Evaluation of the performance of dual-purpose cows in European pasture-based systems

The demand for organic products in Europe is growing, especially organic products of animal origin. Organic dairy milk production requires grazing of cows, which results in a feed ration that is pasture-based. The breed that is kept by far the most for dairy production in Europe is the Holstein Friesian cow, a high-yielding dairy cow. This cattle breed has been developed in North America and was selected for its high milk yield. The disadvantages of this one-sided selection for production manifest in the health, fertility and longevity of the cow. More important, the high milk yield of the Holstein Friesian is only achieved when the cows are fed a diet of high quality and especially concentrates, which is not always possible in a pasture-based system. In this study the alternative for the Holstein Friesian breed is considered, namely the dual-purpose cow. Most countries feature indigenous cow breeds which were traditionally kept for both milk and meat. Because of the popularity of the Holstein Friesian breed these local breeds are less used in dairy production systems. An extensive literature study was carried out to compare the popular Holstein Friesian breed to the local dual-purpose cattle breeds. This showed that local dual-purpose breeds display in many traits such as health, fertility, meat quality and longevity an advantage over the Holstein Friesian. Additionally, dual-purpose cows are better able to cope with a harsh environment and a diet of low quality. Furthermore, the grazing behaviour of one of the Dutch dual-purpose breeds, the Dutch Friesian, was compared in the current study to the Holstein Friesian. For this purpose the monitoring system SensOor (AGIS) was used. SensOor registers the four main conducts of the cows, namely eating, ruminating, resting and other activity (such as walking, standing, etc.). The system expresses the time the cows spend on these conducts in percentages per hour or per day. In this study the SensOor system was validated under grazing conditions for the first time. Before, the SensOor system was only validated indoors or in a dirt pen. The validation under grazing conditions was done by observing the behaviour of the cows on the pasture, and comparing these observations with the SensOor output. The observation of the activity ‘grazing’ corresponded very well with the detection of the activity ‘eating’ (R² = 0.97). As the validation of SensOor under grazing conditions was successful, the output of the system was used to compare the behaviour of the two cattle breeds. In the current study no significant differences in behaviour were found, which can be explained by the differences in size of the cows (HF: 650 kg, DF: 575 kg) which have therefore different energy requirements. Another explanation could be that the high quality of the grassland on the studied farm concealed the ability of dual-purpose cows to cope with low-quality roughages. Besides the study of the behaviour of the cows, the herbage production on two farms was estimated. This was done by the placement of grass cages on the pastures. The herbage growth under the cages was mown, weighed and analysed. In conclusion, the monitoring system SensOor is very suitable to monitor the grazing time of cows. The literature study showed that dual-purpose cows have advantages over the Holstein Friesian (especially in milk composition, meat quality, health and longevity). Concerning their grazing behaviour, dual-purpose cows might spend more time on grazing and constitute more grass in their diet. This difference in behaviour was not shown by the output of SensOor. The absence of this difference might be explained by the excellent environment of the Friesian pastures. It is expected that the advantage concerning grass and feed intake of dual-purpose cows are better demonstrated in a harsh environment with pastures of low quality

Life on the watershed

The scarcity of water is a major problem in many parts of the Near East today and has been so in the past. To survive in such a region people should be able to structurally attain more water than rainfall alone can supply. The archaeology of this area should not only identify when people inhabited such a region and what the character of this habitation was, but also how people were able to survive in such a region and why they chose to live there in the first place. In this book these questions have been studied for the Zerqa Triangle; a region in the middle Jordan Valley around Tell Deir ‘Alla (Jordan). By means of a detailed pedestrian archaeological survey the intensity of habitation of the region from the Neolithic to early modern periods is investigated. Efforts have been undertaken to reconstruct the agricultural practices in the various periods and simultaneously the means by which the different communities were able to practice agriculture; in other words, how did they irrigate the land? By focussing on the different social responses of communities conclusions have been drawn on how and why people managed to create a living in this arid, but potentially very fertile region. This book not only contributes to the ongoing discussion of the archaeology of marginal areas, but also provides a huge amount of new data on the archaeology of the Jordan Valley, both in the form of newly discovered settlement sites from several different periods as well as remains from several more inconspicuous types of human activity present in the countryside

Life on the watershed : reconstructing subsistence in a steppe region using archaeological survey: a diachronic perspective on habitation in the Jordan Valley.

Scarcity of water is a major problem in many parts of the Near East today and in the past. In order to survive in such a region people have to be able to structurally procure more water than rainfall alone can supply. The archaeology of this area should not only identify when people inhabited such a region and what the character of this habitation was, but also how people were able to survive in such a region and why they chose it in the first place. In this book these questions have been posed of the Zerqa Triangle: a region in the middle Jordan Valley around Tell Deir ‘All? (Jordan). The intensity of habitation of the region from the Neolithic to early modern periods was investigated by means of a detailed pedestrian archaeological survey. Efforts have been undertaken to reconstruct the agricultural practices in the various periods and simultaneously the means by which the different communities were able to practise agriculture; in other words, how did they irrigate the land? By focussing on the varying social responses of communities, conclusions have been drawn on how and why people created a living in this arid, but potentially very fertile region.LEI Universiteit LeidenNWOClassical & Mediterranean Archaeolog

The Trade-Off between Female Fertility and Longevity during the Epidemiological Transition in the Netherlands

Several hypotheses have been put forward to explain the relationship between women’s fertility and their post-reproductive longevity. In this study, we focus on the disposable soma theory, which posits that a negative relationship between women’s fertility and longevity can be understood as an evolutionary trade-off between reproduction and survival. We examine the relationship between fertility and longevity during the epidemiological transition in the Netherlands. This period of rapid decline in mortality from infectious diseases offers a good opportunity to study the relationship between fertility and longevity, using registry data from 6,359 women born in The Netherlands between 1850 and 1910. We hypothesize that an initially negative relationship between women’s fertility and their longevity gradually turns less negative during the epidemiological transition, because of decreasing costs of higher parities. An initially inversed U-shaped association between fertility and longevity changes to zero during the epidemiological transition. This does suggest a diminishing environmental pressure on fertility. However, we find no evidence of an initial linear trade-off between fertility and post-reproductive survival

Assessment of competency development in a challenge-based learning course: can coaches be objective assessors?

Higher education institutions aim to incorporate competency development into their engineering curricula, which can help engineering students become independent critical thinkers with entrepreneurial mindsets. However, no solid methods exist to evaluate the acquisition of these competencies. Such assessments’ objectivities are often ensured by distinguishing between who supervises a student group and who grades its project. The assessor’s active involvement in the learning process is essential for assessing competency development during the learning process, but such involvement may lead to assessor bias. This study aims to investigate whether and under what conditions coaches can be objective assessors. An intraclass correlation coefficient (ICC) was used to measure the level of agreement between assessors and coaches when using the same rubric to assess students’ deliverables. Four assessors and seven coaches from the University of Twente assessed 24 students’ individual learning processes based on individual reflection deliverables. The coaches assessed the students they supervised during a challenge-based learning (CBL) course, while the assessors were without participating in the learning process assigned randomly to students. The means were compared using SPSS, which indicated, among other things, that coaches generally awarded higher scores than assessors. This may indicate that coaches are biased because of their involvement in the learning process. Despite this, the results also indicate that coach assessment was in line with assessors when the coach was an appointed and experienced examiner