Nutritional evaluation of poultry by-product meal as a protein source for ruminants: small intestinal amino acid flow and disappearance in steers.
Six Angus steers (260+/-4 kg initial BW) fitted with ruminal, duodenal, and ileal cannulas were used in a 6 x 6 Latin square design to evaluate the effect of feeding poultry by-product meal (PBM) on small intestinal flow and disappearance of amino acids. The diets were provided at 2% of BW on a DM basis, formulated to contain 11.5% CP, and consisted of 49% corn silage, 36% cottonseed hulls, and 15% supplement on a DM basis. Supplements were formulated to contain 37% CP with sources of supplemental N being soybean meal (100% SBM) and 0, 25, 50, 75, and 100% PBM, with urea used to balance for N. Duodenal flow of all amino acids increased linearly (P < .07) as PBM increased in the diet and, except for His, increased (P < .09) for 100% PBM compared with 100% SBM. Similar results were observed for duodenal flow of nonbacterial amino acids, which linearly increased (P < .05) with PBM and were greater (P < .05) for 100% PBM than for 100% SBM. Soybean meal increased (P < .09) the duodenal flow of nonbacterial Lys compared with 0% PBM, and 0% PBM increased (P < .04) flow of Val, Ala, and Pro compared with 100% SBM. Duodenal bacterial essential, nonessential, and total amino acid flows were not affected (P > .80) by PBM; however, they were greater (P < .02) for 100% SBM than for 100% PBM. In addition, nonessential and total bacterial amino acid flows were increased (P < .06) for 100% SBM compared with 0% PBM. Small intestinal disappearance of Lys and Pro increased linearly (P < .09) as PBM increased, and 100% PBM increased (P < .07) disappearance of Arg and Ala compared with 100% SBM. Supplemental N source had no effect (P > .31) on apparent small intestinal disappearance of essential, nonessential, and total amino acids. These data suggest that when PBM, SBM, and urea were used as sources of supplemental N, the daily disappearance of amino acids from the small intestine of steer calves consuming a corn silage- and cottonseed hull-based diet was similar. (+info)
Effect of level of whole cottonseed on intake, digestibility, and performance of growing male goats fed hay-based diets.
Twenty-four purebred Boer (Capra hircus hircus) and 12 male kids of 1/2 Boer breeding (initial BW 21 +/- .5 kg) were used in a randomized complete block design to study the effects of increasing level of whole cottonseed (WCS) on ADG, serum urea N, plasma gossypol, live grades, and intake of DM, CP, NDF, ADF, hemicellulose, cellulose, lignin, ether extract, and free gossypol. A subgroup of 16 purebred goats was used to determine digestibility using a 5-d total fecal collection. Goats were blocked by BW and then assigned at random to one of four diets containing 0, 8, 16, or 24% WCS. All diets contained 71% chopped orchardgrass (Dactylis glomerata L.) hay and 29% concentrate; WCS replaced corn and soybean meal to maintain calculated TDN and CP concentrations at 68 and 15% of DM, respectively. Concentrations of NDF in diet DM were 52.4, 55.9, 59.3, and 62.1% with increasing WCS, and the Ca:P ratio was maintained at 2:0. Goats were given ad libitum access to feed and water. Over the 90-d performance phase, DMI (P < .05), CP intake (P < .02), and ADG (P < .01) decreased linearly with increasing WCS in the diet, whereas ether extract (EE) intake increased in a cubic fashion (P < .01). Gain:feed decreased linearly (P < .02) with increasing level of WCS. Addition of WCS resulted in linear decreases in apparent digestibility coefficients of DM (P < .02) and NDF (P < .05), a linear increase in total plasma gossypol (P < .01), and a quadratic increase in serum urea N (P < .04). Apparent digestibility of CP was not affected by WCS level. At the 16 and 24% WCS levels, EE constituted 4.2 and 4.8% of total DMI, respectively. Adding WCS to diets for growing goats had detrimental effects on animal performance, and, based on the possible negative effects of dietary EE and NDF rather than gossypol, economics should dictate whether to use WCS in feeding programs. (+info)
Gossypol isomers bind specifically to blood plasma proteins and spermatozoa of rainbow trout fed diets containing cottonseed meal.
We investigated the role of gossypol isomers binding to blood plasma, seminal plasma and spermatozoa to elucidate gossypol anti-fertility action in the teleost fish, rainbow trout (Oncorhynchus mykiss). Growth and hematological indicators of males were depressed when fish meal protein in diets was completely replaced with cottonseed meal. The cottonseed meal contained equal proportions of (-) (47.8+/-1.6%) and (+) gossypol isomers. Concentrations of spermatozoa were decreased with increasing proportions of gossypol in diets (from 0.22% to 0.95%); however, sperm motility and fertilizing ability were not affected. In contrast to mammals, steroid hormone concentrations were not suppressed in fish given diets with gradual increase of gossypol level. Gossypol concentrations were 100-fold higher in blood plasma than in seminal plasma, confirming a barrier in gossypol transfer between the general circulation and the testis. Spermatozoa accumulated predominantly (+) enantiomer (65-75%) with decreasing proportions as dietary gossypol concentrations increased. Spermatozoa bound most of the gossypol contained in the semen; however, this did not result in impairment of the sperm motility apparatus. Teleost fish sperm rely on ATP stores that accumulate during maturation as a source of energy during activation. In addition, the duration of sperm movement is short in these fish. As such, we hypothesize that the major action of gossypol on mammalian sperm, which is uncoupling of oxidative phosphorylation, does not impair the energy supply required for flagellar beating in fish spermatozoa. (+info)
Reproductive efficiency and maternal-offspring transfer of gossypol in rainbow trout (Oncorhynchus mykiss) fed diets containing cottonseed meal.
In a preceding study, complete substitution of fish meal protein with cottonseed meal (CM) protein did not affect the survival or growth rate of adult rainbow trout over a 6-mo period. Gossypol, a naturally occurring compound in cottonseeds, has an antifertility effect in terrestrial animals, but information regarding salmonid fish is lacking. Female rainbow trout in this experiment were fed diets with either 0, 25, 50, 75, or 100% (diets 1 to 5) of the fish meal protein replaced with CM protein until first maturation and spawning to study long-term effects on growth and reproduction. Feeding diets containing CM over a total period of 10 mo did not result in differences in growth and mortality compared to the control group (P > 0.05). Increased CM incorporation levels resulted in decreased (P < 0.05) blood hemoglobin (10.6 +/- 1.3, 8.4 +/- 1.8, 7.3 +/- 1.1, 6.9 +/- 0.8, and 5.6 +/- 1.4 g/dL) and hematocrit (49.6 +/- 3.9, 38.5 +/- 9.3, 34.4 +/- 3.7, 34.8 +/- 4.9 and 28.0 +/- 6.8%) levels in diets 1 to 5, respectively. The CM incorporation level had no effect (P > 0.05) on the number of eggs produced per female but led to a reduction (P < 0.05) in egg weight. Eyed stage survival of embryos was low in all dietary groups and did not show differences (P > 0.05). However, an increasing CM incorporation level led to a linear increase (P < 0.05) in the number of females that produced no viable embryos (23.1, 37.5, 42.9, 60.0, and 71.4%). Gossypol in the diet was absorbed by the female trout and transferred to the eggs (0, 2.2 +/- 0.5, 6.7 +/- 1.6, 10.6 +/- 4.2, and 20.0 +/- 2.6 micrograms/g in diets 1 to 5, respectively). A high concentration of gossypol remained in the juveniles at the swim-up stage (endogenous yolk-absorbed) (0.6 +/- 0.3, 2.4 +/- 0.3, 3.4 +/- 0.0, and 4.7 +/- 1.0 micrograms/g, diets 2 to 5, respectively). The findings suggest that replacement of the dietary fish meal protein with CM protein has no effect on fish growth and mortality but may lead to a reduction in reproductive performance in female rainbow trout. (+info)
Food intake and growth of guinea pigs fed a cholesterol-containing diet.
Food intake and liveweight gain of 11 cholesterol-fed and 10 control guinea pigs were measured for 33 days to determine whether depressed growth previously observed in young guinea pigs fed cholesterol was due to decreased food intake or to reduced food utilization. The guinea pigs were fed a laboratory stock diet containing 5% cottonseed oil; 1% cholesterol was added to the diet for the experimental group. Results showed that food intake was significantly less in the cholesterol-fed group, while requirements for maintenance and for liveweight gain, as adjusted to metabolic body size (Wkg-0.75), were not significantly different. Food energy retention was estimated by comparing dry body weight and moisture, fat and protein content of two groups of four controls and four cholesterol-fed guinea pigs at the beginning and at the end of a 20-day food-intake period. Values derived for maintenance requirement in this comparative body composition study correlated well with those of the 33-day experiment. We conclude that feeding cholesterol to guinea pigs reduced food intake for unknown reasons but does not affect food utilization. (+info)
Impact of EasiFlo cottonseed on feed intake, apparent digestibility, and rate of passage by goats fed a diet containing 45% hay.
EasiFlo cottonseed (ECS), produced by coating whole cottonseed (WCS) with cornstarch to simplify handling and mixing with other ingredients, is marketed commercially. The objective of this trial was to determine its digestibility by small ruminants. Four mature Nubian wether goats, in a 4 x 4 Latin square arrangement of treatments, were fed diets that contained about 45% bermudagrass hay (BGH) plus 0, 15.7, 32.7, or 50.3% ECS, with the ECS replacing corn and soybean meal (2:1 ratio) in the concentrate portion of the diet. Feed intakes and digestibility of components were measured, and passage rate was estimated using ytterbium-marked BGH. Dry matter intake decreased at an increasing rate (P < 0.01) as ECS or fat concentration in the diet increased. Digestibility was linearly depressed (P= 0.003) as ECS replaced corn and soybean meal in the diet, primarily due to depressed (P < 0.05) digestibility of NDF, ADF, and nonfibrous carbohydrates (NFC). In contrast, fat digestibility tended to increase (P = 0.11) linearly and N utilization was increased (P = 0.04) linearly as ECS concentration was increased. Passage kinetics were not altered. Based on regression estimates of TDN for BGH and literature values of TDN for other feed ingredients, the total digestible nutrient content of ECS for mature goats fed a 45% roughage diet was estimated to be 78.0 +/- 9.1%, a value quite similar to that (77.2%) proposed for whole cottonseed for large ruminants by NRC tables. Low digestibility of fiber (under 10% of NDF) and of nonfibrous carbohydrate limits the digestibility of DM and energy from ECS. (+info)
Effects of gossypol from cottonseed meal and dietary vitamin E on the reproductive characteristics of superovulated beef heifers.
Superovulated Hereford-Angus crossbred heifers (average 397 kg BW) were used to test the effect of feeding cottonseed meal (gossypol) and vitamin E on embryo quality and ovarian characteristics. Twenty-four heifers were assigned randomly to four treatments with six heifers per treatment. Treatments were the following dietary supplements: 1) SBM (soybean meal + 30 IU vitamin E/kg of diet DM); 2) SBM+E (soybean meal + 4,000 IU vitamin E x animal(-1) x d(-1)); 3) CSM (cottonseed meal + 30 IU vitamin E/kg of diet DM); and 4) CSM+E (cottonseed meal + 4,000 IU vitamin E x animal(-1) x d(-1)). Supplements based on cottonseed meal provided 43.5 g of total gossypol/d (37% negative isomer (-) and 63% positive isomer (+)). Blood samples were collected at the start of the experiment and every 3 wk thereafter up to 12 wk. Plasma a-tocopherol (alpha-T) concentration was affected by treatments (P < 0.05). Heifers supplemented with cottonseed meal had greater (P < 0.05) alpha-T concentration in plasma than heifers supplemented with soybean meal at each concentration of vitamin E. Supplementation at 4,000 IU vitamin E x animal(-1) d(-1) increased (P < 0.05) the concentration of a-T in plasma. Weight gain, hemoglobin and hematocrit were not affected by treatment. Erythrocyte osmotic fragility (EOF) increased (P < 0.05) in cottonseed meal-fed animals; however, EOF was lowered (P < 0.05) with vitamin E supplementation. Heifers fed CSM and CSM+E supplements had greater (P < 0.01) concentrations of (-)-, (+)-, and total-gossypol in plasma, corpora lutea (CL), liver, and endometrium than heifers fed SBM and SBM+E supplements. Tissue alpha-T concentration increased with increased dietary supplemental vitamin E, particularly in great amounts in the CL. Because there was no adverse effect of gossypol on superovulation response or embryo development despite concentrations of gossypol in endometrium that are toxic to embryos, it is likely that systems exist in the reproductive tract to limit gossypol toxicity. (+info)
Validity of specifically applied rare earth elements and compartmental models for estimating flux of undigested plant tissue residues through the gastrointestinal tract of ruminants.
The validity of using rare earth elements as flow markers of undigested residues was evaluated by comparing mean gastrointestinal residence time (GMRT) of rare earths specifically applied to cottonseed hulls (CSH) to that of the indigestible fiber of CSH. Feces were collected from five lambs fed a mineral supplemented diet of CSH containing 52 g CP/kg DM and five lambs fed a CSH plus cottonseed meal diet (CSH+CSM) containing 123 g CP/kg DM. Rare earth elements (La, Yb, and Tb) specifically bound to CSH were included in the diet for a 5-d period and then deleted from the diet for a 3-d period. Following the last fecal collection, lambs were slaughtered for collection of digesta from segments of the gastrointestinal tract. Potentially indigestible NDF (PIF) was determined in diets and digesta from each segment of the gastrointestinal tract. Mean turnover rate, time delay, and GMRT for each rare earth element was estimated by fitting an age-dependent compartment model to profiles of markers appearing in the feces (compartmental model-marker method, CMM). The GMRT also was computed by the indigestible entity pool dilution method (IEPD) as grams of PIF in sampled segment/mean intake rate of PIF proceeding slaughter, g/h. The GMRT computed by the CMM and the IEPD methods did not significantly (P < 0.05) differ (99.6 vs 94.8 h and 58.9 vs 59.5 h for CMM vs IEPD and CSH and CSH+CSM diets, respectively). Regression of GMRT estimated for rare earths vs PIF yielded a highly significant regression (P = 0.001) with a regression coefficient of 0.94 +/- 0.016. It was concluded that rare earth elements applied to specific feeds are valid flow markers for the undigested residues derived from such marked feeds. (+info)