Nina Volkmann

Dr. Nina Volkmann

University of Veterinary Medicine Hannover, Foundation, Hanover, Germany
orcid

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

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

Representative Publications

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7 August 2019 in Animals
Verified
Journal Article
Open access
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TNThies Nicolaisen
Thies Nicolaisen
EEyke Lühken
Eyke Lühken
Nina VolkmannNina Volkmann
Nina Volkmann
KRKarl Rohn
Karl Rohn
Nicole KemperNicole Kemper
Nicole Kemper
MFMichaela Fels
Michaela Fels
Pens with farrowing crate (FC) and two differently designed free-farrowing pens (LH-pens: 7.3 m², plastic flooring; GH-pens: 5 m², cast-iron and concrete flooring) were compared regarding piglet losses and postpartum sow behaviour (all treatments) and reasons for piglet crushing and postpartum litter behaviour (LH and GH). One-hundred-and-three crushing events were analysed in eight batches concerning sows’ posture changes that crushed piglets and age of crushed piglets. Posture change frequency, amounts of single posture changes and total time spent in different body postures were evaluated for 41 sows (14 FC-sows, 13 LH-sows and 14 GH-sows) in six batches. Litter behaviour (location, active/inactive scoring, resting behaviour next to the sow) was analysed during sows’ posture changes and piglet crushing. Piglet mortality was higher in LH (25.6%) and GH (19.9%) compared to FC (12.3%) due to higher levels of piglet crushing. Most crushing occurred during the three days postpartum in LH (92.7%) and GH (83.9%). However, crushing patterns differed between LH (rolling: 68.2%; sit-to-lie: 18.2%; stand-to-lie: 11.4%) and GH (rolling: 38.2%; sit-to-lie: 30.9%; stand-to-lie: 16.4%) and varying piglet behaviour may be the cause for this. The postpartum period was characterized by inactivity of the sow and behavioural differences were rarely seen between systems.

1 May 2021 in Journal of Dairy Science
Verified
Journal Article
Closed access
Nina VolkmannNina Volkmann
Nina Volkmann
BKBoris Kulig
Boris Kulig
SHS. Hoppe
S. Hoppe
JSJ. Stracke
J. Stracke
OHO. Hensel
O. Hensel
Nicole KemperNicole Kemper
Nicole Kemper
Claw lesions are a serious problem on dairy farms, affecting both the health and welfare of the cow. Automated detection of lameness with a practical, on-farm application would support the early detection and treatment of lame cows, potentially reducing the number and severity of claw lesions. Therefore, in this study, a method was proposed for the detection of claw lesions based on the acoustic analysis of a cow's gait. A panel was constructed to measure the impact sound of animals walking over it. The recorded impact sound was edited, and 640 sound files from 64 cows were analyzed. The classification of animal-lameness status was performed using a machine-learning process with a random forest algorithm. The gold standard was a 2-point scale of hoof-trimming results (healthy vs. affected), and 38 properties of the recorded sound files were used as influencing factors. A prediction model for classifying the cow lameness was built using a random forest algorithm. This was validated by comparing the reference output from hoof-trimming with the model output concerning the impact sound. Altering the likelihood settings and changing the cutoff value to predict lame animals improved the prediction model. At a cutoff at 0.4, a decreased false-negative rate was generated, and the false-positive rate only increased slightly. This model obtained a sensitivity of 0.81 and a specificity of 0.97. With this procedure, Cohen's Kappa value of 0.80 showed good agreement between model classification and diagnoses from hoof-trimming. In summary, the prediction model enabled the detection of cows with claw lesions. This study shows that lameness can be detected by machine learning from the impact sound of hoofs in dairy cows.

25 April 2019 in Agriculture
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Journal Article
Open access
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THTatiana Hohnholz
Tatiana Hohnholz
Nina VolkmannNina Volkmann
Nina Volkmann
KGKathia Gillandt
Kathia Gillandt
RWRalf Waßmuth
Ralf Waßmuth
Nicole KemperNicole Kemper
Nicole Kemper
Dystocia and perinatal mortality are major animal health, welfare and economic issues in beef suckler cow production. The objective of this study was to identify risk factors for dystocia and perinatal mortality and to analyze the relationships of both traits to external pelvic parameters in extensively kept beef suckler cows. Calving ease and calf survival were recorded for 785 births on five Angus cattle farms in Germany. The prevalence of dystocia and perinatal mortality was 3.4% and 4.3%, respectively. A hierarchical model was used to predict dystocia and perinatal mortality. First-parity dams had a higher probability of dystocia (p < 0.0001) than later-parity ones. Increasing birth weight was associated with an increasing risk for dystocia (p < 0.05). The probability of perinatal mortality (p < 0.0001) was higher in assisted births than in unassisted births. Calves from first-parity dams had a higher risk (p < 0.01) of being stillborn than calves from dams in later parities. An increase in the length of the pelvis was associated with an increase in odds for perinatal mortality (p < 0.001). In conclusion, the study indicates that dystocia and perinatal mortality are mainly problems in first-parity suckler cows. Concerning the predictive value of external pelvic parameters, further research is necessary.

11 July 2022 in Sensors
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Journal Article
Open access
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Nina VolkmannNina Volkmann
Nina Volkmann
CZClaudius Zelenka
Claudius Zelenka
ADArchana Malavalli Devaraju
Archana Malavalli Devaraju
JBJohannes Brünger
Johannes Brünger
JSJenny Stracke
Jenny Stracke
RKReinhard Koch
Reinhard Koch
Injurious pecking against conspecifics is a serious problem in turkey husbandry. Bloody injuries act as a trigger mechanism to induce further pecking, and timely detection and intervention can prevent massive animal welfare impairments and costly losses. Thus, the overarching aim is to develop a camera-based system to monitor the flock and detect injuries using neural networks. In a preliminary study, images of turkeys were annotated by labelling potential injuries. These were used to train a network for injury detection. Here, we applied a keypoint detection model to provide more information on animal position and indicate injury location. Therefore, seven turkey keypoints were defined, and 244 images (showing 7660 birds) were manually annotated. Two state-of-the-art approaches for pose estimation were adjusted, and their results were compared. Subsequently, a better keypoint detection model (HRNet-W48) was combined with the segmentation model for injury detection. For example, individual injuries were classified using “near tail” or “near head” labels. Summarizing, the keypoint detection showed good results and could clearly differentiate between individual animals even in crowded situations.

1 March 2019 in Animals
Verified
Journal Article
Open access
PDF file
Nina VolkmannNina Volkmann
Nina Volkmann
BKBoris Kulig
Boris Kulig
Nicole KemperNicole Kemper
Nicole Kemper
An important factor for animal welfare in cattle farming is the detection of lameness. The presented study is part of a project aiming to develop a system that is capable of an automated diagnosis of claw lesions by analyzing the footfall sound. Data were generated from cows walking along a measurement zone where piezoelectric sensors recorded their footfall sounds. Locomotion of the animals was scored and they were graded according to a three-scale scoring system (LS1 = non-lame; LS2 = uneven gait; LS3 = lame). Subsequently, the cows were examined by a hoof trimmer. The walking speed across the test track was significantly higher in cows with LS1 compared to those with LS2 and LS3 and thus, they were showing a smoother gait pattern. The standard deviation of volume (SDV) in the recorded footfall sound signal was considered as a factor for the force of a cow’s footsteps. Cows with non-infectious claw lesions showed lower SDV than healthy cows and those with infectious claw diseases. This outcome confirmed the hypothesis that the evaluated cows affected by non-infectious claw lesions have a greater sensitivity to pain and demonstrate a less forceful gait pattern. These first results clearly show the potential of using footfall sound analysis for detecting claw lesions.

10 January 2019 in Frontiers in Veterinary Science
Verified
Journal Article
Open access
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Heidi ArndtHeidi Arndt
Heidi Arndt
Nina VolkmannNina Volkmann
Nina Volkmann
Birgit SpindlerBirgit Spindler
Birgit Spindler
JHJörg Hartung
Jörg Hartung
Nicole KemperNicole Kemper
Nicole Kemper
In this study, the floor area covered by individual finishing pigs in various body positions was measured using a contrast-based planimetric method for computer-assisted analysis of two-dimensional images. Two hundred and thirty-two finishing pigs were weighed during the last fifth of the fattening period and measured in different body positions using contrast-based planimetry. Thirteen body positions were defined based on characteristic directions of the head, legs and body. The lowest average covered floor area was found for body position A (pig standing up straight, nose touching the ground) with 0.288 ± 0.026 m2. The highest average covered floor area for a standing pig amounted to 0.335 ± 0.030 m2 in body posture ES (pig standing curved sideways, head raised above the dorsal line) and, for a lying pig, 0.486 ± 0.040 m2 (posture LL, pig lying in fully lateral recumbent position). The covered floor surface significantly depended on the weight of the animal and the body posture. Allometric estimations previously described for calculating the floor area physically covered by a pig's body are not consistently precise in depicting the actual areas covered. The minimal floor area offered in animal transportation vehicles, according to European legislation, is insufficient in the case of all pigs lying in the fully recumbent position simultaneously, without the pigs being forced to partially overlap one another. Therefore, both allometric formulas and legislation should be modified on the basis of these results and further studies with pigs of modern genetic origin should be conducted.