Iris Kolkman
Ghent University
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Featured researches published by Iris Kolkman.
Animal | 2010
Iris Kolkman; Geert Opsomer; Stef Aerts; Geert Hoflack; Hans Laevens; Dirk Lips
At calving, purebred animals of the Belgian Blue (BB) breed are compromised by the incompatibility in size and shape of the dam and her calf, resulting in a very high incidence of dystocia problems. To clarify which body parts of the calf are of decisive importance to allow natural delivery and to investigate both the mean value as well as the variation among these body sizes within this breed (variation being an important condition for selection), measurements of nine body parts (body weight at birth (BW), body length (BL), length of the head (LH), shoulder width (SW), hip width (HW), heart girth (HG), withers height (WH) and the circumference of the fetlock of both the front (CFF) and the hind leg (CFH)) were assessed in 147 newborn purebred BB calves on 17 farms. Simple and partial correlations were assessed and we examined whether environmental factors (gender of the calf, parity of the cow, type of calving, season of birth and time of measurement after birth) were significantly associated with these specific calf measurements. The mean BW was 49.2 ± 7.1 kg. The average BL was 56.4 ± 4.5 cm and the mean LH was 24.4 ± 2.3 cm. Measurements obtained for SW and HW were 22.4 ± 2.2 and 22.9 ± 2.1 cm, respectively, whereas the mean WH was 71.1 ± 4.7 cm. Measurements of circumferences revealed a CFF of 17.9 ± 1.1 cm, a CFH of 18.0 ± 1.0 cm and a mean HG of 78.0 ± 5.4 cm. Partial correlations of the BW with eight body measurements were significant (P < 0.01) and ranged between 0.17 and 0.85; 0.42 and 0.88; and 0.24 and 0.88 when corrected for gender, parity and type of calving, respectively. BL (P < 0.01) and the CFF and CFH (P < 0.001) are larger in bull calves than in heifer calves. Calves born through caesarean section had broader SW (P < 0.01) and HW (P < 0.01) when compared with calves born after natural calving (defined as born per vaginam without assistance or with slight traction). Sizes of calves born out of multiparous cows were generally larger than of calves born out of heifers (SW: P < 0.001; HW: P < 0.05). As SW and HW are the broadest points of a BB calf, they are both candidates for being the limiting measures for calving ease, but the difference between HW and SW for the total data set was not different from zero (P > 0.05). In contrast to male calves in which no significant difference (between HW and SW) could be found, female calves show the difference between HW and SW that was significantly different from zero (P < 0.001); thus, in female calves, the HW is the most limiting factor of the calfs body. The significant variation in some body measures between the calves and the strong correlation within these sizes raises the possibility of selection towards smaller calves aiming to limit the dystocia problem in the BB breed. Furthermore, on the basis of our results, we were able to build equations for the farmer to use at the moment of calving containing the LH, the CF and the calfs gender to estimate SW and HW, the limiting body parts of the calf to be born naturally. Together with the knowledge of the pelvic size of the dam, this information gives the obstetrician or the farmer a more accurate prediction of the probability of natural calving at parturition.
Reproduction in Domestic Animals | 2010
Iris Kolkman; Geert Opsomer; Dirk Lips; B Lindenbergh; A. de Kruif; S. De Vliegher
The aim of this study was to describe the difficulties encountered during caesarean section (CS) in practice on mainly Belgian Blue (BB) cows and to identify the associated risk factors. Data were collected using a questionnaire completed by veterinarians of the Ambulatory Clinic of the Faculty of Veterinary Medicine, Ghent University (Belgium), immediately after performing a CS. Results revealed that the BB breed had fewer severe pre-operative problems than animals of other breeds, most probably due to the fact that CSs in this breed are performed in a very early stage of parturition. Mild as well as severe difficulties were more likely to happen during surgery in cows that had undergone a CS before. Cows at their second or third surgery had a significantly higher proportion of larger calves and more skin scar tissue was present, both increasing the risk of abdominal wall muscular and uterine haemorrhage. These factors can all lead to problems with exteriorization and suturing of the uterus; hence special attention is needed when performing a CS on a cow which has experienced the procedure before. The more experienced veterinarians were less likely to report difficulties during the operation than less experienced surgeons.
Reproduction in Domestic Animals | 2012
Iris Kolkman; Geert Hoflack; Stef Aerts; Hans Laevens; Dirk Lips; Geert Opsomer
Some anatomical characteristics of 507 Belgian Blue (BB) cattle, withers height (WH), heart girth (HG), the distance between the two tubera coxae (TcTc) and the distance between the two tubera ischiadica (TiTi), were compared with the internal pelvic measurements of width, height and area. Mean values were 58.9 ± 6.2 cm for TcTc, 14.6 ± 2.3 cm for TiTi, 15.2 ± 2.1 cm for pelvic width (PW), 18.8 ± 1.9 cm for pelvic height (PH) and 288.5 ± 60.9 cm(2) for pelvic area (PA). Cows that calved per vaginam had larger WH (p < 0.05), TcTc (p < 0.05) and TiTi (p < 0.001) and internal pelvic measurements [PH and PA (p < 0.001)] compared with those whose parturition was managed by caesarean section (CS): Correlations between internal pelvic measurements and TcTc were higher (r = 0.58-0.63) than TiTi (r = 0.22-0.28). Correlations between other external body measures such as HG and WH with the internal pelvic measurements were even higher for HG (r = 0.69-0.74) and for WH (r = 0.67-0.74). HG and WH, together with internal pelvic measures, may be added to estimated breeding values (EBVs) that should assist breeders in selecting cows that can calve per vaginam, thereby reducing the breeds dependence on elective CS for maintaining its unique characteristics.
Reproduction in Domestic Animals | 2007
Iris Kolkman; S. De Vliegher; Geert Hoflack; M. van Aert; Jozef Laureyns; Dirk Lips; A. de Kruif; Geert Opsomer
Reproduction in Domestic Animals | 2010
Iris Kolkman; Stef Aerts; H Vervaecke; Jo Vicca; J Vandelook; A. de Kruif; Geert Opsomer; Dirk Lips
Journal of Veterinary Medical Education | 2009
Philippe Bossaert; Lieselot Leterme; Tim Caluwaerts; Steven Cools; Miel Hostens; Iris Kolkman; Aart de Kruif
Livestock Science | 2009
Iris Kolkman; Geert Hoflack; Stef Aerts; R. D. Murray; Geert Opsomer; Dirk Lips
Vlaams Diergeneeskundig Tijdschrift | 2006
Iris Kolkman; Sarne De Vliegher; Catharina De Schauwer; Geert Opsomer; Aart de Kruif
Vlaams Diergeneeskundig Tijdschrift | 2005
Jozef Laureyns; Sarne De Vliegher; Iris Kolkman; Leen Vandaele; Aart de Kruif
Archive | 2010
Iris Kolkman