Table 1.
Chemical composition (g/kg DM), IVOMD (g/kg), and ME (MJ/kg DM) of shrub species (n = 11) browsed by goats in Southern Mediterranean forest rangeland of northern Morocco during two contrasting years.
| Item | 2016 (Dry Year) | 2017 (Wet Year) | SEM | p-Value (2016–2017) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Spring | Summer | Autumn | SEM | p-Value | Spring | Summer | Autumn | SEM | p-Value | S | Y | Y × S | ||
| Arbutus unedo | ||||||||||||||
| DM | 576 b | 660 a | 445 c | 31.6 | <0.001 | 550 b | 647 a | 427 c | 32.3 | <0.001 | 22 | <0.001 | 0.035 | 0.828 |
| OM | 962 | 964 | 955 | 4.7 | 0.768 | 974 | 974 | 968 | 3.72 | 0.775 | 3.23 | 0.6 | 0.116 | 0.99 |
| CP | 69.8 a | 52.7 b | 60.3 ab | 2.79 | 0.009 | 60 | 67.3 | 70.7 | 2.24 | 0.13 | 1.84 | 0.156 | 0.054 | 0.003 |
| CT | 91.4 b | 112 ab | 121 a | 5.1 | 0.014 | 83.7 b | 101 ab | 110 a | 4.56 | 0.018 | 3.53 | <0.001 | 0.028 | 0.926 |
| EE | 70.3 b | 91.3 a | 67.7 b | 4.11 | 0.005 | 73.3 b | 96.6 a | 72.3 b | 4.27 | 0.003 | 2.93 | <0.001 | 0.138 | 0.936 |
| NDF | 354 b | 485 a | 482 a | 23.5 | 0.004 | 344 b | 491 a | 488 a | 26.1 | 0.003 | 17 | <0.001 | 0.972 | 0.884 |
| ADF | 257 c | 324 b | 363 a | 16 | <0.001 | 243 c | 346 b | 377 a | 20.4 | <0.001 | 12.6 | <0.001 | 0.203 | 0.056 |
| ADL | 110 b | 172 a | 185 a | 12.7 | 0.004 | 105 b | 191 a | 197 a | 15.7 | 0.001 | 9.82 | <0.001 | 0.324 | 0.538 |
| IVOMD | 603 a | 506 b | 387 c | 31.5 | <0.001 | 617 a | 512 b | 405 c | 30.8 | <0.001 | 21.4 | <0.001 | 0.037 | 0.637 |
| ME | 9.11 a | 7.34 b | 5.13 c | 0.582 | <0.001 | 9.23 a | 7.56 b | 5.20 c | 0.591 | <0.001 | 0.403 | <0.001 | 0.372 | 0.899 |
| Calicotome villosa | ||||||||||||||
| DM | 228 c | 487 a | 366 b | 37.6 | <0.001 | 215 c | 471 a | 326 b | 37.1 | <0.001 | 25.7 | <0.001 | 0.002 | 0.138 |
| OM | 927 b | 984 a | 950 ab | 10.1 | 0.038 | 937 b | 988 a | 961 ab | 9.33 | 0.044 | 6.75 | 0.002 | 0.383 | 0.95 |
| CP | 175 | 190 | 232 | 10.9 | 0.059 | 161 b | 201 ab | 238 a | 12.9 | 0.016 | 8.18 | 0.001 | 0.944 | 0.603 |
| CT | 3.81 | 2.43 | 2.97 | 0.439 | 0.492 | 2.87 | 1.97 | 2.09 | 0.202 | 0.133 | 0.252 | 0.178 | 0.137 | 0.905 |
| EE | 31.3 a | 27.0 a | 22.0 b | 1.44 | 0.002 | 34.3 a | 30.3 b | 30.7 ab | 0.777 | 0.033 | 0.999 | <0.001 | <0.001 | 0.019 |
| NDF | 520 b | 619 a | 593 a | 15.3 | <0.001 | 511 b | 629 a | 601 a | 18.1 | <0.001 | 11.5 | <0.001 | 0.632 | 0.425 |
| ADF | 417 b | 464 a | 417 b | 8.63 | 0.007 | 406 b | 482 a | 429 b | 12 | 0.002 | 7.22 | <0.001 | 0.366 | 0.212 |
| ADL | 95.7 b | 124 a | 117 a | 4.65 | 0.004 | 94.7 c | 138 a | 128 b | 7.08 | <0.001 | 4.19 | <0.001 | 0.017 | 0.028 |
| IVOMD | 545 a | 439 b | 351 c | 28.4 | <0.001 | 554 a | 443 b | 362 c | 28.1 | <0.001 | 19.4 | <0.001 | 0.239 | 0.906 |
| ME | 7.74 a | 6.17 b | 4.42 c | 0.485 | <0.001 | 7.89 a | 6.16 b | 4.49 c | 0.499 | <0.001 | 0.338 | <0.001 | 0.6077 | 0.889 |
| Cistus crispus | ||||||||||||||
| DM | 414 b | 528 a | 344 c | 27 | <0.001 | 399 b | 514 a | 332 c | 26.9 | <0.001 | 18.6 | <0.001 | 0.064 | 0.983 |
| OM | 945 a | 946 a | 914 b | 6.56 | 0.049 | 963 a | 951 ab | 927 b | 6.56 | 0.034 | 4.73 | 0.002 | 0.083 | 0.695 |
| CP | 113 a | 60.3 b | 76.0 b | 8.71 | 0.009 | 99.7 | 79.3 | 85.3 | 5.05 | 0.266 | 4.92 | 0.002 | 0.451 | 0.166 |
| CT | 15.1 b | 65.0 a | 61.7 a | 8.2 | <0.001 | 13.7 b | 61.3 a | 54.0 a | 7.51 | <0.001 | 5.42 | <0.001 | 0.083 | 0.537 |
| EE | 15.8 b | 21.8 a | 17.9 ab | 0.986 | 0.011 | 19 | 23.3 | 20.3 | 0.873 | 0.098 | 0.7 | 0.001 | 0.018 | 0.758 |
| NDF | 309 b | 242 c | 384 a | 20.8 | <0.001 | 305 b | 256 c | 393 a | 20.3 | <0.001 | 14.1 | <0.001 | 0.318 | 0.43 |
| ADF | 266 a | 207 b | 252 a | 10.4 | 0.02 | 251 | 226 | 265 | 7.46 | 0.076 | 6.25 | 0.002 | 0.529 | 0.257 |
| ADL | 103 b | 184 a | 170 a | 12.9 | <0.001 | 93.0 b | 195 a | 184 a | 16.4 | <0.001 | 10.1 | <0.001 | 0.261 | 0.101 |
| IVOMD | 642 a | 408 c | 488 b | 34.3 | <0.001 | 652 a | 412 c | 498 b | 35.2 | <0.001 | 23.9 | <0.001 | 0.039 | 0.676 |
| ME | 9.63 a | 5.59 c | 7.12 b | 0.589 | <0.001 | 9.76 a | 5.71 c | 7.20 b | 0.592 | <0.001 | 0.405 | <0.001 | 0.059 | 0.891 |
| Cistus monspeliensis | ||||||||||||||
| DM | 585 b | 698 a | 379 c | 46.8 | <0.001 | 573 b | 676 a | 366 c | 45.8 | <0.001 | 31.8 | <0.001 | 0.011 | 0.717 |
| OM | 905 c | 952 a | 930 b | 6.94 | <0.001 | 918 c | 966 a | 947 b | 7.32 | <0.001 | 5.21 | <0.001 | <0.001 | 0.832 |
| CP | 98.4 a | 84.7 ab | 66.3 b | 5.36 | 0.015 | 88.0 ab | 98.7 a | 73.7 b | 4.39 | 0.032 | 3.39 | 0.001 | 0.405 | 0.088 |
| CT | 46.0 c | 65.6 b | 78.0 a | 4.82 | <0.001 | 40.7 b | 54.7 a | 65.7 a | 3.93 | 0.004 | 3.23 | <0.001 | 0.001 | 0.439 |
| EE | 56.4 b | 90.6 a | 96.0 a | 6.39 | <0.001 | 60.6 b | 98.6 a | 101 a | 6.78 | <0.001 | 4.57 | <0.001 | 0.061 | 0.845 |
| NDF | 388 c | 492 a | 434 b | 15.2 | <0.001 | 377 c | 503 a | 440 b | 18.3 | <0.001 | 11.6 | <0.001 | 0.588 | 0.062 |
| ADF | 220 c | 255 b | 314 a | 13.8 | <0.001 | 206 c | 274 b | 325 a | 17.6 | <0.001 | 10.9 | <0.001 | 0.23 | 0.028 |
| ADL | 172 b | 176 b | 205 a | 5.81 | 0.007 | 162 c | 187 b | 221 a | 8.72 | <0.001 | 5.13 | <0.001 | 0.164 | 0.04 |
| IVOMD | 592 a | 407 c | 489 b | 26.8 | <0.001 | 601 a | 412 c | 501 b | 27.4 | <0.001 | 18.6 | <0.001 | 0.012 | 0.617 |
| ME | 8.27 a | 5.39 c | 6.72 b | 0.417 | <0.001 | 8.46 a | 5.49 c | 6.77 b | 0.431 | <0.001 | 0.291 | <0.001 | 0.053 | 0.562 |
| Cistus salviifolius | ||||||||||||||
| DM | 488 a | 441 b | 366 c | 18 | <.0001 | 477 a | 424 b | 353 c | 18.2 | <0.001 | 12.5 | <0.001 | 0.019 | 0.913 |
| OM | 876 b | 854 b | 906 a | 8 | 0.001 | 890 b | 861 c | 921 a | 9.24 | 0.001 | 6.1 | <0.001 | 0.021 | 0.714 |
| CP | 108 a | 80.7 b | 70.7 b | 5.73 | <0.001 | 95.7 | 94 | 83 | 2.68 | 0.091 | 3.11 | <0.001 | 0.107 | 0.002 |
| CT | 25.0 c | 78.0 a | 49.7 b | 7.96 | <0.001 | 21.0 c | 61.0 a | 41.7 b | 5.91 | <0.001 | 4.95 | <0.001 | 0.006 | 0.215 |
| EE | 23.3 b | 50.3 a | 40.6 a | 4.23 | 0.002 | 27.3 c | 63.6 a | 46.3 b | 5.42 | <0.001 | 3.46 | <0.001 | 0.007 | 0.274 |
| NDF | 417 c | 506 a | 485 b | 13.6 | <0.001 | 406 c | 515 a | 496 b | 16.9 | <0.001 | 10.5 | <0.001 | 0.434 | 0.025 |
| ADF | 252 c | 341 a | 291 b | 13.23 | <0.001 | 239 c | 360 a | 303 b | 17.7 | <0.001 | 10.7 | <0.001 | 0.282 | 0.071 |
| ADL | 154 c | 228 a | 206 b | 11.1 | <0.001 | 142 b | 238 a | 224 a | 15.2 | <0.001 | 9.14 | <0.001 | 0.08 | 0.003 |
| IVOMD | 602 a | 439 b | 440 b | 27.5 | <0.001 | 611 a | 445 b | 455 b | 27.2 | <0.001 | 18.8 | <0.001 | 0.181 | 0.877 |
| ME | 8.47 a | 5.91 c | 6.32 b | 0.398 | <0.001 | 8.60 a | 5.91 c | 6.38 b | 0.416 | <0.001 | 0.279 | <0.001 | 0.302 | 0.725 |
| Erica arborea | ||||||||||||||
| DM | 571 b | 650 a | 500 c | 21.8 | <0.001 | 551 b | 634 a | 475 c | 23.1 | <0.001 | 15.6 | <0.001 | 0.001 | 0.711 |
| OM | 947 | 955 | 965 | 4.69 | 0.331 | 960 | 967 | 977 | 4.15 | 0.24 | 3.41 | 0.083 | 0.051 | 0.999 |
| CP | 88.7 a | 53.7 c | 69.7 b | 5.38 | 0.002 | 73.7 | 65 | 77.3 | 2.66 | 0.146 | 2.92 | <0.001 | 0.673 | 0.009 |
| CT | 108 | 107 | 119 | 2.78 | 0.143 | 100 | 91.7 | 108 | 3.21 | 0.111 | 2.48 | 0.019 | 0.006 | 0.674 |
| EE | 96.3 a | 90.0 a | 46.6 b | 7.89 | <0.001 | 99.6 a | 93.6 a | 57.0 b | 6.77 | <0.001 | 5.09 | <0.001 | 0.012 | 0.294 |
| NDF | 439 c | 531 b | 578 a | 21 | <0.001 | 428 c | 544 b | 586 a | 24 | <0.001 | 15.4 | <0.001 | 0.611 | 0.323 |
| ADF | 341 c | 399 b | 445 a | 15.6 | <0.001 | 328 c | 414 b | 458 a | 19.5 | <0.001 | 12.1 | <0.001 | 0.448 | 0.178 |
| ADL | 217 b | 307 a | 311 a | 15.4 | <0.001 | 207 b | 320 a | 324 a | 19.3 | <0.001 | 12 | <0.001 | 0.042 | 0.002 |
| IVOMD | 479 a | 343 c | 407 b | 19.9 | <0.001 | 486 a | 348 c | 417 b | 20.3 | <0.001 | 13.8 | <0.001 | 0.257 | 0.948 |
| ME | 6.62 a | 4.58 c | 5.79 b | 0.299 | <0.001 | 6.77 a | 4.41 c | 5.86 b | 0.347 | <0.001 | 0.222 | <0.001 | 0.891 | 0.282 |
| Lavandula stoechas | ||||||||||||||
| DM | 299 c | 475 a | 409 b | 25.7 | <0.001 | 281 c | 459 a | 385 b | 25.8 | <0.001 | 17.8 | <0.001 | <0.001 | 0.491 |
| OM | 944 | 939 | 916 | 6.24 | 0.133 | 953 | 954 | 930 | 6.25 | 0.217 | 4.56 | 0.031 | 0.116 | 0.936 |
| CP | 106 a | 83.0 b | 72.7 b | 5.09 | <0.001 | 224 a | 96.7 b | 80.0 b | 2.81 | 0.014 | 2.83 | <0.001 | 0.374 | <0.001 |
| CT | 3.07 | 3.57 | 2.57 | 0.222 | 0.191 | 2.57 | 2.93 | 2.2 | 0.237 | 0.513 | 0.169 | 0.118 | 0.136 | 0.941 |
| EE | 90.0 a | 34.3 b | 33.0 b | 9.41 | <0.001 | 96.6 a | 38.6 b | 42.3 b | 9.38 | <0.001 | 6.5 | <0.001 | <0.001 | 0.112 |
| NDF | 418 c | 472 a | 446 b | 8.24 | 0.001 | 409 c | 486 a | 455 b | 11.5 | <0.001 | 6.87 | <0.001 | 0.341 | 0.11 |
| ADF | 253 b | 313 a | 298 a | 9.42 | <0.001 | 238 b | 326 a | 313 a | 13.9 | <0.001 | 8.16 | <0.001 | 0.312 | 0.03 |
| ADL | 173 b | 208 a | 211 a | 6.23 | <0.001 | 160 b | 215 a | 224 a | 10.1 | <0.001 | 5.76 | <0.001 | 0.264 | 0.002 |
| IVOMD | 698 a | 476 c | 512 b | 34.5 | <0.001 | 704 a | 484 c | 522 b | 34 | <0.001 | 23.5 | <0.001 | 0.108 | 0.936 |
| ME | 10.2 a | 6.69 c | 7.29 b | 0.54 | <0.001 | 10.3 a | 6.90 c | 7.40 b | 0.539 | <0.001 | 0.371 | <0.001 | 0.025 | 0.829 |
| Myrtus communis | ||||||||||||||
| DM | 554 a | 531 b | 437 c | 18.1 | <0.001 | 533 a | 515 a | 420 b | 17.7 | <0.001 | 12.4 | <0.001 | <0.001 | 0.851 |
| OM | 952 | 939 | 948 | 3.79 | 0.428 | 962 | 953 | 959 | 3.31 | 0.571 | 2.81 | 0.245 | 0.045 | 0.959 |
| CP | 89.7 a | 72.3 b | 82.7 ab | 3.03 | 0.03 | 75.7 b | 84.7 ab | 90.7 a | 2.57 | 0.022 | 1.94 | 0.061 | 0.415 | 0.002 |
| CT | 96.0 b | 128 a | 115 a | 4.88 | 0.002 | 88.0 b | 116 a | 110 a | 4.47 | 0.002 | 3.37 | <0.001 | 0.008 | 0.562 |
| EE | 42.6 a | 41.0 a | 24.0 b | 3.09 | <0.001 | 46.3 a | 48.0 a | 27.6 b | 3.37 | <0.001 | 2.29 | <0.001 | 0.005 | 0.543 |
| NDF | 379 a | 362 ab | 336 b | 7.37 | 0.027 | 369 | 372 | 346 | 6.05 | 0.17 | 4.64 | 0.006 | 0.642 | 0.462 |
| ADF | 218 | 228 | 242 | 4.65 | 0.067 | 205 b | 242 a | 252 a | 7.76 | 0.003 | 4.41 | <0.001 | 0.475 | 0.087 |
| ADL | 102 | 93 | 94.3 | 2.01 | 0.169 | 93.7 b | 108 a | 106 a | 2.55 | 0.015 | 1.74 | 0.571 | 0.019 | 0.003 |
| IVOMD | 493 b | 550 a | 485 b | 10.6 | <0.001 | 500 b | 556 a | 504 b | 9.21 | <0.001 | 6.94 | <0.001 | 0.024 | 0.374 |
| ME | 7.24 b | 8.24 a | 7.16 b | 0.178 | <0.001 | 7.41 b | 8.02 a | 7.28 b | 0.12 | <0.001 | 0.104 | <0.001 | 0.673 | 0.047 |
| Phillyrea media | ||||||||||||||
| DM | 523 c | 612 a | 570 b | 13.1 | <0.001 | 507 c | 598 a | 555 b | 13.5 | <0.001 | 9.31 | <0.001 | 0.004 | 0.974 |
| OM | 960 | 970 | 962 | 2.74 | 0.338 | 974 | 978 | 975 | 2.52 | 0.78 | 2.3 | 0.3 | 0.01 | 0.843 |
| CP | 109 a | 86.3 b | 81.0 b | 4.4 | <0.001 | 96 | 97.3 | 92 | 1.48 | 0.351 | 2.28 | <0.001 | 0.124 | <0.001 |
| CT | 2.73 | 2.67 | 3.17 | 0.28 | 0.784 | 2.4 | 2.2 | 2.77 | 0.241 | 0.685 | 0.186 | 0.553 | 0.344 | 0.991 |
| EE | 23.6 | 25.6 | 28 | 1.22 | 0.401 | 28.6 | 28.6 | 31.6 | 1.47 | 0.692 | 1.04 | 0.337 | 0.076 | 0.918 |
| NDF | 399 b | 435 a | 424 ab | 6.79 | 0.047 | 387 b | 448 a | 429 a | 9.98 | 0.007 | 5.86 | 0.003 | 0.765 | 0.379 |
| ADF | 272 a | 259 ab | 250 b | 4.07 | 0.043 | 258 b | 272 a | 255 b | 2.92 | 0.005 | 2.44 | 0.006 | 0.651 | 0.011 |
| ADL | 171 a | 124 b | 119 b | 8.42 | <0.001 | 159 a | 136 b | 134 b | 4.56 | 0.008 | 4.69 | <0.001 | 0.126 | 0.007 |
| IVOMD | 515 a | 429 b | 413 b | 16.9 | 0.002 | 523 a | 435 b | 425 b | 16.7 | 0.003 | 11.6 | <0.001 | 0.396 | 0.967 |
| ME | 7.29 a | 5.96 b | 5.82 b | 0.247 | 0.001 | 7.46 a | 5.76 b | 5.90 b | 0.285 | <0.001 | 0.183 | <0.001 | 0.889 | 0.504 |
| Pistacia lentiscus | ||||||||||||||
| DM | 547 c | 622 a | 590 b | 11.1 | <0.001 | 530 c | 607 a | 578 b | 11.5 | <0.001 | 7.98 | <0.001 | 0.006 | 0.882 |
| OM | 959 a | 927 b | 954 a | 5.25 | 0.001 | 973 a | 941 b | 964 a | 5.21 | 0.005 | 3.91 | <0.001 | 0.001 | 0.79 |
| CP | 93.0 b | 91.7 b | 106 a | 2.41 | 0.003 | 78.0 b | 105 a | 113 a | 5.45 | <0.001 | 2.9 | <0.001 | 0.32 | <0.001 |
| CT | 175 | 191 | 185 | 3.64 | 0.187 | 161 b | 177 a | 172 ab | 2.85 | 0.033 | 2.79 | 0.012 | 0.003 | 0.997 |
| EE | 27.3 a | 23.6 b | 23.3 b | 0.741 | 0.016 | 34 | 30 | 27.3 | 1.52 | 0.214 | 1.07 | 0.027 | 0.002 | 0.716 |
| NDF | 448 b | 483 a | 422 c | 8.98 | <0.001 | 437 b | 493 a | 426 b | 10.4 | <0.001 | 6.68 | <0.001 | 0.591 | 0.012 |
| ADF | 284 a | 248 b | 270 ab | 5.95 | 0.014 | 268 | 263 | 284 | 4.33 | 0.109 | 3.61 | 0.006 | 0.363 | 0.037 |
| ADL | 118 b | 165 a | 168 a | 8.5 | 0.002 | 109 b | 178 a | 186 a | 12.57 | <0.001 | 7.42 | <0.001 | 0.132 | 0.069 |
| IVOMD | 505 a | 443 c | 471 b | 9.28 | <0.001 | 508 a | 453 c | 483 b | 8.18 | <0.001 | 6.09 | <0.001 | 0.022 | 0.453 |
| ME | 7.21 | 6.6 | 6.74 | 0.121 | 0.069 | 7.37 a | 6.42 b | 6.83 ab | 0.159 | 0.018 | 0.097 | 0.001 | 0.876 | 0.567 |
| Rubus ulmifolius | ||||||||||||||
| DM | 371 b | 409 a | 410 a | 6.69 | <0.001 | 356 b | 394 a | 406 a | 8.43 | 0.008 | 5.42 | <0.001 | 0.033 | 0.601 |
| OM | 908 b | 924 ab | 939 a | 5.26 | 0.025 | 922 b | 936 ab | 947 a | 4.33 | 0.028 | 3.59 | 0.001 | 0.02 | 0.862 |
| CP | 125 | 119 | 139 | 4 | 0.101 | 110 b | 132 ab | 152 a | 6.61 | 0.004 | 3.77 | 0.001 | 0.404 | 0.036 |
| CT | 136 | 138 | 119 | 3.77 | 0.052 | 116 | 121 | 109 | 2.31 | 0.122 | 2.87 | 0.007 | <0.001 | 0.419 |
| EE | 18.6 | 18 | 21.3 | 0.927 | 0.341 | 24 | 21.6 | 27 | 1.35 | 0.306 | 0.991 | 0.112 | 0.009 | 0.856 |
| NDF | 365 | 369 | 361 | 4.78 | 0.834 | 352 | 380 | 372 | 6.48 | 0.211 | 3.92 | 0.303 | 0.73 | 0.381 |
| ADF | 199 | 208 | 201 | 3.07 | 0.485 | 186 b | 221 a | 207 a | 5.59 | 0.005 | 3.11 | 0.003 | 0.548 | 0.065 |
| ADL | 75.3 | 70.3 | 62.3 | 2.75 | 0.145 | 67.3 b | 83.0 a | 76.7 ab | 2.8 | 0.039 | 2.05 | 0.166 | 0.055 | 0.017 |
| IVOMD | 405 b | 443 a | 444 a | 7.19 | 0.008 | 413 b | 452 a | 457 a | 7.75 | 0.012 | 5.27 | <0.001 | 0.095 | 0.936 |
| ME | 5.55 b | 6.62 a | 6.24 ab | 0.177 | 0.001 | 5.71 b | 6.46 a | 6.43 a | 0.147 | 0.027 | 0.112 | 0.001 | 0.637 | 0.511 |
DM, dry matter, OM, organic matter; CP, crude protein; CT, condensed tannins; EE, ether extract; NDF, neutral detergent fiber; ADF, acid detergent fiber; ADL, lignin; IVOMD, in vitro organic matter digestibility; ME, metabolizable energy; S, season; Y, year; SEM, standard error of the means. Within a row, values with different letters are significantly different (p < 0.05).