View Full Table | Close Full ViewTable 1.

Ingredients and chemical composition of the experimental diet

 
Item Value
Dietary ingredient, % DM
    Dehydrated corn plant1 45.4
    Cracked corn grain 26.6
    Soybean meal 22.3
    Soybean oil 1.6
    Limestone 1.0
    Mineral supplement2 2.2
    Ammonium chloride 0.9
Diet chemical composition,3 g/kg of DM ± SD
    DM 854 ± 10.9
    OM 935 ± 2.0
    CP 204 ± 5.4
    Crude fat 80 ± 4.9
    NDF 355 ± 25.0
    iNDF4 108 ± 10.5
    Lignin 57 ± 3.4
1Dehydrated corn plant consisted of whole corn plants harvested and chopped when the kernel milk line was approximately two-thirds of the distance down the kernel.
2Composition, per kilogram, as-fed basis: 190 g of Ca, 92 g of Cl, 73 g of P, 62 g of Na, 44 g of Mg, 1.35 g of Zn, 1.06 g of Fe, 0.94 mg of Mn, 0.73 g of F, 0.34 g of Cu, 18 mg of Se, 16 mg of I, and 3 mg of Co.
3Mean and SD of 10 composite samples. Chemical composition of the diet was calculated from the individual ingredients.
4iNDF = indigestible NDF.



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Body weight, feed intake before slaughter, pH of digesta in the reticulorumen and cecum, and wet weight of the gastrointestinal tissue (without digesta) in goats of different sexes and slaughtered at 3 different target weights (initial, intermediate, and final)

 
Initial
Intermediate
Final
P-value1
Item Females Castrated males Intact males Females Castrated males Intact males Females Castrated Males Intact males SEM Sex SWL SWQ Sex × SW
No. 6 7 7 6 7 7 6 6 6
BW, kg 17.0 16.4 16.6 22.2b 22.9b 24.2a 30.0b 31.2b 32.6a 0.43 <0.01 <0.01 <0.01 0.01
Intake,2 % BW
    DM 3.5 4.0 3.9 3.8 3.6 3.5 3.0 3.3 3.1 0.19 0.39 <0.01 0.25 0.44
    OM 3.3 3.7 3.6 3.5 3.3 3.3 2.7 3.1 2.9 0.18 0.39 <0.01 0.25 0.39
    NDF 1.3 1.2 1.2 1.3 1.3 1.2 1.0 1.1 1.1 0.08 0.91 0.03 0.13 0.78
    iNDF3 0.29 0.34 0.36 0.40 0.32 0.30 0.32 0.34 0.36 0.032 0.98 0.77 0.92 0.12
pH
    Reticulorumen 5.6 5.7 5.6 5.8 5.9 5.7 5.7 5.7 5.6 0.06 0.07 0.22 0.01 0.52
    Cecum 6.4 6.3 6.2 6.2 6.6 6.6 6.4 6.5 6.4 0.10 0.41 0.07 0.26 0.19
Wet weight tissues, % BW
    Reticulorumen 2.3 2.4 2.4 2.4 2.2 2.2 2.0 2.1 1.9 0.09 0.27 <0.01 0.12 0.13
    Omasum 0.24 0.24 0.25 0.22 0.29 0.26 0.26 0.27 0.29 0.016 0.11 0.06 0.93 0.15
    Abomasum 0.57 0.58 0.56 0.48 0.51 0.50 0.37 0.45 0.41 0.022 0.08 <0.01 0.61 0.59
    Small intestine 3.1 3.5 3.1 3.0 3.3 2.7 2.4 2.6 2.3 0.15 <0.01 <0.01 0.06 0.66
    Cecum 0.16 0.15 0.16 0.16 0.13 0.14 0.12 0.11 0.12 0.009 0.10 <0.01 0.23 0.87
    Colon4 1.4 1.3 1.3 1.3 1.4 1.3 1.2a 1.2a 1.0a 0.052 0.01 <0.01 0.03 0.02
    Total GIT5 7.7 8.2 7.8 7.6 7.8 7.1 6.3 6.6 5.6 0.235 <0.01 <0.01 0.01 0.49
a,bMeans in the same row with different superscripts are different according to Tukey’s test within of slaughter weight (P ≤ 0.05).
1Main effects and interaction of sex × slaughter weight. SWL = linear effect of slaughter weight; SWQ = quadratic effect of slaughter weight; Sex × SW = interaction of sex × slaughter weight.
2Intake = ingested diet (offered diet – orts).
3iNDF = indigestible NDF.
4Colon represents the colon and rectum.
5Total GIT is the sum of wet weight of reticulorumen, omasum, abomasum, small intestine, cecum, and colon tissues.



View Full Table | Close Full ViewTable 3.

Pool size of different gastrointestinal tract (GIT) segments in goats of different sexes and slaughtered at 3 different target weights (initial, intermediate, and final)

 
Initial
Intermediate
Final
P-value1
Item Females Castrated males Intact males Females Castrated males Intact males Females Castrated males Intact males SEM Sex SWL SWQ Sex × SW
Reticulorumen, g
Wet 2,451 2,444 2,327 3,479 3,394 3,412 3,674 4,231 4,278 223.5 0.66 <0.01 0.23 0.45
DM 334 389 340 475 490 469 488 624 628 33.6 0.05 <0.01 0.64 0.20
NDF 170 179 166 244 226 221 236 311 303 18.8 0.37 <0.01 0.82 0.10
Omasum, g
Wet 45 47 55 60 100 102 121 157 155 13.6 0.03 <0.01 0.34 0.62
DM 11 12 14 14 23 26 28 39 37 3.4 0.01 <0.01 0.34 0.62
NDF 5 4 6 6 9 10 10 14 15 1.4 0.04 <0.01 0.44 0.57
Abomasum, g
Wet 360 375 334 378 438 387 325 439 329 46.1 0.14 0.83 0.22 0.86
DM 52 57 52 45 57 41 41 58 37 8.4 0.10 0.24 0.74 0.89
NDF 17 16 16 19 21 17 16 20 16 2.3 0.33 0.44 0.19 0.74
Small intestine, g
Wet 317 306 346 346 359 358 492 468 545 38.0 0.42 <0.01 0.03 0.90
DM 30 30 36 34 32 35 41 46 53 4.1 0.18 <0.01 0.05 0.79
NDF 6 8 10 8 6 8 9 9 12 1.1 0.03 <0.01 0.04 0.43
Cecum, g
Wet 136 90 113 131ab 171a 100b 179 141 169 17.4 0.36 <0.01 0.75 0.02
DM 17 13 16 17 21 13 23 19 21 2.4 0.49 0.01 0.44 0.06
NDF 7 6 7 7 9 5 9 8 9 1.0 0.82 0.01 0.47 0.12
Colon,2 g
Wet 294 249 272 334 434 455 533 454 553 35.7 0.22 <0.01 0.54 0.09
DM 57 50 58 59 73 85 118 97 101 9.0 0.55 <0.01 0.23 0.20
NDF 23 21 25 24 31 37 50 41 44 3.6 0.35 <0.01 0.22 0.15
Total GIT,3 g
Wet 3,602 3,511 3,459 4,724 4,897 4,813 5,234 5,890 6,005 288.8 0.51 <0.01 0.35 0.57
DM 501 551 522 627 697 669 711 882 867 47.4 0.05 <0.01 0.81 0.63
NDF 238 228 234 298 304 298 316 412 385 26.6 0.37 <0.01 0.91 0.33
a,bMeans in the same row with different superscripts are different according to Tukey’s test within of slaughter weight (P ≤ 0.05).
1Main effects and interaction of sex × slaughter weight. SWL = linear effect of slaughter weight; SWQ = quadratic effect of slaughter weight; Sex × SW = interaction of sex × slaughter weight.
2Colon represents the colon and rectum.
3Total GIT is the sum of wet weight of reticulorumen, omasum, abomasum, small intestine, cecum, and colon tissues.



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Ratio of indigestible NDF (iNDF) to NDF (NDF) in different gastrointestinal tract segments of goats of different sexes and slaughtered at 3 different target weights (initial, intermediate, and final)

 
Initial
Intermediate
Final
P-value1
Item Females Castrated males Intact males Females Castrated males Intact males Females Castrated males Intact males SEM Sex SWL SWQ Sex × SW
iNDF:NDF
    Intake2 0.23 0.27 0.30 0.33 0.26 0.28 0.29 0.31 0.32 0.025 0.50 0.05 0.73 0.16
    Reticulorumen 0.49 0.46 0.46 0.49 0.54 0.53 0.60 0.50 0.50 0.032 0.53 0.02 0.34 0.33
    Omasum 0.52 0.51 0.49 0.44 0.57 0.52 0.62 0.56 0.50 0.048 0.49 0.17 0.48 0.39
    Abomasum 0.79 0.79 0.86 0.67 0.66 0.64 0.77 0.79 0.60 0.063 0.63 0.09 0.02 0.21
    Small intestine 0.44 0.38 0.38 0.49 0.48 0.49 0.47 0.50 0.43 0.041 0.66 0.06 0.09 0.73
    Cecum 0.60 0.64 0.62 0.64 0.69 0.68 0.84 0.65 0.62 0.056 0.59 0.12 0.91 0.40
    Colon3 0.70a 0.68b 0.58b 0.70b 0.76ab 0.82a 0.83a 0.76ab 0.71b 0.031 0.34 <0.01 0.04 0.01
NDF digestibility
    Forestomach 0.61 0.56 0.49 0.52 0.64 0.58 0.60 0.50 0.50 0.046 0.31 0.64 0.27 0.16
Contribution to total digested NDF, %
    Forestomach 91.7 95.6 88.8 90.6 93.8 88.2 99.2 82.9 87.5 5.47 0.53 0.66 0.98 0.54
a,bMeans in the same row with different superscripts are different according to Tukey’s test within of slaughter weight (P ≤ 0.05).
1Main effects and interaction of sex × slaughter weight. SWL = linear effect of slaughter weight; SWQ = quadratic effect of slaughter weight; Sex × SW = interaction of sex × slaughter weight.
2Intake = ratio of iNDF:NDF ingested (offered diet – orts).
3Colon represents the colon and rectum.



View Full Table | Close Full ViewTable 5.

Mean retention time (MRT) of particulate and solute marker in different gastrointestinal tract (GIT) segments of goats of different sexes and slaughtered at 3 different target weights (initial, intermediate, and final), estimated by indigestible NDF (iNDF) for particulate matter and by Cr-EDTA for solute marker

 
Initial
Intermediate
Final
P-value1
Item Females Castrated males Intact males Females Castrated males Intact males Females Castrated males Intact males SEM Sex SWL SWQ Sex × SW
MRT by iNDF, h
    Reticulorumen 42.0 33.2 31.6 36.3 43.6 38.1 36.6 38.3 32.6 3.99 0.33 0.94 0.21 0.36
    Omasum 1.3 1.1 1.0 0.8b 1.8a 1.6a 1.8 1.9 1.6 0.23 0.26 <0.01 0.85 0.01
    Abomasum 8.3 5.3 5.6 4.0 5.2 3.7 3.0 3.8 2.1 0.74 0.08 <0.01 0.50 0.09
    Small intestine 1.3 1.1 1.4 1.1 1.1 1.2 1.1 1.0 1.1 0.14 0.23 0.17 0.71 0.90
    Cecum 2.2 1.3 1.8 1.4 2.4 1.3 1.5 1.4 1.3 0.33 0.62 0.15 0.61 0.07
    Colon2 8.4a 5.2b 6.4ab 4.6b 8.8a 10.8a 10.1a 7.2ab 6.6b 0.91 0.58 0.09 0.35 <0.01
    GIT3 68.0a 44.9b 47.0b 47.9 59.7 56.5 49.5 53.6 43.8 5.78 0.47 0.37 0.39 0.04
MRT by Cr-EDTA, h
    Reticulorumen 2.3 3.7 3.3 3.9 4.1 4.3 5.9 5.4 4.3 0.62 0.65 <0.01 0.90 0.28
    Omasum 0.04 0.09 0.10 0.07 0.11 0.15 0.17 0.17 0.12 0.024 0.26 <0.01 0.87 0.14
    Abomasum 0.5 0.5 0.6 0.5 0.7 0.4 0.5 0.5 0.4 0.09 0.30 0.36 0.55 0.32
    Small intestine 1.0 1.3 1.0 0.8 1.0 1.1 1.0 1.0 1.1 0.13 0.40 0.67 0.16 0.43
    Cecum 1.1 1.0 1.2 1.1ab 1.4a 0.6b 1.4a 0.8b 0.9b 0.17 0.08 0.27 0.74 0.02
    Colon2 4.2 3.8 3.9 3.1b 4.5a 4.2ab 5.9a 4.2b 4.1b 0.45 0.61 0.06 0.18 0.02
    GIT3 9.1 9.7 10.5 8.7b 11.6a 10.0ab 14.5a 11.3b 10.4b 0.71 0.44 <0.01 0.08 <0.01
a,bMeans in the same row with different superscripts are different according to Tukey’s test within of slaughter weight (P ≤ 0.05).
1Main effects and interaction of sex × slaughter weight. SWL = linear effect of slaughter weight; SWQ = quadratic effect of slaughter weight; Sex × SW = interaction of sex × slaughter weight.
2Colon represents the colon and rectum.
3Total GIT is the sum of wet weight of reticulorumen, omasum, abomasum, small intestine, cecum, and colon tissues.