Christer Bergsten

Prof. Christer Bergsten


Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 September 2005 in Applied Animal Behaviour Science
Verified
Journal Article
Closed access
ETEvgenij Telezhenko
Evgenij Telezhenko
CBChrister Bergsten
Christer Bergsten

1 August 2007 in Journal of Dairy Science
Verified
Journal Article
Closed access
PDF file
ETE. Telezhenko
E. Telezhenko
LLLena Maria Lidfors
Lena Maria Lidfors
CBChrister Bergsten
Christer Bergsten
Concrete is the most commonly used alley flooring in confined dairy herds because of its qualities of construction and ease of cleaning. Nevertheless, the hardness, abrasiveness, and slipperiness of concrete floors have adverse effects on animal well-being and health, and yielding rubber flooring is becoming popular as a way of improving the flooring conditions on walkways. The aim of this study was to investigate preferences of dairy cows for rubber compared with concrete flooring under the conditions of a commercial dairy farm. The study was conducted in an organic dairy herd with free-stall housing. Floor preference was tested on groups of standing cows in a 120-m2 holding pen before milking, and 1 yr later on a 12- x 3-m walkway. The holding pen and the walkway were divided lengthwise into 2 identical sections. Two types of solid rubber mats (soft and extra soft) were tested against solid concrete in the holding pen. Slatted and solid rubber mats were tested against slatted concrete in the walkway. Each floor type was tested over 4 d on the left side and 4 d on the right side of the holding pen and the walkway, respectively. Concrete flooring on both sides of the sections was tested as a control before the testing of different section materials. All observations of the distribution of cows in the sections were made from video recordings captured in association with the afternoon milking. The number of cows on each section was recorded approximately every 7 min in the holding pen, and continuously on the walkway. A significantly higher proportion of cows stood on the side with the soft and extra soft rubber mats (65.1 +/- 2.7 and 69.3 +/- 2.6%, respectively, mean +/- SEM) compared with the control distribution when only the solid concrete was available (50.9 +/- 3.9%). A significantly higher proportion of nonlame cows walked exclusively on the side with the slatted (64.5 +/- 5.4%, d 4) or solid rubber mats (68.2 +/- 5.1%, d 4) compared with controls (28.9 +/- 4.3%). Lame cows within a group of walking cows did not show a higher preference for soft flooring as distinct as nonlame cows (52.7 +/- 6.9 and 59.4 +/- 6.2% for the solid and slatted rubber mats, respectively, at d 4 vs. 40.3 +/- 6.2% for control), presumably because of competition with other, higher ranked cows. It was concluded that the majority of cows preferred to walk and stand on soft rubber rather than on concrete flooring.

1 November 2004 in Applied Animal Behaviour Science
Verified
Journal Article
Closed access
JLJenny Loberg
Jenny Loberg
ETEvgenij Telezhenko
Evgenij Telezhenko
CBChrister Bergsten
Christer Bergsten
LLLena Maria Lidfors
Lena Maria Lidfors

31 March 2003 in Acta Veterinaria Scandinavica
Verified
Journal Article
Open access
PDF file
CBChrister Bergsten
Christer Bergsten

1 January 2015 in Animal
Verified
Journal Article
Open access
PDF file
MNM. Nilsson
M. Nilsson
AHAnders Herlin
Anders Herlin
HAH. Ardö
H. Ardö
OGO. Guzhva
O. Guzhva
KÅK. Åström
K. Åström
CBChrister Bergsten
Christer Bergsten
In this paper the feasibility to extract the proportion of pigs located in different areas of a pig pen by advanced image analysis technique is explored and discussed for possible applications. For example, pigs generally locate themselves in the wet dunging area at high ambient temperatures in order to avoid heat stress, as wetting the body surface is the major path to dissipate the heat by evaporation. Thus, the portion of pigs in the dunging area and resting area, respectively, could be used as an indicator of failure of controlling the climate in the pig environment as pigs are not supposed to rest in the dunging area. The computer vision methodology utilizes a learning based segmentation approach using several features extracted from the image. The learning based approach applied is based on extended state-of-the-art features in combination with a structured prediction framework based on a logistic regression solver using elastic net regularization. In addition, the method is able to produce a probability per pixel rather than form a hard decision. This overcomes some of the limitations found in a setup using grey-scale information only. The pig pen is a difficult imaging environment because of challenging lighting conditions like shadows, poor lighting and poor contrast between pig and background. In order to test practical conditions, a pen containing nine young pigs was filmed from a top view perspective by an Axis M3006 camera with a resolution of 640×480 in three, 10-min sessions under different lighting conditions. The results indicate that a learning based method improves, in comparison with greyscale methods, the possibility to reliable identify proportions of pigs in different areas of the pen. Pigs with a changed behaviour (location) in the pen may indicate changed climate conditions. Changed individual behaviour may also indicate inferior health or acute illness.

1 April 2004 in Preventive Veterinary Medicine
Verified
Journal Article
Closed access
JHJan Hultgren
Jan Hultgren
TMThomas Manske
Thomas Manske
CBChrister Bergsten
Christer Bergsten