Evaluation of dietary electrolyte balance on nursery pig performance1

Abstract

Increasing dietary electrolyte balance (dEB) has been reported to linearly improve pig growth performance up to approximately 200 to 250 mEq/kg. However, recent data indicate that increasing dietary dEB reduced growth performance of nursery pigs. To attempt to solve this discrepancy, a total of 2,880 weanling pigs (327 × 1,050; PIC, Hendersonville, TN; 5.2 kg initial BW) were used to determine the effects of increasing dEB on nursery pig performance. Pens of pigs were blocked by BW and gender on arrival. Within block, pens were randomly assigned to one of four dietary treatments. There were 30 pigs per pen (60 pigs per double-sided feeder) and 12 replications (feeder) per treatment. Dietary treatments were fed in two phases. The phase 1 diet was based on corn–soybean meal, contained dried distillers grains with soblubles (DDGS), spray-dried whey, and specialty protein sources, and was fed from days 0 to 8. The phase 2 (days 8 to 21) diets contained corn, soybean meal, and DDGS with reduced amounts of specialty protein sources. Dietary electrolyte balance was determined using the following equation: dEB = [(Na × 434.98) + (K × 255.74) − (Cl × 282.06)] mEq/kg. The dEB of the four phase 1 diets were 84, 137, 190, and 243 mEq/kg, and dEB of the four phase 2 diets were 29, 86, 143, and 199 mEq/kg. After feeding experimental diets for 21 day, a common, commercial corn–soybean meal diet was fed to all pigs from days 21 to 35 and contained a dEB of 257 mEq/kg. During days 0 to 8, increasing dEB increased (quadratic, P < 0.05) ADG, ADFI, and G:F. From days 8 to 21, increasing dEB improved ADG (quadratic, P = 0.022) and ADFI (linear, P = 0.001), resulting in an improvement (quadratic, P = 0.001) in G:F. Overall (days 0 to 21), increasing dEB increased (linear, P < 0.05) ADG, ADFI, and improved (quadratic, P < 0.001) G:F. When a common diet was fed to all pigs from days 21 to 35, there was a linear reduction in ADG and G:F with increasing dietary dEB, but no effect of ADFI. For the overall nursery period (days 0 to 35), increasing dEB from days 0 to 21 increased (linear, P < 0.001) ADG and final BW, which was the result of increased (quadratic, P < 0.05) G:F and marginally greater (linear, P = 0.077) ADFI. In conclusion, increasing dietary dEB up to 243 and 199 mEq/kg (in phases 1 and 2, respectively) in nursery diets improved growth performance of weanling pigs.

Effects and interaction of dietary electrolyte balance and citric acid on growth performance, intestinal histomorphology, digestive enzyme activity and nutrient transporters expression of weaned piglets

“…NRC (2012) reported that the optimal dEB for pigs is approximately 250 mEq/kg. Jones et al (2019) observed that reduced levels of nursery dietary dEB in phase one (84, 137, 190, and 243 mEq/kg) and phase 2 (29, 86, 143, and 199 mEq/kg) resulted in poorer growth of weanling piglets. In this study, the insignificant growth differences may have resulted from the number of test days.…”

“…At weaning, young pigs are exposed to psychosocial and physical stressors accompanied by marked changes in gastrointestinal physiology, microbiology and immunology, which may result in poor growth performance and increased mortality (Hampson, 1986; Heo et al, 2012; Hu et al, 2013; Pluske et al, 1997). Dietary ion content is known to alter the acid–base balance, osmotic pressure and nutrient metabolism in animals (Dersjantli et al, 2002; Guzmán‐Pino et al, 2015; Seifter & Chang, 2017), which can influence growth performance (Jones et al, 2019). Calcium (from limestone), phosphorus (from calcium phosphate), and sodium and chloride (from salt and sodium bicarbonate) are often added to the diet to satisfy animal growth requirements (NRC, 2012).…”

“…Xin et al (2017) suggested that weaned pigs obtained optimal growth performance when fed diets with dEB in the range of 166 to 250 mEq/kg. Additionally, Jones et al (2019) found that increasing dietary dEB up to 243 and 199 mEq/kg, in phases 1 and 2, respectively, in nursery diets improved growth performance of weanling pigs. Nevertheless, the optimal dEB for pigs in the literature is inconsistent, and a study demonstrated that piglets fed single diets with low (from –16 to 133 mEq/kg) rather than high (from 269 to 388 mEq/kg) dEB levels showed optimal growth rates (Guzmán‐Pino et al, 2015).…”

“…NRC (2012) reported that the optimal dEB for pigs is approximately 250 mEq/kg. Jones et al (2019) observed that reduced levels of nursery dietary dEB in phase one (84, 137, 190, and 243 Ionized Ca concentration in the blood decreased as dEB was increased in diets, with lower ionized Ca values on the 250 mEq/kg diet compared to the −50 mEq/kg diet. This result can be related to the decrease in the bone turnover in case of a more alkaline diet.…”

Effects of electrolyte balance on intestinal barrier, amino acid metabolism, and mTORC1 signaling pathway in piglets fed low-protein diets

“…(2017) concluded that weaned pigs achieved the optimal growth rate when fed diets containing 166 to 250 mEq/kg dEB. Jones et al. (2019) observed that in stages 1 and 2, the optimal dEB for weaned piglets was 243 and 199 mEq/kg, respectively.…”