänstehundar. / <p>The ISBN <strong>987</strong>-91-7685-945-2 in the thesis is incorrect. Correct ISBN is <strong>978</strong>-91-7685-945-2.</p>

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Esta investigación se sitúa dentro de los planteamientos de la Psicología de la Personalidad que enfatiza las variables intrapersonales como determinantes de la satisfacción marital. La Personalidad normal o anormal, puede ser en parte, junto con otras variables, la causa de una relación de pareja satisfactoria o insatisfactoria. Se ha partido del supuesto de que la personalidad de cada uno de los miembros de la pareja contribuye de forma independiente a la Satisfacción Marital. El temperamento también es investigado, en tanto que contribuye a constituir factores o rasgos de personalidad, se analizan las relaciones existentes entre las dimensiones del temperamento y la satisfacción marital. El objetivo de la presente tesis es determinar de forma empírica si las variables del temperamento ( partiendo del modelo teórico de Thomas y Chess, 1977) se relacionan con la Satisfacción Marital. A su vez se investiga si las dimensiones del temperamento están relacionadas con la Conducta Sexual, ya que la Conducta Sexual mantiene relaciones significativas con la Satisfacción Marital. Un segundo objetivo de la investigación ha sido el analizar las relaciones existentes entre las dimensiones de Personalidad, Neuroticismo y Extraversión con la Satisfacción Marital y con la Conducta Sexual. Por último, también se ha analizado si el tiempo de casados y la edad de los miembros de la pareja mantienen alguna relación significativa con la Satisfacción Marital y con la Conducta Sexual. / We have investigated the relacionship between the dimensions of temperament (from Thomas & Chess theoretical model, 1977) and the marital satisfaction and sexual behaviour, in this doctoral thesis. At the same time, we have analysed what is the relationship which the variable of Personality, Neuroticism and Extroversion, holds whith marital satisfaction and sexual behavior. Finally, the relationship between the time of marriage and the age of the couple whith marital satisfaction and sexual behavior.

Adolescent participants (N=170) completed questionnaires assessing individual characteristics (gender, age, Sensation Seeking, Aggression/Oppositionality, Impulsivity) and characteristics of the neighbourhoods in which they live (Neighbourhood social cohesion/informal social control of youth). Postal codes as reported by the youth were linked to 2006 Canadian census data in order to determine area-level Socioeconomic Status (SES) for each adolescent. Data regarding adolescents’ individual traits and characteristics of the neighbourhoods in which they live were examined both as main effects and in individual by neighbourhood interactions as predictors of adolescents’ risk of injury. Individual traits predicted injury risk, however, neighbourhood social processes and SES did not predict adolescent injury risk when examined as main effects, whether included alone or together with individual characteristics. Neighbourhood social processes and Neighbourhood SES each moderated the relation between certain individual traits and injury risk. The value of examining individual-context interactions in injury risk research is discussed.

The objectives of this study were to 1) evaluate marker associations for genomic regions of interest and significant ontology terms, 2) evaluate and compare 4 models for their efficacy in predicting genetic merit, 3) evaluate and compare the impact of using breed-of-origin genotypes in a Bayesian prediction model, and 4) evaluate the effects of data partitioning using family structure on predictions. Nellore-Angus F2, F3 and half-sibling calves were used with records for overall temperament at weaning (OTW; a subjective scoring system; n = 769) and Warner-Bratzler shear force (WBSF; a measure of tenderness; n = 389). After filtering, 34,913 markers were available for use. Bayesian methods employed were BayesB (using ̂) and BayesC (using π = 0 and ̂) in GenSel software, where, after estimation, π ̂ = 0.995 or 0.997 for WBSF or OTW, respectively. No regions associated with either trait were found using π ̂, but when π = 0 associated regions were identified (37 and 147 regions for OTW and WBSF, respectively). Comparison of genomic estimated breeding values from these 3 Bayesian models to an animal model showed that BayesC procedures (using ̂) had the highest accuracy for both traits, but that BayesB had the lowest indication of bias in either case. Using a subset of the population (n = 440), genotypes based on the breed in which the alleles originated from (i.e., breed-of-origin genotypes) were assigned to markers mapped to autosomes (n = 34,449), and incorporated into prediction analyses using BayesB (π ̂ = 0.997) with or without nucleotide-based genotypes. In either case, there was an increase in accuracy when breed-of-origin genotypes were incorporated into prediction analyses. Data partitions based on family structure resulted in 13 distinct training and validations groups. Relationship of individuals in the training with validation individuals did have an impact in some cases, but not all. There was poor prediction of genomic estimated breeding values for individuals in the validation population using BayesB methods, but performed better in all cases than breeding values generated using an animal model. Future studies incorporating breed-of-origin genotypes are of interest to determine if accuracy is improved in these groups.

No description available.