Effect of timing of prepartum vaccination relative to pen change with an acidogenic diet on lying time and metabolic profile in Holstein dairy cows.

The objective was to assess the effect of prepartum vaccination timing relative to pen change with an acidogenic diet at 28 or 21 d before expected parturition (dpp) on lying time (LT), prepartum serum energy status (glucose, IGF-1, and nonesterified fatty acids), urine pH, and serum Ca at calving in pregnant Holstein dairy cows. Pregnant multiparous Holstein cows (n = 308) from 1 large dairy herd were randomly allocated into 1 of 3 treatment groups at 35 ± 3 dpp as follows: (1) vaccination at 28 dpp and pen change at 21 dpp (V28PC21; n = 108), (2) vaccination and pen change at 28 dpp (V28PC28; n = 99), and (3) vaccination and pen change at 21 dpp (V21PC21; n = 101). When cows changed pens, an acidogenic diet was introduced. Every other week, a group of 43 to 53 animals were enrolled and electronic data loggers (IceQube, IceRobotics) were fitted to the hind leg of individual cows to assess their LT. Blood samples were collected at 28, 26, 21, 19, 14 dpp and at calving. Parity, body condition score, days dry, and gestation length were not different among groups. Overall, V28PC28 cows had 7 additional days in prepartum pens consuming an acidogenic diet compared with V28PC21 or V21PC21 cows. Regardless of treatment group, cows in the far-off pen had 43 min/d less LT (709 vs. 753 min/d) and increased day-to-day coefficient of variation of LT (0.21 vs. 0.10) compared with cows within the prepartum pen. On average, for the 7 d following vaccination alone (28 to 22 dpp period), V28PC21 cows had ~22 min/d less LT compared with V21PC21 cows. Serum concentrations of glucose, nonesterified fatty acids, and IGF-1 were altered following vaccination alone, pen change alone, or vaccination plus pen change with an acidogenic diet before calving. At calving, V28PC21 cows had greater glucose concentrations (6.45 mmol/L) compared with V21PC21 cows (5.76 mmol/L), with V28PC28 cows intermediate (6.11 mmol/L). The assessment of Ca status at calving revealed that V28PC21 cows had greater Ca concentration (2.34 mmol/L) with lower subclinical hypocalcemia (<2.0 mmol/L; 17.3%) compared with V21PC21 cows (2.17 mmol/L and 31.9%), with V28PC28 cows intermediate (2.28 mmol/L and 25.2%). Serum concentrations of IGF-1 at calving were also greater for V28PC21 (3.43 nmol/L) cows compared with V21PC21 (2.69 nmol/L), with V28PC28 cows intermediate (3.07 nmol/L). Overall, V28PC21 cows had greater serum glucose, IGF-1, and ~46% reduction in subclinical hypocalcemia (from 31.9 to 17.3%) compared with V21PC21 cows but did not differ from V28PC28 cows (25.2%). These findings provided evidence that vaccinating cows at 28 dpp, followed 7 d later by pen change with an acidogenic diet at 21 dpp, would be beneficial.

Effects of prepartum vaccination timing relative to pen change with an acidogenic diet on serum and colostrum immunoglobulins in Holstein dairy cows.

The objective of the present study was to assess the effects of prepartum vaccination timing relative to pen change with an acidogenic diet at 28 or 21 d before expected parturition (dpp) on colostral and serum IgG concentrations at calving in pregnant Holstein dairy cows. Pregnant multiparous Holstein cows (n = 308) from one large dairy herd were randomly allocated into 1 of 3 treatment groups at 35 ± 3 dpp: (1) vaccination at 28 dpp and pen change at 21 dpp (V28PC21; n = 108), (2) vaccination and pen change at 28 dpp (V28PC28; n = 99), and (3) vaccination and pen change at 21 dpp (V21PC21; n = 101). An acidogenic diet was fed when cows changed pens at 28 or 21 dpp. Blood and colostral samples were collected within 1 h following parturition. The total number of clinical mastitis (CM) cases within the first 150 d in milk (DIM) were recorded. The V28PC21 cows had greater colostral IgG concentrations at calving (160.4 ± 7.0 g/L) compared with V21PC21 cows (134.4 ± 7.0 g/L), and V28PC28 cows were intermediate (148.3 ± 7.2 g/L). At calving, V28PC21 cows had lower serum IgG concentrations (29.1 ± 1.2 g/L) compared with V21PC21 cows (32.2 ± 1.2 g/L) or V28PC28 cows (32.6 ± 1.3 g/L). Overall, 41% of V21PC21 cows received the booster vaccinations with at least 21 d before actual calving compared with V28PC21 or V28PC28 cows (88 and 86% respectively). The shorter the interval from prepartum booster vaccination to calving, the lower the colostral IgG at calving, regardless of treatment groups. Vaccinating at 28 dpp and pen change with an acidogenic diet at 21 dpp tended to reduce the rate of CM within the first 150 DIM compared with V21PC21. These findings provide evidence that vaccinating cows at 28 dpp, followed by pen change with an acidogenic diet at 21 dpp, improved the concentrations of colostral IgG at calving and tended to reduce the rate of CM. The interaction of prepartum vaccination timing relative to feeding an acidogenic diet should be considered when implementing an effective vaccination program to enhance overall herd health.