Airborne transmission of classical swine fever virus under experimental conditions

Sixty-one pigs were housed in an isolation unit with three compartments and five pens. Each compartment had its own ventilation system resulting in air currents flowing from compartment A (pens 1 to 3) towards compartment B (pen 4), but not towards compartment C (pen 5). Classical swine fever virus was introduced by the experimental inoculation of one pig in the middle pen (pen 2) of compartment A. The virus infected the pigs in pen 4, following the prevalent air currents, and the compartmentalisation had only a retarding effect on the transmission of the virus. The absence of infection in the pigs in pen 5, which was not different from pen 4 except for the ventilation system, indicates that the spread of virus was affected by the air currents.     

Effects of tropical climate and water cooling methods on growing pigs'' responses

We report a study on crossbred growing pig ((Duroc × Pietrain) × Large White) that measured the effect of tropical conditions on respiration rate (RR), skin temperature (ST), rectal temperature (RT) and productivity and determined the efficacy of two simple cooling methods. The experiment was a randomized complete block design using 120 growing pigs. The factors were cooling system and pen design. The effects of two cooling systems (water bath (WB) and sprinkling (S)) were evaluated and compared with a control (CON). Cooling systems were tested in pens with (Y) or without an additional outdoor yard (NY). The pens were similar to those used in small-scale pig keeping in South-East Asia. The inside pen size was 2.5 × 3 m, the yard was 2.5 × 2 m. The same experimental design was used in two blocks: one block was in the wet season with average ambient temperature (T) of 27.5 °C and average relative humidity (RH) of 74.7% and the other was in the dry season with average T of 28.7 °C and average RH of 62.8%. In each block a batch of 60 pigs was reared in 12 pens (five pigs per pen). Pigs had free access to feed and water. Results showed that cooling and pen type significantly affected most parameters. The bath and S reduced RR by 4.2 and 5.2 min^− 1, respectively (P < 0.01), and ST by 0.3 and 0.4 °C, respectively, (P < 0.05). Rectal temperature was not influenced by any treatment. The bath significantly reduced number of defecations and urinations in the resting area in pens NY (P < 0.001). A yard reduced the number of excretions in the resting area (P < 0.01). There were significant interaction effects of cooling and pen type on lying, lateral lying, and huddling (P < 0.01; P < 0.001; P < 0.01, respectively). Daily weight gain was 6 g d^− 1 more with WB and 50 g d^− 1 more with S (P < 0.05). The biggest daily weight gain was achieved when S was combined with a pen NY (P < 0.01).

We conclude that the physiologic and behavioral responses and hence productivity of group-housed growing pigs raised under tropical climate conditions benefited from the simple cooling systems tested and were affected by the presence of a yard. A fall in the high respiration rate indicated that cooling with the bath or sprinkling alleviated the pigs' heat stress.     

A cross-sectional study of the prevalence and associated risk factors for bursitis in weaner, grower and finisher pigs from 93 commercial farms in England

A cross-sectional study of 93 farms in England was carried out to estimate the prevalence and associated risk factors for bursitis. A total of 6250 pigs aged 6–22 weeks were examined for presence and severity of bursitis. Details of pen construction, pen quality and farm management were recorded including floor type, presence of bedding, condition of the floor and floor materials. The prevalence of bursitis was 41.2% and increased with each week of age (OR 1.1). Two-level logistic regression models were developed with the outcome as the proportion of pigs affected with bursitis in a pen. Pigs kept on soil floors with straw bedding were used as the reference level. In comparison with these soil floors, bursitis increased on concrete floors where the bedding was deep throughout (OR 4.6), deep in part (OR 3.7), and sparse throughout (OR 9.0), part slatted floors (OR 8.0), and fully slatted floors (OR 18.8). Slip or skid marks in the dunging area (OR 1.5), pigs observed slipping during the examination of the pen (OR 1.3) and wet floors (OR 3.6) were also associated with an increased risk of bursitis. The results indicate that bursitis is a common condition of growing pigs and that the associated risk factors for bursitis were a lack of bedding in the lying area, presence of voids and pen conditions which increased the likelihood of injury.     

Effects of amperozide and azaperone on aggression and productivity of growing-finishing pigs

Levels of aggression, activity and performance were determined in 270 pigs (initial wt 29.8 kg) injected with amperozide (1.0 mg/kg i.m.), azaperone (2.2 mg/kg i.m.) or saline (.1 ml/kg i.m.) immediately prior to mixing. Pigs had ad libitum access to feed in pens of 15, and six pens were allotted to each treatment. Each pen was video-taped for 48 h after injection. Aggression was determined by continuous observation and summarized for each 2-h period. Injuries on the ears and shoulders of each pig were scored prior to injection and 1, 2, 3 and 7 d after treatment. Eating, drinking and lying were determined by scan sampling at 2-min intervals and summarized for each 2-h period. Weight gain, feed consumption and efficiency were determined for periods ending on d 3, 7, 14, 28, 42, 56, 70 and 84. Both drugs reduced total fighting from 309.8 min for saline to 190.7 and 189.6 min for amperozide- and azaperone-treated pens, respectively (P less than .01). Treatment differences in aggression and lying were evident during the initial 6 h only. Amperozide resulted in fewer fights involving two pigs (197.3/pen) than did azaperone (260.2/pen) or saline (298.3/pen) (P less than .05). Injuries to the ears (P less than .01) and total injuries (P less than .05) were less severe in amperozide-treated pigs than in pigs on the other treatments.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of sensory stimuli on huddling behavior of pigs

Two experiments involving pigs at 1, 3, and 8 d of age were conducted to 1) compare huddling between littermates and nonlittermates, 2) study the ability of pigs to distinguish an anesthetized piglet from a piglet-shaped object, and 3) explore the importance of physical contact between pigs on huddling behavior. Experiments were conducted in an enclosed rectangular aluminum test chamber having pressure sensors beneath floor panels to detect test pig location. Test objects were placed on a platform at one end of the chamber and test pig location was monitored during a 45 min trial. Experiment 1 involved a total of 45 pigs (5 pigs/treatment on d 1, 2, and 3). The results indicate that, regardless of age (P > .05), when either a littermate or a nonlittermate occupied the platform, average location of test pigs that "settled" (ceasing to move for 7 min or more) was closer to the platform (P < .01), time spent near the platform was greater (P < .01), and movement about the chamber was less (P < .01) than when the platform was empty. No differences (P > .05) were observed between littermate and nonlittermate stimuli for these variables. During Exp. 2, the platform was covered with wire mesh. A total of 98 pigs were used in the study. Treatments were a cage containing 1) no object (n = 24), 2) a wooden block (n = 25), 3) a pig-shaped latex casting (n = 24), or 4) an anesthetized 8- to 10-d-old pig (n = 25). Pig age and treatment did not affect the percentage of time in each trial that pigs spent within 23.5 cm of the cage or the percentage of pigs settling within 23.5 cm of the cage. These studies show that pigs huddle similarly with littermates and nonlittermates and that physical contact with another piglet but not visual recognition of another piglet affects piglet huddling.     

Prevalence and risk factors associated with adventitious bursitis in live growing and finishing pigs in south-west England

The prevalence and risk factors associated with adventitious bursitis in 912 growing and finishing pigs, originating from 20 different housing systems in south-west England, were investigated in this study. The overall prevalence of bursal lesions was 63.4%. Bursae were seen at different aspects of the hock: lateroplantar, plantar, medial and point of the hock. The most frequently affected site was lateroplantar (54.4%) followed by plantar (12.5%), medial (2.0%) and finally the point of the hock (0.7%). There was no difference in the proportions of left and right hocks affected. Bursal lesions were seen in pigs from 8 to 28 weeks of age and prevalence increased with age. Also, the longer the period pigs spent in the pen, the more likely they were to have bursitis. After accounting for the effect of herd of origin, bedding which covered the whole pen (OR 0.11) or only the lying area (OR 0.29) was the most important factor which reduced the risk of bursitis. A wet slurry film in the dunging area (OR 1.67) and a difference between the solid area and the concrete slats greater than 3 cm (OR 3.11) were significantly associated with an increased risk of bursal lesions.     

Temperature and body weight affect fouling of pig pens

Fouling of the solid lying area in pig housing is undesirable for reasons of animal welfare, animal health, environmental pollution, and labor costs. In this study the influence of temperature on the excreting and lying behavior of growing-finishing pigs of different BW (25, 45, 65, 85, or 105 kg) was studied. Ten groups of 5 pigs were placed in partially slatted pens (60% solid concrete, 40% metal-slatted) in climate respiration chambers. After an adaptation period, temperatures were raised daily for 9 d. Results showed that above certain inflection temperatures (IT; mean 22.6 degrees C, SE = 0.78) the number of excretions (relative to the total number of excretions) on the solid floor increased with temperature (mean increase 9.7%/ degrees C, SE = 1.41). Below the IT, the number of excretions on the solid floor was low and not influenced by temperature (mean 13.2%, SE = 3.5). On average, the IT for excretion on the solid floor decreased with increasing BW, from approximately 25 degrees C at 25 kg to 20 degrees C at 100 kg of BW (P < 0.05). Increasing temperature also affected the pattern and postural lying. The temperature at which a maximum number of pigs lay on the slatted floor (i.e., the IT for lying) decreased from approximately 27 degrees C at 25 kg to 23 degrees C at 100 kg of BW (P < 0.001). At increasing temperatures, pigs lay more on their sides and less against other pigs (P < 0.001). Temperature affects lying and excreting behavior of growing-finishing pigs in partially slatted pens. Above certain IT, pen fouling increases linearly with temperature. Inflection temperatures decrease at increasing BW.     

母猪卧向行为学的观察

本文通过2个试验对母猪在分娩圈和分娩栏中的卧向行为进行了观察,试验一中, 选择10头大白(Yorkshire)经产母猪作为观察对象,试验二中分别选择10头大白(Yorkshire) 经产母猪和10头长白(Landrace)经产母猪作为观察对象。观察采用瞬时记录方法,每周观察 三次,隔日观察,每天上午、下午各观察一次,每次3 h,每次观察间隔5 min。观察中发现,母猪 卧向以向外为主。分娩栏(四周是栏杆)中的母猪以选择卧向外(向北)为主,其次是卧向内(向 南),卧向左和卧向右最少且差异不显著,上栏前和下栏后差异不显著。分娩圈(四周是墙壁)中 母猪以选择卧向外为主,卧向内最少,卧向左和卧向右差异不显著。长白母猪比大白母猪选择 卧向外的多,妊娠阶段比哺乳阶段选择卧向外的多。     

Tail-in-mouth Behaviour Among Weaner Pigs in Relation to Age,Gender and Group Composition Regarding Gender

Male pigs are significantly more often found to be tail-bitten at slaughter than are females. Age is also thought to be a crucial factor in relation to the ontogeny of tail-biting among slaughter pigs. Tail-in-mouth behaviour (TIM) among young pigs is probably the precursor of the damaging tail-biting in older pigs. Hence, this experiment aimed to elucidate the frequency of TIM in relation to gender, age and group composition regarding gender in weaner pigs. Pigs were reared in groups of 24 until 5 weeks of age and then divided into three groups: (A) eight female pigs, (B) eight castrated male pigs and (C) four female and four castrated male pigs (mixed pen). Observations was performed through video-recording 12 h per day, 1 day per week, for 4 consecutive weeks. The number of TIM events (counts) as well as the identity of the performer and the receiver of TIM were recorded. The results showed that the level of TIM activity in the single-gender pens was significantly lower than in the mixed pen (P<0.05). In the mixed pen, TIM tended to be more directed towards the opposite gender and female pigs tended to perform more TIM than the males. Finally, the frequency of TIM increased significantly with age in all three pens (P<0.01).     

Prepartum behavior of gilts in three farrowing environments

To determine effects of the farrowing environment on prepartum behavior, five gilts were monitored continuously for 48 h prior to parturition in each of three farrowing systems: 1) an open farrowing pen (2.1 x 1.5 m); 2) a turn-around farrowing pen, which allowed the gilt to turn around (2.4 m long; 1.8 m wide at back, .6 at front) and 3) a straight farrowing crate (sow zone = .6 x 2.1 m). Videorecords were summarized as three 16-h segments (Period A = 48 to 32 h before the first piglet was delivered, B = 32 to 16 h and C = 16 to 0 h) for analysis of activity over time. In all systems, frequencies of postural changes and oral-nasal activities directed at the floor or wall increased as farrowing was approached, the highest frequencies occurring in Period C. Respective times spent standing, sitting and engaged in oral-nasal activities directed at floor or wall also increased over time. Pawing occurred almost exclusively in Period C. Lying upright (ventral posture) occupied a greater portion of lying time as the gilt's activity increased over time, whereas feeding and drinking behaviors did not change over time. The only behavior affected by the experimental environments was the frequency of 90 degree turns. Gilts in both open and turn-around pens showed an increasing turning frequency over time, and they turned more often in the open pen than in the turn-around pen.(ABSTRACT TRUNCATED AT 250 WORDS)     

Space requirements of weaned pigs during a sixty-minute transport in summer

Currently, there are no trucking quality assurance recommendations for space allowance of weaned pigs during transport in the United States. The objective of this research was to establish a first estimate of the space requirements of weaned pigs during transport in summer based on measures of animal well-being. A commercial semi-trailer was fitted with compartments that provided 0.05, 0.06, and 0.07 m(2)/pig, which were replicated on the upper and lower deck, with a constant 100 pigs per compartment. Cameras were placed in each experimental compartment to record behaviors and postures of pigs during transport. The frequencies of standing, lying, sitting, standing/rearing on another pig, and lying/huddling on top of another pig were recorded using 1-min scan samples during the entire duration of transport. Blood samples were collected and BW and lesion scores recorded from 32 pigs per space allowance for physiological and immune measures before and after transport (n = 32 pigs/treatment). Pigs were transported for 60 +/- 5 min to the wean-to-finishing site using the same route for each replicate during summer (temperature: 28.4 +/- 1.2 degrees C and relative humidity: 59.8 +/- 4.4% within the trailer). Data were analyzed using the MIXED procedure (SAS Institute Inc., Cary, NC). Cortisol, hematocrit, blood urea nitrogen, total protein, albumin, aspartate aminotransferase, creatine kinase, and gamma-glutamyl transferase increased (P < 0.05) after transport regardless of space allowance. Plasma glucose and BW decreased (P < 0.05) after transport regardless of space allowance. Lesion scores increased (P < 0.001) after transport and were greater (P < 0.05) for barrows compared with gilts. The neutrophil to lymphocyte ratio was greater (P < 0.005) for pigs transported at 0.05 m(2)/pig compared with pigs transported at 0.06 and 0.07 m(2)/pig. Pigs transported at 0.05 m(2)/pig lay down less (P < 0.05) than pigs transported at 0.06 and 0.07 m(2)/pig between 30 and 60 min of transport. Greater neutrophil to lymphocyte ratio and less lying behavior performed by pigs transported at 0.05 m(2)/pig suggest that a minimum space allowance of 0.06 m(2)/pig was preferable when transporting weaned pigs for 60 min during summer in this study.     

Effect of floor area restriction upon performance, behavior and physiology of growing-finishing pigs

Fifteen groups of eight pigs were allocated .34, .68 or 1.01 m2 lying area per pig between 25 and 100 kg live weight. These values were chosen in accordance with Petherick's model to prevent all pigs from lying in full recumbency (.68 m2/pig) or on their sternum and belly (.34 m2/pig). Productivity decreased in the groups of pigs allowed only .34 m2/individual from 20 wk following the beginning of the experiment (70 to 80 kg). Behavioral changes were observed as early as 8 wk after the beginning of the experiment (60 to 70 kg). Severe area restriction increased time spent at the feeder. Aggression did not vary as a linear function of area allocation. Analysis of the main behavioral activities over a 10-h observation period revealed higher feeding time and lower social activity in pigs kept at .34 m2/pig. Sternum resting was more frequent than resting on the side when body weight reached 60 to 70 kg. Pigs that were submitted to the lower area allocation displayed enhanced resistance of their pituitary-adrenal axis to the dexamethasone suppression test and enhanced reactivity to adrenocorticotropic hormone injection. These findings demonstrate that behavioral and physiological responses are earlier and more sensitive indicators of adaptation to the environment than productivity.     

Behaviour and cleanliness of replacement dairy heifers housed in group pens with combined feeding–resting stalls

Abstract

This study was carried out in two commercial Norwegian dairy herds where the replacement heifers were kept in groups of 10 in pens with 6 conventional free-stalls and 5 combined stalls at the feed bunk. The stall cleanliness was better in the free-stalls than in the combined stalls (P?<?.01). Time spent lying was not affected by number of animals in the group (P?=?.20), but feeding synchrony (P?=?.05) and lying synchrony (<.001) were higher when there were six animals in the group. The heifers showed a clear preference for lying in the standard free-stalls and this was not affected by number of animals in the pen (P?=?.83). The results of this initial study indicate that a pen system with combined lying/feeding stalls and free-stalls offers a satisfactory lying comfort, apparently minimal competition over lying space and acceptable animal cleanliness.     

Evidence of phenotypic relationships among behavioral characteristics of individual pigs and performance

The objective of this research was to estimate phenotypic relationships among backtest scores (BTS), resident-intruder test scores (RIS), growth rate, LM area, and backfat in pigs. Little is known about the relationships among measures of behavioral characteristics of individual pigs and economically important traits. However, it may be expected that a pig's behavior affects its performance and that of its pen mates. The backtest was used in this experiment because it was previously shown to be a measure of individual stress-coping behavior and was related to lean gain. The resident-intruder test was used because it is a measure of a pig's tendency for aggressive behavior toward an unfamiliar pig. Each test was performed twice on pigs (n = 150) from 20 litters, and complete performance data was available on 140 pigs. Between 7 and 14 d of age, the backtest was performed by placing each pig in a supine position and gently restraining it for 60 s. The number of escape attempts (bouts of struggling) and total time spent struggling were recorded. The BTS was the summation of escape attempts during both tests. Resident intruder tests were assessed when pigs were between 30 and 50 d of age. A solid divider was placed in the resident pig's pen. The resident was placed alone on 1 side of the divider, away from its penmates. An intruder pig of the same sex and smaller size was then placed into the pen. When an attack was initiated by the resident, the pigs were immediately separated, the test was terminated, and a score of 1 was recorded. If no attack occurred by 5 min, the test was terminated and was given a score of zero. The cumulative score from both tests was the RIS. Dam effects influenced BTS (P < 0.01) and RIS (P < 0.03). Preweaning ADG of pigs with a BTS of 8 was 120 g greater than that of pigs with a BTS of 2. However, ADG from 20 to 76 d of age was 131 g greater in pigs with BTS = 2 than in pigs with BTS = 8. Lean gain of pigs with RIS = 2 was 25 g/d greater than in those with RIS = 0 or 1. This resulted in pigs with RIS = 2 having 1.6 kg more acceptable, standardized, fat-free lean. Conflicting results were found when relating the BTS to performance. However, with the RIS, greater aggression toward other pigs was associated with better performance. It was concluded that an unfavorable phenotypic relationship existed between RIS and lean growth.     

Effect of Early Rearing Environment and Tail Docking on Later Behaviour and Production in Fattening Pigs

Abstract

The effect of early rearing environment and tail docking on behaviour and production of fattening pigs was investigated in 576 cross-bred pigs. Half of the pigs came from four commercial pig units with tethered or otherwise confined sows, 4 weeks' weaning, little space per piglet and no use of straw. The other half of the pigs came from another four commercial units with loose-housed sows, 5-6 weeks' weaning and liberal space and use of straw. Half of the piglets from each of the units were tail docked. At an average weight of 33.5 kg the pigs were transferred to environmentally rich experimental pens where they stayed until slaughter at approx. 100 kg liveweight. On 8 observation days evenly distributed during the fattening period the pigs' use of the straw sections of the experimental pens was recorded as well as oral activities directed towards pen mates, including tail biting. The pigs' use of the pen's straw section declined significantly (p < 0.005) during the fattening period. The rearing environment had a significant effect on nibbling on pen mates (p <0.04) but not on tail biting. The nibbling on pen mates decreased (p < 0.02) while tail biting increased (p < 0.03) during the fattening period. The tail status had no significant effect on either of the two behavioural parameters. Neither rearing environment nor tail status influenced the relative growth rate. Pigs recruited from the “barren” environment showed an almost statistically significant higher incidence of chronic pleuritis (p = 0.069).     

Reaction of Calves to Two Flooring Materials Offered Simultaneously in One Pen

Now that group housing is replacing individual crates, so that calves can lie, stand and walk on the pen floor, the quality of the floor for group-housed calves has become the focus of attention. The reaction of two groups of four calves to a double area of floor made from two materials (wooden slats and synthetic slats with a rubber coating) was examined round the clock for 5 days. The calves were switched between pens twice, and in each case the 5 day observation period was repeated. In all three phases all calves spent significantly more time ( P <0.01) lying on the wooden floor: on average 656 min day -1 compared with 294 min day -1 on the synthetic floor. The time spent in the standing/walking position on both floors, occurrence of slip incidents and self-maintenance behaviour did not differ significantly between floors. The observations on use of the pen floor for lying and for standing/walking in combination with feeding, plus observations on fouling of the floors with excreta suggest that future pen design could be functionally divided into lying and walking/eating areas.     

The effects of R-salbutamol on behavior and physiology of finishing pigs

Salbutamol has potential for use as a repartioning agent in swine. The aims of this experiment were to determine effects of salbutamol on behavior and physiology of finishing pigs. The study used 192 pigs (88.8 +/- 0.9 kg of BW) housed in groups of 6 in 32 pens and assigned to 1 of 4 treatments: 1) control-0 mg/kg of salbutamol, 2) 2R--control diet with 2 mg/kg of the pure R-enantiomer of salbutamol, 3) 4R--control diet with 4 mg/kg of pure R-salbutamol, or 4) 8RS--control diet with 8 mg/kg of a 50:50 mixture of the R- and S-enantiomers. All diets were offered ad libitum for 4 wk. Salbutamol diets were replaced with control diets 24 to 48 h before slaughter. Behavioral responses to handling during weighing were recorded immediately before assignment to the treatments (wk 0) and at weekly intervals over the next 4-wk period. Behavioral and heart rate (HR) responses to a 10-min human presence test in the home pen were measured during wk 0, wk 1, and wk 3. Heart rate responses to a 36-min transportation were recorded. One pig from each pen had blood collected 4 times: during wk 0, 2, 4, and at exsanguination. Blood was analyzed for NEFA, creatine kinase, glucose, lactate, blood urea nitrogen, ammonia, insulin, cortisol, norepinephrine, and epinephrine. Data were analyzed using PROC GLM of SAS, with pen as the experimental unit. Treatment had no effect on time spent lying laterally, overall activity, or time spent alert. Treatment had no effect on handling measures (P > 0.05) or on behavioral responses to human presence (P > 0.05), with all pigs willing to spend similar amounts of time close to and touching the human. However, during the human presence test in wk 1 and wk 3, control pigs had HR around 10 peats per minute less (P < 0.05) than pigs in the other 3 treatments. During transport, overall HR were similar across treatments (P > 0.05). However, at certain 1-min time points, control pigs had greater HR than salbutamol-treated pigs (P < 0.05). There were no treatment differences in lactate, epinephrine, or norepinephrine concentrations at any point. During wk 4, control pigs had less creatine kinase (P < 0.02) and greater blood urea nitrogen (P < 0.005) compared with pigs fed all the salbutamol treatments. The home pen behavior, handling, human presence test, and transport results indicate that salbutamol-treated pigs do not show marked differences in home pen time budgets and behavioral and HR responses to handling and transportation compared with control pigs. Thus, salbutamol did not have a negative effect on finishing pig well-being during this study.     

Rolling behaviour of sows in relation to piglet crushing on sloped versus level floor pens

The study focused on the rolling behaviour of sows and the crushing of piglets by sows' rolling behaviour. The experiment examined the influence of sloped floor in loose housed farrowing pens on the rolling behaviour of sows and crushing of piglets. The experimental unit was made up of 24 pens. There were two experimental pen designs with piglet creep in the corner of the pen and piglet creep across the end of the pen, respectively. Both of the experimental pen designs had a 10% sloped floor in the sow's resting area. The two control pen designs were identical to the experimental pen designs, but with a level floor. The behaviour of 85 sows and their litters was continuously video recorded. Behavioural observations were made from birth of the first piglet and until 3 days after birth of the first piglet. Rolling behaviour of sows caused significantly more trapped piglets under the sow than lying down from standing (P = 0.04). Rolling behaviour caused 64% of the trapped piglets and lying down from standing caused 36% of the trapped piglets. Rolling from udder to side without protection trapped significantly more piglets than rolling from udder to side near slanted wall or piglet protection rails and rolling from side to udder (P < 0.001). With a certain pen design sloped floor reduced rolling from udder to side without protection (P = 0.007) and reduced the number of trapped piglets (P = 0.01), but results concerning lying behaviour showed that sloped floor pushed sows to rest on the level part of the floor. The results indicate that rolling behaviour that crushes piglets can be reduced, and sows prefer to lie on a level floor.     

The humane conditions of swine housing--a summary of various results

First a general survey about our ethological, endocrinological, histological and clinical investigations is given, carried out for more than 15 years with the objective to elaborate housing systems, which fulfill the requirements of the animals as well as the requirements of the producers. On one side free choice and accustoming experiments under standard conditions on the other side investigations on farms, to prove the results of the first as well as to prove how far new housing systems, which are in development in South Germany at present (housing of large groups, labor partitioning pig production), include a melioration in the sense of animal rights even when housing large numbers of animals. In the special part the following points are stressed: - endogenenously-implemented biphasic activity-rhythm of pigs and its influencing by light, room temperature, size of area and the inability of lying comfort. - different ranges of the influencing factors for the animals, in case of activity: 1. stimulus, 2. floor type, 3. size of area; in case of resting: 1. floor type, 2. stimulus, 3, size of area with a minimal size of area fitting to the different housing details in both cases - lying comfort depending on floor type, possibility to trample down faeces respectively to separate places of lying and faeces, room temperature - effects of stimulus - different minimal sizes of area. Results of the investigations in the agricultural practice of housing of piglets during and after the time of suckling and of fattened pigs are reported.(ABSTRACT TRUNCATED AT 250 WORDS)     

The effects of ractopamine on the behavior and physiology of finishing pigs

The objectives of this study were to examine the effects of ractopamine (RAC) on the behavior and physiology of pigs during handling and transport. Twenty-four groups of three gilts were randomly assigned to one of two treatments 4 wk before slaughter: finishing feed plus RAC (10 ppm) or finishing feed alone. Pigs were housed in the same building in adjacent pens with fully slatted floors and ad libitum access to feed and water. Behavioral time budgets were determined in six pens per treatment over a single 24-h period during each week. Behavioral responses of these pigs to routine handling and weighing were determined at the start of the trial and at the end of each week. Heart-rate responses to unfamiliar human presence were measured in all pigs and blood samples were taken from a single pig in each pen on different days during wk 4. At the end of wk 4, all pigs were transported for 22 min to processing. Heart rate was recorded from at least one pig per pen during transport and a postmortem blood sample was taken from those pigs that were previously sampled. During wk 1 and 2, RAC pigs spent more time active (P < 0.05), more time alert (P < 0.05), and less time lying in lateral recumbency (P < 0.05). They also spent more time at the feeder in wk 1 (P < 0.05). At the start of the trial, there were no differences in behavioral responses to handling. However, over each of the next 4 wk, fewer RAC pigs exited the home pen voluntarily, they took longer to remove from the home pen, longer to handle into the weighing scale and needed more pats, slaps, and pushes from the handler to enter the scales. At the end of wk 4, RAC pigs had higher heart rates in the presence of an unfamiliar human (P < 0.05) and during transport (P < 0.05), but not during loading and unloading. Also at the end of wk 4, RAC pigs had higher circulating catecholamine concentrations (P < 0.05) than control pigs. Circulating cortisol concentrations and cortisol responses to transport did not differ between treatments. The results show that ractopamine affected behavior, heart rate, and catecholamine profile of finishing pigs and made them more difficult to handle and potentially more susceptible to handling and transport stress.