# Vaccination and Medication Procedures for Cattle

BC-1001 – Revised: June, 2006
Dr. Larry W. Olson - Extension Animal Scientist

This table is useful for calculating a calf's age, a cow's calving interval, a cow's expected calving date and a cow's breeding date. The following are examples of how to use the table:

Calf Age

Weaning Date = July 1, 1996 = Day 547 + 1 for leap year = Day 548

Birth Date = November 15, 1995 = Day 319

Calf's Weaning Age = 548 - 319 = 229 days-old

Cow's Calving Interval

1996 Calving Date = March 5, 1996 = Day 429 + 1 for leap year = Day 430

1995 Calving Date = January 25, 1995 = Day 25

Cow's Calving Interval = 430 - 25 = 405 days

Cow's Expected Calving Date

1995 Breeding Date = February 10, 1995 = Day 41

Average Gestation Length for Cow's Breed = 283 days

Cow's Expected Calving Date = 41+ 283 = Day 324 = November 20, 1995

Cow's Breeding Date

1996 Calving Date = March 5, 1996 = Day 429 + 1 for leap year = Day 430

Average Gestation Length for Cow's Breed = 283 days

Cow's Breeding Date = 430 - 283 = Day 147 = May 27, 1995

# Age, Calving Interval & Gestation Table

 Year 1 Day Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 1 1 32 60 91 121 152 182 213 244 274 305 335 2 2 33 61 92 122 153 183 214 245 275 306 336 3 3 34 62 93 123 154 184 215 246 276 307 337 4 4 35 63 94 124 155 185 216 247 277 308 338 5 5 36 64 95 125 156 186 217 248 278 309 339 6 6 37 65 96 126 157 187 218 249 279 310 340 7 7 38 66 97 127 158 188 219 250 280 311 341 8 8 39 67 98 128 159 189 220 251 281 312 342 9 9 40 68 99 129 160 190 221 252 282 313 343 10 10 41 69 100 130 161 191 222 253 283 314 344 11 11 42 70 101 131 162 192 223 254 284 315 345 12 12 43 71 102 132 163 193 224 255 285 316 346 13 13 44 72 103 133 164 194 225 256 286 317 347 14 14 45 73 104 134 165 195 226 257 287 318 348 15 15 46 74 105 135 166 196 227 258 288 319 349 16 16 47 75 106 136 167 197 228 259 289 320 350 17 17 48 76 107 137 168 198 229 260 290 321 351 18 18 49 77 108 138 169 199 230 261 291 322 352 19 19 50 78 109 139 170 200 231 262 292 323 353 20 20 51 79 110 140 171 201 232 263 293 324 354 21 21 52 80 111 141 172 202 233 264 294 325 355 22 22 53 81 112 142 173 203 234 265 295 326 356 23 23 54 82 113 143 174 204 235 266 296 327 357 24 24 55 83 114 144 175 205 236 267 297 328 358 25 25 56 84 115 145 176 206 237 268 298 329 359 26 26 57 85 116 146 177 207 238 269 299 330 360 27 27 58 86 117 147 178 208 239 270 300 331 361 28 28 59 87 118 148 179 209 240 271 301 332 362 29 29 88 119 149 180 210 241 272 302 333 363 30 30 89 120 150 181 211 242 273 303 334 364 31 31 90 151 212 243 304 365 Year 2 Day Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 1 366 397 425 456 486 517 547 578 609 639 670 700 2 367 398 426 457 487 518 548 579 610 640 671 701 3 368 399 427 458 488 519 549 580 611 641 672 702 4 369 400 428 459 489 520 550 581 612 642 673 703 5 370 401 429 460 490 521 551 582 613 643 674 704 6 371 402 430 461 491 522 552 583 614 644 675 705 7 372 403 431 462 492 523 553 584 615 645 676 706 8 373 404 432 463 493 524 554 585 616 646 677 707 9 374 405 433 464 494 525 555 586 617 647 678 708 10 375 406 434 465 495 526 556 587 618 648 679 709 11 376 407 435 466 496 527 557 588 619 649 680 710 12 377 408 436 467 497 528 558 589 620 650 681 711 13 378 409 437 468 498 529 559 590 621 651 682 712 14 379 410 438 469 499 530 560 591 622 652 683 713 15 380 411 439 470 500 531 561 592 623 653 684 714 16 381 412 440 471 501 532 562 593 624 654 685 715 17 382 413 441 472 502 533 563 594 625 655 686 716 18 383 414 442 473 503 534 564 595 626 656 687 717 19 384 415 443 474 504 535 565 596 627 657 688 718 20 385 416 444 475 505 536 566 597 628 658 689 719 21 386 417 445 476 506 537 567 598 629 659 690 720 22 387 418 446 477 507 538 568 599 630 660 691 721 23 388 419 447 478 508 539 569 600 631 661 692 722 24 389 420 448 479 509 540 570 601 632 662 693 723 25 390 421 449 480 510 541 571 602 633 663 694 724 26 391 422 450 481 511 542 572 603 634 664 695 725 27 392 423 451 482 512 543 573 604 635 665 696 726 28 393 424 452 483 513 544 574 605 636 666 697 727 29 394 453 484 514 545 575 606 637 667 698 728 30 395 454 485 515 546 576 607 638 668 699 729 31 396 455 516 577 608 669 730

For leap year, add 1 day to all dates after February 29. Example, March 1, 1996 is day 61 rather than day 60.