Growth performance
At the end of the study duration, the livability (%) was observed,
i.e., day 40
th, was highest (97.50%) in G4 as compared with G1 (92.50%), G2 (90.00%) and G3 (95.00%). The mean body weight (g) in the finisher phase,
i.e., day 40, increased by 2.73% and 2.46% in G2 and G4, respectively, compared with G1. These findings indicated that SFP at the supplementation level of 150 g/ton was the best regarding body weight improvement effects compared with G1 and G3. FCR was improved in all the SFP-added groups,
i.e., G2, G3 and G4, compared with G1. Results of FCR showed that birds in G2, G3 and G4 consumed 8 g, 12 g and 26 g less feed per unit body weight gain, respectively, compared with G1. EEF was increased by 4.75%, 8.17% and 18.79% in G2, G3 and G4, compared with G1. These results inferred G4 is the best regarding feed utilization efficiency. The overall growth performance of birds in G4 was better than all other groups (Table 4).
Quality parameters
RTC
The relative RTC was increased in all the SFP supplemented groups,
i.e., G2, G3 and G4, compared with G1. However, G4 performed on par with G2 and G3 regarding RTC (%) improvement effects (Table 4).
Litter quality
There was a wet litter observed in G1. However, in SFP supplemented groups,
i.e., G2, G3 and G4, no wet litters were observed (Table 5). These findings inferred that SFP performance at the 150 g/ton supplementation level was on par with competitor products regarding litter quality maintenance.
Health
The liver marker enzyme SGPT decreased in G4 compared with G1 (Table 6). Except for changes in biochemical parameters of all the groups, including the control group, no effect of product supplementation was recorded.
Serum IBD antibody titer
IBD antibody titer is represented in Table 7 (Vaccination index-VI). These findings revealed that the VI of IBD titer was increased by 0.97% in G4 compared with G1. This increase could be attributed to better immune-modulatory effects of SFP (150 g/ton) than CP-I and CP-II on B and T lymphocytes, phagocytic cells, CD+ cells and other immune organs, which are involved in augmenting the immune response and effective in maintaining the broiler chicken health status.
Gut health
The mean gut health score results revealed a significant (
p<.05) reduction in the total gut health score of G3 and G4 compared with G1 (Table 8 and Fig 1a, 1b, 1c and 1d). These findings implied that SFP at the supplementation levels of 150 g/ton would play a key role in gut health improvement compared with competitive products.
Mean bacterial enteritis
The mean bacterial enteritis and intestinal histomorphometry scores exhibited by G1, G2, G3 and G4 were 6.80, 7.70, 3.00, 2.3 and 7.62, 7.85, 7.17 and 8.65, respectively (Table 9). These findings indicated that SFP supplementation at 150 g/ton provided better protection against bacterial enteritis infection and played a pivotal role in enhancing intestinal health as compared to the control group.
Intestinal histomorphometry
The ratio of villi: Crypt was calculated as 7.62, 7.85, 7.17 and 8.65 in by G1, G2, G3 and G4, respectively (Table 9 and Fig 2). Present study findings implied that supplementation of SFP at 150 g/ton caused an increment in the ratio of villi: crypt indicating that SFP supplementation plays a pivotal role in improving intestinal health as compared to control and other groups through the proliferation of the intestinal surface area and intestinal villus height.
Gut microflora
The analysis results of the fecal flora of individual organisms
viz. Bacillus sp., Lactobacillus sp., Bifidobacterium sp. and Clostridium sp. are depicted in Fig 3a and Fig 3b. The results implied that the counts of pathogens revealed a significant reduction in G4,
i.e., SFP (150 g/ton) formulation when compared to the control group. The probiotic counts were compared with the competitors. Supplementation with SFP (150 g/ton) formulation showed reduced pathogens loads.
The study suggests that SFP at 150 g/ton can improve production performance, protect against bacterial enteritis and enhance gut health in Cobb 430 broiler chickens. This can be attributed to individual herbal ingredients and probiotics like
B. coagulans,
B. subtilis,
B. polymyxa, B
. pumilus and yeast β-glucan. Research indicates that combining probiotics and prebiotics can yield greater benefits than either alone (
Adil and Magray, 2012;
Hasanpur et al., 2013; Madej et al., 2015). Additionally, multi-strain probiotics have been shown to improve production performance, gut health and overall health status in Cobb 430 broiler chickens
(Mokhtari et al., 2010; Razieh et al., 2015).
SFP supplementation likely enhances bacterial enteritis protection and intestinal health by promoting increased villi height and crypt depth. β-glucans possess both probiotic and immunostimulatory properties
(Chen et al., 2016; Mitsou et al., 2010; Lam and Cheung, 2013); influencing leukocyte activity
(Chae et al., 2006; Volman et al., 2008). Furthermore,
Z. officinale extracts exhibit antimicrobial activity against common poultry pathogens like
Escherichia coli,
Staphylococcus aureus and
Klebsiella spp.
Dieumou et al., 2009; Bhattarai et al., 2018).
Studies demonstrate that dietary SFP supplementation with
Z. officinale and
C. longa improves production performance in poultry
(Mohamed et al., 2012; Ademola et al., 2009; Onimisi et al., 2005). These ingredients stimulate salivary and gastric gland secretions, potentially reducing microbial load and aiding gut digestion (
Yamauchi, 2009). Additionally,
Z. officinale enhances intestinal function by boosting enzyme activities like intestinal and pancreatic lipase (
Srinivasan, 2016). Moreover, supplementing with
Z. officinale has been shown to improve dressing percentage and potentially boost immunity due to its antioxidant and natural aromatic compounds like gingerol and shogaols (
Eltazi, 2014;
Azhir et al., 2012; Nidaullah et al., 2010; Khan et al., 2012). Curcumin, another component of SFP, exhibits positive effects on nutrient metabolism, reduces oocyst shedding and lesions and protects the gut by enhancing host humoral immunity
(Rajput et al., 2013; Srinivasan, 2016;
Khalafalla et al., 2011 and
Kim et al., 2013).