SULFUR METABOLISM IN RUMINANTS. II. IN VIVO AVAILABILITY OF VARIOUS CHEMICAL FORMS OF SULFUR

Transcription

1 SULFUR METABOLISM IN RUMINANTS. II. IN VIVO AVAILABILITY OF VARIOUS CHEMICAL FORMS OF SULFUR T. S. Kahlon, J. C. Meiske and R. D. Goodrich University of Minnesota, St. Paul a,b SUMMARY Lambs fed semipurified diets supplemented with DL-methionine, hydroxy analog of methionine, calcium sulfate, sodium sulfate or elemental sulfur gained faster, consumed more dry matter, and digested and retained greater weights of nitrogen and sulfur (P<.01) than lambs fed a sulfur deficient diet. Lambs fed a sulfur deficient diet had severe weight losses in 40 days and were removed from the experiment. Lambs fed hydroxy analog of methionine had more (P<.05) wool growth than lambs fed elemental sulfur (33.2 vs 27.1 mm). Apparent dry matter digestibilities ranged from 76.1 to 80.9% for the various treatments. When expressed as a percent of intake, apparent nitrogen digestibilities were not affected by sulfur treatments, however lambs fed sulfur from each of the supplemental sulfur sources retained higher percentages (P<.01) of the nitrogen consumed than control lambs. Sulfur supplementation also improved the utilization of digested nitrogen. With the exception of lambs fed elemental sulfur, those fed sulfur from each of the sulfur sources digested greater percentages (P<.01) of their dietary sulfur than lambs fed a diet with no added sulfur. However, the lambs fed elemental sulfur retained a higher (P<.01) percent of digested sulfur than those fed the other sulfur sources. Sulfur retentions of lambs supplemented with sulfur varied from 48.5 to 61.8% during the initial 20 days of feeding, but varied from 31.5 to 39.4% during the third 20-day period. The reduced variation among lambs fed the various sulfur sources and the decline in percentages of sulfur that were retained suggests that body saturation with sulfur may have occurred after the initial 20 days. (Key Words: Sulfur Metabolism, Ruminants, Sulfur Availability In Vivo.) INTRODUCTION Protein-rich feeds normally provide adequate sulfur to meet the requirements of ruminants. Replacement of these feeds with nonprotein nitrogen has increased the possibility of a sulfur deficiency. Supplementation of sulfur deficient rations with methionine, sodium sulfate and elemental sulfur has been shown to have beneficial effects. The value of other sulfur-containing compounds as sources of supplemental sulfur has not been well established. A 60-day growth trial was conducted with lambs to determine the influence of sulfur source on growth, dry matter intake, wool production and apparent digestibility and retention of sulfur and nitrogen. EXPERIMENTAL PROCEDURE Thirty-six crossbred lambs with an average initial weight of 32.8 kg were randomly allotted to one of six sources of dietary sulfur (DLmethionine, hydroxy analog of methionine, calcium sulfate, sodium sulfate, elemental sulfur or no added sulfur). Each lamb was injected intramuscularly with 500,000 IU of vitamin A, Ingredient TABLE 1. COMPOSITION OF THE BASAL DIET a Percent b Ground oat straw Corn oil 3.00 Urea 4.20 Dextrose Corn starch amineral analyses:.034% S,.083% Ca,.056% P, apaper No of the Scientific Journal Series of.349% K,.043% Mg,.9 ppm Cu, 72.5 ppm Fe and the Minnesota Agricultural Experiment Station ppm Mn. bdepartment of Animal Science. bcomposition on an as fed basis JOURNAL OF ANIMAL SCIENCE, Vol. 41, No. 4, 1975

2 SULFUR METABOLISM IN RUMINANTS 1155 Ingredient TABLE 2. COMPOSITION OF THE MINERAL SUPPLEMENT a Percent K 2 CO CaHPO 4.2 H~O 16.8 NaC MgO FeSO 4 o7 H MnSO 4.H~O.12 Na 2 B40 ~ "i0 H~O.264 ZnSO 4-7 H CuSO~ 05 H Na 2 MoO 4,2 H CaF KI CoCI 2.6 H CrC13 "6 H Na 2 SeO Starch acalculated to provide the following amounts per lamb daily when 100 g were fed: g K, 6.92 g CI, 4.52 g Na, 3.91 g Ca, 3.02 g P, 1.20 g Mg,.27 g S, 96.4 mg Fe, 41.0 nag Zn, 39.0 nag Mn, 30.0 nag B, 12.2 mg Cu, 2.4 mg Mo, 1.2 nag F,.8 nag I,.36 rng Co,.14 mg Cr, and.13 mg Se. Mineral analyses:.274% S, 2.38% Ca, 2.75% P, 9.38% K,.945% Mg, 79.9 ppm Cu, 2101 ppm Fe, 17.1 ppm Mo and 333 ppm Mn. 75,000 IU of vitamin D and 50 IU of vitamin E. The lambs were placed in conventional metabolism stalls and were fed 100 g of a mineral supplement plus ad libitum amounts of basal diet. Water was offered once daily for 1 hour. The composition of the basal diet is presented in table 1. The mineral supplement was formulated with reagent grade mineral salts and provided adequate amounts of all minerals except sulfur. Starch was used as a carrier in the mineral supplement. The composition of the mineral supplement is shown in table 2. After a 20-day pretrial period, during which the lambs were fed the basal ration and mineral supplement with no added sulfur, a 60-day experimental period was initiated. The experimental period was divided into three 20-day periods. On day zero of the experimental period an area of skin on the upper right side of the rump was shorn and marked for wool growth measurements, the lambs were weighed and were fed their respective treatment diets. Amounts of sulfur supplied per lamb daily by 100 g of the mineral supplement are shown in table 3. Aliquots of urine and feces were collected and composited to form three 20-day samples for each lamb. The Iambs were weighed every 20 days and wool samples were collected after 60 days. Control lambs were removed from treatment after 40 days because of very poor growth. The basal ration, mineral supplement, feces and urine were analyzed for nitrogen by the macro-kjeldahl procedure (A.O.A.C. 1970). Total sulfur in the various samples was determined using a modification of the A.O.A.C. (1970) method. The modification consisted of adding.5 g of barium chloride to the dissolved ash and shaking the samples for 5 minutes. After standing for 2 min, turbidity was measured at 500 millimicrons. Standard curves were prepared for each sulfur source and respective k values (mg of S/unit optical density) were used to quantitate amounts of sulfur in the various mineral supplements. A k value which was the average of the k values for DL-methionine and sodium sulfate was used to calculate sulfur contents of feed, feces and urine. Statistical analyses were conducted for each period using analyses of variance and Duncan's new multiple-range test (Steel and Torrie, 1960). TABLE 3. AMOUNT OF SULFUR SUPPLIED PER LAMB DAILY BY 100 g OF THE MINERAL SUPPLEMENT Amount of No. of lambs Treatment sulfur, g per treatment Control DL-methionine a Hydroxy analog of methionine a Calcium sulfate Sodium sulfate Elemental sulfur a alambs removed from treatment during the pretrial period due to injury or failure to consume feed.

3 1156 KAHLON, MEISKE AND GOODRICH RESULTS AND DISCUSSION Lambs fed each of the sulfur sources gained fasted (P<.01) and consumed more (P<.01) dry matter than control lambs (table 4). For the entire 60-day period, there were no significant differences among weight gains or dry matter consumptions of lambs fed the various sulfur sources. Chalupa et al. (1973) reported similar observations with cattle. Mowat and Deelstra (1970) reported that weight gains of lambs increased by 12% when.4% methionine was added to a corn and alfalfa ration that was supplemented with urea. From 0 to 40 days the Iambs fed the diet with no added sulfur had weight losses that averaged 149 g per day. Most of this weight loss occurred during the 20 to 40-day period. Due to the severe weight losses, the control lambs were removed from the trial at 40 days. Dry matter consumptions by the control lambs were less than half as much as those of lambs which were supplemented with sulfur. For the 60-day period, amounts of feed consumed per kilogram of gain ranged from 6.07 to 7.04 for lambs fed the various sulfur sources (table 4). The lowest value was for lambs fed calcium sulfate and the highest feed to gain ratio was for Iambs fed elemental sulfur. Garrigus et al. (1953) found that the addition of elemental sulfur to a ration low in sulfur increased feed utilization by lambs. Dry matter digestibility values ranged from 76.1 to 80.9% TABLE 4. PERFORMANCE DATA OF LAMBS FED A SEMIPURIFIED DIET SUPPLEMENTED WITH VARIOUS SULFUR SOURCES Sulfur source Hydroxy DL- analog of Calcium Sodium Elemental Item Control methionine methionine sulfate sulfate sulfur No. Iambs Daily gmn, g 0-20 days -38 b 288 a 171 a 166 a 221 a 193a 20-40days -260 b 53a 68 a 100 a -24 a 64 a days days.149b 170 a 119 a 133a 99 a 128 a 0-60 days Daily dry m~terintake, g 0-20 days 655b 1140 a 1005 a 985 a 1070 a 1045 a 20-4Odays 300b 1145 a 1055 a 1015 a 960 a 1220 a days days 478b 1145 a 1028 a a 1133 a 0-60 days Dry matter per kg gain, kg 0-20 days days days days days day wool growth, mm c d Dry matter digestibility, % 0-20 days 78.1 d c 80.9 c days days days 77.8 d ce 80.0 ce 79.6 c 77.9 f 0-60 days f 79.7 c 80.1 ce 79.4 c 77.9 d a'bvalues within rows with different letters differ significantly (P<.01). c'dvalues within rows with different letters differ significantly (P<.05). e'fvalues within rows with different letters differ significantly (P<.05).

4 SULFUR METABOLISM IN RUMINANTS 1157 (table 4). Barton et al. (1971) observed that the addition of' sulfur to a sulfur deficient in vitro system improved the digestibility of cellulose and lignocellulose. McLaren et al. (1965) did not observe an influence of methionine supplementation on the digestibility of organic matter or crude fiber by sheep fed a semipurified diet. Lambs fed the diet that was supplemented with hydroxy analog of methionine had greater (P<.05) wool growths (33.2 ram) than lambs fed elemental sulfur (27.1 mm). Apparent nitrogen digestibilities (table 5) were not significantly influenced by treatments when expressed as percentages of nitrogen intake. However, lambs fed diets that contained supplemental sulfur consumed more nitrogen than controls and consequently they digested greater weights of nitrogen. Lambs fed supplemental sulfur, from any of the sulfur sources, retained significantly (P<.01) more nitrogen (expressed either in grams or as a percent of nitrogen intake) than the control lambs. Nitrogen retention values for lambs fed the various sulfur sources did not differ significantly. These data show that supplementation of a low sulfur diet with sulfur results in a reduction in urinary TABLE 5. NITROGEN METABOLISM DATA OF LAMBS FED A SEMIPURIFIED DIET SUPPLEMENTED WITH VARIOUS SULFUR SOURCES Sulfur sources Hydroxy DL- analog of Calcium Sodium Elemental Item Control methionine methionine sulfate sulfate sulfur No. lambs N intake per lamb, g per day 0-20 days c a b b a b days 5.32 c a a a a a days days 9.26 c a a a a a 0-60 days N digested per lamb, g per day 0-20 days c a b b b days 3.85 c a a a a a days days 7.18 c a a a a a 0-60 days N retained per lamb, g per day 0-20 days 3.01 c 9.13 a 8.06 a 7.74 a 8.71 a 8.68 a days -.20c 8.72 a 8.14 a 7.41 a 6.56 a 9.23 a days days 1.40 c 8.92 a 8.10 a 7.58 a 7.63 a 8.95 a 0-60 days N digestibility, % 0-20 days days days days 76~ days N retention, % of intake 0-20 days 21.8c 37.8 a 38.8 a 37.4 a 38.8 a 40.4 a days e 35.8 a 37.0 a 33.6 a 29.7 a 36.2 a days days 12.8 c 36.8 a 37.9 a 37.1 a 36.2 a 38.2 a 0-60 days a'cvalues within rows with different letters differ significantly (P<.01). b'cvalues within rows with different letters differ significantly (P<.05).

5 1158 KAHLON, MEISKE AND GOODRICH nitrogen loss. During the 20 to 40-.day period, control lambs digested 65% of the nitrogen that they consumed, however they lost 107.2% of their digested nitrogen and were in a negative nitrogen balance. This suggests that the nitrogen which was absorbed by the control lambs was either not available or it was not incorporated into body tissues due to a lack of sulfur. Similar observations have been reported by Loosli and Harris (1945), Lofgreen. et al. (1947), Albert et al. (1955), McLaren et al. (1965) and Bull and Vandersall (1973). Sulfur digestibility and retention data are presented in table 6. With the exception of lambs fed elemental sulfur, lambs fed supplemental sulfur digested higher (P<.01)percentages of their dietary sulfur than those fed no added sulfur during the 0 to 20-, 20 to 40- and 0 to 40-day periods. During the 0 to 20-day period, lambs fed hydroxy analog of methionine or calcium sulfate digested more (P<.01) sulfur than Iambs fed elemental sulfur. Lambs fed DL-methionine, hydroxy analog of methionine, calcium sulfate or sodium sulfate digested TABLE 6. SULFUR METABOLISM DATA OF LAMBS FED A SEMIPURIFIED DIET SUPPLEMENTED WITH VARIOUS SULFUR SOURCES Sulfur sources Hydroxy DL- analog of Calcium Sodium Elemental Item Control methionine methionine sulfate sulfate sulfur No. lambs S intake per lamb, g per day 0-20 days.44 c 1.64 a 1.59 a 1.58 a 1.63 a 1.62 a days.26 c 1.65 a 1.61 a 1.61 a 1.60 a 1.68 a days days " " days S digested per lamb, g per day 0-20 days.21 c 1.20 ad 1.30 ad 1.21 ad 1.19 ad.87 ae days.10 c 1.02 ad 1.05 ad 1.04 ad 1.06 ad.62 ae days a.94 a.92 a.90 a.63 c 0-40 days.15 c 1.11 ad 1.17 ad 1.13 ad 1.13 ad.75 ae 0-60 days a 1.09 a 1.06 a 1.05 a.71 c S retention per lamb, g per day 0-20 days.16 c.89 a.99 a.90 a.79 a.80 a days.05 c.65 a.65 a.66 a.62 a.53 a days a b days " " ill e.77 d.82 ad.78 d.71 d.67 bd 0-60 days a b S digestibility, % 0-20 days 47.2 c 73.3 a 81.3 ad 77.1 ad 73.2 a 53.9 e days 38.0 c 62.4 a 65.2 a 65.5 a 66.9 a 37.0 c days a 52.9 a 53.9 a 36.0 c 0-40 days 42.8 c 67.7 a 73.2 a 71.2 a 69.6 a 46.8 c 0-60 days a 67.1 a 64.6 a 64.0 a 43.0 c S retention, % of intake 0-20 days 36.5 ca 54.4 b 61.8 a 56.9 a days days 30.8 a 39.4 b 32.8 a 31.5 a 0-40 days 2819 c 46.7 a 51.1 a 49.0 a 43.0 a 0-60 days b a a 41.8 a 37.9 a a'cvalues within rows with different letters differ significantly (P<.01). a'bvalues within rows with different letters differ significantly (P<.05). d'evalues within rows with different letters differ significantly (P<.01).

6 SULFUR METABOLISM IN RUMINANTS 1159 more (P<.01) sulfur than the lambs fed elemental sulfur during the 20 to 40-, 0 to 40- and 0 to 60-day periods. This was also true during the 40 to 60-day period, except that sulfur digestibilities by lambs fed DL-methionine did not differ significantly from those for lambs fed elemental sulfur. Fifty-seven percent of the dietary sulfur from elemental sulfur was lost via the feces, whereas the fecal loss of sulfur from the other sulfur sources ranged from 32.9 to 40.!%. Similar observations were made by Johnson et al. (1970). They found that 63.4% of the sulfur in elemental sulfur was lost in the feces, but fecal losses of only 21.8 and 20.4% occurred when sodium sulfate or methionine were fed. Bull and Vandersall (1973) also reported similar fecal losses for sodium sulfate and DL-methionine. During the 0 to 20-day period Iambs fed hydroxy analog of methionine (P<.01), calcium sulfate (P<.01) or DL-methionine (P<.05) retained a higher percentage of their sulfur intakes than the control lambs. Lambs fed hydroxy analog of methionine retained more (P<.05) sulfur than lambs fed the other sulfur sources during the 40 to 60-day period. For the 0 to 60-day period sulfur retentions by Iambs fed hydroxy analog of methionine were greater (P<.05) than those by lambs fed sodium sulfate or elemental sulfur. During the 40 to 60-, 0 to 40- and 0 to 60-day periods lambs fed elemental sulfur 9 retained higher (P<.O1) percentages of their digested sulfur than Iambs fed other sulfur sources, except that the difference between lambs fed elemental sulfur and hydroxy analog of methionine was significant at the 5% level of probability during the 40 to 60-day period. Apparent sulfur digestibilities by lambs fed elemental sulfur or sodium sulfate were 43.0 and 64.0% and apparent sulfur retention values were 37.9 and 39.0%, respectively. Johnson et al. (1971) reported true digestibility values of 36.0 and 77.8% and true retention values of 26.8 and 56.0% for Iambs fed elemental sulfur and sodium sulfate, respectively. Goodrich and Tillman (1966) reported lower retention values for elemental sulfur (24.5%) and sodium sulfate (32.7%) than the values reported here. In agreement with our data, Bouchard and Conrad (1973) observed that sulfur from calcium sulfate was absorbed as well as sulfur from sodium sulfate. Kahlon et al. (1975) measured sulfur availability using an in vitro system. They reported relative sulfur availabilities (L-methionine set at 100) of: L-methionine, 100; DL-methionine, 63.0; hydroxy analog of methionine, 28.8; calcium sulfate, 94.1; sodium sulfate, 55.4; ammonium sulfate, 93.0; sodium sulfide, 42.6 and elemental sulfur, 35.8 percent. Thus, the in vitro system ranked sodium sulfate well above elemental sulfur in its ability to furnish available sulfur, but the present in vivo sulfur retention data ranked both sulfur sources about equal in their ability to furnish available sulfur. In contrast, Hale and Garrigus (1953), Albert et al. (1956) and Johnson et al. (1971) suggested that sulfate-sulfur may be utilized better than elemental sulfur. In the in vitro studies reported by Kahlon et al. (1975) sulfur from hydroxy analog of methionine was only 28.8% as available as that from L-methionine. However, in the present in vivo study, lambs fed hydroxy analog of methionine had higher sulfur retentions than those fed any of the other sulfur sources. Thus, the results of these two studies support the premise that rumen microorganisms do not degrade hydroxy analog of methionine readily (Belasco, 1972), but it is utilized by mammalian tissues. In contrast, Polan et al. (1970) and Holter et al. (1972) have shown that dairy cows fed hydroxy analog of methionine had increased digestibilities of crude fiber. Also, the feeding of hydroxy analog of methionine has resulted in higher protozoa populations in sheep (Patton et al., 1970). LITERATURE CITED Albert, W. W., U. S. Garrigus, R. M. Forbes and W. H. Hale Modified urea supplements with corn silage for wintering ewe lambs. J. Anim. Sci. 14:143. Albert, W. W., U. S. Garrigus, R. M. Forbes and H. W. Norton The sulfur requirement of growing-fattening lambs in terms of methionine, sodium sulfate and elemental sulfur. J. Anita. Sci. 15:559. A.O.A.C Official Methods of Analysis (llth Ed.). Association of Official Agricultural Chemists, Washington, D. C. Barton, J. S., L. S. Bull and R. W. Hemken Effects of various levels of sulfur upon cellulose digestion in purified diets and lignocellulose digestion in corn fodder pellets in vitro. J. Anim. Sci. 33:682. Belasco, I. J Stability of methionine hydroxy analog in rumen fluid and its conversion in vitro to methionine by calf liver and kidney. J. Dairy Sci. 55:353. Bouchard, R. and H. R. Conrad Sulfur requirement of lactating dairy cows. II. Utilization of

7 1160 KAHLON, MEISKE AND GOODRICH sulfates, molasses and lignin-sulfonate. J. Dairy Sci. 56:1429. Bull, L. S. and J. H. Vandersall Sulfur source for in vitro cellulose digestion and in vivo ration utilization, nitrogen metabolism and sulfur balance. J. Dairy Sci. 56:106. Chalupa, W., R. R. Oltjen and D. A. Dinius Sulfur nutrition for urea-fed cattle. J. Anim. Sci. 37:340 (Abstr.). Garrigus, U. S., W. G. Kammlade, L. E. Boley and H. Hardenbrook, Jr A study of elemental sulfur and of some other suggested preventives of enterotoxemia in a lamb fattening ration. J. Anita. Sci. 12:474. Goodrich, R. D. and A. D. TiUman Effects of sulfur and nitrogen sources and copper levels on the metabolism of certain minerals by sheep. J. Anim. Sci. 25:484. Hale, W. H. and U. S. Garrigus Synthesis of cystine in wool from elemental sulfur and sulfate sulfur. J. Anim. Sci. 12:492. Holter, J. B., C. W. Kim and N. F. Colovos Methionine hydroxy analog for lactating dairy cows. J. Dairy Sci. 55:460. Johnson, W. H., R. D. Goodrich and J. C. Meiske Appearance in the blood plasma and excretion of 3 s S from three chemical forms of sulfur by lambs. J. Anim. Sci. 31:1003. Johnson, W. H., R. D. Goodrich and J. C. Meiske Metabolism of radioactive sulfur from ele- mental sulfur, sodium sulfate and methionine by lambs. J. Anim. Sci. 32:778. Kahlon, T. S., J. C. Meiske and R. D. Goodrich Sulfur metabolism in ruminants. I. In vitro availability of various chemical forms of sulfur. J. Anim. Sci. 41:1147. Lofgreen, G. P., J. K. Loosli and L. A. Maynard The influence of protein source upon nitrogen retention by sheep. J. Anita. Sci. 6:343. Loosli, J. K. and L. E. Harris Methionine increases the value of urea for lambs. J. Anita. Sci. 4:435. McLaren, G. A., G. C. Anderson and K. M. Barth Influence of methionine and tryptophan on nitrogen utilization by lambs fed high levels of non-protein nitrogen. J. Anim. Sci. 24:231. Mowat, D. N. and K. Deelstra Encapsulated methionine supplement for lambs. J. Anim. Sci. 31:1041. (Abstr.). Patton, R. A., R. D. McCarthy, L. G. Keske, L. C. Grid, Jr. and B. R. Baumgardt Effect of feeding methionine hydroxy analog on the concentration of protozoa in the rumen of sheep. J. Dairy Sci. 53:933. Polan, C. E., P. T. Chandler and C. N. Miller Methionine analog effect on ruminant digestion. J. Anita. Sci. 31:251. (Abstr.). Steel, R. G. D. and J. H. Torrie Principles and Procedures of Statistics. McGraw-Hill Book Company, Inc., New York.