PhD candidate in clinical veterinary sciences, specialising in pig behaviour and pig welfare. Passionate about animal science and contributing to improvement in farm animal welfare.
Simple Summary: Floors with a series of gaps to allow pig manure to pass through (slatted floors)... more Simple Summary: Floors with a series of gaps to allow pig manure to pass through (slatted floors) are common in the pig industry as they enable the efficient management of pig waste. Pigs need enrichment materials to occupy them and to reduce harmful behaviours like tail biting. Loose materials are problematic in slatted systems because they can block up the slats and slurry pumps. This study aimed to establish if it is possible to rear pigs with undocked tails in a fully slatted system with compatible enrichment, while keeping tail biting at a manageable level and to investigate how important the variation of enrichment is. The results showed that although some tail biting occurred, the level was low with only mild lesions observed. Only 1 out of 96 pigs sustained severe tail damage (portion of tail bitten off). Pigs receiving a more varied enrichment tended to have lower tail lesion scores than pigs continuously presented with the same enrichment. This study showed that an optimal quantity and quality of slat-compatible enrichment provision can reduce the risk of tail biting in undocked pigs in fully slatted systems. The important role of adequate environmental enrichment provision in fulfilling pigs' biological needs cannot be overemphasised. Abstract: In fully slatted systems, tail biting is difficult to manage when pigs' tails are not docked because loose enrichment material can obstruct slurry systems. This pilot study sought to determine: a) whether intact-tailed pigs can be reared with a manageable level of tail biting by using multiple slat-compatible enrichment; b) whether a variation of enrichment has an effect; and c) whether pigs show a preference in enrichment use. Ninety-six undocked pigs were given the same enrichment items from one week after birth until weaning. At weaning, four different combinations of 8 enrichment items were utilized based on predefined characteristics. These were randomly assigned to 8 pens (n = 12 pigs/pen). Four pens had the same combination (SAME) from assignment and four pens switched combinations every two weeks (SWITCH). Individual lesion scores, interactions with the enrichment, and harmful behaviours were recorded. The average tail score during the experiment was low (0.93 ± 0.02). Only one pig in a SAME pen had a severely bitten tail (partly amputated). The overall level of interaction with enrichment did not decline over time. Pigs interacted with a rack of loose material most frequently (p < 0.001). The study showed promising results for rearing undocked pigs on fully slatted floors using slat-compatible enrichment.
Simple Summary: Tail biting is an unpredictable and costly damaging behaviour among pigs that cau... more Simple Summary: Tail biting is an unpredictable and costly damaging behaviour among pigs that causes painful injuries. A major concern of the industry is how to control tail biting outbreaks when they occur. We aimed to evaluate the effectiveness of three different interventions to overcome tail biting outbreaks: removing biter, removing victim, or providing three ropes; deployed in random order. If the first intervention failed, a second was used, and then a third if that also failed. Data were collected from two studies in which a total of 1248 pigs (96 pens) were housed on fully-slatted floors. Forty tail biting outbreaks were recorded, of which twenty were resolved using only one intervention. Eighty percent of all outbreaks were controlled within three intervention steps. Adding ropes was the fastest way to stop an outbreak but did not stop more than the other strategies; success depended more on the proportion of tail biting pigs in the pen than the intervention used. Removed victims and biters were successfully reintroduced back to the original group, following set rules. This is crucial to reduce the need for space and renders the interventions applicable on commercial farms. It is promising that most outbreaks were overcome using these cost-effective measures. Abstract: Solutions are needed to keep pigs under commercial conditions without tail biting outbreaks (TBOs). However, as TBOs are inevitable, even in well managed farms, it is crucial to know how to manage TBOs when they occur. We evaluated the effectiveness of multi-step intervention protocols to control TBOs. Across 96 pens (1248 undocked pigs) managed on fully-slatted floors, 40 TBOs were recorded (≥3 out of 12-14 pigs with fresh tail wounds). When an outbreak was identified, either the biters or the victims were removed, or enrichment (three ropes) was added. If the intervention failed, another intervention was randomly used until all three interventions had been deployed once. Fifty percent of TBOs were controlled after one intervention, 30% after 2-3 interventions, and 20% remained uncontrolled. A high proportion of biters/victims per pen reduced intervention success more so than the type of intervention. When only one intervention was used, adding ropes was the fastest method to overcome TBOs. Removed biters and victims were successfully reintroduced within 14 days back to their home pens. In conclusion, 80% of TBOs were successfully controlled within 18.4 ± 1.7 days on average using one or multiple cost-effective intervention strategies.
The provision of manipulable material to pigs is a legal requirement to ensure their good welfare... more The provision of manipulable material to pigs is a legal requirement to ensure their good welfare. Loose straw is edible, chewable, investigable and manipulable, and has been proven to be effective in reducing abnormal behaviour. However, it is incompatible with slatted systems and therefore not a viable option for many intensive units. Thus, there is a need to identify enrichment materials that are as effective as loose straw and compatible with slatted floors. This study investigated the viability of using compressed straw blocks on a commercial farm in terms of cost and effectiveness in reducing biting relative to plastic hanging toys. A total of 880 slaughter pigs were used, among which half (n = 440, 8 groups) were provided with commercial pig toys (TOY) and the other half (n = 440, 8 groups) were provided compressed straw blocks (STRAW BLOCK). Animals were separated according to sex to investigate whether there was a higher propensity to tail and ear bite depending on sex. Pigs were monitored from weaning to slaughter, with tails being examined post scalding and any condemnations recorded at the abattoir. Throughout their life, the tails and ears of all pigs were examined individually, and behavioural observations of each pig group were conducted fortnightly. Salivary cortisol was also obtained from a subsample of pigs from each group every fortnight to monitor stress levels. The highest straw usage was recorded in the second weaner stage (39 to 67 days after weaning). Enrichment type or sex had no effect on tail lesion scores or cold carcass weight recorded at the abattoir. There was also no effect of enrichment type or sex on body, tail, or ear lesion scores during either the weaner (0 to 39 days after weaning) or finisher stage (67 to145 days after weaning). Female pigs showed more biting behaviour than males, and female pigs that were provided STRAW BLOCK performed better than those provided TOY. In both the weaner and finisher accommodation, more instances of interaction were recorded with TOY pens as enrichment than with STRAW BLOCK, but the interaction duration was not recorded. There was no effect of sex on either stage. More instances of aggression were observed with the TOY than with STRAW BLOCK in the weaner stage (P < 0.05). Enrichment type or sex had no effect on cortisol levels. Thus, relative to plastic hanging toys, compressed straw blocks provided in this manner did not benefit pig welfare.
Simple Summary: Floors with a series of gaps to allow pig manure to pass through (slatted floors)... more Simple Summary: Floors with a series of gaps to allow pig manure to pass through (slatted floors) are common in the pig industry as they enable the efficient management of pig waste. Pigs need enrichment materials to occupy them and to reduce harmful behaviours like tail biting. Loose materials are problematic in slatted systems because they can block up the slats and slurry pumps. This study aimed to establish if it is possible to rear pigs with undocked tails in a fully slatted system with compatible enrichment, while keeping tail biting at a manageable level and to investigate how important the variation of enrichment is. The results showed that although some tail biting occurred, the level was low with only mild lesions observed. Only 1 out of 96 pigs sustained severe tail damage (portion of tail bitten off). Pigs receiving a more varied enrichment tended to have lower tail lesion scores than pigs continuously presented with the same enrichment. This study showed that an optimal quantity and quality of slat-compatible enrichment provision can reduce the risk of tail biting in undocked pigs in fully slatted systems. The important role of adequate environmental enrichment provision in fulfilling pigs' biological needs cannot be overemphasised. Abstract: In fully slatted systems, tail biting is difficult to manage when pigs' tails are not docked because loose enrichment material can obstruct slurry systems. This pilot study sought to determine: a) whether intact-tailed pigs can be reared with a manageable level of tail biting by using multiple slat-compatible enrichment; b) whether a variation of enrichment has an effect; and c) whether pigs show a preference in enrichment use. Ninety-six undocked pigs were given the same enrichment items from one week after birth until weaning. At weaning, four different combinations of 8 enrichment items were utilized based on predefined characteristics. These were randomly assigned to 8 pens (n = 12 pigs/pen). Four pens had the same combination (SAME) from assignment and four pens switched combinations every two weeks (SWITCH). Individual lesion scores, interactions with the enrichment, and harmful behaviours were recorded. The average tail score during the experiment was low (0.93 ± 0.02). Only one pig in a SAME pen had a severely bitten tail (partly amputated). The overall level of interaction with enrichment did not decline over time. Pigs interacted with a rack of loose material most frequently (p < 0.001). The study showed promising results for rearing undocked pigs on fully slatted floors using slat-compatible enrichment.
Simple Summary: Tail biting is an unpredictable and costly damaging behaviour among pigs that cau... more Simple Summary: Tail biting is an unpredictable and costly damaging behaviour among pigs that causes painful injuries. A major concern of the industry is how to control tail biting outbreaks when they occur. We aimed to evaluate the effectiveness of three different interventions to overcome tail biting outbreaks: removing biter, removing victim, or providing three ropes; deployed in random order. If the first intervention failed, a second was used, and then a third if that also failed. Data were collected from two studies in which a total of 1248 pigs (96 pens) were housed on fully-slatted floors. Forty tail biting outbreaks were recorded, of which twenty were resolved using only one intervention. Eighty percent of all outbreaks were controlled within three intervention steps. Adding ropes was the fastest way to stop an outbreak but did not stop more than the other strategies; success depended more on the proportion of tail biting pigs in the pen than the intervention used. Removed victims and biters were successfully reintroduced back to the original group, following set rules. This is crucial to reduce the need for space and renders the interventions applicable on commercial farms. It is promising that most outbreaks were overcome using these cost-effective measures. Abstract: Solutions are needed to keep pigs under commercial conditions without tail biting outbreaks (TBOs). However, as TBOs are inevitable, even in well managed farms, it is crucial to know how to manage TBOs when they occur. We evaluated the effectiveness of multi-step intervention protocols to control TBOs. Across 96 pens (1248 undocked pigs) managed on fully-slatted floors, 40 TBOs were recorded (≥3 out of 12-14 pigs with fresh tail wounds). When an outbreak was identified, either the biters or the victims were removed, or enrichment (three ropes) was added. If the intervention failed, another intervention was randomly used until all three interventions had been deployed once. Fifty percent of TBOs were controlled after one intervention, 30% after 2-3 interventions, and 20% remained uncontrolled. A high proportion of biters/victims per pen reduced intervention success more so than the type of intervention. When only one intervention was used, adding ropes was the fastest method to overcome TBOs. Removed biters and victims were successfully reintroduced within 14 days back to their home pens. In conclusion, 80% of TBOs were successfully controlled within 18.4 ± 1.7 days on average using one or multiple cost-effective intervention strategies.
The provision of manipulable material to pigs is a legal requirement to ensure their good welfare... more The provision of manipulable material to pigs is a legal requirement to ensure their good welfare. Loose straw is edible, chewable, investigable and manipulable, and has been proven to be effective in reducing abnormal behaviour. However, it is incompatible with slatted systems and therefore not a viable option for many intensive units. Thus, there is a need to identify enrichment materials that are as effective as loose straw and compatible with slatted floors. This study investigated the viability of using compressed straw blocks on a commercial farm in terms of cost and effectiveness in reducing biting relative to plastic hanging toys. A total of 880 slaughter pigs were used, among which half (n = 440, 8 groups) were provided with commercial pig toys (TOY) and the other half (n = 440, 8 groups) were provided compressed straw blocks (STRAW BLOCK). Animals were separated according to sex to investigate whether there was a higher propensity to tail and ear bite depending on sex. Pigs were monitored from weaning to slaughter, with tails being examined post scalding and any condemnations recorded at the abattoir. Throughout their life, the tails and ears of all pigs were examined individually, and behavioural observations of each pig group were conducted fortnightly. Salivary cortisol was also obtained from a subsample of pigs from each group every fortnight to monitor stress levels. The highest straw usage was recorded in the second weaner stage (39 to 67 days after weaning). Enrichment type or sex had no effect on tail lesion scores or cold carcass weight recorded at the abattoir. There was also no effect of enrichment type or sex on body, tail, or ear lesion scores during either the weaner (0 to 39 days after weaning) or finisher stage (67 to145 days after weaning). Female pigs showed more biting behaviour than males, and female pigs that were provided STRAW BLOCK performed better than those provided TOY. In both the weaner and finisher accommodation, more instances of interaction were recorded with TOY pens as enrichment than with STRAW BLOCK, but the interaction duration was not recorded. There was no effect of sex on either stage. More instances of aggression were observed with the TOY than with STRAW BLOCK in the weaner stage (P < 0.05). Enrichment type or sex had no effect on cortisol levels. Thus, relative to plastic hanging toys, compressed straw blocks provided in this manner did not benefit pig welfare.
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