Prairie Swine Centre

SEARCH

Localization of heat shock proteins and histopathological changes in the kidneys of transported pigs

Posted in: Welfare by admin on January 1, 2008 | No Comments

To demonstrate the expression of heat shock proteins (Hsps) in the kidney, 5 kinds of Hsps, namely, Hsp70, Hsp72, Hsp86, Hsp90, and Hsp27, were examined in pigs after 6-h-transports by using western blot analysis. All 5 Hsps were detected in the kidneys of both the transported and control pigs. Hsp expression in the control pigs indicated that Hsps have some physiological functions in addition to stress-response functions. With the exception of Hsp27, a significant reduction was observed in all the levels of Hsps in the kidneys of the transport-stressed pigs after 6 h of transport, particularly in the levels of Hsp70 and Hsp72, which belong to the HSP70 family; and Hsp86 and Hsp90, which belong to the HSP90 family. The results indicate that 6-htransports are not only related to renal pathological injury but also to a reduction in most of Hsp levels in the kidney. However, slight Hsp27 induction (Pb0.05) indicates that Hsps that undergo different changes following transportation stress are involved in different physiological functions. Whether the decreased amount of a certain Hsp may indicate damage and/or overuse and whether Hsps actually protect kidney tissue from such overuse remain to be elucidated.

For more information the full article can be found at http://www.journals.elsevierhealth.com/periodicals/livsci

Effect of driver and driving style on the stress responses of pigs during a short journey by trailer

Posted in: Welfare by admin on | No Comments

During transportation to an abattoir, pigs can be exposed to a variety of different stressors, eg temperature change, noise and sudden movements (acceleration, braking, cornering) (Lambooij & van Putten 1993). Vibration and unfamiliar movements of the vehicle might elicit a stress response (Dantzer & Mormède 1983; Geers et al 1994). The cardiovascular system is influenced by vibration, resulting in increased heart rate and blood pressure, and peripheral vasoconstriction (Randall et al 1995a). The stress caused by transport may adversely affect animal welfare and cause economic losses related to mortality, carcass damage, and decreased meat quality (Tarrant 1989; Warriss et al 1994). The motion of the floor surface in a transporter is dependent upon the vehicle’s suspension, load, floor rigidity, engine speed, transmission, road speed, road surface, wheel imbalance, etc. Aspects such as acceleration, braking, and cornering, which are under the control of the driver, affect an animal’s ability to maintain postural stability (Randall 1992; Randall et al 1995b). Since 1990 French drivers transporting pigs have undergone education (two-day sessions organised by ITP, Institut Technique de Porc, Paris, France) to help stress that good handling practices are important, not only from an economic point of view, but also in terms of public perception, ie the image consumers have of pig production. After these training sessions started, many slaughterhouses recorded decreased levels of skin damage (Chevillon 1998). The aim of this study was to investigate the possibility of reducing transported pigs’ stress levels by adjusting the driving style of different drivers. To this end, the effect of driver and driving style on pigs’ stress parameters such as behaviour, salivary cortisol concentrations, and heart rate variability was explored during a short journey. Additionally, the effect of different types of trailer acceleration (longitudinal, lateral, and vertical) on these variables was investigated. One hundred and thirty-five cross-bred pigs (Pietrain × Hypor) were transported in groups of five on a trailer towed by a jeep. Three different drivers transported the pigs using a normal, a quiet, and a wild driving style (the latter two in relation to their normal style). Driving style mainly had an effect on the longitudinal and lateral accelerations. Salivary cortisol increases were lowest for the wild driving style. The latter can be explained by the shorter duration of these journeys and not by the accelerations, thus it is our view that acceleration due to manoeuvring as opposed to acceleration due to overall speed should be avoided. Also, in practice, journeys should take as brief a time as possible. Increasing acceleration saw an increase in the proportion of pigs standing during the journey and a decrease in the proportion of pigs lying down. Measurements of variability in heart rate revealed that lateral acceleration was an important stressor for pigs. We concluded that, as driving style has an effect on different stress variables, increased driver awareness of the effects of their driving on the responses of pigs, would improve pig welfare.

For more information the full article can be found at http://www.tandfonline.com/loi/haaw20

Effects of pre-weaning exposure to a maze on stress responses in pigs at weaning and on subsequent performance in spatial and fear-related tests

Posted in: Welfare by admin on | No Comments

Learning, memory and regulation of the stress response are mediated by the hippocampus. Biologically
relevant hippocampal-dependent tasks that develop and integrate cognitive processing of this region may
not be available to piglets in some current production systems. Additionally, weaning piglets at less than two
weeks of age may make them particularly vulnerable to disruptions during cognitive development. We
measured the effects of a spatial maze task (MT) on the stress response of piglets at weaning (12 days of age)
and subsequent fear response (at 7 weeks of age). Twenty-seven pigs from four litters were assigned to one
of three treatments: maze task (MT), isolation control (IC), or control with sow (SC), then combined into
same sex groups with each treatment represented. Each group was tested four times per day from 5–11 days
of age. MT piglets navigated the MT in order to return to the home farrowing crate containing the sow and
litter. IC piglets were isolated for the same length of time taken for the MT piglet in their group to navigate
the MT. SC piglets controlled for handling and were returned to sow as MT entered the MT. Saliva was
collected immediately pre- and post-MT on day 11 to measure cortisol concentrations, which were lower
pre-MT (F(1, 8) = 5.65, P = 0.04). Weaning at 12 days of age increased cortisol concentrations 2 h postweaning
(F(4, 75) = 5.67, P < 0.001). When exposed to a modified Morris water maze (MWM), a
significant interaction of sex and treatment was found with MT males and IC females faster at solving
the MWM than male IC pigs (x2(2) = 9.14, P = 0.01). Lower cortisol concentrations were seen pre-water
maze versus post-water maze (F(1, 19) = 27.62, P < 0.001). At 50 days of age, fear response of pigs was
examined using three fear-related tests (open field test (OFT), novel object test (NOT), and human approach test (HAT), each consisting of 1 m acclimation and 4 m testing. In the HAT, MT animals had a tendency to
touch the unfamiliar person more quickly (F(2, 19) = 2.51, P = 0.10), and more times than animals in other
groups (F(2, 49) = 6.31, P = 0.008). MT may result in less fear of novel persons and ameliorate cognitive
deficits in male pigs, suggesting benefits of exposing young pigs to environments requiring spatial learning.

For more information the full article can be found at http://journals.elsevierhealth.com/periodicals/applan/issues

Effect of controlled alterations in maternal dietary retinol on foetal and neonatal retinol status and pregnancy outcome in pigs

Posted in: Welfare by admin on | No Comments

The objectives of this research were to determine whether alterations in maternal retinol levels during pregnancy programme later foetal and neonatal retinol status and organ development and to determine whether lowered retinol during early or late pregnancy has a greater effect on later development. In addition, the study provided an opportunity to determine whether such dietary modifications affect pregnancy outcomes such as birth weight and within-litter variation in piglet size. The data found indicated that, in the experimental population of animals studied, modest reductions in vitamin A status reduced the incidence of low birth weight piglets and within-litter variability in birth weight pose the intriguing possibility that alterations in dietary retinol could be used to improve pregnancy outcome. This possibility warrants further examination in a larger study.

For more information the full article can be found at http://www.journals.elsevierhealth.com/periodicals/livsci

The influence of age on the use of potential enrichment objects and synchronisation of behaviour of pigs

Posted in: Welfare by admin on | No Comments

The provision of environmental enrichment for pigs, in the form of objects or substrates, is a legal requirement throughout the EU. Environmental enrichment may be defined as an improvement in the welfare of an animal, as measured by psychological and physiological means, as a direct result of alterations in the animal’s environment (Newberry, 1995). Previous studies investigating the use of enrichment objects have tended to focus either on one age group or on the provision of one object throughout the animals’ lifetime (e.g. Beattie et al., 1995; Durrell et al., 1997; Hill et al., 1998; Lyons et al., 1995). This experiment therefore addressed the question of whether pigs of different ages require different types of enrichment objects in order to promote and maintain exploratory behaviour. Straw is generally recommended as suitable enrichment for pigs. However, over 85% of pigs in the EU are housed in slatted systems where it is impossible to use these materials spread over a wide area of solid floor. In these systems it is more typical to use alternatives such as hanging objects and, in such situations, enrichment becomes a single point within the pen rather than a diffuse source. This experiment aimed to identify how a pig’s age affected the extent and synchrony of use of different environmental enrichment materials, and how this use changed over time. In order to measure synchrony it is necessary to determine if more than one animal is performing the same behaviour at the same time, and also to determine whether or not this has simply occurred by chance (Engel and Lamprecht, 1997). Animals behaving independently of each other may still be performing the same behaviour, at the same time, and such chance occurrences need to be factored into calculations to determine the extent of true synchrony (Rook and Penning, 1991; Engel and Lamprecht, 1997). Ten diverse novel objects were each presented to three replicate litters of 3 weeks of age (sucklers) and three replicate groups of three animals of 5 (weaners) weeks and 13 (growers) weeks of age. Video recordings were made of the pigs’ behaviour over a period of 5 days and subsequently analysed for activity, inactivity and object directed behaviour of three animals per group on days 1 and 5. The observed performance of any given behaviour, when at least one other member of the group was also performing that behaviour, was compared with the probability that such concurrence occurred by chance and these results were used to calculate the degree of synchronisation. Gender had no effect on the duration of object use or approach latency. Growers displayed a shorter latency to approach the objects initially compared to sucklers and weaners. Sucklers used the objects to a much lesser extent than either the weaners or growers. Overall object use decreased between days 1 and 5. All of the age groups synchronised their behaviour to a much greater extent than expected by chance. The sucklers showed a higher degree of synchrony of activity and inactivity, but lower degree of synchrony for object directed behaviour, than the weaners and growers. The degree of synchronisation of object directed behaviour decreased over the 5-day period, irrespective of age. Significant correlations were found between the degree of synchrony and extent of object interaction only for the sucklers. Since pigs showed behavioural synchronisation, object availability should be considered when providing desirable enrichment in order to avoid excessive competition in larger commercial groups.

For more information the full article can be found at http://journals.elsevierhealth.com/periodicals/applan/issues

Music during play-time: Using context conditioning as a tool to improve welfare in piglets

Posted in: Welfare by admin on | No Comments

In this experiment, we investigated whether music can facilitate play behaviour in piglets after weaning, when that music had been presented preweaning as a contextual cue associated with access to a playroom. It was found that music replay post weaning does facilitate play behaviour in the Playroom group. The results also showed that playroom exposure preweaning reduced the number of injuries post weaning (W1, W2 and W3). In contrast with our expectations, music replay also facilitated play behaviour in the control group, although significantly less so than in the Playroom group.

For more information the full article can be found at http://journals.elsevierhealth.com/periodicals/applan/issues

Automatic detection of oestrus and health disorders using data from electronic sow feeders

Posted in: Welfare by admin on | No Comments

Eating behaviour is influenced by the onset of oestrus and diseases. For gilts, Friend (1973) reported a reduced
feed intake from 23.56±0.39 kg in weeks between successive oestrus to 19.90±0.38 kg in weeks when oestrus occurred. It is suggested that the effect of oestrus on appetite is caused by oestrogens. Furthermore, sows presenting health disorders will also modify their eating behaviour: a reduced feed intake is considered to be one of the first signs that an animal is ill. Therefore this study was designed to evaluate the potential of electronic sow feeder (ESF) measurements in detecting oestrus, lameness and other health disorders for group housed sows. The detection method suggested in this article shows a sensitivity that ranges from 39 to 75% according to the condition detected, i.e. oestrus, lameness or other health disorders. Results indicate that the detection method performs generally better than when the list of sows that have not eaten (provided by the ESF and only current tool available to the farmer) is used as alarms. The major
drawback of the detection method for the three conditions is a too high number of false alarms. Measurement of the
individual eating rank appears a relevant response variable, since it includes information on the group size.

For more information the full article can be found at http://www.journals.elsevierhealth.com/periodicals/livsci

Immunogenicity of porcine circovirus type 2 capsid protein targeting to different subcellular compartments

Posted in: Welfare by admin on | No Comments

Porcine circovirus type 2 (PCV2) is known to be associated with post-weaning multisystemic wasting syndrome (PMWS), an emerging disease in swine. The development of effective vaccines against PCV2 infection has been accepted as an important strategy in the prophylaxis of PMWS, and a DNA vaccine expressing the major immunogenic capsid (Cap) protein of PCV2 is considered to be a promising candidate. However, recent studies have revealed that interferons (IFNs), especially IFN-, can enhance the replication of PCV2, indicating that the high levels of IFN- induced by DNA vaccination seem to have potential deleterious effect on protective immunity. Strategies to improve the neutralizing antibody response and simultaneously decrease the IFN- response will facilitate the clinical application of DNA vaccines against PCV2. In the present study, four different DNA vaccine constructs encoding cytoplasmic (Cy-ORF2), secreted (Sc-ORF2), membrane-anchored (M-ORF2) or authentic nuclear-targeted (pc-ORF2) Cap protein were generated to evaluate the neutralizing antibody and IFN- responses in a mouse model. Although all four DNA constructs could elicit PCV2-specific humoral immune responses, mice inoculated with Sc-ORF2 developed a significantly higher level of neutralizing antibodies than those that received M-ORF2, pc-ORF2 or Cy-ORF2. Furthermore, mice immunized with Sc-ORF2 or M-ORF2 showed a significantly decreased or enhanced IFN- level, respectively, compared with those inoculated with pc-ORF2.With respect to neutralizing antibody and IFN- levels, Sc-ORF2 is a good candidate for DNA vaccination, and the secreted Cap protein appears to be an ideal antigen for use in development of vaccines against PCV2.

For more information the full article can be found at http://www.sciencedirect.com/science/journal/01615890

The effect of varying lengths of straw bedding on the behaviour of growing pigs

Posted in: Welfare by admin on | No Comments

Since January 2003, the provision of appropriate environmental enrichment to pigs of all ages has been a legal requirement in the EU. The Directive states that: ‘To enable proper investigation and manipulation activities, all pigs must have permanent access to a sufficient quantity of material such as straw, hay, wood, sawdust, mushroom compost, peat or a mixture of such which does not adversely affect the health of the animals’. European animal welfare legislation is built on the principle that all animals have intrinsic value. Animals should therefore be able to express species-specific behaviour. The pig has a propensity to express nosing, rooting and chewing behaviours as a result of both exploratory and feeding motivation (Fraser et al., 1991; Day et al., 1995, 1996b. When individuals are not able to express these behaviours in barren housing environments, the activity may be channeled towards inappropriate stimuli such as pen-mates (Lawrence et al., 1993). Straw has been reported to improve the welfare of pigs housed in barren environments, because it can be used as a recreational substrate, as a nutritional substrate and as a bedding material (Fraser et al., 1991; Arey and Bruce, 1993; Lyons et al., 1995; Van de Weerd et al., 2005b; Tuyttens, 2005). However, it is still not really clear how straw functions to modify behaviour and what it exactly is about straw that makes it so effective in occupying a pig (Van de Weerd, 2005a). Therefore it is important to gain knowledge about the properties of straw that are behaviourally rewarding for pigs (Day et al., 2001b). The acquisition of such knowledge can then be applied to facilitate the construction of environmental enrichment devices which meet the behavioural needs of pigs, whilst also being compatible with partly and fully slatted housing systems (Van de Weerd et al., 2003). The present study explored the efficacy of providing pigs with small quantities of chopped straw, as opposed to full-length straw, since the former material could be used in partly and fully slatted systems with less risk of blockage of the liquid slurry handling facilities. To investigate this, groups of growing pigs were exposed to treatments where the provision and length of straw varied. Twenty-four groups of growing pigs were exposed to one of four treatments (no straw bedding, full-length straw, half chopped straw, and fully chopped straw). Both pen-mate- and straw directed behaviours were recorded using ad libitum sampling. It was found that the length of straw affected both the quantity and quality of straw-directed behaviours. The provision of straw of any length reduced the occurrence of behaviours such as nosing other pigs, aggression and tail-biting compared with when straw was absent. Chopped straw increased the prevalence of behaviours such as licking and decreased the prevalence of behaviours such as picking, suggesting that pigs were not able to manipulate the chopped straw in the same way as full-length or half chopped straw. In addition, levels of tail-biting were higher in groups that were provided with chopped straw than in groups with full-length or half chopped straw. It is concluded that the use of chopped straw in growing/finishing housing systems, whilst better than no enrichment, is inadvisable because of the possibility that levels of adverse pen mate directed behaviours will increase.

For more information the full article can be found at http://journals.elsevierhealth.com/periodicals/applan/issues

Social discrimination of familiar conspecifics by juvenile pigs, Sus scrofa: Development of a non-invasive method to study the transmission of unimodal and bimodal cues between live stimuli

Posted in: Welfare by admin on | No Comments

A non-invasive method was developed to study the transmission of cues that are used in social
discrimination by pigs, Sus scrofa. We investigated the ability of juvenile pigs to discriminate between
pairs of familiar, similar-aged conspecifics in a Y-maze learning task, using either single or paired visual,
olfactory and auditory cues. The stimulus pigs (n = 12) were littermates that were familiar but unrelated to
the test pigs (n = 12). For the bimodal task, test pigs (four per treatment) were presented with cues of two
modalities: olfaction and vision (OV), vision and audition (AV), or audition and olfaction (AO).
Approaches to a pre-determined correct stimulus were rewarded with food in daily sessions, each of
10 consecutive trials. Three consecutive successful sessions of 8/10 correct choices (P = 0.00016)
fulfilled the criterion for starting the unimodal task, during which test pigs were given either olfactory,
visual or auditory cues only using the same success criterion. Eight pigs learnt the bimodal task (OV: 4,AV:
2,AO: 2) ofwhich six pigs subsequently completed the unimodal task successfully (O: 3,V: 2, A: 1). These
findings indicate that juvenile pigs have the cognitive capacity to discriminate between same-sex
littermates that are also familiar group-members in the absence of either visual, olfactory or auditory cues, and that some can use just one of these modalities. A larger-scale study is needed to determine the sensory hierarchy of social discrimination in pigs.

For more information the full article can be found at http://journals.elsevierhealth.com/periodicals/applan/issues

« Previous Page Next Page »

SEARCH

Industry Partners