Leena Anil

Effect of lameness on sow longevity.

OBJECTIVE To analyze the association of lameness and performance variables on sow longevity by use of time-to-event analysis. DESIGN Cohort study. ANIMALS 674 sows from a commercial breeding herd. PROCEDURES A lameness assessment was performed on each sow. Data on farrowing performance and longevity were collected for the sows during 3 or fewer parities from the database of the herd during 2005 and 2006. The association of risk factors with sow longevity within 350 days after lameness assessment was analyzed via Cox regression analysis. Pigs per day, total production days, and survival at 350 days after lameness evaluation were compared between lame and nonlame sows. RESULTS Numbers of preweaning baby pig deaths, stillborn pigs, and mummified pigs were negatively associated with sow longevity within 350 days after lameness assessment. A higher number of pigs born alive and younger parity of sows were protective. Lame sows had a higher risk (1.710 times as high) of removal from the herd within 350 days after lameness assessment. The number of pigs born alive per day, survival of sows at 350 days, and total number of days in the herd were lower in lame sows. CONCLUSIONS AND CLINICAL RELEVANCE Results of this study indicated significant differences in the survivability of lame and nonlame sows in a commercial herd. Parity and farrowing performance variables were factors influencing sow longevity in this herd. Producers need to minimize sow lameness and remove lame sows from a herd early (when treatment is not an option) to minimize economic loss.

Pain Detection and Amelioration in Animals on the Farm: Issues and Options

Pain in nonhuman animals is a difficult concept to identify and measure. This article briefly describes the consequences of pain in animals on the farm and explains the reasons for the minimal use of analgesics in farmed animals. Pain can have implications for both animal welfare and economics. The reasons for a low use of analgesics in farmed animals include the lack of recognition of animal pain owing to the apparent lack of anthropomorphically identifiable behavioral changes, concern over human food safety, and lack of research efforts to develop safe analgesics for farm use. Treatment cost relative to the benefits expected is another hindering factor. Interventions to minimize pain must begin with developing objective and practical measures for pain identification and measurement at the farm level. A suggested use of a combination of different behavioral and physiological indicators would help to identify pain in animals. To facilitate continued usage of the methodologies on the farm it also is necessary to evaluate the economic implication of the pain alleviation intervention.

Relationship between postural behaviour and gestation stall dimensions in relation to sow size

The extent to which the size of the gestation stall, relative to the size of the sow, affects the normal basic postural behavioural needs of sows like standing, sitting and lying was assessed using 25 sows randomly selected from four farms. The postural behaviour of the animals was recorded using a time-lapse video recorder. The relationships of duration of postures, time taken for various postural changes and frequency of postural changes with stall measurements in relation to sow measurements were analysed. Negative correlations (P 0.05). The time taken to change from a standing to lying posture was negatively correlated (P<0.05) with stall length relative to animal length. Similar correlations (P<0.05) were noted between stall width relative animal breadth and the duration of postural change from standing to sitting and from sitting to standing. Stall width relative to animal breadth was negatively related to the frequency of postural change from standing to sitting (P<0.05). The results suggested that the freedom of movement of pregnant sows in stalls could be improved by a little increase in the space allowance within the stall.

Effects of allometric space allowance and weight group composition on grower-finisher pigs

The average daily gain (ADG; kg d-1), pen efficiency (PE; kg ADG m-2 floor space) and welfare indicators (injury levels, salivary cortisol concentrations and behaviour) of grower-finisher pigs were evaluated in groups of 19 barrows, at four levels of floor space allowances calculated mathematically (area = k × BW0.667) using a constant k, (with values 0.027, 0.031, 0.034, and 0.037) for a mean final market weight of 116 kg and in two levels of group weight composition (uniform and varying weights – based on uniformity and variation of body weights of pigs within a pen at the beginning of the experiment). The corresponding space allowances (m2 pig-1) at the market weight of 116 kg were 0.64 (SA0.64), 0.74 (SA0.74), 0.81 (SA0.81), and 0.88 (SA0.88). The data were analyzed using repeated measure ANOVAs and independent sample T tests. The pigs in SA0.64 had a lower ADG (0.859 ± 0.017), spent a lower proportion of time lying in preferred areas (55.22 ± 1.644) and had higher total injury scores (4.581 ± 0.139) ...

Analysis of periparturient risk factors affecting sow longevity in breeding herds

The association of periparturient risk factors with sow longevity and the validity of sow removal decisions made during the periparturient period were analyzed. Data pertaining to 2066 sows from a commercial breeding herd from the US Midwest were used in this study. The likelihood of removal from the herd within 35 d post-farrowing decreased with a younger parity, the absence of lameness or other health problems, a higher lactation feed intake (LFI) and a greater number of live-born piglets (P < 0.05 for all). A greater number of piglets born alive, the absence of lameness and a younger parity lowered (P < 0.05 for all) the likelihood of removal of sows from the herd before the next parity. The number of piglets born alive was higher (P < 0.05) among sows without any health problems during the previous periparturient period. A greater (P < 0.05) number of sows that were retained without any health problems during the periparturient period farrowed. More sows (P < 0.05) retained with health problems during...

A path analysis of the factors associated with seasonal variation of breeding failure in sows

Data pertaining to 868 904 services of sows from 58 Canadian herds for the period 1999 to 2003 were retrieved from the PigCHAMP data share database and subjected to path analysis to evaluate the effect of number of inseminations per service (1 and >1), wean to service interval (WSI ≤ 5 d and > 5 d) and parity (parity 1, parities 2 to 5 and parity > 5) on the seasonality of breeding failure. Population attributable fraction (PAF) was calculated to determine the contribution of each risk factor. Overall breeding failure proportions were 23.5 and 20.9% in summer and other months, respectively. The likelihood of breeding failure was higher when sows were artificially inseminated (AI) only once, and 6 and 5% of breeding failures in the summer and other months, respectively, were attributable to single insemination. The likelihood of breeding failure was 1.5 and 1.4 times higher when WSI was > 5 d in the summer and other months, respectively, and 14% of breeding failure in summer was attributable to increase in...

Effects of different levels of feed intake during four short periods of gestation and housing systems on sows and litter performance

The current study investigated the effects of different levels of feed intake during 4 short periods of gestation and of housing systems on sow and litter performance. A total of 255 multiparous sows were allotted to 1-4 dietary treatments using a randomized complete block design blocking by initial body weight (BW), backfat (BF) and parity. Sows were housed either in individual stalls (n=129) or group pens (n=126) with 55 sows in each pen with electronic sow feeder during gestation. All sows were fed one common corn-soybean meal-based diet with the amount of 1.0×maintenance energy level of feed intake (106×BW0.75) throughout gestation except 4 periods of 7 d when dietary treatments were imposed on day 27, 55, 83 and 97 of gestation. During the 4 periods, sows were fed 1 of 4 different levels of feed intake: 0.5, 1.0, 1.5 and 2.0×maintenance energy level (0.5M, 1.0M, 1.5M and 2.0M, respectively). Results showed that both BW gain and BF change during gestation for sows on 1.5M (49.7kg and 3.1mm, respectively) and 2.0M (52.5kg and 3.7mm, respectively) levels of feed intake were significantly (P<0.01) greater than sows on 0.5M (26.1kg and -0.1mm, respectively) and 1.0M (35.6kg and 0.1, respectively) levels of feed intake. In contrast, lactation weight gain for sows on 1.5M (3.3kg) and 2.0M (3.4kg) levels of feed intake during 4 short periods of gestation were significantly (P<0.01) less than sows on 0.5M (18.4kg) and 1.0M (11.4kg) levels of feed intake during 4 short periods of gestation, whereas BF loss during lactation for sows on 1.5M (-3.6mm) level of feed intake during 4 short periods of gestation were significantly (P=0.03) higher than sows on 1.0M (-2.1mm) level of feed intake during 4 short periods of gestation. Additionally, average daily feed intake during lactation for sows on 0.5M (6.6kg/d) level of feed intake during gestation tended (P=0.06) to be greater than sows on 2.0M (5.9kg/d) level of feed intake. There were no differences (P>0.1) among 4 levels of feed intake in terms of numbers of total born and weaning piglets. However, both piglet weight at birth (1.46, 1.52, 1.53 and 1.51kg for piglets from sows on 0.5M, 1.0M, 1.5M and 2.0M levels of feed intake during gestation, respectively) and at weaning (6.37, 6.55, 6.64 and 6.38kg for piglets from sows on 0.5M, 1.0M, 1.5M and 2.0M levels of feed intake during gestation, respectively) were maximized at 1.5M level of feed intake. Sows housed in group pens had greater (P<0.01) net BW gain (24.7 vs. 19.2kg) from day 27 of gestation to weaning compared with sows housed in individual stalls. However, there were no differences (P>0.1) between the 2 housing systems in terms of litter size and piglet weight at birth and at weaning. In conclusion, increasing levels of feed intake during 4 short periods of gestation increased BW and BF gain during gestation and led to less BW gain and more BF loss during lactation. Piglet weight at birth and at weaning was maximized at 1.5M level of feed intake. However, housing systems did not affect reproductive performance. Group pen housing system may be beneficial in terms of increased overall BW gain during gestation and lactation.