The effect of round-bale feeder design and roughage type on feed wastage in sheep feeding.

Feeding big round-bales in round-bale feeders are known to reduce labor and costs. However, one disadvantage is the high feed wastage. The aim of these experiments was therefore to investigate the effect of feeder design, type of roughage and size of round-bales on feed wastage in sheep. Four round-bale feeders (Diagonal Rail Sheep Circular Feeder (RD), Knarrhult Flexible Round-Bale Feeder (KR), Telemark Round-Bale Feeder (TR) and Standard Sheep Circular Ring Feeder (RV)) were distributed into four identical experimental pens and used in both experiments. In Experiment 1, two types of roughages were used; Roughage 1: low-quality, grass silage harvested at late stage of maturity with dry matter (DM) content of 560 g/kg and Roughage 2: high-quality, hay harvested at an early stage of maturity with DM content of 738 g/kg. In Experiment 2, ewes were offered hay harvested at the late stage of maturity with DM content of 766 g/kg as half and whole round-bales. In both experiments, four groups of 10 ewes of the Norwegian White breed were rotated between the experimental pens and each treatment lasted for 4 days. Feed wastage (roughage on the ground surrounding the feeder) was collected daily. The amount of feed wastage was generally high. The type of roughage (Experiment 1) had a large effect on feed wastage (P < 0.001), where Roughage 1 had a mean feed wastage of 1.88 kg DM/day per ewe and Roughage 2 had 0.48 kg DM/day per ewe. When Roughage 1 was provided, it was evident that the ewes pulled out the long fibrous stems of the feeders and left them as wastage while selecting the leaves. This was not the case for Roughage 2. When feeding half round-bales (Experiment 2), the mean feed wastage was 1.50 kg DM/day per ewe compared to 2.88 kg DM/day per ewe when feeding whole round-bales (P < 0.001). This is probably due to the ewes spending more time eating with their heads inside the feeder when fed half round-bales (P < 0.001) and thus dropped more of the potential wastage inside the feeder. Less feed inside the feeder may also be the reason that feed wastage decreased gradually from Day 1 to Day 4 in both experiments (P < 0.001). Feeder design also had a significant impact on feed wastage (P < 0.001). We conclude that providing early harvested roughage and feeding half round-bales significantly reduced feed wastage.

Effect of space allowance and flooring on the behavior of pregnant ewes.

Space allowance recommendations for pregnant ewes vary considerably. The aim of this experiment was to investigate the effect of space allowance and floor type on activity, lying position, displacements, and aggressive interactions in pregnant ewes. A 3 × 2 factorial experiment was conducted with space allowance (0.75, 1.50, and 2.25 m/ewe) and type of flooring (straw bedding and expanded metal flooring) as the main factors. A total of 48 pregnant ewes were randomly assigned to 6 groups with 8 ewes in each group. All groups were exposed to each treatment for 7 d. The ewes were video recorded for 24 h at the end of each treatment period and general activity, lying position in the pen, and social lying position were scored every 15 min. Displacements and aggressive interactions were scored continuously from 1030 to 1430 h. Mean lying time ( < 0.0001) and time spent lying simultaneously ( < 0.0001) increased whereas time spent eating ( < 0.001) and standing ( < 0.001) decreased when space allowance increased from 0.75 to 1.50 m/ewe. Further increasing the space allowance to 2.25 m/ewe, however, had no effect on these parameters. Sitting was observed only in the 0.75 m/ewe treatment. Type of flooring had no significant effect on general activity. Ewes in the straw bedding treatment spent more time lying in the middle of the pen than ewes on expanded metal ( < 0.0001), but space allowance had no significant effect on this parameter. The proportion of time spent lying against side walls increased ( < 0.0001) whereas the proportion of time spent lying against the back wall decreased ( < 0.0001) when the space allowance was increased. In general, the distance between the ewes when lying significantly increased when space allowance increased from 0.75 to 1.50 m/ewe. Total number of displacements when lying ( < 0.0001) and aggressive interactions when active ( < 0.001) decreased when space allowance increased from 0.75 to 1.50 m/ewe and further slightly decreased, although the decrease was significant only for displacements when lying, when space allowance increased to 2.25 m/ewe. Low-ranked ewes were not exposed to more aggressive behavior than high-ranked ewes. In conclusion, increasing space allowance from 0.75 to 1.50 m/ewe had positive effects on activity and behavior in pregnant ewes, but further increasing space allowance to 2.25 m/ewe had limited effects, as did type of flooring. Hence, recommended space allowance for pregnant ewes should not be lower than 1.50 m/ewe.

The ability of ewes with lambs to learn a virtual fencing system.

The Nofence technology is a GPS-based virtual fencing system designed to keep sheep within predefined borders, without using physical fences. Sheep wearing a Nofence collar receive a sound signal when crossing the virtual border and a weak electric shock if continuing to walk out from the virtual enclosure. Two experiments testing the functionality of the Nofence system and a new learning protocol is described. In Experiment 1, nine ewes with their lambs were divided into groups of three and placed in an experimental enclosure with one Nofence border. During 2 days, there was a physical fence outside the border, during Day 3 the physical fence was removed and on Day 4, the border was moved to the other end of the enclosure. The sheep received between 6 and 20 shocks with an average of 10.9±2.0 (mean±SE) per ewe during all 4 days. The number of shocks decreased from 4.38±0.63 on Day 3 (when the physical fence was removed) to 1.5±0.71 on Day 4 (when the border was moved). The ewes spent on average 3%, 6%, 46% and 9% of their time outside the border on Days 1, 2, 3 and 4, respectively. In Experiment 2, 32 ewes, with and without lambs, were divided into groups of eight and placed in an experimental enclosure. On Day 1, the enclosure was fenced with three physical fences and one virtual border, which was then increased to two virtual borders on Day 2. To continue to Day 3, when there was supposed to be three virtual borders on the enclosure, at least 50% of the ewes in a group should have received a maximum of four shocks on Day 2. None of the groups reached this learning criterion and the experiment ended after Day 2. The sheep received 4.1±0.32 shocks on Day 1 and 4.7±0.28 shocks on Day 2. In total, 71% of the ewes received the maximum number of five shocks on Day 1 and 77% on Day 2. The individual ewes spent between 0% and 69.5% of Day 1 in the exclusion zone and between 0% and 64% on Day 2. In conclusion, it is too challenging to ensure an efficient learning and hence, animal welfare cannot be secured. There were technical challenges with the collars that may have affected the results. The Nofence prototype was unable to keep the sheep within the intended borders, and thus cannot replace physical fencing for sheep.

Management of horses with focus on blanketing and clipping practices reported by members of the Swedish and Norwegian equestrian community.

Limited information is available on the extent to which blankets are used on horses and the owners' reasoning behind clipping the horse's coat. Research on the effects of those practices on horse welfare is scarce but results indicate that blanketing and clipping may not be necessary from the horse's perspective and can interfere with the horse's thermoregulatory capacities. Therefore, this survey collected robust, quantitative data on the housing routines and management of horses with focus on blanketing and clipping practices as reported by members of the Swedish and Norwegian equestrian community. Horse owners were approached via an online survey, which was distributed to equestrian organizations and social media. Data from 4,122 Swedish and 2,075 Norwegian respondents were collected, of which 91 and 84% of respondents, respectively, reported using blankets on horses during turnout. Almost all respondents owning warmblood riding horses used blankets outdoors (97% in Sweden and 96% in Norway) whereas owners with Icelandic horses and coldblood riding horses used blankets significantly less ( < 0.05). Blankets were mainly used during rainy, cold, or windy weather conditions and in ambient temperatures of 10°C and below. The horse's coat was clipped by 67% of respondents in Sweden and 35% of Norwegian respondents whereby owners with warmblood horses and horses primarily used for dressage and competition reported clipping the coat most frequently. In contrast to scientific results indicating that recovery time after exercise increases with blankets and that clipped horses have a greater heat loss capacity, only around 50% of respondents agreed to these statements. This indicates that evidence-based information on all aspects of blanketing and clipping has not yet been widely distributed in practice. More research is encouraged, specifically looking at the effect of blankets on sweaty horses being turned out after intense physical exercise and the effect of blankets on social interactions such as mutual grooming. Future efforts should be tailored to disseminate knowledge more efficiently, which can ultimately stimulate thoughtful decision-making by horse owners concerning the use of blankets and clipping the horse's coat.

Preference for shelter and additional heat in horses exposed to Nordic winter conditions.

REASONS FOR PERFORMING STUDY: Horses may adapt to a wide range of temperatures and weather conditions. Owners often interfere with this natural thermoregulation ability by clipping and use of blankets. OBJECTIVES: To investigate the effects of different winter weather conditions on shelter seeking behaviour of horses and their preference for additional heat. STUDY DESIGN: Observational study in various environments. METHODS: Mature horses (n = 22) were given a free choice test between staying outdoors, going into a heated shelter compartment or into a nonheated shelter compartment. Horse location and behaviour was scored using instantaneous sampling every minute for 1 h. Each horse was tested once per day and weather factors were continuously recorded by a local weather station. RESULTS: The weather conditions influenced time spent outdoors, ranging from 52% (of all observations) on days with mild temperatures, wind and rain to 88% on days with <0°C and dry weather. Shivering was only observed during mild temperatures and rain/sleet. Small Warmblood horses were observed to select outdoors less (34% of all observations) than small Coldblood horses (80%). We found significant correlations between hair coat sample weight and number of observations outdoors (ρ = 0.23; P = 0.004). CONCLUSIONS: Horses selected shelters the most on days with precipitation and horses changed from a nonheated compartment to a heated compartment as weather changed from calm and dry to wet and windy. Horse breed category affected the use of shelter and body condition score and hair coat weight were associated with voluntary shelter selection.

The effect of frozen grass silage on the feed intake and feeding behavior of pregnant ewes.

The aim of the current study was to investigate the effect of frozen grass silage on the feed intake, feed preferences, and feeding behavior of ewes. Two experiments were conducted, each involving 8 pregnant ewes in a Latin square design with 4 treatments: 1) frozen silage; 2) partly frozen silage; 3) frozen, chopped silage; 4) and unfrozen silage (control). In Exp. 2, the ewes in square 1 were fed grass silage with low DM content (LDM) and in square 2 the ewes were fed grass silage with high DM content (HDM). In both experiments, each treatment period lasted for 14 d. A feed preference test was conducted, where the ewes could choose between 2 of the experimental feed treatments for 1 d in a changeover design so that they were exposed to all pairwise combinations of the 4 treatments. On the last day of each experimental period in Exp. 1, the feeding behavior was scored by direct observation for 4 h. In Exp. 1 ( < 0.0001) and in Exp. 2 ( = 0.03), feed intake in the first 4 h after feeding was lowest on the frozen silage treatment and highest on the control treatment. The DMI in the first 4 h after feeding was higher ( = 0.005) in the HDM treatment than in the LDM treatment. The total daily feed intake in Exp. 1 was lowest on the frozen, chopped silage treatment and highest on the unfrozen silage treatment ( = 0.02). In Exp. 2, daily feed intake did not differ ( = 0.32) among treatments. Total daily feed intake was higher ( < 0.0001) in the LDM treatment than in the HDM treatment but there was no difference in the DMI. There was no difference in the preference for the different feed treatments, when considering either the first 4 h ( = 0.12 to = 0.86) or the whole 24-h period ( = 0.25 to = 0.53). Time spent eating normally was longer on the control treatment and shorter on the frozen silage treatments ( < 0.0001) whereas time spent eating by tearing off feed from the frozen block followed the opposite pattern ( < 0.0001). We conclude that intake of frozen silage was lower for the first 4 h but that frozen silage had a very moderate effect on daily feed intake. Partly thawing or chopping improved the feed intake. Treatment had no significant effect on feed preferences. Feeding frozen silage increased time spent tearing off feed from frozen block, but total time eating was moderately increased.

A Nordic survey of management practices and owners' attitudes towards keeping horses in groups.

Keeping horses in groups is widely recommended but limited information is available about how this is implemented in practice. The aim of this survey was to describe how horses are kept in the Nordic countries in relation to sex, age, breed, and equestrian discipline and to assess owners' attitudes toward keeping horses in groups. Horse owners in Denmark, Finland, Norway, and Sweden were approached using a web-based questionnaire, which was translated into 4 languages and distributed online via equestrian forums, organizations, and social media. The number of respondents was 3,229, taking care of 17,248 horses. Only 8% of horses were never kept in groups, 47% were permanently grouped for 24 h/d, and 45% were stabled singly but grouped during turnout. Yearlings were most often permanently kept in groups (75%), mares and geldings more commonly during parts of the day (50 and 51%, respectively), and stallions were often kept alone (38%). Icelandic horses were more likely to be permanently kept in groups (36%) than warmbloods (16%) and ponies (15%). Twice as many competition horses (51%) were never grouped compared with horses used for breeding (20%) or leisure purposes (15%). The majority of respondents (86%) strongly agreed that group housing benefits horse welfare and that it is important for horses to have the company of conspecifics (92%). Nevertheless, not all horses were kept in groups, showing that attitudes toward group housing may not necessarily reflect current management. The risk of injury was a concern of many respondents (45%), as was introducing unfamiliar horses into already established groups (40%) and challenges in relation to feeding in groups (44%). Safety of people (23%) and difficulties handling group-kept horses (19%) were regarded as less problematic. Results suggest that the majority of horses have the possibility to freely interact with other horses, either as fulltime members of a group during 24 h/d or during turnout. Future research should address the extent to which being a part-time member of a group affects horse welfare. For permanent group housing to become more widespread, such as it is the case for most farm animals, future research could focus on solving some of the reoccurring problems perceived with keeping horses in groups. The dissemination of evidence-based information on all aspects around keeping horses in groups can ultimately stimulate further positive changes in the management of group-kept horses.

Individual variation in eating speed of dry sows.

We investigated the variation in eating speed by individual pregnant sows and the influence of feeding dry compared to wet feed. A total of 39 Norwegian Landrace × Yorkshire dry sows, 13 primiparous and 26 multiparous, were included in the experiment. In experimental period 1, each sow was offered 2.2 kg of a standard concentrate feed without added water. In experimental period 2, the sows were offered the same weight of concentrate feed but after mixing with water at a ratio of 1:4, based on weight. The sows were kept in groups of 4 or 5 in pens with individual feeding stalls. The weighed allocations of feed were poured into the troughs before the sows were given access to the food. On d 1, the sows were allowed to eat for 15 min, on d 2 for 10 min, on d 3 for 5 min, on d 4 for 2 min 30 s, and on d 5 for 1 min 15 s. At the designated time, feed troughs were covered, blocking sow access, and residual feed was carefully removed and weighed. Mean consumption rate of dry feed was 183.2 g/min for the first 5 min and 169.7 g/min for the first 10 min. For wet feed, the mean consumption rate was 1,859.8 g/min for the first 5 min and 1,060.7 g/min for the first 10 min. After 5 min, the sows had consumed 41.6% of the dry feed (range 19.5 to 79.1%, CV = 31.0%) and 84.5% of the wet feed (range 54.3 to 99.1%, CV = 14.9%). After 10 min, the sows had consumed 77.1% of the dry feed (range 33.9 to 100.0%, CV = 24.9%) and 5 of the 39 sows had completely ingested their allotted feed. When feed was wet, sows finished 96.4% of the ration (range 72.7 to 99.1%, CV = 6.4%) after 10 min. The speed of eating dry feed was positively correlated with sow weight, both at 5 (R = 0.72, P < 0.001) and 10 min (R = 0.75, P < 0.001), but for wet feed, the correlation was weak at 5 min (R = 0.36, P < 0.05) and there was no correlation at 10 min (R = 0.20, P > 0.10). We conclude that dry feed resulted in larger individual variation in feed consumption rate than wet feed. Furthermore, whereas feed consumption rate was correlated with liveweight of the sow when eating dry feed, the relationship was not significant when sows ate wet feed.

Water footbath, automatic flushing, and disinfection to improve the health of bovine feet.

Disinfecting footbaths are used to treat and prevent interdigital dermatitis (ID) and heel horn erosion (HHE). However, many disinfectants are disadvantageous for the environment and, as an alternative, washing of the feet has been introduced. Our aim was to investigate the effect of water footbaths (trial 1), footbaths with CuSO4 (trial 2), automatic water flushing (trial 3), and water flushing followed by disinfection with a glutaraldehyde-based compound (trial 4) in 4 randomized controlled clinical trials performed in a freestall dairy herd of approximately 45 Norwegian Red cows. At trimming before and after each trial, hind foot diseases, hardness of the claw horn (in D-units), locomotion, and cleanliness of the claws were recorded. Before each trial, the cows were divided in comparable study and control groups, based on prevalence of ID and HHE, parity, and days in milk. Using a transponder-regulated gate, the study groups were led through a footbath (trials 1 and 2) or an automatic washer (trials 3 and 4), whereas the control groups were left untreated. Each trial lasted 3 mo and the curative effect in diseased cows and the preventive effect in cows with healthy feet on ID, HHE, and ID + HHE were analyzed. In trial 2, a preventive effect of CuSO4 on HHE compared with the untreated cows was observed. During trial 1, 100% (11/11) of the treated cows with ID got better and 22% (2/9) without ID became diseased, whereas 92% (11/12) of the treated cows with ID + HHE got better and 38% (3/8) without ID + HHE became diseased. During trial 2, 69% (9/13) of the treated cows with ID got better and 11% (1/9) without ID became diseased. During trial 4, 19% (3/16) of the untreated cows with ID + HHE got better and 71% (5/7) without ID + HHE became diseased. In trial 3, no significant effects on ID, HHE, or ID + HHE were revealed. In trial 2 (CuSO4), the treated cows' claw horn was harder after the trial compared with the controls (D-unit difference: 13.25). In trial 3 (stationary water flushing) the treated cows' claw horn was softer after the trial when compared with the controls (D-unit difference: -15.66). The CuSO4 footbaths were useful to prevent HHE and indicate that automatic stationary flushing with only water had no beneficial effect on ID or HHE. The claw horn of cows walking through CuSO4 became harder and the claw horn of cows that had their hind feet flushed with water became softer compared with the controls.

Feed intake and competition in ewes on ad libitum or semi-restricted feeding of grass silage and hay.

The aim of the present experiment was to investigate the effect of feeding level and type of roughage on feed intake, feeding behavior and competition of ewes. A 2 × 2 factorial experiment was conducted with amount of roughage available (ad libitum or semi restricted) and type of roughage (grass silage or hay) as main factors. Forty-eight ewes were randomly assigned to 8 groups of 6 ewes. All groups were subjected to all 4 treatments, each treatment period lasted 7 d, and the order of treatments was rotated systematically. The ewes were video recorded for the 2 last days of each treatment period and feeding and general activity were scored every 10 min. All aggressive interactions and displacement at the feed barrier were scored continuously the first 3 h after feeding. Daily feed intake (P < 0.0001) and DMI (P < 0.0001) were both greater in the silage than in the hay treatment. Ewes in the semi-restricted treatment spent less time feeding (P < 0.0001), had a greater individual variation in feeding time (P < 0.05) and spent more time queuing for feed (standing maximum 1.5 m from the feeding barrier with the head towards the feed; P < 0.0001). Individual data showed that 5 ewes fed hay and 3 ewes fed silage reduced their time spent feeding more than 50% when the feeding level was reduced. When fed hay, the level of feeding did not affect number of aggressive interactions or displacements, but when fed silage the number of aggressive interactions (P < 0.01) and the number of displacements (P < 0.05) were much greater in the semi-restricted than in the ad libitum treatment. We conclude that even a minor restriction in the level of feeding will decrease time spent feeding and increase queuing and number of aggressive interactions when feeding space is also restricted, and that the increase in aggressive interactions is mainly for ewes fed grass silage.

Flexible and fixed partitions in freestalls--effects on lying behavior and cow preference.

The objective was to investigate the effect of stall partition design on total lying time, lying position, and stall cleanliness, and to evaluate the preferences of cows regarding stalls with traditional fixed stall dividers or flexible stall dividers. Using a crossover design, 16 nonlactating dairy cows were housed singly for 9 d in pens with 2 freestalls, 1 with fixed cantilever dividers and 1 with flexible dividers. The cows were first given access to one stall type, and then to the other type of stall, and finally to both in a preference test. Type of stall divider did not influence lying behavior (13.5h for fixed versus 14.0 h for flexible, ± 0.4h), lying positions, or stall cleanliness; however, the cows showed a preference for lying in the flexible stalls (65.2 for flexible vs. 34.8 for fixed ± 8.2%). This indicated that cows are able to distinguish between type of stall divider and that it is important to them; however, it is not clear if the reason for this is the shape or the properties of the dividers. We concluded that cattle chose a flexible stall divider over a fixed one, but the long-term consequences of this preference are not clear, because no obvious changes in stall usage were observed when cows were only given access to one type of divider.

Layouts for small freestall dairy barns: effect on milk yield for cows in different parities.

Freestall housing for dairy cows has many different layouts and the space allocated for cows differs considerably. The objective of the present study was to investigate possible associations between barn layout and milk yield for different parities in small dairy freestall barns. Layouts of 204 Norwegian freestall barns constructed during the period from 1995 to 2005, and with a mean herd size of 42.7±15.5 cows, were obtained and merged with milk yield data and calving interval, for each parity, from the Norwegian Milk Recording System (NDHRS). The milk yield data set contained 20,221 different lactations from these 204 herds. Both simple mixed models, including the different explanatory variables one by one together with parity, calving interval, and herd as random effect, and a final mixed model, including all significant explanatory variables, were created. According to variables tested in this study, the final mixed model estimates show that only primiparous cows benefit significantly from increased free space allocation. Milk yield was generally higher in automatic milking system barns compared with that in barns with milking parlors, but not for primiparous cows. Milk yield was higher for all parities for barns using separation pens in accordance with the recommendations. Barns with 2 or more dead-end alleys had lower milk yield compared with that from layouts without dead-end alleys. Primiparous cows benefited from water troughs located for easy access and responded with increased milk yield. In 10% of the barns, the water trough capacity was less than 47% of the recommendations, and all parities benefited from a water trough capacity higher than this level. Higher parities had increased milk yield when water trough capacity was more than 80%. Feed bunk space, number of freestall rows, and the location of freestalls had no significant effect on the milk yield. The present study showed that increased space and improved access to water is beneficial to primiparous cows, whereas layouts without dead-end alleys and improved water capacity is beneficial for all cows in freestall systems.

Risk factors for dirty dairy cows in Norwegian freestall systems.

Cow cleanliness is important for ensuring hygienic milk production and the well-being of dairy cows. The aim of this cross-sectional field study was to describe cow cleanliness in freestall-housed dairy herds and to examine risk factors related to thigh cleanliness. Cow cleanliness (n=2,335), management-related variables (e.g., ventilation and use of sawdust-bedded stalls), and housing-related variables (e.g., freestall design and number of cows per stall) were recorded in 232 Norwegian freestall-housed dairy herds. Cleanliness was scored on a 4-point scale ranging from clean (1) to very dirty (4). The cows were relatively clean on the udder and belly, dirtier on thigh and the rear part of the body, and dirtiest on the legs, with cleanliness scores (mean ± SD) of 1.64±0.62, 1.62±0.65, 2.02±0.75, 1.77±0.58, and 2.30±0.59, respectively. With dirty thighs as the response variable, several variables were tested in a logistic regression mixed model and with repeated measurements within herd and cow. A high number of cows per freestall [odds ratio (OR)=3.45], no use of sawdust as bedding (OR=3.24) versus use of sawdust, and a low-positioned (<0.85 m above stall floor) upper head rail "enclosing" the front of the stall (OR=1.42 to 2.13) versus a position >0.85 m were all risk factors for dirty thighs on the cows. Furthermore, liquid manure (score 2) versus more consistent manure (score 1; OR=1.66) and less tame cows (score 2) versus tame cows (score 1) were associated with an increased risk of dirty thighs (OR=1.24). The cleanest cows were associated with indoor temperatures in the range from 10 to 15°C. For each 10-percentage-unit increase in relative air humidity, the risk of dirty thighs increased (OR=1.32). Freestalls with a construction hindering normal lying, rising, and standing movements should be avoided. Furthermore, focus is needed on indoor climate and manure consistency to obtain cows with clean thighs.

Risk factors for skin lesions on the necks of Norwegian dairy cows.

Physical restrictions at the feed barrier may cause skin lesions, especially on the necks of cows. Thus, some aspects of the functionality of feed barrier design can be assessed by observing skin lesions on the necks of dairy cattle. In this study, 232 herds, mainly of the breed Norwegian Red (94%), were investigated between September 2006 and June 2007. The herds were categorized into 2 groups. One data set, based on 1,148 cows (115 herds), was from farms using feed barriers with post-and-rail designs (86 herds) and combinations of barriers (29 herds). The second data set, which included 1,168 cows (117 herds), was from farms using only vertical feed barriers such as tombstone, diagonal, and headlock. Skin lesions were observed on the necks of 21% of the 2,335 cows observed. Forty-two percent of cows had neck lesions in herds with post-and-rail barriers, whereas 4% of cows had neck lesions in herds with vertical barriers and 30% of cows had neck lesions in herds with a combination of both horizontal and vertical barriers. Alternating logistic regression was used to identify factors associated with skin lesions on the necks of cows. The estimates were transformed into odds ratios (OR). In herds in which post-and-rail design barriers were used, the following risk factors were associated with skin lesions: manger front lower than 63 cm versus higher (OR=3.6), no feed stalls versus feed stalls (OR=10.9), mixed rations versus no mixed ration (OR=3.8), cows later than 30 DIM versus earlier (OR=1.9), cows with low milk production versus those producing 1,000 kg higher (OR=1.4), feeding frequency of less than 3 times daily versus 3 and more times daily (OR=1.9), using only post-and-rail feed barriers (OR=1.8) versus using combinations, and farmer disagreement with the statement "animals experience physical pain as humans do" (OR=1.9) versus agreement. Diagonal barriers, categorized as vertical barriers, increased the association of skin lesions with increasing manger front heights. Feed barrier design was associated with skin lesions on the necks of cows, particularly for barriers of a post-and-rail design. To minimize the risk of neck lesions, the top rail height of post-and-rail barriers should be above 109 cm, especially for cows taller than 126 cm, and the manger front should not be lower than 63 cm. Feed stalls, feeding frequency of 3 or more times daily, and the feeding of unmixed rations were also identified as preventive factors.

The effect of group composition and age on social behavior and competition in groups of weaned dairy calves.

The objective of the present study was to investigate how group composition affects behavior and weight gain of newly weaned dairy calves and how age within heterogeneous groups affects behavior and competition. Seventy-two calves were introduced into 6 groups of 12 calves, of which 3 groups were homogeneous and 3 groups were heterogeneous (including 6 young and 6 old calves). The 9.8 mx9.5 m large experimental pen had 4 separate lying areas as well as a feeding area. Behavior and subgrouping were recorded on d 1, 7, and 14 after grouping, and calves were weighed before and after the experimental period of 14 d. Analysis of the effect of group composition on behavior and weight gain included young calves in heterogeneous groups and calves in homogeneous groups within the same age range at grouping (30 to 42 d). Irrespective of group composition, time spent feeding and lying increased, whereas time spent active decreased from d 1 to 7. In homogeneous groups, calves were more explorative on d 1 after grouping. Finally, calves in homogeneous groups had a higher average daily weight gain than calves in heterogeneous groups. Analysis of the effect of age included young and old calves of heterogeneous groups. Young calves were less explorative than old calves. Young calves were more active than old calves on d 1 but less active on d 7. Time spent lying and lying alone increased over time. More displacements from the feed manger were performed by old calves than by young calves. An analysis including all calves in both homogeneous and heterogeneous groups showed that when lying, calves were evenly distributed on the 4 lying areas and formed subgroups of on average 3 calves. In conclusion, age heterogeneity leads to increased competition, which may have a negative influence on the young calves' performance.

Associations of soft flooring materials in free stalls with milk yield, clinical mastitis, teat lesions, and removal of dairy cows.

The objective was to test if there was an association between free-stall base softness and milk yield, incidence of clinical mastitis (CM), teat lesions, and removal of cows. In a questionnaire sent to 1,923 dairy farms presumed to be using free-stall housing, farmers were asked for information regarding housing and stall base; for example, the year of installation and the product name or brand of their mats or mattresses. This information was merged with data for milk yield, CM, teat lesions, and removal of cows extracted from the Norwegian Dairy Herd Recording System for the years after installation of mats or mattresses. After exclusion of invalid contributions, the data set consisted of 29,326 lactations for milk yield distributed over 363 free-stalled herds in Norway. The farms were stratified into 5 categories according to the softness of the stall surface measured as millimeter impact of a sphere with a diameter of 120 mm at 2-kN load: 1=concrete, softness of 0mm; 2=rubber, softness of 1 to 8mm; 3=soft mats, softness of 9 to 16 mm; 4=multilayer mats, softness of 17 to 24 mm; and 5=mattresses, softness over 24 mm. Lactation curves were estimated as modified Wood's lactation curves using test-day data and mixed models with repeated measurements, adjusting for days in milk, parity, and softness of free-stall flooring. Herds on concrete free-stall bases yielded 6,727+/-146 kg of milk from 5 to 305 days in milk. In comparison, herds showed a decrease of 0.3% on rubber, an increase of 2.4% on soft mats, an increase of 4.5% on multilayer mats, and an increase of 3.9% on mattresses. Compared with concrete, the hazard ratio (HR) of CM was less on rubber, multilayer mats, and mattresses [HR=0.89 (0.79-0.99), 0.85 (0.73-0.996), and 0.80 (0.73-0.88), respectively]. Compared with concrete, the HR of teat lesions was less on rubber, soft mats, multilayer mats, and mattresses [HR=0.41 (0.26-0.65), 0.33 (0.24-0.44), 0.12 (0.04-0.38), and 0.47 (0.33-0.67), respectively]. The HR of removal of cows was less on mattresses compared with concrete, rubber, soft mats, and multilayer mats, with HR=0.90 (0.84-0.97), 0.88 (0.80-0.97), 0.86 (0.80-0.93), and 0.85 (0.76-0.95), respectively. A soft free-stall base contributed significantly to increased milk yield and fewer incidences of CM, teat lesions, and removal of cows.

Drying and warming immediately after birth may reduce piglet mortality in loose-housed sows.

The aim of the present experiment was to investigate the effects of placing newborn piglets under the heat lamp or both drying and placing them under the heat lamp on piglet mortality. Sixty-seven healthy (Landrace × Yorkshire) sows were divided equally into three different experimental groups: a control group where the farrowings occurred without supervision from the farmer (C; n = 23 litters), another group where the piglets were placed under the heat lamp in the creep area immediately after birth (HL; n = 22 litters) and a third group where the piglets were dried with straw and paper towels followed by placing them under the heat lamp in the creep area immediately after birth (DHL; n = 22 litters). The sows were individually loose-housed in farrowing pens during farrowing and lactation. The piglets were not closed inside the creep area, but were free to move around in the pen. The routines in the experimental groups required the stock person to attend the farrowings from the onset of birth of the first piglet until the last piglet was born. All the dead piglets were weighed and subjected to a post mortem examination at the farm to ascertain the causes of death. Postnatal mortality (% of live born) was significantly lower in the HL and DHL groups than in the control group (P < 0.0001). This was significant concerning all causes of mortality. Compared to the control group, crushing occurred in significantly fewer litters when the piglets were both dried and placed under the heat lamp (P < 0.05). In the DHL treatment, crushing of one or more piglets by the sow occurred in only 13.6% of the litters, whereas this was increased to 34.8% in the HL and to 47.9% in the control group, respectively. All causes of death, except the proportion of stillborn piglets, increased significantly with increasing litter size. Because of the relatively large potential that these rather simple routines may have to improve piglet survival, different types of management or human interference around the time of farrowing should be compared on a larger scale, both experimentally and on commercial farms.

Effect of infrared temperature on thermoregulatory behaviour in suckling piglets.

The objective of this study was to investigate the effect of infrared (IR) temperature on thermoregulatory behaviour in suckling piglets in the first 3 weeks after farrowing. A total of 10 piglets from each of the 16 litters were exposed to recommended IR temperature conditions at 1, 2 and 3 weeks of age, with a mild offset (4°C) in IR temperature during the first experiment and a more challenging offset (8°C) during the second experiment. Digital photos were taken when all piglets had settled in the creep area, and the lying posture and huddling behaviour were analysed. A lying posture score and a huddling score was calculated by multiplying the number of piglets in each category with a given value for each category, based on different lying postures and different degrees of huddling behaviour. With a 4°C change in IR temperature, the piglets tended to alter their lying posture, while an 8°C change had a significant effect on lying posture (P < 0.01). A change in IR temperature of 4°C had no effect on the degree of huddling. The huddling score decreased significantly with 8°C change in IR temperature (P < 0.05). Postural changes, rather than changes in degree of huddling were the preferred thermoregulatory strategy for suckling piglets.

Is snow a sufficient source of water for horses kept outdoors in winter? A case report.

Due to extreme weather conditions, a flock of outwintered Icelandic horses had to manage for several days on snow as the source of free water. They were fed grass silage ad lib, and any change in feed consumption was not observed. After nine days, blood samples were taken and analysed for plasma osmolality, they were subjected to a simple clinical examination, and offered drinking water. Osmolality levels were within normal limits and mean value did not differ significantly from samples which previously were taken of the same individuals. The general condition of the horses was normal, with no signs of clinical dehydration or disease. The horses showed very little interest for the offered drinking water. This suggests that in cold winter weather, horses being fed grass silage and adjusted to eat snow, can manage for several days with snow substituting liquid water without their physiology and welfare being challenged.

Effects of photointensity and photoperiod on milk yield and reproductive performance of Norwegian red cattle.

Relationships between light exposure, milk yield, and reproductive traits in Norwegian Red cattle were studied using data from 1538 farms in southern Norway during the darkest part of the year (November 1 to February 28). Production level was expressed as milk yield at first artificial insemination (AI) and 305-d milk yield. Reproductive performance was calculated using the following dependent variables: age at first AI, age at first calving, days open, calving interval, number of AI per cow, and nonreturn rate at 60 d. Days open and calving interval were both 4.0 d shorter, number of AI per cow was 0.07 less, non-return rate was 3.1% greater, and daily milk yield at first AI was 0.5 kg greater in herds that used dim illumination at night compared with herds that used no illumination at night. Milk yield at first AI was 0.5 kg greater in herds with photoperiods > 12 h. Photoperiods > 12 h were associated with a reduction in age at first AI by 4.8 d and age at first calving by 6.6 d. We concluded that dairy cattle kept at high latitudes during winter should be exposed to dim illumination at night and a minimum photoperiod of 12 h to stimulate reproductive performance and milk yield.