Efficacy of the feed additive consisting of Lactiplantibacillus plantarum (formerly Lactobacillus plantarum) CECT 8350 and Limosilactobacillus reuteri (formerly Lactobacillus reuteri) CECT 8700 (AQ02) for suckling piglets (Aquilon Cyl S.L.)

1.2. Additional information

The additive is a preparation containing Lactiplantibacillus plantarum CECT 8350 and Limosilactobacillus reuteri CECT 8700. The additive is currently not authorised in the EU. The EFSA FEEDAP Panel issued an opinion on the safety and efficacy of this product when used in feed for suckling piglets (EFSA FEEDAP Panel, 2021). The FEEDAP Panel could not conclude on the efficacy of the additive for the target species.

2.2. Methodologies

The approach followed by the FEEDAP Panel to assess the efficacy of Lactiplantibacillus plantarum CECT 8350 and Limosilactobacillus reuteri CECT 8700 (AQ02) is in line with the principles laid down in Regulation (EC) No 429/2008 ⁷ and the relevant guidance document: Guidance on the assessment of the efficacy of feed additives (EFSA FEEDAP Panel, 2018).

3.1. Efficacy

In the current application, to support the efficacy in the target species, the applicant has provided a trial aimed at assessing the effect of the additive on the zootechnical performance of the piglets during the suckling period (up to 28 days of life); ⁸ the study also included the monitoring of the animals during 1 week after weaning (up to 35 days of life). However, the Panel did not consider the data of the post‐weaning period as evidence of the efficacy of AQ02 due to the following experimental design limitations: short duration of the monitoring period, high number of veterinary treatments and inappropriate experimental unit used for the statistical analysis.

Twenty Landrace × Large White sows were distributed in two homogeneous groups in terms of body condition (according to back fat) and parity (same number of primiparous and multiparous sows within each group; four primiparous/group). The animals were placed in two contiguous parity rooms with 10 pens each (5 litters per treatment in each room). After the first colostrum intake and within 24 h after farrowing, the piglets were individually administered a single oral dose either of a sterile saline solution without (control) or with the additive suspended at 25 mg/mL (correspondent to a total of 1 × 10⁹ CFU/piglet). From farrowing to weaning, each litter remained in the farrowing pen with the respective mother. Cross‐fostering after farrowing was not performed. The piglets were offered a creep feed from day 8 to 20 of age, and a pre‐starter feed from day 21 to 28.

The mortality and health status of the animals were monitored daily, and the most likely cause of death, reason for culling and use of veterinary treatments recorded. In terms of zootechnical parameters, all piglets were individually weighed at birth (day 1) and weaning (day 28), and the average daily weight gain calculated. The litter feed intake was measured weekly since the start of the administration.

Regarding health parameters, general clinical signs and need for antibiotic or other veterinary treatments were registered and compared among treatments. Mortality was reported. Other parameters were measured, such as faecal consistency and microbiota, which did not significantly differ between groups by the end of the suckling period.

The zootechnical performance data were analysed with a generalised linear model, including the treatment and the parity of the sow as fixed effects and the piglets' initial body weight as a covariate. The significance level was set at 0.05.

The individual piglet was the experimental unit used in the statistical model to evaluate the zootechnical performance of the piglets. The Panel notes that the experimental unit used was incorrect, and the litter/sow should have been considered instead. Despite that, the results did not show any significant differences between the groups for any zootechnical parameter recorded during the lactation period (body weight, total feed intake, average daily gain, mortality) (Table 2). Considering the absolute values recorded for these parameters, the Panel considers unlikely that the use of litter as the experimental unit would modify the results.