Open Veterinary Journal, (2023), Vol. 13(11): 1436-1442

Original Research

10.5455/OVJ.2023.v13.i11.6

Evaluation of zootechnical parameters of piglets born and suckled from dams treated with a non-steroidal anti-inflammatory drug after farrowing

Paul Renaud^1*, David Reyero², Laura Pérez³, Albert Finestra³ and Erik Grandemange⁴

¹Vetoquinol N.-A. Inc., Lavaltrie, Canada

²Vetoquinol Especialidades Veterinarias S.A., Madrid, Spain

³Finestra Veterinarians Advisers S.L., Lerida, Spain

⁴Vetoquinol S.A., Magny-Vernois, France

*Corresponding Author: Paul Renaud. Vetoquinol N.-A. Inc., Lavaltrie, Canada. Email: paul.renaud [at] vetoquinol.com

Submitted: 06/07/2023 Accepted: 26/10/2023 Published: 30/11/2023

---

Abstract

Background: Farrowing is a precarious moment in pig production potentially associated with a wide range of ailments in sows and gilts, and often having a negative impact on pre-weaned piglet zootechnical performances.

Aim: To evaluate zootechnical parameters of piglets born and suckled from dams treated postpartum with tolfenamic acid (TA) at a commercial farm.

Methods: Dams were randomized to receive an intramuscular injection of 4% TA at 2 mg/kg body weight within 12 hours postpartum (TA group) or no inflammatory treatment (control group). Evaluated parameters included individual piglet live weight at birth (day 0); number of live piglets on day 2; mortality at weaning; and individual weight at weaning. Immunoglobulin G (IgG) transfer assessment was conducted in a subset of piglets stratified by suckling position.

Results: 81 dams and their litters were included (TA group: 20 sows, 21 gilts, 472 piglets; Control group: 20 sows, 20 gilts, 458 piglets), with IgG transfer assessment conducted in 80 piglets of 20 randomly selected dams (TA group: 40; Control group: 40). Piglet performances in the TA versus control groups, respectively, were: average daily gain 0.23 ± 0.06 versus 0.20 ± 0.06 kg (p < 0.05); weaned weight 6.32 ± 1.23 versus 5.50 ± 1.09 kg (p < 0.05); day 1 plasma IgG levels in piglets from gilts were 20.60 ± 3.78 versus 16.99 ± 4.23 µg/ml (p < 0.05); and mortality at weaning was 6.6% (31/472) versus 11.8% (54/458) (p < 0.05). The within-litter weaned weight variation in the TA group was not significant (p=0.11) at 6.50 ± 1.11 kg in the anterior suckling position versus 6.76 ± 1.01 kg in the posterior teat suckling positions, while the difference was significant (p < 0.05) in the control group, at 5.61 ± 0.68 kg versus 5.37 ± 0.75 kg, respectively.

Conclusion: Piglets in the TA group had statistically significant improved zootechnical performances, while their within-litter weaned weights did not differ significantly.

Keywords: NSAID, Tolfenamic acid, Within-litter, Weight, Variation.

---

Introduction

Farrowing is a precarious process that can potentially lead to a wide range of conditions in dams and their offspring (Mainau et al., 2016; Ison et al., 2017). These can include inflammatory conditions such as mastitis metritis agalactia (MMA) (Karst et al., 2021), endotoxemia (I.S.U., 2022), pain associated with parturition, and sore nipples, which can cause dams to become more aggressive and less receptive to suckling (Albáñez et al., 2019). These conditions are common, multifactorial, and may be difficult to diagnose under on-farm conditions (e.g., MMA). Thus, prophylactic treatment may be considered, including the use of non-steroidal anti-inflammatory drugs (NSAIDs). Postpartum treatment of the dam with an NSAID has been shown to improve dam welfare and productivity and reduce piglet mortality before weaning (Ison et al., 2017, Perez-Sala et al., 2022). Moreover, improved primary zootechnical performances [i.e., average daily gain (ADG) and weaned weights] have been demonstrated in piglets that suckled from dams treated with an NSAID peripartum (Mainau et al., 2016; Albáñez et al., 2019; Pérez-Sala et al., 2022).

Whether postpartum NSAID treatment of dams influences within-litter weaned weights is an area that warrants further investigation. Within-litter weaned weight variation is often associated with poor zootechnical performances such as increased piglet mortality, lower ADG, and high variability in weight at weaning and weight or age at slaughter (Milligan et al., 2002; Quesnel et al., 2008; Panzardi et al., 2013). It has been established that the birth weight of first-born piglets is usually higher than that of litter mates, and weaned weights of piglets suckling on/toward the posterior (caudal) teats are usually lower than that of piglets suckling on/toward the anterior (cranial) teats. However, it remains uncertain whether piglets maintain a suckling position until weaning (Skok and Škorjanc, 2013). This potentially adds to the complexity of within-litter weaned weight variation, which may suggest that issues other than suckling position may also have an influence.

We conducted a field trial to assess the zootechnical parameters of piglets born and suckled from sows and gilts treated postpartum with the NSAID, tolfenamic acid (TA). In addition, immunoglobulin G (IgG) transfer was assessed in selected piglets, which enabled the subsequent examination of within-litter weight variation. TA is approved throughout several countries and in many species including pigs, primarily as an adjunct treatment for MMA.

---

Materials and Methods

Trial site, herd, and experimental design

The field trial was conducted between August 26th and November 9th 2020 at a modern, high-performance commercial farrowing barn in Lleida, Spain. The barn holds 1,000 dams of PIC genetics and is managed in weekly band lots. In accordance with the standard operating procedures of the barn, sows and gilts were transferred to the farrowing room 7 days before the anticipated parturition date and kept in individual crates. Eligible dams were required to have a minimum of 13 “functional” teats, evaluated by palpation and visual assessment, and be assessed as healthy. During their gestation, dams were vaccinated against Escherichia coli and Clostridium perfringens (Porcilis^® ColiClos, MSD Animal Health, Salamanca, España) to provide passive immunity to their offspring. In addition, dams were also vaccinated against erysipelas, parvovirus, and leptospirosis (Eryseng^®, Hipra, Girona, España).

Health status was evaluated by measurement of body temperature, observation of demeanor, clinical/visual review, and assessment of any recent medical issues via health records. Included dams were randomly assigned to one of two groups: TA treatment or control group. Sows and gilts in the TA group received an intramuscular injection of 4% TA (Tolfine^®, Vetoquinol S.A., Magny Vernois cedex Lure, France) at a dosage of 2 mg/kg body weight within 12 hours postpartum (day 0), while the control group received no anti-inflammatory treatment. If the health status of the dam was assessed as meeting the inclusion criteria, she was randomly assigned to either group regardless of her body score. Consequently, body score notes were not taken. Weaning was performed 21 ± 3 days after farrowing. All included sows and gilts received the same proprietary commercial feed for lactating dams, and all management and husbandry processes were identical for both groups for the duration of the study.

Piglets were identified individually with ear tags (TA group: blue color numbered 501 to 1,000; Control group: yellow color numbered 0 to 500). Measured parameters in piglets included the number alive at day 2, mortality at weaning, individual live weight at birth (day 0), and individual weight at weaning.

A subset of piglets (n=80) was selected for IgG transfer assessment, including four piglets each from 10 randomly selected multiparous sows (TA group: 5, Control: 5) and four piglets each from 10 randomly selected gilts (TA group: 5; Control: 5). Of the four piglets taken from each dam, two were observed regularly and noted as suckling on, or toward, the posterior (caudal) teats, and two were observed regularly and noted as suckling on, or toward, the anterior (cranial) teats. Blood samples were collected from these piglets on days 1, 2, and 20 after birth. Blood samples were collected in Sarstedt S-Monovette^® vacuum collection tubes without anticoagulant and sent with ice packs on the day of collection to a nearby laboratory (LABOPAT, Carretera de Valladolid, La Lastrilla–Segovia, Spain) and analyzed using a swine IgG enzyme-linked immunosorbent assay quantitative test (Bethyl Laboratories). The suckling position was assessed in these piglets and validated everyday, until the final blood sampling on day 20. Other parameters recorded were the presence of any illness and rescue treatments if deemed necessary.

Postpartum to weaning management process

This study spanned several consecutive weekly band lots; therefore, an equal number of dams from the TA and control groups were included during each lot. According to the farm’s standard operating procedures, parturition monitoring was conducted several times per day at varying time points, starting early morning at approximately 7:00 and ending early evening at approximately 18:00. As previously mentioned, dams randomly assigned to the TA group were treated within 12 hours of farrowing (i.e., the birth of the last piglet). If farrowing began following the last monitoring the previous evening and the dam was observed as completely farrowed before 07h00 the next morning, those dams also received a TA treatment, respecting the “within 12 hours of farrowing” criteria stated in the protocol of this study. Farrowing intervention, which consisted of manual extraction, was conducted only when an interval of more than 45 minutes elapsed from the birth of the previous piglet. If fostering was considered necessary, piglets were reallocated to other dams in the same treatment group but remained traceable back to the original dam. None of the IgG-tested piglets were fostered. On day 2 or 3 of life, piglets were systematically treated with injectable gleptoferron and toltrazuril (Forceris^®, Ceva, Barcelona, España). On day 21, piglets were vaccinated against porcine circovirus type 2 and Mycoplasma hyopneumoniae (Circoflex^® and Micoflex^®, Boehringer Ingleheim, Barcelona, España).

Zootechnical performance parameters

The following piglet parameters were duly noted per protocol directives: 1) Date and time of farrowing to ensure that TA treatment was administered per the protocol directive within 12 hours of farrowing; 2) Number of piglets alive at day 2 to ascertain if there was a statistical difference between groups, as this could have bearing on the results of mortality at weaning; and 3) Individual live weight at birth and at weaning, which permitted the calculation of ADG from birth to weaning.

Statistical analyzes

Data were systematically collected and validated in a formatted standard Excel spreadsheet. Data analyzes were conducted in SAS/STAT 9.4 (SAS Institute Inc., Cary, NC) and SigmaPlot 14.0 software (Systat Software Inc., San Jose, CA). Descriptive statistics were used to describe the parity of dams; piglets alive at day 2 after farrowing and at weaning; and birth weight, weaned weight, and ADG until weaning in piglets. Continuous variables were expressed as means and standard deviations (SDs), and categorical variables were expressed as frequencies and percentages. The number of piglets alive on day 2 after farrowing and at weaning was compared between the treatment and control group using the Mann–Whitney Wilcoxon test. Piglet mortality at weaning was compared between treatment groups using Fisher’s exact test. Linear mixed models were used to compare piglet ADG until weaning and weaned weight between treatment groups, with treatment group, sex (male or female), dam’s parity (gilt or sow), and the treatment*sex, treatment*parity, and treatment*sex*parity interactions as fixed effects. The sow and gilt were introduced as random effects in the model. The effect of treatment on piglet IgG levels and the effect of treatment and suckling position on piglet weight at weaning and ADG were analyzed using linear mixed models in the subset of piglets selected for IgG transfer analysis. The udder suckling position was defined as position 1 for anterior (cranial) nipples and position 2 for posterior (caudal) nipples. For the effect of treatment on piglet IgG levels, linear mixed models were conducted with repeated measurements using treatment group, sex, mother's parity, day of measurement, suckling position of the piglet on the udder, and their interactions as fixed effects. The sow, gilt, and piglet were introduced as random effects in the model. As the treatment*day*parity interaction was statistically significant, linear mixed models with repeated measurements using treatment group, sex, suckling position of the piglet on the udder, and their interactions were used as fixed effects for each category of parity, at each day of measurement. The sow, gilt, and piglet were introduced as random effects in the model. The effect of treatment on the piglet’s weight at weaning and ADG were analyzed by means of a linear mixed model with treatment group, sex, dam’s parity, piglet’s weight at birth, and treatment, sex, and parity interactions as fixed effects. The sow was introduced as a random effect in the model. For all analyzes, p < 0.05 was regarded as statistically significant.

Ethical approval

For this field trial, an ethical review was conducted ex post facto (after the fact), under European standards by a duly registered ethical committee. The COMETA ethical committee of Vetoquinol S.A., registered in 2012 as CEA n°88 with the French Ministry of Higher Education and Research (Ministère de l’Enseignement Supérieur et de la Recherche), evaluated and approved the protocol and management (approval number 2022#11) during its November 2022 session. It was determined that the ethical rules, and primarily the 3Rs (replacement, reduction, and refinement) were considered and implemented. The tested product was used respecting the indications stated in the Summary of Product Characteristics. All animals were housed and maintained under good husbandry conditions and per the regulations in effect in Spain for commercial farms. This includes unobstructed access to clean and plentiful water, quality feed in quantities sufficient to meet nutritional requirements, and quality air as provided by a forced air ventilation system in the farrowing rooms, delivering an average ambient temperature of 25°C–26°C. Although piglets were handled a bit more than usual, all technical procedures were performed by experienced and trained staff, and it was concluded that the piglet’s quality of life was not impaired.

---

Results

Eighty-one dams were included in the study. The parity distribution by group is displayed in Table (1). Apart from the occasional case of suspected MMA, the overall health status of the included dams was assessed as good with no observable issues. A total of 930 piglets (TA group: 472; Control group: 458) were born from the included dams. Eighty piglets (TA group: 40; Control group: 40) were included in the IgG transfer analysis and 240 IgG serological analyzes were conducted.

Farrowing outcome

The mean number of live piglets 48 hours after farrowing did not differ (p=0.86; Table 2) between the TA treatment (11.24 ± 2.21) and control groups (11.00 ± 1.80). The mean birth weight was 1.56 ± 0.30 kg in the TA group and 1.50 ± 0.27 kg in the control group. Only four live piglets weighing <0.70 kg were registered in the live-born count.

Table 1. Parity distribution of dams.

Piglet zootechnical performances

ADG until weaning and average weaned weight was higher (p < 0.001) in piglets in the TA group, compared to the control group (ADG: 0.23 ± 0.06 vs. 0.20 ± 0.06; weaned weight: 6.32 ± 1.23 vs. 5.50 ± 1.09; Table 3). Mortality at weaning was lower (p < 0.05) in piglets from dams treated with TA (6.6%) compared to controls (11.8%). Day 1 plasma IgG levels were higher (p < 0.05) in piglets from gilts treated with TA (20.60 ± 3.78) compared to controls (16.99 ± 4.23). No other differences in IgG levels were observed between piglets from gilts or sows treated with TA compared to controls (Table 3).

Within-litter weaned weight analysis

In the subset of piglets selected for IgG transfer analysis who suckled on anterior teats, weaned weight (p=0.03) was significantly higher from dams treated with TA (6.50 ± 1.11) compared to controls (5.61 ± 0.68). Similar results were obtained when analyzes were restricted to piglets who suckled on posterior teats (p < 0.001; Table 4). Considering only piglets from dams treated with TA, there was no difference in weaned weight between those who suckled on anterior compared to posterior teats (p=0.20). However, in control piglets, weaned weight was higher (p < 0.05) in those who suckled on anterior (5.61 ± 0.68) compared to posterior teats (5.37 ± 0.75; Table 5).

---

Discussion

We conducted a randomized field trial to assess several zootechnical parameters in piglets born and suckled from dams treated with TA. The data collected display higher ADG and weaned weight, lower mortality at weaning, and within-litter weight uniformity in piglets born and suckled from dams who received postpartum treatment with TA when compared to the controls.

Previous trials have considered overall piglet ADG and weaned weights; however, the suckling position was not assessed (Mainau et al., 2016; Albáñez et al., 2019). Our study is unique in that the suckling position was noted in a subset of piglets, allowing the assessment of within-litter weight variances. The productivity of the dam and her offspring may be influenced by several variables, including within-litter weight variation at birth and change of within-litter weight during suckling (Damgaard et al., 2003). Several reasons have been proposed for these variations; increased litter size might negatively impact available in utero nutrients, thus smaller piglets may be at a competitive disadvantage compared to their larger litter mates (Damgaard et al., 2003; Zindove et al., 2013). Other production parameters to consider are the potential interaction between litter size and birth weight, as one may impact the other, and perhaps selective breeding, but reported to be of limited effect (Damgaard et al., 2003).

Table 2. Piglets alive per dam 48 hours after farrowing.

Table 3. Comparison of piglet zootechnical performances and IgG transfer levels between treatment groups.

Table 4. Comparison of weaned weight and ADG between treatment groups by suckling position for piglets selected for IgG transfer analysis (n=80).

Table 5. Comparison of weaned weight and ADG between suckling positions by treatment group for piglets selected for IgG transfer analysis (n=80).

It has been suggested that on-farm management can to some extent address weaned weight variation, primarily through flow strategies such as production scheduling of batches and age, along with cross fostering (Zindove et al., 2013). Nevertheless, slower-growing piglets within the same litter complicate production management, and several approaches to “physically” address the issue appear to have mitigated results (Zindove et al., 2013). A high variability in within-litter weaned weight may result in a lower weight at slaughter or delayed age to slaughter (Milligan et al., 2002; Quesnel et al., 2008; Panzardi et al., 2013). Weaned weight variation usually transcends over several weeks throughout the growing (or fattening) period and the weight at the time of sending the animals to market can thus also vary between animals. Market weight variation is less suitable from a commercial perspective because wide variation in carcass weight will affect derived products in terms of uniformity, which is less appreciated and potentially devalued in the market (Wolf et al., 2008; Campos et al., 2011; Zindove et al., 2013). To achieve relatively equal carcass weight, lower-weight pigs during fattening are sometimes kept longer to achieve a weight benchmark, but this entails a higher production cost in terms of increased feed consumption and overall maintenance (Campos et al., 2011). In addition, it is well established that lower-weight piglets within a litter have a lower survival rate as opposed to their heavier litter mates (Milligan et al., 2002; Zindove et al., 2013). The trend toward larger litter sizes in modern pig production worldwide appears to exacerbate the issue around within-litter weight variations. Thus, within-litter weight variation has important economic implications and represents an important area for improvement for swine producers. On the other hand, the reduction of pig weight variation improves pig flow production strategies and efficiencies, primarily in all-in all-out production schemes (Zindove et al., 2013).

Our study has many strengths. The trial was conducted at a single site and all dams/piglets were under the same conditions. Rigorous observations were conducted regarding individual weight, taken at birth and weaning, and suckling positions taken throughout the evaluation period (farrow to wean). Some limitations however need consideration. First, data on feed intake during lactation were not collected as part of this trial. The effect, however, is likely to be minimal since a post-farrowing NSAID treatment does not always produce differences in feed intake (Ison et al., 2017). Second, the cause of death in piglets was not noted although precise data were available on the number of piglet mortalities throughout the observation period (farrow to wean). The number of live piglets 48 hours after farrowing did not differ between groups. An autopsy was not carried out to assess the cause of death; however, randomization in this study likely mitigated biases in terms of one specific cause of mortality being allocated to a specific group.

In conclusion, data collected in this field trial display improved zootechnical performances, including within-litter weight uniformity, in piglets born and suckled from dams who received postpartum treatment with TA. Further research is warranted to broaden the scope to other potentially influential data points, for example, feed intake in lactating dams and how fostering may influence the data collected on mortality, ADG, and weaning weights.

---

Acknowledgments

The trial was conducted at a site under the supervision of Finestra Veterinarians Advisers S.L., 2540, Lerida, Spain. Some data discussed herein, and specifically data points related to weaned weights, ADG, IgG levels, and piglet mortality were presented in an abstract and poster at the 13th European Symposium of Porcine Health Management congress held in Budapest, Hungary, May 11–13, 2022. The medical writing support was provided by Dr Julia Granerod from Dr JGW Consulting Ltd.

Conflict of interest

Three of the five authors (Paul Renaud, David Reyero, Erik Grandemange) are currently employed by Vetoquinol. S.A., or one of its affiliates.

Funding

This study was funded by Vetoquinol. S.A.

Author contributions

Paul Renaud: Trial sponsor, protocol drafting, first and corresponding author of this manuscript. David Reyero: Protocol drafting, trial monitoring, data compilation, and manuscript review. Laura Pérez: Principal investigator and manuscript review. Albert Finestra: Clinical assessment, data collection, and manuscript review. Erik Grandemange: Protocol review, supervision of statistical analyzes, and manuscript review.

Data availability

The data that support the findings of this study are available from the corresponding author, upon reasonable request.

---

References

Albáñez, J.M., Renaud, P., Grandemange, E., Pablos-Hach, J.L. and Buntix, S.E. TA (Tolfine®, Vetoquinol) increases the weight gain of piglets born from gilts. In Proceedings of the European Symposium of Porcine Health Management, 2019, pp 184.

Campos, P.H.R.F., Silva, B.A.N., Donzele, J.L., Oliveira, R.F.M. and Knol, E.F. 2011. Effects of sow nutrition during gestation on within-litter birth weight variation: a review. Animal 6(5),797–806.

Damgaard, L.H., Rydhmer, L., Løvendahl, P. and Grandinson, K. 2003. Genetic parameters for within-litter variation in piglet birth weight and change in within-litter variation during suckling. J. Anim. Sci. 81(3), 604–610.

I.S.U. (College of Veterinary Medicine). 2022. Hypogalactia or mastitis, metritis, agalactia (MMA). Available via https://vetmed.iastate.edu/vdpam/FSVD/swine/index-diseases/hypogalactia (Accessed 31 March 2022)

Ison, S.H., Jarvis, S., Ashworth, C.J. and Rutherford, K.M.D. 2017. The effect of post-farrowing ketoprofen on sow feed intake, nursing behaviour and piglet performance. Livest. Sci. 202, 115–123.

Karst, N.A., Sidler, X. and Liesegang, A. 2021. Influence of mastitis metritis agalactia (MMA) on bone and fat. J. Anim. Physiol. Anim. Nutr. 105(Suppl.2), 138–146.

Mainau, E., Temple, D. and Manteca, X. 2016. Experimental study on the effect of oral meloxicam administration in sows on pre-weaning mortality and growth and immunoglobulin G transfer to piglets. Prev. Vet. Med. 126, 48–53.

Milligan, B.N., Fraser, D. and Kramer, D.L. 2002. Within-litter birth weight variation in the domestic pig and its relation to pre-weaning survival, weight gain, and variation in weaning weights. Livest. Prod. Sci. 76(1–2), 181–191.

Panzardi, A., Bernardi, M.L., Mellagi, A.P., Bierhals, T., Bortolozzo, F.P. and Wentz, I. 2013. Newborn piglet traits associated with survival and growth performance until weaning. Prev. Vet. Med. 110(2), 206–213.

Perez-Sala, L., Finestra-Uriol, A., Reyero, D., Grandemange, E., Merdy, O., Seux, N. and Renaud, P. Assessment of an NSAID administered to postpartum sows and gilts, to evaluate piglet zoo-technical performance and IgG transfer. In Proceedings of the European Symposium of Porcine Health Management, 2022, pp 131.

Quesnel, H., Brossard, L., Valancogne, A. and Quiniou, N. 2008. Influence of some sow characteristics on within-litter variation of piglet birth weight. Animal 2(12), 1842–1849.

Skok, J. and Škorjanc, D. 2013. Formation of teat order and estimation of piglets’ distribution along the mammary complex using mid-domain effect (MDE) model. Appl. Anim. Behav. Sci. 144, 39–45.

Wolf, J., Zakova, E. and Groeneveld, E. 2008. Within-litter variation of birth weight in hyperprolific Czech Large White sows and its relation to litter size traits, stillborn piglets and losses until weaning. Livest. Prod. Sci. 115, 195–205.

Zindove, T.J., Dzomba, E.F., Kanengoni, A.T. and Chimonyo, M. 2013. Effects of within-litter birth weight variation of piglets on performance at 3 weeks of age and at weaning in a Large White x Landrace sow herd. Livest. Sci. 115, 348–354.