The current modern commercial pig is an animal that has evolved through deliberate breeding programs, controlled environmental influences and nutrition to yield a highly efficient feed converter and fertile animal. The objective of this study was to measure the growth performances and carcass characteristics of entire male grower – finisher pigs which were subjected to different seasonal variations, nutrient dense diets, feeding regimes and group situations under South African circumstances. Period 1 was conducted in the winter from 6 June 2008 to 13 August 2008 and Period 2 in the summer from 3 October 2008 to 10 December 2008. The sire lines that were selected for the experiment had the same genetic breeding values (Topigs Selection Index value), of which two sire lines were the same in both Period 1 and Period 2 and one of two different sires lines was used either in Period 1 or Period 2. The animals were fed two different rations, a high (FH) and a low ration (FL), with the low ration’s specifications being 95 % of the high ration. The animals were randomly allocated three different feed regimes throughout the trial; restricted single feeding (RSF), ad libitum single feeding (ASF) and ad libitum group feeding (AGF). In the winter animals had a greater growth response compared to the summer, with end weight and average daily gain being significant (P<0.05) higher. A significant (P<0.05) improvement in average daily gain, feed efficiency and protein deposition rate were observed when animals were fed a higher energy and protein content in their diet, especially during summer. A significant (P<0.05) improved feed conversion was observed for restricted animals, but end weight, average daily gain and average protein deposition rates were significant (P<0.05) lower compared to ad libitum group and individually fed animals. In conclusion; the impact of decreasing the nutrient density of the diet for growing pigs through incremental changes in diet composition had a variable impact on overall growth performance and carcass quality. Feeding the high energy and protein ration improved growth performance during summer, but also in the initial stages of growth when feed intake capacity was limited. The objective when formulating diets should be to provide the essential amino acids and energy in amounts needed to support maximal and efficient growth. Using growth models estimated optimal feed intake curves will not deliver optimal results. Only when measuring and calculating the actual feed intake and protein deposition rates optimal performance levels will be reached. Measurements of feed intake and growth performance data derived from pigs penned individually should be adjusted before they can be applied to commercial situations or research conditions in which pigs are penned in groups. / Dissertation (MSc(Agric))--University of Pretoria, 2010. / Animal and Wildlife Sciences / unrestricted

No abstract available. / Thesis (DPhil)--University of Pretoria, 2011. / Biokinetics, Sport and Leisure Sciences / unrestricted

No abstract available. / Thesis (DSc(Agric))--University of Pretoria, 1975. / Production Animal Studies / unrestricted

The piece is a twenty minute work discoursing the integration and eventual dissolution of two separate musical strands. The pitch material of each strand is determined from synthetic scales whose intervalic content duplicates at the following intervals: Perfect 12th, Diminished 12th, Minor 9th, Perfect 8ve, and Major 7th. A proportional means of temporal compression is generated through the use of the factor, 11/15 (e.g. Event 2 is 11/15 the duration of Event 1). Various elements of jazz music informed the construction of plies, including the instrumentation of the ensemble and the means by which the performers interact throughout the piece. Internal cueing and performer decisions are meant to eliminate the need of a conductor in favor of increased interpretive freedom by the performers.

In der randomisierten, multizentrischen DASH-Studie (Dietary Approaches to Stop Hy-pertension), die unter kontrollierten Bedingungen stattfand, führte eine fettreduzierte Mischkost, reich an Obst, Gemüse und Milchprodukten, bei Borderline-Hypertonikern zu einer signifikanten Blutdrucksenkung. Während der Studienphase wurden Körpermasse, Natrium-Aufnahme sowie Alkoholzufuhr aufgrund der bekannten Einflussnahme auf den Blutdruck konstant gehalten. In der eigenen Pilot-Studie sollte untersucht werden, ob das Ergebnis der DASH-Studie (i) mit deutschen Hypertonikern und (ii) unter habituellen Ernährungs- und Lebensbedingungen mit regelmäßig durchgeführter Ernährungsberatung und ad libitum Verzehr anstelle des streng kontrollierten Studienansatzes bestätigt werden kann. Eine Konstanz der Körpermasse, der Natrium-Urinausscheidung (unter diesem Studienansatz valider als die Aufnahme) und des Alkoholkonsums wurde vorausgesetzt.<br /> Die Studienpopulation setzte sich aus 53 übergewichtigen Probanden mit einer nicht medikamentös therapierten Borderline-Hypertonie und ohne Stoffwechselerkrankungen zusammen. Die Studienteilnehmer wurden randomisiert entweder der Idealgruppe mit einer fettarmen Kost reich an Milchprodukten, Obst und Gemüse (ähnlich der DASH-Idealgruppe) oder der Kontrollgruppe mit habitueller Ernährungsweise zugeteilt. Über einen Zeitraum von fünf Wochen wurde den Probanden etwa 50% ihres täglichen Lebensmittelbedarfes entsprechend ihrer Gruppenzugehörigkeit kostenfrei zur Verfügung gestellt. Gelegenheitsblutdruckmessungen und 24h-Blutdruckmessungen, Ernährungs- und Aktivitätsprotokolle, Blut- und Urinproben sowie anthropometrische Messungen wurden vor, während und fünf Wochen nach der Interventionsphase durchgeführt.<br /> Die Ergebnisse zeigen, dass in der Idealgruppe keine signifikante Blutdrucksenkung beobachtet werden konnte. Dies lässt sich durch die Tatsache erklären, dass die Lebens-mittel- und Nährstoffaufnahme der deutschen Kontrollgruppe eher der amerikanischen Idealgruppe entsprach. In der Pilot-Studie waren die Unterschiede in der Nährstoffzufuhr zwischen den beiden Gruppen viel geringer als in der DASH-Studie; für eine blutdrucksenkende Ernährungsumstellung bestand somit nur ein geringer Spielraum. Eine weitere Erklärung besteht in der unterschiedlichen Zusammensetzung der Studienpopulation. Bei DASH wurden vorwiegend farbige Probanden (40% höhere Hypertonieprävalenz) untersucht. Die Studienergebnisse lassen also den Schluss zu, dass Ernährungs- und Lebensstilgewohnheiten sowie der genetische Hintergrund der entsprechenden Bevölkerungsgruppe bei der Formulierung von nährstoff- oder lebensmittelbezogenen Empfehlungen zur Senkung des Bluthochdruckes Berücksichtigung finden müssen. / The Dietary Approaches to Stop Hypertension trial (DASH), a randomized well-controlled feeding study conducted at 4 medical centers, demonstrated that a low-fat diet, rich in fruits, vegetables and dairy products is able to lower blood pressure of borderline-hypertensive people significantly. Body weight, sodium intake and alcohol consumption were kept constant during the whole study period, due to the known influence on hypertension. Aim of our study project was to investigate whether the results of the DASH study can be confirmed by (i) using a German hypertensive population and (ii) replacing the well-controlled feeding design by allowing ad libitum intake according to dietary ad-vice. The participants were asked to keep their body weight, sodium urine excretion (un-der this study design more valid than sodium intake) and their alcohol consumption con-stant.<br /> Our pilot study population consisted of 53 mainly overweight participants with borderline hypertension and without medication or any metabolic disorders. They were randomly assigned to either an ideal diet low in fat and rich in dairy products, fruits and vegetables (similar to the DASH I-group) or a habitual diet as control (C-group). During five weeks the subjects were provided 50 % of their daily intake for free according to their dietary pattern. Single and 24h-blood pressure measurements, dietary weighed and physical activity records, blood and urine samples and anthropometric measurements were collected before, during and five weeks after the intervention period.<br /> The study results indicated that no significantly reduction of blood pressure could be observed for both methods in the I-group of our trial. This is due to the fact that the baseline intake of foods and nutrients of the German subjects was nearly corresponding to the intake targeted for the DASH I-group. Therefore, it was impossible to increase the intake of these nutrients in our I-group by the same percentage as in the DASH study. Another explanation may be the different consistency of the study population. About 60% of the DASH study population were African Americans with a known higher prevalence of hy-pertension (about 40%) than Caucasians.<br /> The conclusion is that even convincing results of a controlled trial cannot be simply transferred into dietary advice for the general public. For addressing food-based dietary guidelines to reduce the risk of hypertension it is necessary to consider the genetic background as well as the dietary and the lifestyle situation of the target population carefully.

Zugl.: Giessen, Univ., Diss., 2003

As a contribution to the existing knowledge of grooming in primates five and a half years of grooming data were examined from a group of free-living chimpanzees (Pan troglodytes) in the Budongo Forest, Uganda, to investigate various functional significances of grooming behaviour within the context of social reinforcement. The fission–fusion social structure of chimpanzees results in group members not moving around as a single unit, but forming temporary units as the need arises. This reduces opportunities for individuals to groom others and therefore, based on time and association constraints alone, grooming was as expected found to be unevenly distributed among group members. Grooming patterns found among this group of chimpanzees were comparable to those observed in other free-living populations with variations possibly being attributed to resource base, population numbers and differences in age-sex class composition. One of the suggested social benefits of grooming is that it is used to enhance reproductive success, either by allowing males to enhance their proximity to oestrous females, or by influencing female choice through the development of affiliative relationships with males. Grooming was found to increase between males and females, whilst females displayed sexual receptivity through the presence of anogenital swellings and grooming may be a strategy used by males to increase their access to copulation opportunities, whereas females may use grooming to increase protection from harassment by less preferred males during swollen periods and also increase the likelihood of copulation with preferred partners. Based on the availability of oestrous females, copulations between males and adult females occurred significantly less frequently than expected, whereas copulations between males and subadult females occurred significantly more frequently than expected. Overall a positive correlation was found between grooming of females by males and frequency of copulations. Due to concerns regarding the validity of different sampling methods, scan-focal and ad libitum sampling methods were compared to establish if results from different sampling methods were similar. Results from the scan-focal and ad libitum sampling methods had very few discrepancies, and it is suggested that ad libitum sampling methods which record behaviour types whenever they occur, may be more beneficial for species which don’t move around as a single unit and live in environments where visibility is reduced, therefore increasing the possibility of recording individuals or behaviours that are observed infrequently. Scan-focal sampling may be more beneficial in studying species which move around together in habitats which are conducive to greater visibility, therefore allowing all or most group members to be observed simultaneously. / Thesis (DPhil)--University of Pretoria, 2009. / Zoology and Entomology / unrestricted

Background Extensively used grasslands are frequently utilised for hay production for equines. Especially, extensive meadows have a great variety of plant species, which may include plants that are poisonous for equines such as meadow saffron (Colchicum autumnale L.). To authors’ knowledge investigations about horses` avoidance behaviour towards dried meadow saffron in hay are missing. Reports of farmers are contrary to clinical symptoms described in case reports and associated with meadow saffron in hay. Objectives The aim of this study was to determine the rejection behaviour of horses for hay contaminated with meadow saffron (MS) when fed ad libitum. Study design An 18-day feeding trial with six adult geldings to observe the rejection behaviour for hay contaminated with MS. Methods The horses were fed a basal diet containing hay ad libitum and a mineral supplement during the feeding trial. At six different daytimes, hay contaminated with 1% or 2% dried MS was provided to the horses over a duration of 1 h. The rejection behaviour was observed personally and by video recordings. If a horse ingested more than two plants of MS during one observation period, the observation was stopped and repeated at another day. When the observation period had to be stopped twice, the horse was excluded from the experiment. Results Five of six horses ingested MS during the first feeding periods. One horse rejected leaves and capsules at the beginning of the study, but it showed repeated ingestion of MS after the seventh observation period. Main limitations Lack of knowledge about secondary plant metabolites affecting taste and their variability between fresh and dried plants. Conclusions The intake of MS in hay by horses could not be ruled out with certainty. Therefore, feeding hay contaminated with MS should be avoided for equids.

Philosophiae Doctor - PhD / Introduction: Plant extracts and herbal preparations are often marketed as natural and safe alternatives to conventional medicines for the prevention and treatment of a variety of ailments, without proof of efficacy and safety. Cardiovascular, hematopoetic, hepatic and renal impairment resulting from the use of conventional drugs is widely acknowledged. However, there is less awareness of the potential toxicity of herbal preparations and other botanicals, many of which are widely perceived by the public as being effective and harmless, and are commonly used for self medication without supervision. In addition, potential interactions between herbal medicines and conventional drugs may compromise with patient management. In the safety evaluation of most substances, non human primates are preferred to rodent species for preclinical animal safety studies, because of their biological similarity to humans. They are regarded to be the best metabolic models for humans in a broad range of investigations. Additionally, a disadvantage of using small animal species in toxicological testing is that they require higher doses of drugs and more frequent administrations than in larger species. In light of these considerations, vervet monkeys are used here to investigate toxicity of a plant-derived triterpene, oleanolic acid. The focus is to determine effects of different concentrations of this triterpene on the cardiovascular, hematopoetic, hepatic and renal systems. Materials and methods: 12 male vervet monkeys used in this study were equally divided into four groups, i.e. three treatment groups (4, 10 and 25 mg/kg bodyweight), and one control group. Each individual in a treatment group received a specified concentration of oleanolic acid in food for 16 weeks. Monkeys in the control group received the vehicle (food) alone. Bodyweight, body temperature, respiratory rate, heart rate, systolic pressure, diastolic pressure, and mean arterial pressure were recorded from ketamine-anaethetized monkeys at baseline and every second week until week 16. In addition, blood samples were collected at baseline and every fourth week for clinical biochemistry indicators (serum electrolytes, enzymes, proteins, lipids, nitrogenous compounds, bilirubins and glucose) and hematological tests (red cell count and its indices, hemoglobin, haematocrit, white blood cell and differential count and platelet count). Results: No animal showed deviation from their normal behavioral patterns, food and water intake, was in poor health or died during and after completion of the study. The average bodyweights were not statistically significantly different between controls and the treated groups. The biphasic changes in the average body temperature of treated monkeys were similar to those seen in the control group during the first eight weeks of the study. No statistically significant differences were found in body temperature determinations between controls and the treated groups. Fluctuations observed in the respiratory rates of the treated monkeys were not statistically significantly different from that of the control group. Although not statistically significantly different from the controls, the systolic, diastolic and mean arterial pressures in the group treated with 25 mg/kg oleanolic acid were lower at week 16 compared to baseline, while those of the groups treated with 4 and 10 mg/kg oleanolic acid were relatively unchanged. Except for a reduction in systolic pressure of the control group, other blood pressure parameters were stable. Heart rates in the treated groups were not statistically significantly different from those in the controls. In all groups, except the control, high density lipoprotein concentrations were higher at week 16 compared to baseline. Fluctuations in low-density lipoprotein and total cholesterol concentrations were similar between controls and the treated groups. The triglycerides were lower at week 16 compared to baseline for all four groups. Upward trends from baseline to the end of the study were observed in creatine kinase concentrations of the controls and the groups that received 4 and 25 mg/kg. Concentrations of this enzyme were unchanged in the group that received 10 mg/kg oleanolic acid between baseline and the end of the study. No statistically significant differences were found with cholesterol, triglyceride and creatine kinase concentrations between treated groups and the controls. Serum concentrations of aspartate aminotransferase were unchanged in the controls and the groups treated with 4 and 10 mg/kg oleanolic acid, but changes in this parameter over time were statistically significantly different (P = 0.0452) from the controls in the group that received 25 mg/kg oleanolic acid. Despite wide fluctuations in the alanine aminotransferase concentrations in the groups that received 4 and 25 mg/kg oleanolic acid, no statistically significant differences were found with any of the treated groups compared to the controls. No statistically significantly different changes were seen in alkaline phosphatase activities between controls and the treated groups. Reductions in gamma-glutamyl transferase activities in the groups that received 4 and 25 mg/kg oleanolic acid were not statistically significantly different from concentrations of this enzyme in the controls. In addition, no statistically significant differences were evident between controls and the group that received 10 mg/kg oleanolic acid. There were no statistically significantly different changes in the total and conjugated bilirubin and glucose concentrations between controls and the treated groups. Fluctuations over time in the serum albumin and globulin concentrations were similar between treated groups and the controls, whereas total protein concentrations were relatively constant. Consequently, no statistically significant differences were found between controls and the treated groups. Wide fluctuations were observed in the creatinine concentrations of the groups that received 4 mg/kg oleanolic acid, while no such changes were encountered in the controls and the group that received 10 and 25 mg/kg oleanolic acid. Serum urea concentrations increased in all groups over time, except for the group that received 10 mg/kg oleanolic acid. Both urea and creatinine concentrations in the treated groups were not statistically significantly different from concentrations in the controls. Serum concentrations of sodium, chloride, potassium, calcium and magnesium and phosphate in the treated groups were not statistically significantly different from these electrolyte concentrations in the controls. Decline in red cell and hemoglobin concentrations of the controls and the group that received 25 mg/kg oleanolic acid were not statistically significantly different between these groups. In addition, no statistical significant differences were found in red cell and hemoglobin concentrations between controls and the groups that received 4 and 10 mg/kg oleanolic acid. Controls and the treated groups showed upward trends in haematocrit concentrations. Mean corpuscular volumes were statistically significantly increased; P = 0.0027 (4 mg/kg), P = 0.0010 (10 mg/kg), and P = 0.0022 (25 mg/kg), while mean corpuscular hemoglobin concentrations were statistically significantly reduced; P = 0.0017 (4 mg/kg), P = 0.0004 (10 mg/kg), P = 0.0002 (25 mg/kg) in the treated groups as compared to the controls. No statistically significant differences were evident in the concentrations of mean corpuscular hemoglobin between controls and the treated groups. White blood cell counts of the treated groups were not statistically significantly different from those of the controls throughout the study period. No statistically significant differences were found in the differential white cells and platelet counts between treated groups and the controls. Discussions: The results of this study showed that administration of oleanolic acid had no effects on the general wellbeing, bodyweights, body temperature, respiratory and heart rates, and blood pressure of vervet monkeys. A statistically significant increase in the aspartate aminotransferase activity of the group treated with 25 mg/kg oleanolic acid, together with the increase in the alanine aminotransferase levels during the same time period, might indicate oleanolic acid-induced hypersensitivity, and accordingly hepatocellular alteration. However, since serum concentrations of these enzymes returned to baseline levels, as well as the absence of variations over time in other parameters of the hepatic function, particularly alkaline phosphatase activity, it is likely that there was no underlying subacute liver disease. Serum renal function parameters also appeared to be within normal physiological limits. No pronounced changes were observed in the hematological parameters of monkeys that received oleanolic acid. Conclusion: This study's results, suggest that oleanolic acid does not produce cumulative liver enzyme alterations, and has no detrimental effects on the renal, hematopoetic and cardiovascular systems of vervet monkeys.

Einleitung: Aufgrund der Heuknappheit der letzten Jahre werden zunehmend auch extensiv bewirtschaftete Wiesen für die Heuproduktion genutzt. Teil der artenreichen Wiesen ist jedoch auch das Vorkommen von potentiell toxischen Pflanzen wie die Herbst-Zeitlose. Inwieweit Pferde getrocknete Herbst-Zeitlose im Heu erkennen und meiden, ist unzureichend erforscht. Erfahrungsberichte von Landwirten sowie Fallberichte kommen zu widersprüchlichen Ergebnissen. Ziele der Untersuchungen: Das Ziel der vorliegenden Untersuchung bestand in der Beschreibung des Selektionsverhaltens von Pferden bei Vorlage von Heu, welches mit Herbst-Zeitlosen kontaminiert war. Tiere, Material und Methoden: Die Studie (TVV-Nummer 17/19) wurde mit sechs klinisch gesunden, adulten (Alter: 11 – 17 Jahre) Warmblutwallachen (durchschnittliches Körpergewicht (KGW) ± Standardabweichung (SD): 674 ± 85 kg) durchgeführt. Die Pferde wurden in Einzelboxen auf Stroh mit täglichem Zugang zu einem Paddock gehalten. Heu wurde, mit Ausnahme der Aufenthaltszeit auf dem Paddock, ad libitum zur Verfügung gestellt und durch 50 g eines kommerziellen Mineralfuttermittels (Hoeveler, Reformin Plus©) ergänzt. Leitungswasser war zu jeder Zeit frei verfügbar. Jedes Pferd erhielt zu unterschiedlichen Tageszeiten über eine Stunde Heu, welches mit 1 oder 2 % getrockneten Herbst-Zeitlosen kontaminiert war. Das Selektionsverhalten der Tiere wurde individuell beobachtet, protokolliert und ausgewählte Beobachtungsperioden mittels Videoaufnahmen aufgezeichnet. Um Intoxikationen zu vermeiden, wurden Abbruchkriterien definiert. Nahm ein Pferd zwei Herbst-Zeitlose auf, wurde die Beobachtungsperiode abgebrochen und das kontaminierte Heu entfernt. Die Beobachtungsperiode wurde an einem anderen Tag und zu einer anderen Tageszeit wiederholt. Musste die Beobachtungsperiode erneut abgebrochen werden, wurde das entsprechende Pferd aus dem Versuch ausgeschlossen. Alle Pferde wurden zu Beginn des Versuchs und anschließend alle zwei bis drei Tage allgemein klinisch untersucht (Herz- und Atemfrequenz, Beschaffenheit der Schleimhäute, Darmgeräusche, innere Körpertemperatur, Pulsation der Gliedmaßen). Ein Blutbild sowie biochemische Blutuntersuchungen aller Pferde wurden zu Beginn und am Ende der Studie durchgeführt. Sowohl das gefütterte Heu als auch die Herbst-Zeitlosen wurden auf die Menge ihrer Rohnährstoffe und Anteile der Faserfraktionen untersucht. Eine Messung der Colchicingehalte in den getrockneten Herbst-Zeitlosen wurde durchgeführt (Flüssigkeitschromatographie/Tandem-Massenspektrometrie). Die Ergebnisse der genannten Analysen wurden mithilfe von Microsoft Excel 2016® deskriptiv und mittels SPSS 27® statistisch ausgewertet. Ergebnisse: Keines der Pferde mied die Herbst-Zeitlose im Heu. Vier von sechs Pferden zeigten sogar eine Präferenz für die Pflanze und nahmen sie gezielt ohne umliegendes Heu auf. Lediglich ein Pferd mied die Herbst-Zeitlose während der ersten sechs Beobachtungsperioden. Innerhalb der siebten Beobachtungsperiode nahm es Anteile der Herbst-Zeitlose auf. Die Parameter der klinischen Untersuchung und die Blutwerte lagen zu jeder Zeit im physiologischen Normbereich. Bei der Messung der Rohnährstoffe konnten in der Herbst-Zeitlosen höhere Rohprotein- (CP: 12,5 ± 0,717 %) und Rohfettgehalte (CFAT: 3,86 ± 0,254 %), sowie ein höherer Anteil an stickstofffreien Extraktstoffen (NFE: 52,3 ± 1,24 %) als im Heu (CP: 7,84 ± 1,47 %; CFAT: 0,80 ± 0,237 %; NFE: 41,4 ± 1,99 %) nachgewiesen werden. Die Faserfraktion der Herbst-Zeitlosen (CF: 17,3 ± 0,837 %) stellte sich geringer als im Heu (CF: 34,5 ± 1,85 %) dar. Es wurde ein durchschnittlicher Colchicingehalt von 331 µg/g Trockensubstanz in der getrockneten Herbst-Zeitlosen gemessen. Schlussfolgerungen: Aufgrund der unselektiven, teils gezielten Aufnahme der Herbst-Zeitlosen durch die Pferde der vorliegenden Studie, sowie das stark gehäufte, nestartige Vorkommen der Herbst-Zeitlosen im Heu, können Vergiftungen durch kontaminiertes Heu nicht ausgeschlossen werden. Daher sollten Wiesen, auf welchen Herbst-Zeitlose wachsen, von der Heugewinnung ausgeschlossen werden.