effects of lasalocid on growth, nutrient digestibility and rumen characteristics in chios lambs and...

Small Ruminant Research, 1 (1988) 217-227 217 Elsevier Science Publishers B.V., Amsterdam - - Printed in The Netherlands

Effects of Lasalocid on Growth, Nutr ient Digest ibi l i ty and Rumen Characterist ics in Chios Lambs and Damascus Kids

M. HADJIPANAYIOTOU, C. PAPACHRISTOFOROU and S. ECONOMIDES

Agricultural Research Institute, Nicosia (Cyprus)

(Accepted 28 November 1987 )

ABSTRACT

Hadjipanayiotou, M., Papachristoforou, C. and Economides, S., 1988. Effects of lasalocid on growth, nutrient digestibility and rumen characteristics in Chios lambs and Damascus kids. Small Rumin. Res., 1: 217-227.

Two feeding trials and one digestibility trial with early weaned Damascus kids (50 days of age ) and one feeding trial with early weaned Chios female lambs (42 days of age) were carried out to investigate the effects of lasalocid sodium (37.5 mg kg -1 feed as fed basis) on growth and incidence of coccidiosis. In the first feeding trial with kids, the effect of protecting the feeding troughs from being contaminated with faeces was also examined.

Both the protection of troughs and the addition of lasalocid sodium significantly improved growth of kids in the first trial. Feed utilization was also improved (11% ) when a lasalocid containing diet was fed. Addition of lasalocid increased propionate and decreased butyrate relative molar proportions in the rumen. Differences in acetate molar proportion, ruminal pH, NH3-N concentration or total VFA between the diets were not significant. In the second trial, kids fed the lasalocid diet tended to grow faster. Feed efficiency was also improved ( 7.6% ). In the third trial, lambs on the lasalocid containing diet grew faster, but there was no improvement in conversion efficiency. Digestion coefficients {determined with kids) of dry matter, organic matter and crude protein were 0.76, 0.77, 0.69 and 0.78, 0.79, 0.74 for the control and the diet containing lasalocid, respectively.

Four clinical cases of coccidiosis were reported in kids fed the control diet (unprotected troughs, no lasalocid) in the first trial and three cases in the no lasalocid diet in the second trial. In the trial with lambs, no clinical case of coccidiosis was recorded.

INTRODUCTION

A substantial amount of research has been conducted on various ionophores. Monensin, produced by Streptomyces cinnamonensis, and lasalocid, by Strep- tomyces lasaliensis, are the ones most widely studied. Both have been cleared for use in cattle in Europe (Braude, 1978) and the USA {Kenneth, 1982). Performance data on nearly 16 000 head used in feedlot trials, showed that

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cattle fed monensin-containing diets grew faster (1.6%), consumed less feed (6.4%) and required less feed per kg gain ( 7.5% ) than cattle fed control diets ( Goodrich et al., 1984). Information on the effects of ionophores fed to sheep and goats is rather limited, and recently there is growing interest in the inclu- sion of ionophores in diets of sheep (Horton et al., 1980; Paterson et al., 1983; Van Vuuren and Nel, 1983; Ricke et al., 1984; Baran et al., 1986); and goats (Hinkle and Graig, 1980; Shelton and Thompson, 1980; Mehrez et al., 1982; Beede et al., 1985, 1986).

The most consistent finding for ionophore feeding is the increased molar proportion of propionate with a concomitant decline in the molar proportion of acetate and butyrate in the VFA produced in the rumen (Bergen and Bates, 1984). A number of other effects such as protein sparing (Poos et al., 1979), reduced protein degradation in the rumen (Muntifering et al., 1981), cocci- diostatic activity ( Hinkle and Graig, 1980; Van Vuuren and Nel, 1983; Good- rich et al., 1984) and improved dry matter and crude protein digestibility (Horton et al., 1980), have also been associated with ionophore feeding.

The present studies were undertaken in order to investigate the effects of lasalocid sodium on the performance of growing Damascus kids and Chios lambs, to study rumen fermentation and apparent digestion coefficients in kids, and to compare the performance of kids receiving concentrate mixture from protected or unprotected feeding troughs.

MATERIALS AND METHODS

Three feeding trials (two with Damascus kids and one with Chios lambs) and one digestibility trial (with Damascus kids) were conducted. In all trials, two diets were used, one with and the other without lasalocid sodium. Lasalocid sodium (Avatec - trademark of F. Hoffman, La Roche and Co. ) was added to the pelleted (5 mm cubes) concentrate mixture to provide 37 mg kg- ~ mixture (as fed basis). The basic ingredients of the concentrate mixture (kg t - 1 ) were: barley grain 466, sorghum grain 310, soybean meal 164, wheat bran 50, lime- stone 7 and sodium chloride 3. A trace element-vitamin mixture (Vita 6, Vita Trace Nutrition Ltd., Cyprus ) was added ( 2 kg t - ~ ) to supply 6000 I.U. vitamin A, 1000 I.U. vitamin D3, 8.5 I.U. vitamin E, 25 mg Mn, 1.75 mg I, 45 mg Zn, 30 mg Fe, 2 mg Co and 60 mg Mg per kg concentrate mixture ( as fed basis). The lasalocid sodium was mixed into the trace element-vitamin mixture used for the t reatment diet. Animals had free access to water. Preweaning feeding and management of kids and lambs were as outlined by Hadjipanayiotou (1986 ) and Hadjipanayiotou and Economides (1986), respectively.

Trial I

Forty-eight Damascus kids (28 males and 20 females) weaned at 50 days of age were used in a 2 X 2 factorial arrangement of treatments. The two factors

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tested were type of feeding trough (protected vs. unprotected) and concentrate mixture (with or without lasalocid sodium ). The unprotected self-feeders have been described by Economides (1983). For the protected self feeders an ap- propriate wire (8 mm in diameter) was used. The wire bars which were of 23 cm length, were fixed on a metal frame at a distance of 26 cm. The fence wire was then fixed on the wooden trough.

Kids were randomly allocated according to liveweight and sex to one of four treatments. Animals of each t rea tment were housed and fed together. Kids were offered a concentrate mixture ad libitum and 100 g of lucerne hay per head daily. Kids were weighed at the beginning of the trial and once every fortnight during the 84 day experimental period. Feed offered was recorded twice and feed residues once a week. In all four trials, kids were visually checked daily (08.00 h) for symptoms of diarrhoea. Faecal samples were taken for counting oocysts (Blood et al., 1983 ) from all animals with liquid faeces.

Rumen liquor samples were taken from 20 animals (10 from each diet) 3 h after the morning feeding at the end of the experimental period, by means of a tube passed into the reticulo-rumen via the oesophagus and suction created by a vacuum pump. Rumen liquor samples were strained immediately after collection through two layers of fine muslin and the pH was measured immediately. For rumen ammonia nitrogen determination, 5 ml of 0.2 N HC1 were added to 5 ml of the strained rumen liquor. After mixing, the contents were centrifuged at 2000 rpm for 10 min. Two ml of the supernatant were distilled in a Buchi distillation apparatus after the addition of 4 ml of sodium tetrabor- ate followed by a little distilled water. The distillate was collected in a 50 ml conical flask with 5 ml of 1% boric acid and 3 drops of mixed indicator and was then t i t rated with 0.01 N HC1. Four ml of the strained rumen liquor was also mixed with 1 ml of deproteinizing solution (1 M crotonic acid in 2.5 M meta- phosphoric acid) and the sample retained for VFA analysis. All samples were stored at - 20 ° C until required. Analyses of VFA were performed using a Per- kin Elmer Sigma 1B gas liquid chromatograph, fitted with flame ionization detector. The glass column (180 cm × 2 mm) was packed with porapak type Q. Data for rumen NH3-N, pH and VFA were analysed by one-way analysis of variance and for other characteristics as a completely random design experiment with 2 X 2 factorial arrangement of treatments; the model accounted for sex as well (Steel and Torrie, 1960). In this and in subsequent trials, daily liveweight gains were est imated from the regression equation ofliveweight (Y) recorded fortnightly on age (X) .

Trial 2

Forty-six kids ( 20 males and 26 females) were used. Kids were divided into two groups on the basis of liveweight, and were randomly assigned to a concentrate mixture with or without lasalocid sodium. All feeding troughs were

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protected with a fence wire. Sexes were kept apart and animals were housed in adjacent pens. Feeding and management practices, and data collection were similar to Trial 1. The trial lasted from weaning (50 days) to 120 days of age. Data were analysed by two-way analysis of variance as outlined by Steel and Torrie (1960).

Trial 3

Eight male Damascus kids (4 per diet) of a mean liveweight of 21.7 kg and 78 days of age were used to determine digestion coefficients for dry matter, organic matter and crude protein. Following weaning ( 50 days of age ), the kids were group-fed the experimental diets for 28 days and then placed in metabolism crates designed for the separate collection of urine and faeces. The animals remained in the crates for 14 days. The first seven days served as an adaptation period and the other seven as the collection period. Animals were offered 0.1 kg of lucerne hay daily per head and a fixed concentrate allowance. The concentrate allowance was 10% lower than that consumed by kids of similar body weight (Trial 1) kept in groups and offered the same concentrates ad libitum along with 0.1 kg lucerne hay. The daily hay and concentrate allow- ances were offered in approximately two equal portions (07.30 and 13.30 h) from separate feed containers. Feed residues were collected the following morning. Samples of feed offered and refused were collected daily and bulked over the collection period for subsequent analyses. Ten percent of the daily output of faeces and urine was stored at - 2 0 ° C in order to provide a bulk sample for each animal at the end of the trial. Urine was collected in a plastic bucket containing 25 ml of 50% sulphuric acid. A representative sample of faeces was homogenized with approximately three times its weight of water, before being analysed for total nitrogen (macro-Kjeldahl). Chemical analyses on feeds, faeces and urine were made as outlined by AOAC (1975). Data collected were analysed by one-way analysis of variance ( Steel and Torrie, 1960).

Trial 4

Thirty-eight female Chios lambs were used. Animals were weaned from their dams at 42 days of age and were randomly allocated into two groups on the basis of their liveweight. The two groups were randomly assigned to a concentrate mixture with or without 37 mg lasalocid sodium per kg (as fed) mixture. Lambs were housed in two adjacent pens, and were offered concentrate ad libitum plus 0.1 kg lucerne hay per head daily. Feeding troughs (Economides, 1983) were not protected since lambs very rarely get into them. Lambs were weighed at the beginning and at the end of the trial, and once every fortnight during the course of the 63-day experimental period. Data collected were analysed by one-way analysis of variance ( Steel and Torrie, 1960).

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RESULTS

The chemical composition of feedstuffs used is shown in Table 1. Regression analysis used to test the weight gain curves for non-linearity showed that weight gain during the experimental period was linear in all three feeding trials.

TABLE 1

Chemical composition (g kg- ' DM) of feedstuffs

Component of diet Concentrate mixture Lucerne hay

Without With lasalocid lasalocid

Moisture (g kg -1 feed) 111 110 127 Crude protein 174 176 217 Crude fibre 51 47 - Crude fat 28 28 - Ash 60 59 103 Ca 10 10 - P 6.4 6.3 - Mg 2.4 2.4 -

TABLE 2

The effect of lasalocid sodium and type of feeding trough on the incidence of diarrhoea and the performance of growing Damascus kids (Trial 1 )

Concentrate mixture

Without lasalocid With lasalocid

Unprotected Protected Unprotected Protected trough trough trough trough

SE 1

and level of significance

Number of kids 12 12 12 11 Initial weight (kg) 14.3 14.4 14.4 14.5 Final weight (134 day) 33.1 36.0 37.5 38.5 Daily weight gain (g) 241 277 263 293 Feed intake (kg k id- 1 )

Concentrate 77 85 83 85 Hay 7.5 7.5 7.5 7.5

Feed DM/gain 3.9 3.7 3.5 3.4 Diarrhoea incidence

All cases 4 0 0 1 Coccidiosis 3 0 0 0

1.92 NS 2.65 LL

37 LL

In this and subsequent tables: NS, not significant; L, Lasalocid effect with P < 0.05; LL, Lasalocid effect with P < 0.01; SE = standard error of means.

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TABLE 3

Rumen metabolites in growing Damascus kids on concentrate mixtures with or without lasalocid sodium (Trial 1)

Concentrate mixture


SE and level of significance

Number of kids 10 10 Total VFA concentration (mmol l - ~ ) 74.9 69.5 11.4 NS Rumen NH:~-N (mg 1-1) 212 229 53 NS Rumen pH 6.1 6.0 0.17 NS Molar proportion

Acetate 47.4 43.3 2.3 NS Propionate 39.2 48.6 2.8 LL Isobutyrate 1.02 1.15 0.6 NS n-Butyrate 12.4 6.9 2.0 L

Trial I

A d d i t i o n o f l a s a l o c i d s o d i u m i m p r o v e d f i n a l w e i g h t ( P < 0.01 ) a n d d a i l y l iv-

e w e i g h t g a i n ( P < 0.01 ) o f k i d s ( T a b l e 2 ) . T h e p r e s e n c e o f l a s a l o c i d s o d i u m

in t h e c o n c e n t r a t e m i x t u r e d i d n o t h a v e a n y a d v e r s e e f f ec t o n i n t a k e ( T a b l e

2 ) . K i d s f ed t h e d i e t c o n t a i n i n g l a s a l o c i d s o d i u m c o n s u m e d m o r e f e e d w h e n

TABLE 4

Performance of growing Damascus kids on concentrate mixtures with or without lasalocid sodium (Trial 2 )

Concentrate mixture

Without lasalocid With lasalocid

Male kids Female kids Male kids Female kids


Number of kids 10 13 10 13 Initial weight (kg) 13.8 13.0 13.9 12.9 Final weight ( kg ) 33.5 26.9 35.1 27.8 Daily weight gain (g) 283 199 304 214 Feed intake (kg)

Concentrate 70 55 68 55 Hay 6.5 6.5 6.5 6.5

Feed DM/gain 3.4 3.9 3.1 3.7 Diarrhoea

All cases 2 5 0 1 Coccidiosis 1 2 0 0

1.62 NS 2.14L

33 NS

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TABLE 5

Effect of lasalocid sodium on diet digestibility and crude protein balance in growing Damascus kids (Trial 3)

Concentrate mixture



Number of kids 4 4 Dry matter intake (kg day- 1 ) 0.814 0.813 0.013 NS Digestibility of

DM 0.76 0.78 0.011 NS OM 0.77 0.79 0.012 NS CP 0.69 0.74 0.024 NS

CP intake (g day- ~) 148.6 145.7 2.32 NS CP absorbed (g day- ' ) 102.5 107.2 4.15 NS CP retained (g day- ~) 66.5 65.4 6.42 NS

the l a t t e r was of fered in u n p r o t e c t e d feeding t roughs . In addi t ion, lasalocid sod ium i m p r o v e d feed conve r s ion eff iciencies a n d reduced the incidence of d ia r rhoea /cocc id ios i s . T h i s was especia l ly ev iden t in the n o n - p r o t e c t e d feeding t rough. P r o t e c t i o n of feeding t r oughs t e n d e d to increase ( P < 0.08) the overal l g rowth ra te of kids (Tab l e 2) .

Tab le 3 shows m e a n s for r u m e n me tabo l i t e s . Addi t ion of lasalocid sod ium resu l ted in a s igni f icant increase ( P < 0.01 ) in the re la t ive m o l a r p r o p o r t i o n of p r o p i o n a t e and a decrease ( P < 0.05) in t h a t of n - b u t y r a t e . Reduc t ion in ace- t a t e m o l a r p r o p o r t i o n was no t s ta t i s t i ca l ly s ignif icant . Addi t ion of lasalocid

TABLE6

Performance of female growing Chios lambs on concentrate mixture with or without lasalocid sodium (Trial 4)

Concentrate mixture

Without With lasaloeid lasalocid


Number of lambs 19 19 Initial weight (kg) 15,1 15.2 Final weight (kg) 31,0 32.5 Daily weight gain (g) 252 275 Feed intake (kg lamb- 1 )

Concentrate 60 65 Hay 8.5 8.5

Feed, DM/gain 3.79 3.74

0.69 NS 1.09 NS

10 L

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sodium did not affect ruminal pH, NH:~-N concentration or total VFA concentration.

Trial 2

Kids on lasalocid sodium attained higher (P < 0.05) final body weight and tended to grow faster than those on the control diet. Lasalocid sodium did not affect concentrate intake but resulted in an improvement in feed conversion efficiency and a reduced incidence of diarrhoea (Table 4 ).

Trial 3

Adding lasalocid sodium to the concentrate mixture did not significantly alter digestion coefficients for DM (P<0.08), OM (P<0.08) , CP (P<0.10) and/or crude protein absorbed and retained (P < 0.20) (Table 5).

Trial 4

Lambs on the diet containing lasalocid sodium grew significantly faster (P < 0.05) than those on the control diet (Table 6), but differences between diets in final liveweight and feed to gain ratio were negligible. Lambs on the diet containing lasalocid sodium had a higher feed intake (8.3%) than those on the control. No clinical cases of coccidiosis were recorded.

DISCUSSION

Bergen and Bates (1984), reviewing the effects of ionophores on production efficiency and their mode of action, concluded that the most consistent effect of their feeding is an increased molar proportion of propionate with a concomitant decline in the molar proportion of acetate and butyrate in VFA produced in the rumen, resulting in an enhanced animal performance from the improved retention of carbon and energy from the rumen fermentation. In accordance with the data on cattle and sheep reviewed by Bergen and Bates (1984), and those of Beede et al. (1985) with growing goats, addition of lasalocid sodium to high concentrate diets fed to kids resulted in a significant increase in propionate molar proportion with a concomitant decline in the molar proportion of butyrate. The non-significant decrease in acetate molar proportion obtained in the present study may reflect acetate/butyrate interconversions (Leng, 1970). The lack of difference in total VFA concentration between the control diet and that supplemented with lasalocid sodium is in agreement with the data of Neuendorff et al. (1985) and Baran et al. (1986), but at variance with Hor- ton et al. (1980), who reported lower total ruminal VFA concentration in diets containing monensin. Ruminal fluid pH was not affected by lasalocid. Similar

225

findings have been reported by Horton et al. (1980) and Paterson et al. ( 1983 ). In accordance with data of Horton et al. (1980), ruminal ammonia concentration was not affected by ionophores. Contrary to the above reports, a reduction in ruminal ammonia concentration has been reported by others ( Hanson and Klopfenstein, 1979; Thompson and Riley, 1980). This reduction in ruminal ammonia concentration has been used to support the hypothesis that monensin reduces ruminal degradation of dietary protein (Poos et al., 1979).

Coccidiosis in kids over six weeks of age is considered the main cause of diarrhoea, anorexia and weight loss (Aumont et al., 1982 ). Monensin has been reported to be effective in suppressing clinical infections of coccidia in cattle ( Goodrich et al., 1984), lambs (Van Vuuren and Nel, 1983 ) and kids (Hinkle and Graig, 1980). In the present work, feeding lasalocid sodium reduced coccidiosis in kids. Diarrhoea/coccidiosis however was not a problem in lambs.

Based on experimental data obtained at the Cyprus Agricultural Research Institute ( Hadjipanayiotou, 1987), where lambs and kids were kept under similar feeding and managerial practices, it can be concluded that kids have greater nitrogen requirements and suffer more from coccidiosis than lambs. Thus, spe- cies differences obtained in the present study might reflect a protein sparing effect of lasalocid sodium and an effect in controlling subclinical coccidiosis, even at dosages similar to those approved for improving feed utilization. Fi- nally, the findings of the present study strongly suggested that feeding troughs suitable for sheep are not suitable for goats, and that in goat operations con- tamination of the feed should be prevented by trough protection.

The literature is not conclusive on the effect of ionophores on DM or CP digestibility of the diets. Significantly higher digestion coefficients for lambs fed monensin have been reported by Joyner et al. (1979) and Horton et al. (1980) and for steers by Beede et al. (1986). On the other hand, apparent DM digestibility was not affected by monensin feeding in cattle (Thompson and Riley, 1980), goats (Beede et al., 1985, 1986) or sheep (Poos et al., 1979; Pa- terson et al., 1983). In the present study, feeding lasalocid sodium tended to increase DM and CP digestibility. In the studies of Patterson et al. (1983), addition of lasalocid sodium increased N digestibility by 6%.

Based on the results of the present study, it is concluded that lasalocid sodium is a useful feed additive for growing kids but of limited value for growing lambs on high concentrate diets.

ACKNOWLEDGEMENTS

We thank L. Hadjiparaskevas, C. Photiou, A. Photiou, M. Theodoridou, M. Karavia, N. Parouti, S. Kourtellari and K. Kyprou for skilled technical assistance.

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