Copyright is owned by the Author of the thesis. Permission is given for a copy to be downloaded by an individual for the purpose of research and private study only. The thesis may not be reproduced elsewhere without the permission of the Author.
The Productivity and Behaviour of Sows and Piglets Housed in Farrowing Pens with Temporary Crating or Farrowing Crates A thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science Kirsty Laura Chidgey 2016
Abstract Pen-based alternatives to farrowing crates have been researched for decades, in an effort to improve the welfare of farrowing and lactating sows. However, high piglet mortality, and a lack of commercially-relevant studies, has been a barrier to the acceptance of these systems in the pork industry. The purpose of this thesis was to compare the performance and behaviour of sows and piglets in farrowing pens with temporary crating, and in farrowing crates, in a commercial setting. In the first study, sows were housed in either a farrowing crate from 5 days pre-farrowing until weaning at 28 days; or in a pen where sows were crated from 3 days pre-farrowing until the 4 th day of lactation. The farrowing system (crate or pen) from which a sow was weaned had no effect on subsequent reproductive performance. However, pre-weaning piglet mortality was significantly higher in pens (10.2%) than in crates (6.1%). Sow and piglet behaviour was studied during the first 6 days post-farrowing in the second study. Sows in crates were confined throughout this observation period, whereas sows in pens were crated for days 1 3 post-farrowing and loose in the pen during days 4 6 post-farrowing. There was no difference between systems for the amount of time sows spent lying or standing during days 1 6, though sows in pens were more active once they were loose. Penned sows touched and investigated their piglets more once they were loose, compared to when they had been crated. There were few differences in piglet behaviour between farrowing systems. The influence of the birth and rearing location (crate or pen) on gilt behaviour was examined in the third study. Gilts were identified as having been born and reared in a i
farrowing crate or in a pen. Gilts and their piglets were observed during the first three days after giving birth in the system they were born and reared in, or in the system they were not born and reared in. Gilts born and reared in pens with temporary crating touched and vocalised towards their piglets more than gilts born and reared in farrowing crates, irrespective of whether they farrowed in a crate or a pen. This finding has implications for the transmission of maternal behaviour. The associations between sow behaviour, gilt behaviour and piglet behaviour were compared in farrowing crates and pens with temporary crating using the data of the second and third study. Some associations between sow and piglet behaviour changed when the sow was no longer confined in a crate. This finding could be the link that explains differences in the later behaviour of gilts that were reared in different systems. Future studies should focus on the transition period between a sow being crated and then let loose in a pen, to improve sow and piglet welfare in these systems. ii
Declarations This thesis contains no material that has been accepted for a degree or diploma by the University or any other institution. To the best of my knowledge no material previously published or written by another person has been used, except where acknowledgement has been made in the text. This thesis has been written with chapters formatted as papers for publication. Therefore there is some repetition of methods. Each chapter contains a full discussion and a complete list of references. The final general discussion chapter provides a succinct discussion of the key findings of this thesis. The published and submitted manuscripts include supervisors as co-authors; however for each chapter, I developed the experimental design, carried out data collection and performed data analysis, with the final manuscript being written with the direction of the co-authors. iii
Acknowledgements I would like to start by thanking my supervisors Professor Patrick Morel, Professor Kevin Stafford, and Ian Barugh. Thank you for your insight, guidance, encouragement and good humour throughout this PhD. The combination of perspectives that you each offered helped me approach problems from different angles, a habit I hope to continue. I owe a huge thanks to Waratah Farms Ltd. In particular to Bindi Ground, Martin Ellis and Torben Kristensen, who were integral to this research being possible. Thank you all for seeing the value in this project. Waratah Farms was a temporary home for me for a large part of this PhD and I thank everyone for making me welcome on farm, and in some cases, in your homes (thanks to the Ray family and to Torben and Jane for your hospitality). Thank you to the staff at Waratah Farms, particularly to Stuart Shaw and those in the farrowing department for being so accommodating of what I hope was only a slight and occasional disruption to your hard work. Your patience and assistance was much appreciated. New Zealand Pork provided the funding for this project, for which I am very grateful. I also received the Massey University Alumni Doctoral Completion Bursary. Dr Mariusz Skorupski kindly provided access to EliteHerd software, which was much appreciated. Thanks to the New Zealand pig farmers I ve met along the way for your passionate opinions and the illuminating discussions that I have enjoyed throughout my pig-related studies. iv
Finally, I would like to thank my own family for their encouragement and support, and for lending an ear when I needed it. That also includes the Sneddons, of course. To Nick, thank you for your never ending optimism, insight and encouragement all while working on your own PhD. v
The Productivity and Behaviour of Sows and Piglets Housed in Farrowing Pens with Temporary Crating or Farrowing Crates PhD Thesis, Massey University, New Zealand vi
Table of Contents Abstract... i Declarations... iii Acknowledgements... iv Table of Contents... vii List of Tables... ix List of Figures... xi List of Abbreviations... xii Chapter 1... 1 General introduction... 1 Chapter 2... 9 Literature Review... 9 Chapter 3... 55 Sow and piglet productivity and sow reproductive performance in farrowing pens with temporary crating or farrowing crates on a commercial New Zealand pig farm... 55 Chapter 4... 83 Observations of sows and piglets housed in farrowing pens with temporary crating or farrowing crates on a commercial farm... 83 Chapter 5... 109 The performance and behaviour of gilts and their piglets is influenced by whether they were born and reared in farrowing crates or farrowing pens.... 109 vii
Chapter 6... 139 Sow and piglet behavioural associations in farrowing pens with temporary crating or farrowing crates... 139 Chapter 7... 171 General discussion... 171 Appendix One... 192 viii
List of Tables Table 2.1. Summary of piglet mortality in farrowing crates and farrowing pens... 36 Table 3.1. A comparison of litter performance parameters between sows housed in farrowing pens or farrowing crates (LSMEAN ±SE).... 67 Table 3.2. A comparison of subsequent reproductive performance between sows housed in farrowing pens or farrowing crates (LSMEAN ±SE).... 71 Table 3.3. The % of piglets that died before or after day 4 in farrowing pens and conventional farrowing crates, classified by reason for death.... 72 Table 4.1. Parameters recorded during observations of sows and piglets.... 91 Table 4.2. Sow behaviour and posture during days 1 6 post-farrowing (% back transformed from Logit Lsmean).... 94 Table 4.3. Piglet behaviour and location during days 1 6 post-farrowing (% back transformed from Logit Lsmean).... 96 Table 5.1. Parameters recorded during observations of gilts and piglets.... 117 Table 5.2. A comparison of litter performance parameters between gilts that were born and reared in pens or crates and farrowed in pens or crates (Lsmean ± SE).... 122 Table 5.3. Observations of gilt behaviour and posture during the first three days postfarrowing, Logit least square means ± SE (back transformed %)... 124 Table 6.1. Parameters recorded during observations of gilts and piglets.... 148 Table 6.2. Differences between sow and piglet behaviour correlations in period 1 and period 2 in crates (N = 15) and pens (N = 16).... 151 ix
Table 6.3. Associations between sow posture and piglet directed behaviour and the behaviour of piglets in crates (N = 15) and pens (N = 16) in period 1 and period 2 (Lsmean %).... 153 Table 6.4. Associations between pen and crate directed behaviour by sows and the behaviour of piglets in crates (N = 15) and pens (N = 16) in period 1 and period 2 (Lsmean %).... 156 Table 6.6. Associations between gilt posture and piglet directed behaviour and the behaviour of piglets during days 1 3 post-farrowing (Lsmean %).... 159 Table 6.7. Associations between pen and crate directed behaviour by gilts and the behaviour of piglets during days 1 3 post-farrowing (Lsmean %).... 161 x
List of Figures Figure 2.1. Simple loose pen... 33 Figure 2.2. Designed loose pen... 34 Figure 2.3. Two stage pen... 35 Figure 3.1. The farrowing pen design.... 61 Figure 3.2. Comparison of pigs weaned per litter per batch (N = 14 batches of sows) in conventional farrowing crates and combination pens (LSMEAN ± SE). ** P<0.01.... 68 Figure 3.3. Empty weight and weaning weight of sows housed in either a combination pen or conventional farrowing crate (LSMEAN ± SE).... 70 xi
List of Abbreviations NAWAC = National Animal Welfare Advisory Committee ACTH = Adrenocorticotrophic hormone HPA = Hypothalamic Pituitary Adrenal (axis) ABN = Arched-back nursing LG = Licking and grooming C = Farrowing crate P = Pen with temporary crating PWM = Pre-weaning piglet mortality rate, expressed as a percentage PGF 2α = Prostaglandin F 2α WSI = Wean to service interval ADG = Average daily gain (birth to weaning) AM1 = Observation session between 0800 0845 AM2 = Observation session between 0920 1100 PM1 = Observation session between 1230 1445 PM2 = Observation session between 1520 1600 CC = A gilt born and reared in a crate, which farrowed in a crate CP = A gilt born and reared in a crate, which farrowed in a pen PC = A gilt born and reared in a pen, which farrowed in crate PP = A gilt born and reared in a pen, which farrowed in a pen C1 = Crate, Period 1 (days 1 3 post-farrowing) C2 = Crate, Period 2 (days 4 6 post-farrowing) P1 = Pen, Period 1 (days 1 3 post-farrowing) P2 =Pen, Period 2 (days 4 6 post-farrowing) P day = P value for the main effect of the day of observation P system = P value for the main effect of the farrowing system (crate or pen with temporary crating) P born = P value for the main effect of the location where a gilt was born and reared (crate or pen with temporary crating) P farrow = P value for the main effect of the location where a gilt farrowed (crate or pen with temporary crating) xii