Evaluation of Dietary Phytogenics on Growth Performance and Carcass Characteristics of Pigs during the Growing-Finishing Phase

Phytogenic feed additives are plant-derived compounds incorporated into animal feed with the goal of improving animal health and performance. Previous research with the use of phytogenics during the growing-finishing phase suggested that the combination of two essential oil mixtures elicited improved ADFI, HCW, and carcass ADG compared to a regimen without the use of any additive. To further confirm these observations, a total of 317 pigs (DNA 600 × 241, initially 49.3 kg BW) were used in an 87-d trial to determine the effects of two essential oil mixtures tested individually, and in combination on growth performance and carcass characteristics of growing-finishing pigs from 49 to 130 kg. Pens of 9 or 10 mixed sex pigs were allotted by BW and randomly assigned to 1 of 4 dietary treatments with 8 replications per treatment. Pigs were fed a nutritional program with 4 dietary phases with the same treatments fed in all 4 phases. Experimental treatments included a control diet with no feed additives or the control with 0.02% essential oil mixture 1 (EOM 1) containing caraway, garlic, thyme, and cinnamon; 0.013% essential oil mixture 2 (EOM 2) containing oregano, citrus, and anise; and lastly the combination of 0.02% EOM1 and 0.013% EOM2 (EOM 1+2). At d 87, pigs were transported to a packing plant for processing and carcass data collection. There was no evidence for treatment differences for overall ADG, ADFI, or G:F. Similarly, there was no evidence for treatment differences in HCW, carcass yield, backfat, loin depth or percentage lean. In summary, inclusion of these phytogenic feed additives did not influence growth or carcass performance. Responses to feeding phytogenic additives have not been consistent among research studies. Consequently, more evidence is needed to confirm if beneficial effects on pig performance are consistently realized before these products are included in swine diets.

		Feed additive				P-values
	Control	EOM 1	EOM 2	EOM 1+2	SEM	E1XE2	EOM 1
ADG, g	912	908	918	912	7.0	0.908	0.466
ADFI, g	2,833	2,783	2,828	2,842	34.6	0.333	0.572
G:F	0.322	0.327	0.325	0.321	0.0033	0.193	0.913
Final BW, kg	129.4	128.4	129.7	129.1	1.01	0.817	0.242
HCW, kg	101.0	99.8	101.0	101.3	0.83	0.465	0.465
Carcass yield, %	74.8	75.0	74.8	74.9	0.31	0.948	0.594

E1xE2 Interaction between EOM 1 and EOM 2.

EOM 2 P-values for ADG, ADFI, G:F, Final BW, HCW, and carcass yield were 0.532, 0.415, 0.579, 0.524, 0.224, and 0.881, respectively.