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Influence of Yucca Extract on Ruminal Metabolism in Cows

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Influence of Yucca Extract on Ruminal Metabolism in Cows Powered By Docstoc
					               Influence of yucca extract on ruminal metabolism in cows

        Z. Wu, M. Sadik, F. T. Sleiman, J. M. Simas, M. Pessarakli and J. T. Huber


                              J Anim Sci 1994. 72:1038-1042.




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     Influence of Yucca Extract on Ruminal Metabolism in COWS^^^^^

  Z. Wu, M. Sadik, F. T. Sleiman4, J. M. Simas, M. Pessarakli, and J. T. Hubers
                     Department of Animal Sciences, University of Arizona, Tucson 85721



ABSTRACT:         Two trials were conducted to deter-                     the respective treatments. Ruminal measurements
mine the influence of yucca extract on ruminal                            were not affected by treatment ( P > .lo). In Trial 2,
digestion, fermentation, and ammonia patterns using                       five cows were used in a 5 x 5 Latin square with
ruminally and duodenally cannulated dairy cows. In                        7-d periods. Treatments were 0, 2, 4, 6, and 8 g/d of
Trial 1, urea at 0 or 1%of the diet and yucca extract at                  yucca extract administered via ruminal cannulas.
0 or 4 g/d formed four dietary treatments in a 2 x 2                      Ruminal fluid was sampled 0, 1, 2, 4, 7, 11, 16, and 22
factorial arrangement. The experimental design was a                      h after feeding during the last 2 d of each period.
4 x 4 Latin square with 15-d periods. Duodenal
                                                                          Average ruminal NH3 N ranged from 31.4 to 35.4 mg/
digesta were sampled every 6 h during the last 4 d of
each period t o determine OM and ADF digestibilities                      dL, pH 5.99 to 6.18, and total VFA from 120 to 129
and bacterial protein synthesis in the rumen using                        mM, and all did not differ among treatments ( P >
Cr2O3 and 15N markers. Ruminal digestibilities were                       .lo). Yucca extract administered at 4 g/d did not
(percentage): OM 46.3 vs 43.0%, and ADF 35.9 vs                           significantly affect ruminal digestibilities of OM and
41.4%, with or without Deodorase@.Microbial protein                       ADF, and up to 8 g/d did not affect ruminal NH3, pH,
entering the duodenum averaged 2.7 vs 3.1 kg/d for                        or VFA.

    Key Words: Yucca shidigera, Ammonia, Rumen Metabolism, Lactating, Cows, Rumen Digestion

                                                                                                   J. Anim. Sci. 1994. 72:1038-1042


                        Introduction                                      NH3 odors in lagoons, ponds, and farms (Lyons,
                                                                          1992), and, when added to diets, increased BW gain of
   Yucca shidigera may have the ability to bind NH3                       growing pigs (Gippert, 1992) and decreased mortality
when ambient concentrations of NH3 are high and to                        in broiler chickens (Koyama, 1992). However, most of
release NH3 when concentrations are relatively low                        these studies have not been reported in refereed
(Lyons, 1992). Yucca extract (YE) is marketed under                       sources.
the names Sevarin@, Micro-Aid@ (Distributors                                 Large fluctuations in ruminal NH3 often result from
Processing, Porterville, CA), and Deodorase@                              the diurnal eating behavior of cattle (de Faria and
(Alltech, Nicholasville, KY). In all these the main                       Huber, 1984). Stable and adequate concentrations of
component is sarsaponin. Research showed stimula-                         ruminal NH3 ensure continuous availability to mi-
tory effects of sarsaponin added to diets on growth of                    crobes and allow for maximization of microbial protein
steers (Goodall and Matsushima, 1979; Goodall et al.,                     synthesis (Owens and Zinn, 1988). The binding
19791, weanling pigs (Cromwell et al., 19851, and                         compound in YE has been suggested to be
growing pigs (Foster, 1983a,b). Deodorase@reduced                         glycoprotein, but no evidence is available to indicate
                                                                          whether the glycoprotein is resistant to the microbial
                                                                          activity in the rumen. In vitro data from Arthaud and
    'Partially supported by Alltech, Inc., Biotechnology Center,          Wallace (unpublished) suggested that binding of NH3
Nicholasville, KY.                                                        by YE might be small. The objective of this study was
   'Research was conducted under a protocol approved by the               to determine the effect of YE on ruminal NH3 N
University of Arizona Institutional Animal Care and Use Commit-           concentrations, nutrient digestibilities, and microbial
tee.
   3The authors appreciate the assistance in conduct of the               protein production in lactating dairy cows.
experiments and laboratory analysis provided by P. Karem, C.
Fontes, F. Santos, J. Varela, S. Chan, P. Yu, and K. Chen. We thank
L. George-Smith for preparing the manuscript.                                                 Materials and Methods
   *American University of Beirut, 850 Third Avenue (18th Floor),
New York, NY 10022-6297.
   5To whom correspondence should be addressed: 205 Shantz Bldg.
                                                                            The YE used in this study was Deodorase@,which
   Received August 9, 1993.                                               was in powder form (92% DM) and contained 30%
   Accepted December 6, 1993.                                             Yucca shidigera extract (70% inactive carriers). The

                                                                     1038


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                                      YUCCA EXTRACT AND RUMINAL AMMONIA                                                    1039
  Table 1. Ingredient and chemical composition of                       d of each period 200 mg of l5N as ( I5NH4)$304 (10%
      diets fed to cows receiving yucca extract                         of N as I5N isototope) were added t o capsules. The
                                                                        Cr2O3 and 15N served as digesta and bacterial protein
Ingredient                         Trial 1             Trial 2          markers, respectively.
                                                                           Samples were taken from the TMD at preparation.
                                                                 ~




                                             % of DM
                                                                        During the last 4 d of each period, feed refusals were
Alfalfa hay                         24                  38
Grass hay                           24                   -              sampled daily, and approximately 500 mL of digesta
Whole cottonseed                     -                  12              was sampled every 6 h from duodenal cannulas. Half
Cottonseed hulls                     -                   4              of each duodenal sample was centrifuged at 2,000 x g
Sorghum graina                      49                   -
                                                                        to separate feed particles and protozoa and at 18,000 x
Corn                                 -                  21.8            g to isolate bacteria (Ohajuruka et al., 1991). The
Barley                               -                   6.9
Wheat mill run                       _.                  9.8
                                                                        other half of the duodenal sample was composited
Molasses                             -                   1.8            across all sampling times and kept at -5°C. Com-
Ureab                                -                   1.2            posited samples were thawed and dried at 50°C for 48
Minerals and vitamins                3                   4.5            h.
Nutrient content                                                           Bacteria from duodenal contents were isolated to
 CP                                 13.5                20.0
 ADF                                 -                  28.2            estimate intestinal passage of bacteria. Although
 NDF                                 -                  38.0            Kennedy et al. (1984) reported 13% greater enrich-
   aDry-rolled.
                                                                        ment of 15N in ruminal than in duodenal bacteria,
       Trial 1, 1%of urea was added to form another diet.               differences between treatments (chopped vs pelleted
                                                                        grass) were slightly higher for duodenal contents.
                                                                           Feed, orts, and duodenal digesta were analyzed for
recommended level for NH3 odor control in dairies is                    DM (100°C for 24 h ) , OM (550°C for 10 h ) , CP (N-C-
125 ppm of diet DM or approximately 2.5 g/d for a                       S Analyzer, NA 1500, Carlo Erba Strumentazine,
lactating cow consuming 20 kg/d DM.                                     Strada Rivoltana, Italy), ADF (Robertson and Van
                                                                        Soest, 19811, and Cr (Fenton and Fenton, 1979).
Trial 1                                                                 Additional analyses were total N in bacteria and 15N
                                                                        in duodenal digesta and bacteria (Pessarakli and
   Four lactating Holstein cows (650 k 20 kg BW)                        Tucker, 1985). Digesta and bacterial protein entering
fitted with duodenal T-type indwelling cannulas and                     the duodenum were calculated using marker ratio
ruminal fistulas received the following dietary treat-                  techniques.
ments in a 4 x 4 Latin square design: 1) control ( C ) ,                   Lactational parameters were not determined be-
2) control plus Y E ( YE), 3 ) control plus urea ( U),                  cause ruminal parameters were the major focus of the
and 4 ) control plus YE plus urea ( YE+U).  The C diet                  short-term Latin square experiment. Data were
contained 13.5% CP (Table 1 ) . Urea was added at 1%                    statistically analyzed using the ANOVA procedure of
of dietary DM, and YE was administered into the                         SAS (1985) for Latin square designs employing the
rumen through ruminal fistulas in gelatin capsules a t                  following model: Y = p + T + C + P + E, where Y =
4 g/d. This amount of YE was larger than the                            observation, p = population mean, T = treatment, C =
manufacturer’s recommended amount (2.5 g/d) for                         cow, P = period, and E = error. Separation of means,
NH3 odor control but was similar to the largest                         when interactions of YE x urea were found, used
amount used in the study of Goodall and Matsushima                      Duncan’s multiple-range test.
(19791, in which daily BW gain of steers was
increased by YE. Experimental periods were 15 d in                       Trial 2
length, which would allow for adaptation of ruminal
metabolism to the treatments. Grubb and Dehority                                                    +
                                                                           Five lactating cows (650 22 kg BW) were used in
( 1975) reported that ruminal microbial populations                     a 5 x 5 Latin square design. Cows were fed a TMD
were established 7 d after change of a 100% orchard-                    containing 1.2% urea t o ensure high concentrations of
grass diet to 40% orchardgrass and 60% corn for                         ruminal NH3 (Table 1). Feed was offered at 0600
sheep.                                                                  daily, with amounts adjusted for 10% refusal, and
   Cows were fed a total mixed diet (TMD) at 0600                       milking was at 0500 and 1700. At feeding, cows were
daily in amounts adjusted for 10% refusal and were                      administered 0, 2, 4, 6, or 8 g/d of YE in capsules via
milked at 0500 and 1700. Administration of YE was at                    ruminal fistulas for the 7 d of each period. During the
feeding in the morning and a t 1800, which was                          last 2 d of administration, ruminal samples were
approximately .5 h after cows commenced their second                    taken via the fistulas from the dorsal-cranial, ventral-
major meal of the day after the evening milking. This                   cranial, dorsal-caudal, and ventral-caudal regions of
schedule would allow for synchronization of Y E                         the rumen at 0, 1, 2, 4, 7, 11, 16, and 22 h after
availability with increased ruminal NH3. Each cap-                      feeding. Samples from the different ruminal sites were
sule administered throughout the experimental peri-                     mixed, strained through four layers of cheesecloth,
ods also contained 12 g of CrzO3 and during the last 6                  immediately measured for pH, and kept at -5°C for


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1040                                                                             WU ET AL.
                     Table 2. Feed intake, nutrient digestibilities, and duodenal protein flow in cows
                                       receiving urea and yucca extract in Trial 1

                                                                                              Treatmenta
                 Item                                              C                   YE                  U              YE+U              SEM~
                 DMI, kg/d                                        19.2                 17.7               17.2            20.2               .65‘
                 Ruminal digestibility, %
                  OM                                              45.5                 45.5               40.5            47.0              2.0
                     ADF                                          38.3                 32.3               44.5            39.5              3.3
                 Duodenal CP flow, kg/d
                  Total                                            4.29                 3.53               4.52            4.04              .37
                  Nonmicrobial                                     1.16                 1.00               1.49            1.17              .18
                  Microbial                                        3.13                 2.54               3.03            2.87              .55
                 Microbial efficiencyd                            22                   21                 25              21                2.0
                           ~         ~            ~           ~              ~     ~              ~        ~




                                                                                                      m+U= YE plus U.
                       aC = control diet; YE =yucca extract ( 4 g/d); U = urea added to the diet at 1%;
                       bNo main effects were detected ( P > .1).
                       ‘Urea and YE interaction ( P < .05): YE < C, but YE+U > U.
                       dMicrobial CP:DM truly digested in the rumen (g/kg).



approximately 12 h before analysis of NH3 N using the                                         Effects of amount of YE were further tested for linear,
procedure of Chaney and Marbach (1962). Also, the                                             quadratic, cubic, and quartic responses by orthogonal
0-, 2-, 4-, and 11-h samples were composited for the 2                                        polynomial contrasts.
d and analyzed for VFA concentrations (Palmquist
and Conrad, 1978) using GLC (model 3300; Varian
Associates, Walnut Creek, CAI. Feed sampling and
                                                                                                                            Results
analyses were as in Trial 1.
   Data were analyzed using the General Linear
                                                                                              Trial 1
Models procedures of SAS ( 1 9 8 5 ) for Latin square
designs for DMI employing the model as described for                                             There were no significant ( P > . l ) main effects in
Trial 1 and for Latin square split-plot designs for                                           Trial 1 (Table 2), although DMI decreased with Y E
ruminal N H 3 N, pH and VFA concentrations using the                                          added to the C diet but increased when YE was added
following model (observations were the average of 2                                           to the urea diet ( P < .05). Average apparent ruminal
d): Y i j = p + C; + Pj + Tk + H i + CHil+ THM+ CPTijk +
          ~                                                                                   digestibilities of OM were 46.3 vs 43.0%, and ADF
E i j ~ where Y = observation, p = population mean, C =
        ,                                                                                     35.9 vs 41.4%,with or without YE, respectively. There
cow, P = period, T = treatment, H = hour after feeding,                                       were no differences in amount or efficiency of synthe-
and the combinations are interactions. The interaction                                        sis of microbial protein associated with treatment, nor
CH served as the error to test whole-plot effects of C,                                       was ruminal digestion altered by YE whether or not
P, and T; CPT was used to test split-plot effect of H.                                        urea was added.


                     Table 3 . Ruminal NH3 N, VFA concentrations, and pH of cows receiving varying
                                            levels of yucca extract in Trial 2

                                                            Yucca extract, g/d                                                         Contrasta
Item                                       0            2                4             6              8           SEM            L    Q             C     QT
                                                                                                                                            P <
Ruminal
 NH3 N, mg/dL                            33.2         35.4           31.7          34.5           34.5            1.1        .15      .17           .01   .01
 PH                                       6.12         6.04           6.15          5.99           6.18            .07       .42      .01           .08   .01
 VFA, mh4
  Total                                  120          124           129           128            125              7          .25      .21           .84   .70
  Acetate ( A )                           78.2         79.6          82.8          83.5           80.7            5.0        .27      .25           50    .88
  Propionate ( P 1                        22.6         23.6          24.5          22.9           24.1            1.5        .33      .47           .26   .25
  Butyrate                                14.8         16.0          16.4          16.1           15.8              .9       .13      .04           .63   .85
  A:P                                      3.55         3.39          3.45          3.69           3.40             .13      .98      .84           .01   .30
DMI, kg/d                                 19.9         20.1          19.9          19.1           20.2             .9        .94      .73           .40   .65
   aL = linear, Q    = quadratic,   C = cubic, QT = quartic.


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Trial 2                                                                                     86

   There were no treatment x time interactions ( P >
.1) on ruminal NH3 N, pH (Figure 11, or I T A ;
therefore, treatment means reflect an average of all
sampling times (Table 3 1, which were not affected by
                                                                                      LI

                                                                                      d
                                                                                      2
                                                                                      -
                                                                                      z
                                                                                            84    (-\
                                                                                                  -


YE ( P > . 1quartic effects NH3 N, significant ( P < .01)
cubic and ) . For ruminal were shown, as were quad-                                              4i


ratic and quartic effects for ruminal pH. Moreover,                                   =
                                                                                      .r"   aa    -             \/\,,
there was a quadratic effect ( P < .04) for ruminal
butyrate concentration and a cubic effect ( P < .O 1)for
acetate:propionate ratio. Data averaged from treat-                                                                                    I
                                                                                            a2




                          Discussion




                                                                                    polynomial effects shown for ruminal measurements
                                                            a                       in Trial 2 seemed to be of little practical or physiologi-
                 po--Q--
      4 *e#{*:%.--        -0.
                                                                                    cal significance, because of generally small differences

      z
      p- ao -
                          .T-----T---             -___.
                                                   ______         -   -T
                                                                                    laboratory assays at high Y E concentrations (solu-
                                                                                    tions of > 5 mg/mL) (Arthaud and Wallace, unpub-
                                                                                    lished data; Headon, 1992). However, this binding is
                                                                                    extremely limited in comparison with the ruminal

                                                                                    lished data) estimated that the binding capacity of YE
                                                                                    was approximately 34 pg of NH3 N per gram of YE at
                                                                                    90% saturation. Considering that a maximum of 8 g/d
                                                                                    YE was administered to cows in Trial 2, and that
                                                                                    average ruminal NH3 N concentration was 34 mg/dL,
                                                                                    it is not surprising that YE did not change ruminal
                                                                                    NH3 N concentrations. The high ruminal NH3 N
                                                                                    concentrations might have overwhelmed the small
                                                                                    binding of NH3 by YE. However, it was originally
                                                                                    postulated that binding a t a level lower than 90%
          BJO'    "       "             "          '   '    "          '
             0    t   4         8       10   lt   14   10   11 10 tt                saturation might be useful in increasing efficiency of
                                                                                    NH3 fixation into microbial protein.
                      Hour after feeding                                               The Y E has been shown to reduce atmospheric NH3
                                                                                    in lagoons, ponds, animal manure (Giesy et al. 1992;
  Figure 1. Ruminal NH3 N (a) and pH (b) in cows                                    National Pig Research Institute, 19921, and pig
                                       4 (A), ( + ) ,or
administeredyucca extract at 0 (A),2 (0),   6                                       houses (Gippert, 1992), but concentrations of NH3 N
8 (H) g/d. SEM: Ruminal NH3 N , 1.1 mg/dL; ruminal                                  in these environments ( < 60 ppm) were much lower
pH, .07.                                                                            than in the rumen ( > 300 ppm in Trial 2).


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1042                                                              WU ET AL.

                         Implications                                       Goodall, S. R., and J. K. Matsushima. 1979. Sarsaponin effects upon
                                                                                ruminal VFA concentrations and weight gains of feedlot cattle.
                                                                                J. Anim. Sci. 49(Suppl. 1):371 (Abstr.).
   Administration of up to 8 g/d of yucca extract into                      Grubb, J. A., and B. A. Dehority. 1975. Effects of an abrupt change
the rumen of dairy cows fed diets containing 1.2% urea                          in ration from all roughage to high concentrate upon rumen
did not affect ruminal NH3 N concentrations (ranging                            microbial numbers in sheep. Appl. Microbiol. 30:404.
from 31.7 to 35.4 mg/dL), pH, or volatile fatty acids.                      Headon, D. R. 1992. From rain forests to deserts: New natural
At 4 g/d, yucca extract did not affect ruminal digestion                        components with far reaching effects from estrus synchroniza-
                                                                                tion to pollution control. In: T. P. Lyons ( E d . ) Biotechnology in
of organic matter, acid detergent fiber, crude protein,                         the Feed Industry. Proc. Alltech’s 8th Annu. Symp. p 273.
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Even though yucca extract at 125 ppm of diets has                           Kennedy, P. M., G. P. Hazlewood, and L. P. Milligan. 1984. A
reportedly reduced NH3 odors in certain environments                            comparison of methods for the estimation of the proportion of
and enhanced animal performance, it does not affect                             microbial nitrogen in duodenal digesta, and of correction for
                                                                                microbial contamination in nylon bags incubated in the rumen
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Description: Influence of Yucca Extract on Ruminal Metabolism in Cows