title: Prediction of Oestrus in Dairy Cows: An Application of Machine Learning to Skewed Data

authors: Lynam, Adam David

subjects: machine learning

abstract: The Dairy industry requires accurate detection of oestrus(heat) in dairy cows to maximise output of the animals. Traditionally this is a process dependant on human observation and interpretation of the various signs of heat. Many areas of the dairy industry can be automated, however the detection of oestrus is an area that still requires human experts.
This thesis investigates the application of Machine Learning classification techniques, on dairy cow milking data provided by the Livestock Improvement Corporation, to predict oestrus. The usefulness of various ensemble learning algorithms such as Bagging and Boosting are explored as well as specific skewed data techniques.
An empirical study into the effectiveness of classifiers designed to target skewed data is included as a significant part of the investigation. Roughly Balanced Bagging and the novel Under Bagging classifiers are explored in considerable detail and found to perform quite favourably over the SMOTE technique for the datasets selected. This study uses non-dairy, commonplace, Machine Learning datasets; many of which are found in the UCI Machine Learning Repository.

text: Prediction of Oestrus in Dairy Cows: An Application of Machine Learning to Skewed Data The Dairy industry requires accurate detection of oestrus(heat) in dairy cows to maximise output of the animals. Traditionally this is a process dependant on human observation and interpretation of the various signs of heat. Many areas of the dairy industry can be automated, however the detection of oestrus is an area that still requires human experts.
This thesis investigates the application of Machine Learning classification techniques, on dairy cow milking data provided by the Livestock Improvement Corporation, to predict oestrus. The usefulness of various ensemble learning algorithms such as Bagging and Boosting are explored as well as specific skewed data techniques.
An empirical study into the effectiveness of classifiers designed to target skewed data is included as a significant part of the investigation. Roughly Balanced Bagging and the novel Under Bagging classifiers are explored in considerable detail and found to perform quite favourably over the SMOTE technique for the datasets selected. This study uses non-dairy, commonplace, Machine Learning datasets; many of which are found in the UCI Machine Learning Repository.

year: 2009

title: Catecholamine physiology in the sheep

authors: Pearson, Allan John

abstract: A study of catecholamine physiology in the sheep has been carried out with emphasis on the measurement of plasma catecholamine levels and their interactions with lactic acid and cortisol. The plasma dynamics of the catecholamines were first examined under laboratory conditions followed by an assessment of sympathetic responses to a variety of environmental stimuli.
Catecholamine levels were monitored in the plasma of sheep during and after 90 minute infusions of 1-dopa, dopamine, noradrenaline and adrenaline. A 2-compartmental pharmacokinetic model of 1-dopa plasma dynamics was constructed and the half-lives of the fast and slow decay curves determined. Estimation of the half-lives of dopamine, noradrenaline and adrenaline was prevented by a period of increased endogenous secretion that occurred on the termination of the infusions. A hypothesis based on the hypotension developed by sheep on the arrest of catecholamine infusions of this nature was developed to explain the adrenergic activity observed. Lactic acid levels rose markedly during the adrenaline infusions with a much smaller response during noradrenaline infusions while a biphasic cortisol response to both the noradrenaline and adrenaline infusions was observed.
A set of blood samples was collected from each of 6 cannulated lambs at various stages of a journey from the farm to the abattoir. Catecholamine levels remained consistently elevated throughout the experiment before rising to a very high peak upon electrical stunning prior to slaughter. Plasma lactic acid peaks were associated with mustering and washing while cortisol remained high throughout the experiment until penning at the abattoir when it fell sharply to baseline levels. Subsequently it rose overnight. The physiological basis of these observations is discussed in relation to the transport of stock and the use of these blood substances in assessing the reactions of domestic animals to their environment.
The massive catecholamine release in response to electrical stunning was further studied in a series of experiments. Significant differences between lamb mobs slaughtered at an abattoir appeared but a relationship was not found between the catecholamine plasma concentrations and the haemorrhagic lesion known as “blood splash” caused by electrical stunning. Short-term stressors encountered by the lambs at the abattoir had no effect on the blood splash incidence but some evidence suggested a link with the previous behavioural and handling conditions of slaughtered lambs. Both the α-adrenergic and the β-adrenergic blocking drugs phentolamine and propranolol were effective in suppressing blood splash and the physiological basis of this observation is considered.
Some preliminary experiments to investigate catecholamine involvement in the neurological disease of ryegrass staggers in sheep are described together with a description of the intense ingestive behaviour and the possible taming effects induced by the central dopaminergic receptor blocker haloperidol.
The application of these and other results to future agricultural research programmes is considered in the light of recent developments in the understanding of the multiple roles of these substances in mammalian physiology.

text: Catecholamine physiology in the sheep A study of catecholamine physiology in the sheep has been carried out with emphasis on the measurement of plasma catecholamine levels and their interactions with lactic acid and cortisol. The plasma dynamics of the catecholamines were first examined under laboratory conditions followed by an assessment of sympathetic responses to a variety of environmental stimuli.
Catecholamine levels were monitored in the plasma of sheep during and after 90 minute infusions of 1-dopa, dopamine, noradrenaline and adrenaline. A 2-compartmental pharmacokinetic model of 1-dopa plasma dynamics was constructed and the half-lives of the fast and slow decay curves determined. Estimation of the half-lives of dopamine, noradrenaline and adrenaline was prevented by a period of increased endogenous secretion that occurred on the termination of the infusions. A hypothesis based on the hypotension developed by sheep on the arrest of catecholamine infusions of this nature was developed to explain the adrenergic activity observed. Lactic acid levels rose markedly during the adrenaline infusions with a much smaller response during noradrenaline infusions while a biphasic cortisol response to both the noradrenaline and adrenaline infusions was observed.
A set of blood samples was collected from each of 6 cannulated lambs at various stages of a journey from the farm to the abattoir. Catecholamine levels remained consistently elevated throughout the experiment before rising to a very high peak upon electrical stunning prior to slaughter. Plasma lactic acid peaks were associated with mustering and washing while cortisol remained high throughout the experiment until penning at the abattoir when it fell sharply to baseline levels. Subsequently it rose overnight. The physiological basis of these observations is discussed in relation to the transport of stock and the use of these blood substances in assessing the reactions of domestic animals to their environment.
The massive catecholamine release in response to electrical stunning was further studied in a series of experiments. Significant differences between lamb mobs slaughtered at an abattoir appeared but a relationship was not found between the catecholamine plasma concentrations and the haemorrhagic lesion known as “blood splash” caused by electrical stunning. Short-term stressors encountered by the lambs at the abattoir had no effect on the blood splash incidence but some evidence suggested a link with the previous behavioural and handling conditions of slaughtered lambs. Both the α-adrenergic and the β-adrenergic blocking drugs phentolamine and propranolol were effective in suppressing blood splash and the physiological basis of this observation is considered.
Some preliminary experiments to investigate catecholamine involvement in the neurological disease of ryegrass staggers in sheep are described together with a description of the intense ingestive behaviour and the possible taming effects induced by the central dopaminergic receptor blocker haloperidol.
The application of these and other results to future agricultural research programmes is considered in the light of recent developments in the understanding of the multiple roles of these substances in mammalian physiology.

year: 1979

title: Language, mātauranga Māori . . . and technology?

authors: Selby, Mereana

subjects: Māori language

abstract: In this paper, I report on a research project involving the creation of an e-learning environment for the teaching and learning of an aspect of te reo Māori, that is the preparation of mihi. It was found that learning in the context of an e-learning environment in which anonymity was assured, learners could learn in their own spaces and at their own pace and there was no pressure to perform in front of peers and tutors had the potential to reduce the potentially negative effects of whakamā.

text: Language, mātauranga Māori . . . and technology? In this paper, I report on a research project involving the creation of an e-learning environment for the teaching and learning of an aspect of te reo Māori, that is the preparation of mihi. It was found that learning in the context of an e-learning environment in which anonymity was assured, learners could learn in their own spaces and at their own pace and there was no pressure to perform in front of peers and tutors had the potential to reduce the potentially negative effects of whakamā.

year: 2006-09