Table 4. Effect of cooling systems on blood metabolites in 35 days old gestating sows exposed to heat stress during early pregnancy1)
| Items | HS(n = 8) | AC(n = 8) | WC(n = 8) | SEM |
| Total protein (g/L) | 7.99 | 7.63 | 8.08 | 0.099 |
| BUN (mg/dL) | 8.00b | 7.25b | 10.25a | 0.430 |
| AST (U/L) | 161.75 | 110.25 | 141.75 | 32.423 |
| ALT (U/L) | 31.88 | 34.13 | 32.38 | 2.119 |
| NEFA (umol/L) | 65.75 | 64.13 | 65.50 | 13.089 |
| T3 (ng/dL) | 71.66b | 95.68a | 89.33ab | 4.703 |
| T4 (ug/dL) | 4.27 | 5.23 | 4.74 | 0.213 |
Animals were subjected to heat stress for early stage (0 to 35 d) of gestation.
Means with different superscript in same row differ below 0.05 of p-value.
HS, without any cooling; AC, air cooling system; WC, water-drip cooling system; BUN, blood urea nitrogen; AST, aspartate aminotransferase; ALT, alanine aminotransferase; NEFA, non-ester fatty acids; T3, triiodothyronine; T4, thyroxine.