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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Effects of feeding regime on lamb flavour

Parry, Doreen January 1984 (has links)
Following reports that grazing lucerne and rape had produced flavour defects in lamb, the aim of this study was to determine if any of the fattening regimes for store lambs in the ESCA trials of 1977 produced unacceptable aroma or flavour in roasted gigots and loins. Careful studies of factors influencing meat flavour were made so that standardised procedures would ensure that feeding regime was the only variable in the trials. Hedonic rating scales were first used to determine optimal internal temperature for gigots and loins. Tasters at QMC and ESCA found difficulty in distinguishing samples cooked to different internal temperatures. Responses were inconsistent in duplicated trials. It was thus considered prudent to devise more precise assessment techniques for future studies. Triangle tests and paired comparison (preference) tests were subsequently used. In the first comparisons of grass and rape fed samples, there were no detectable differences in aroma or flavour. There was no consistent preference for either sample. Flavour profiles confirmed that neither feeding regime produced characteristic aroma or flavour. Tasters' performance was assessed. Results of these assessments indicated that the second series of comparisons of grass and rape and comparisons of the other forage crops could be carried out with greater confidence in both the experimental design and tasters' performance. None of the fattening regimes for store lambs produced detectable differences in aroma or flavour. There was no consistent preference for the flavour of lamb from any of the feeding regimes although there was some evidence that feeding cabbage produces flavour which is very well liked. There was no difference in the a b ility ofjudges to identify the odd sample in triangle tests when the aroma of raw and cooked samples was compared. This finding has considerable implications for future experiments. The contribution of fatty tissue to flavour was studied. Total and evaporative weight losses and raw and cooked pH values of gigots and loins were recorded. Statistically significant differences were established between the two cuts although pH changes in response to the cooking process did not differ. These findings emphasise the importance of comparing meats of standard anatomical location. An account of the basis on which the sensory tests used in the trials were selected is given together with details of statistical techniques used in the analysis of data.
272

Effect of sub-clinical parasitism on the absorption of nutrients from the gastro-intestinal tract of sheep, with special reference to calcium and phosphorus

Wilson, Wilma Duncan January 1982 (has links)
Recent studies have established that abomasal and intestinal parasitic infections can reduce the growth and mineralisation of the skeleton of growing lambs. One possible cause for the skeletal effect is that the parasites induce a mineral deficiency by reducing the absorption of dietary Ca and P and/or increasing the endogenous loss of these two elements. The importance of these factors was investigated in this study, This was achieved by using growing lambs fitted with cannulae in the rumen, abomasum and ileum and infected daily with Trichostrongylus colubriformis larvae,Ostertagia circumcincta larvae or no larvae. The lambs were fed the complete diet Ruminant A and the flow rates were measured by reference to soluble and particulate radioactive markers. The endogenous fraction of Ca and P in faeces and digesta was measured by the method of isotope dilution involving a single intravenous dose of 32P and 45Ca. A preliminary investigation showed that the best method for calculating the fraction of Ca and p which is of endogenous origin was the area method using a two day delay and that the SR in plasma was more reliable than the SR in urine, 0. circumcincta infection was without effect on the absorption and secretion of Ca and p in the digestive tract, other than producing a small but significant increase in the endogenous faecal Ca excretion. There was, however, a striking increase in the flow of digesta at the abomasum,the DM and Ka content of which was consistent with an increased secretion from the mucus - type cells in the abomasal mucosa. The extra digesta was absorbed in the small intestine, T, colubriformis infections reduced the absorption of exogenous p by about 30% and increased losses of endogenous P due to the action of worms on the mucosa of the small intestine. The net effect of this v;as to induce a P deficiency in TC lambs leading to a reduced flow of salivary P and a reduction in the plasma concentrations of p. The effect of T, colubriformis on Ca metabolism was limited to an increase in endogenous faecal excretion.
273

The development of behaviour patterns and an assessment of temperament of dairy heifers

Dennison, Sheila Ganson Copley January 1985 (has links)
The main aims of this study were 1) to describe the development of behavioural patterns in dairy heifers, 2) to investigate individual differences in behaviour and temperament, 3) to assess the temperament of each during milking and 4) to determine whether measures of early behaviour are related to temperament at a later age or to production measurements. Time based focal animal samples of twenty Friesian heifer calves over a period of two years recorded the activity of the calf and its nearest neighbour. A study of beef suckler calves reared with their dams was available for comparison of early development. The animals reactivity to being touched was tested approximately weekly and its temperament during milking was assessed. Data on liveweight measurements and daily milk yields were available. Development of the heifer's behavioural activities is shown graphically, either as proportion of time spent or frequency of occurrence. The development is considered in two ways 1)development in relation to chronological age, and ?_)development in relation to period of time within a particular rearing condition. However, the development was similar in both cases. Testing of the mean values of the activities for each separate rearing condition, normally experienced by dairy calves during their rearing, showed significant changes. Diagrams of significant sequential changes of activities show the development of the context of these behavioural actions. These results are compared with those obtained for field calves to indicate where environmental conditions may be affecting the development of the dairy calves behaviour patterns. The animals were then considered individually. Individual differences in the proportion of time spent in different activities was not consistent in each rearing period. The heifers social profile is represented by histograms of the frequency of expression of two categories of social behaviour, social licking and aggression. Associations between heifers, measured as the most time spent as its nearest neighbour, was only observed between a pair of twins. The reactivity of the heifers to being touched showed that most of the heifers were consistent in their reaction from an early age. Investigation of position within the herd and ease of entry to the parlour during the milking routine showed that heifers were recorded more often in the in the last third of milking group which was also associated with being pushed into the parlour by the dairyman. investigation of correlation between the behavioural measurements and between the behavioural and production measurements (i.e. growth rate of the heifers and the mean daily milk yield) is discussed. For the behavioural measurements, only the correlation between the frequency of initiating aggression and milking temperament was significant at p < 0.05 level. However, three other correlations approached significance i.e. correlation of proportion of time spent passively as a calf with frequency of initiating aggression, frequency of initiating social licking with proportion of times pushed into parlour and proportion of times pushed into parlour with milking temperament. This led to the hypothesis of a trend in the development of behaviour characteristics of dairy heifers. There appeared to be little relationship between the behavioural measures of the heifers and measures of their productivity with only the correlation between frequency of initiating social licking and mean daily milk yield reaching the p < 0.05 level of significance. Finally, a discussion of these findings in relation to theories of development(e.g. effect of environment, early experiences) and their implications for animal husbandry is presented.
274

The behavioural need for lying and feeding in the high yielding dairy cow

Cooper, Marc Damien January 2003 (has links)
Experiments were conducted to examine the impact of high milk yields on the behaviour and welfare of dairy cows. A preliminary study determined the social interactions existing within a group of 60 cows from which sub-samples of 20 high and 20 low yielding cows, that were not observed to interact with each other, were identified. These cows were used to examine the behavioural strategies employed by dairy cows coping with increased nutritional demands from milk production. Grazing time significantly increased with milk yield, consequently reducing lying time. A second study measured the appetite of high and low yielding cows for concentrates, using operant conditioning. The high yielding cows demonstrated no greater appetite for concentrates, but post-testing behavioural observations indicated greater appetite for forage, suggesting increased motivation to feed. Subsequent experiments investigated the behavioural effects of lying deprivation on dairy cattle welfare, further examining the feeding-lying conflict. Cows forced to stand had reduced milk yields and demonstrated behavioural signs of fatigue, frustration and stress, which were cumulative. When deprived of lying, a post-deprivation increase in this activity was achieved by reducing feeding time. When deprived of both lying and feeding, a feeding, not lying, post-deprivation increase was observed. However, lying was not reduced to extend feeding time. In conclusion, the motivation to feed was greater in high yielding dairy cows. This resulted in extended grazing and a reduced lying time. Lying can be regarded as an important and highly motivated behaviour and may compromise welfare if reduced. The legitimacy of using individual dairy cows as replicates in the statistical analysis of their behaviour was also investigated. There was no significant difference in the coefficients of variation between cows that were free to interact, and those that were not, for a range of behaviours. Therefore, those cows able to interact did not appear to influence each other's behaviour, supporting the use of individual dairy cows as replicates.
275

Troeteldier gefasiliteerde post traumatiese terapie deur die opvoedkundige sielkundige / Pet facilitated post traumatic therapy by the educational psychologist

Krüger, Deirdré 06 1900 (has links)
Text in Afrikaans / Hierdie studie handel oor die ontwerp van 'n post traumatiese terapie deur die opvoedkundige sielkundige waar troeteldiere as fasiliteerder ingespan kan word. Dit fokus op getraumatiseerdes wat na afloop van 'n trauma in 'n post traumatiese situasie verkeer, en nie klinies aan die diagnose van post traumatiese stres versteuring voldoen nie. Die ontwerp van die terapie val in vier fases uiteen wat nie noodwendig streng chronologies in terapie hoef te verloop nie. Eerstens is daar die affektiewe fase wat handel oor die bantering van emosies. Tweedens fokus die kognitiewe fase op kognitiewe herstrukturering by die getraumatiseerde en veral die internalisering daarvan. Die fase van voorraadopname maak voorsiening vir die identifisering van psigologiese gestremdhede en sterker modaliteite van die getraumatiseerde. Die kompensatoriese fase handel oor die ontwerp van 'n aksieplan vir die sinvolle voortsetting van die getraumatiseerde se lewe asook inoefeningsaspekte daarvan. Die terapeutiese ontwerp het beslag gekry na 'n uitgebreide literatuurstudie van verskeie terapeutiese skole se post traumatiese terapiee en tegnieke. Oorhoofs word bogenoemde ontwerp in die relasieterapie ingebed. Hierdie terapie le besondere klem op die kompensatoriese fase met die oog op adekwate aktualisering van die getraumatiseerde in sy toekomstige gesitueerdheid. Alhoewel daar 'n uitgebreide beskrywing van troeteldier gefasiliteerde terapie volg, het die navorser slegs sekere getraumatiseerde kliente ge'identifiseer wat sat baat by troeteldier gefasiliteerde terapie. Daar is tydens die studie aandag gegee aan die ontwerp van 'n vraelys wat as operasionele metingsinstrument dien om die omvang van die trauma ten opsigte van die getraumatiseerde se filnksionering, selfgesprekke, belewenis, betekenisgewing, betrokkenheid, seltkonsep, relasies en selfaktualisering te bepaal. Fasiliteerders van die affektiewe fase sluit onder andere soos reeds genoem hierbo, troeteldiere in. Ondersoek is ingestel na die riglyne vir troeteldier gefasiliteerde terapie, en verskeie aspekte soos determinante by die getraumatiseerde vir troeteldier gefasiliteerde terapie, die aard van mens-dier interaksie, risiko's en menslike voorwaardes verbonde aan troeteldier gefasiliteerde terapie, is beskryf Tydens die empiriese ondersoek is gevind dat alhoewel die ontwerp beperkinge het, daar besliste ruimte vir troeteldier gefasiliteerde post traumatiese terapie op Sielkundige Opvoedkunde terrein bestaan / This study deals with the design of a post traumatic therapy that can be administered by the educational psychologist. Pets were used for the first time as facilitators in such a therapy. This therapy was primarily designed for persons in a post traumatic situation after an experienced trauma, who _do not ~fy foc!h<L~!i_ni~_ctl _ cri!~!"ia gf post traumatic _stress disorder. Four phases can be distinguished in the course of the therapy. This doesn't however imply a hierargical order. First of all the affective phase deals with the emotional side of the traumatised person. Secondly cognitive restructuring is taken up in the cognitive phase as well as internalization thereof The third phase of stock taking makes provision for the identification of psychological handicaps and stronger modalities of the traumatised person. A plan of action is developed in the final compensatory phase and it deals with optimal future actualization of the traumatised person. If necessary, opportunity is provided for excercising the newly required skills. This design was developed after extensive literature studies of post traumatic therapies and techniques, and it is embedded in the overall approach of relationship therapy. Strong emphasis is placed on the compensatory phase in view of the traumatised person's adequate future actualization. Although an extensive description of pet fasilitated therapy is given, only certain traumatised clients were identified who will benefit from this therapy. A questionnaire as operational measuring instrument was developed for the purpose of this study. Information as to the traumatised person's functioning, selftalk, experiences, allocation of meaning, involvement, selfconcept, relationship formation and selfactualization can be ascertained via this instrument. One of the facilitators of the affective phase, already mentioned, includes pets. A thorough study into guidelines for pet facilitated therapy, as well as aspects such as determinants of traumatised people as indication for this kind of therapy, the nature of human-animal interaction, risks and human conditions for pet facilitated therapy, was undertaken. The empirical study proved that in spite of limitations of pet facilitated post traumatic therapy, definite opportunity exists in the field of Psychology of Education for this kind of therapy / D.Ed. (Sielkundige Opvoedkunde)
276

The application of recently developed techniques to Welsh Black Cattle in a group breeding scheme

Brown, Christopher Mark January 1990 (has links)
Methods of superovulation, embryo recovery and embryo transfer were adapted and developed for application to Welsh Black cattle in a Group Breeding scheme. Three methods of oestrus detection in early postpartum suckling beef cows were evaluated. None was entirely reliable although a probe for the measurement of the electrical resistance of vaginal mucus was the most effective and the least stressful. The postpartum interval to superovulation did not affect the responses to treatment. The effect of suckling on embryo quality from superovulated Welsh Black cows was investigated. Three groups of cows (one dry and two suckling) were superovulated and their embryos recovered in two seasons; summer and autumn. Significant effects of season (P=O.016) and suckling (P=O.015) on embryo quality were detected. Season significantly affected the number of viable embryos (P=O.004). There were no effects on ovarian responses or on the numbers of embryos recovered. Nutritional supplementation and the administration of heG failed to improve embryo quality. Examination of the data from three years of superovulation and embryo recovery revealed significant monthly variations in % viable embryos (P=O.006) and in the numbers of viable embryos (P=O.02) recovered. Embryo recovery was not affected by the catheter used or by the side of uterus being flushed. The number of pari ties of the donor affected the ovulation rate (P=O.009) and the numbers of embryos recovered (P=O.028) but not the embryo recovery rate (%). No differences were detected in the superovulatory responses of cows bred by 3 methods nor from the method of oestrus synchronisation. Embryo transfers were performed by surgical and nonsurgical methods. Fresh and frozen embryos were successfully transferred by the surgical technique but no embryos transferred nonsurgically continued development. A measurement of cervical diameter was successful in identifying animals which were unsuitable for non-surgical embryo transfer and recovery procedures. n-Alkanes as nutritional markers for intake estimation were applied'to cattl~ in a performance test and to cows at pasture. The results obtained indicate that the method may be useful in the future development of selection methodologies for beef cattle. The findings of both series of investigations are discussed in relation to beef cattle improvement through Group Breeding schemes.
277

Some effects of furazolidone in poultry

Ali, Badreldin Hamid January 1981 (has links)
No description available.
278

Sheep and goat production in the north west province of Cameroon, with special reference to parasitic gastroenteritis

Ndamukong, Kenneth Jacob Ngoh January 1987 (has links)
No description available.
279

Uterine prostaglandins in the non-pregnant sheep : studies on release and lymphatic transport

Abdel Rahim, Sheik El Din Awad January 1983 (has links)
No description available.
280

Farelo de casca de milho sem água de maceração em alimentos completos para cães: digestibilidade aparente dos nutrientes, balanço hídrico e características físico-químicas das fezes / Corn gluten feed without steep water in complete food for dogs: nutrient digestibility, water balance and chemical-physical characteristics of faeces

Juliana de Melo Pires 28 June 2013 (has links)
O presente trabalho teve como objetivo estudar a viabilidade de inclusão de farelo de casca de milho sem água de maceração em substituição ao farelo de trigo no alimento completo para cães através de ensaios de digestibilidade e análises de características físico-químicas das fezes. Foram utilizados 24 cães da raça Beagle em delineamento inteiramente casualizado, alojados em gaiolas metabólicas e submetidos a tratamentos com diferentes níveis de substituição de farelo de trigo por farelo de casca de milho sem água de maceração nos seguintes níveis: 0; 30; 60 e 90 g/kg. Para avaliação dos resultados de escore fecal, utilizou-se o teste Kruskal-Wallis e, para os resultados de digestibilidade e demais características fecais foi utilizado modelo misto. Em caso de efeito significativo (p&lt;0,05) foi realizada a análise de regressão. Não foi observado efeito dos tratamentos (p&gt;0,05) sobre o coeficiente de digestibilidade de matéria seca, matéria orgânica, proteína bruta, extrato etéreo, fibra bruta, fibra em detergente neutro, fibra em detergente ácido, extrativo não nitrogenado e energia bruta, entretanto, houve efeito (p&lt;0,05) para energia digestível e para energia metabolizável. Para as características fecais foram observados efeitos (p&lt;0,05) dos tratamentos sobre a matéria seca e o pH. Não foi observado efeito (p&gt;0,05) para as demais características das fezes: excreção fecal diária, escore fecal, excreção de matéria natural a cada 100g de alimento ingerido, excreção de matéria seca a cada 100g de matéria seca de alimento ingerido, capacidade tamponante a pH 5, nitrogênio amoniacal e balanço hídrico. O farelo de casca sem água de maceração pode ser utilizado em até 90g/kg em substituição ao farelo de trigo, sem causar efeito deletério sobre a digestibilidade e características físico-químicas das fezes. / The present study aimed to investigate the feasibility of including corn gluten feed without steep water replacing the wheat bran in complete feed for dogs through digestibility and analyzes of physical and chemical fecal characteristics. It was used 24 Beagle dogs in a randomized design, housed in metabolic cages and subjected to treatments with different levels of substitution of wheat bran by corn gluten feed without steep water in the following levels: 0, 30, 60 and 90 g/kg. To evaluate the results of fecal score, we used the Kruskal-Wallis test, and the results of digestibility and the others fecal characteristics was used mixed model, in case of significant effect (p&lt;0.05) regression. There was no treatment effect (p&gt;0.05) on the digestibility of dry matter, organic matter, crude protein, ether extract, crude fiber, neutral detergent fiber, acid detergent fiber, non-extractive nitrogen and gross energy however there was effect (p&lt;0.05) for digestible energy and metabolizable energy. For the fecal characteristics were observed effects (p&lt;0.05) treatments for the dry matter and pH. There was no effect (p&gt;0.05) for the other fecal characteristics: daily fecal score, fecal excretion of natural matter every 100g of food intake, excretion of dry matter each 100g of dry food intake, buffering capacity at pH 5, ammonia nitrogen and water balance. The corn gluten feed without steep water can be used to replace up to 90g/kg wheat bran, without causing a deleterious effect on the digestibility and physical-chemical characteristics of feces.

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