Technical Bulletin 145 ISSN 0070·2315

THE INFLUENCE OF FISH MEAL AND OF FORMALDEHYDE· TREATED SOYBEAN MEAL ON THE PERFORMANCE OF EARLY WEANED CHIOS

LAMBS AND DAMASCUS KIDS

M. Hadjipanayiotou

(Accepted November 1992)

TECHNICAL BULLETIN

AGRICULTURAL RESEARCH INSTITUTE

,jJ)1I~J;;I~Y OF AGRICULTURE AND NATURAL RESOURCES {'I ..j' ('(\

NICOSIA CYPRUS

Technical Bulletin 145 ISSN 0070-2315

THE INFLUENCE OF FISH MEAL AND OF FORMALDEHYDE· TREATED SOYBEAN MEAL ON THE PERFORMANCE OF EARLY WEANED CHIOS

LAMBS AND DAMASCUS KIDS

M. Hadjipanayiotou

(Accepted November 1992)

SUMMARY

Two trials with early weaned Damascus kids (52 days of age) and Chios lambs (42 days of age) were conducted. Ninety six Chios lambs and 79 Damascus kids were used in trial 1. In this experiment, four groups of males and four of females were randomly allocated to treatment diets (concentrate mixtures), which differed in the form of protein source used. A: untreated soybean meal (SB); B: formaldehyde (3 kg 40% formalde­hyde/t SB) treated SB (FSB); C: fish meal (FM) plus SB (FMSB); D: FM plus FSB (FMFSB). Eighty Chios lambs (40 males and 40 females) and 32 Damascus kids (16 males and 16 females) were used in trial 2. Only diets SB and FMSB were used in this experiment.

In both trials, animals were offered concentrates ad libitum along with 100 g of lu­cerne hay per head daily. Males performed better than females. Lambs attained higher daily liveweight gains (309 vs 266) and had better feed to gain ratio (4.16 vs 4.31) than kids. Protection of SB with formaldehyde reduced the effective dry matter and crude protein degradability of soya but did not improve daily bodyweight gain and/or feed to gain ratio in neither lambs nor kids. On the other hand, the presence of FM in the con­centrate mixture resulted in a significant improvement of liveweight gain and feed to gain ratio in kids, but not in lambs. Feed intake, expressed per kg body weight, was sim­ilar in lambs and kids. There were no significant differences in dry matter, organic mat­ter and crude protein digestibility, metabolizable energy concentration and crude pro­tein balance of the diets used in trial 1.

nEPIAH'I'H

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1

INTRODUCTION

New proposals for assessing the protein requirements of ruminant animals (Bur­roughs et al., 1975; Verite et al., 1979; ARC, 1980; 1984) rely upon the knowledge of both the portion of dietary protein escaping rumen degradation and the yield of microbial pro­tein synthesized in the rumen. The use of diets of high protein content for rapidly growing lambs and calves and high yielding dairy cows results in high concentrations of rumen ammonia-N, which cannot be effi­ciently utilized by rumen microorganisms. Excess ammonia is excreted in the urine. One way to improve ruminal protein output is to protect dietary protein from microbial degradation and/or select among protein sup­plements of low degradability.

Treatment of casein with formaldehyde to reduce degradation by rumen microorgan­isms has improved nitrogen utilization and performance in growing lambs (Faichney, 1971). The protection of protein supplements by this technique, however, has given varia­ble responses to production. Positive produc­tion responses in liveweight gain, resulting from the lnclusion of formaldehyde-treated soybean meai in all concentrate diets, have been reported by Thomas et ai. (1979), and Spears et ai. (1980), but no response has been obtained in other studies (Schmidt et ai., 1974).

Fish meal has been reported to be a pro­tein supplement of high quality and of low degradability. Studies conducted at the Row­ett Research Institute ( Preston et ai., 1965; Kay et ai., 1966) revealed higher nitrogen re­tention, improved weight gain and better feed efficiency in early weaned calves, when herring meal was used to replace groundnut meal as the main source of protein. Similar­ly, positive response to fish meal compared to oil-cake meal has been reported in calves by Ekern (1982).

The objective of the present work was to investigate the effect of feeding formalde­hyde-treated soybean or a combination of fishmeal with treated or untreated soybean meal on the performance of lambs and kids, the digestibility of the lamb diets and the de­gradability of the diets in the rumen.

MATERIALS AND METHODS

Two trials with early weaned Damascus kids (52 days of age) and Chios lambs (42 days of age) were conducted. Animals with­in species were stratified on the basis of live weight and age in uniform groups within each sex. Ninety six Chios lambs (52 males and 44 females) and 79 Damascus kids (40 males and 39 females) were used in experi­ment 1. Four groups of males and four of fe­males were randomly allocated to the treat­ment diets (concentrate mixtures), sexes kept apart. The treatment diets, which differed in the form of the main protein source used, were: A. untreated soybean meal (SB); B. formaldehyde-treated SB (FSB); C. fish meal (FM) plus SB (FMSB); D. FM plus FSB (FMFSB). Individual feed ingredients of the concentrates and their chemical analy­ses are shown in Table 1.

Formaldehyde (1.5 kg, 40% formalin) was dissolved in 38.5 I of water. The solu­tion was sprayed onto 500 kg of soybean meal, over a period of 10 min, while soya was mixed in a vertical mixer. After a fur­ther mixing of approximately 10 min the sprayed soybean meal was packed. into sealed polyethelene bags. Bags were opened after 48 h and the soybean meal was poured onto a plastic sheet at a depth of 3 to 5 cm and allowed to air-equilibrate for 72 h. Treated soybean meal was then processed in the concentrate mixtures (5 mm cubes) like the other protein supplements. Apparent di­gestion coefficients and nitrogen balance for the four diets used were determined using 4 male Chios lambs per diet. The animals were on the experimental diets for 21 days before being placed in metabolic crates for 14 days. The first seven days served as adaptation pe­riod and the other as faecal and urine collec­tion period. Collection, processing and anal­yses of feed, faeces and urine samples were made as outlined by Hadjipanayiotou (1982).

Eighty Chios lambs (40 males and 40 fe­males) and 32 Damascus kids (16 males and 16 females) were used in experiment 2. Ani­mals were divided into four groups (two male and two female) and were randomly al­located onto concentrate mixtures with or without fish meal (Table 1).

In both trials, animals were group-housed

2

Table 1. Fonnulation (g/kg as fed basis) and chemical analyses (g/kg DM) of the concentrate mixtures

Experiment 1 Experiment 2

Ingredients1 SB FSB FMSB FMFSB SB FMSB

Barley grain 776 776 822 822 800 846 SB 164 49 140 25 FSB 164 49 FM 69 69 69 Wheat bran 50 50 50 50 50 50 Limestone 7 7 7 7 7 7 Salt 3 3 3 3 3 3 Vitamin-trace element

mixture2

Chemical Analyses Crude protein 196 200 202 205 193 187 Ash 55 52 54 56 55 56

1 SB=Soybean meal; FSB=Fonnaldehyde treated soybean meal; FM=Fish meal. 2 Supplying per kg mixture (as fed) 6000 i.u. vit. A, 1000 Lu. vitamin D3,

8.5 Lu. vitamin E, 25 mg Mn, 1.75 1,45 mg Zn, 30 mg Fe, 2 mg Co, 60 mg Mg, and 37 mg lasalosid sodium.

in adjacent pens, sexes kept apart. They had free access to water and were offered con­centrates (5 nun cubes) ad libitum along with 0.1 kg of lucerne hay (180 g CP/kg DM) per head daily. Average daily liveweight gain was estimated from the regression of age on live weight, recorded fortnightly. Lambs and kids in trial 1 were on test for 56 (from 41 to 97 days of age) and 70 (from 56 to 126 days of age) days, respectively, whereas in the second trial, lambs (54 to 110 days of age) and kids (from 70 to 126 days of age) were on test for 56 days.

Performance data were analysed using different statistical models. Model I was used for analysing data within species and experiments and accounted for variation in diets, sexes and the interaction of diets by sexes. Model II accounted for variation in species (lambs and kids), diets (SB, FSB, FMSB and FMFSB), sexes (males and fe­males) and the interactions of species by diets and diets by sexes. Main effects were tested by the appropriate error terms and in­teractions by the residual error. Dependent variables examined were initial weight, final weight and daily weight gain. A similar model was used for the performance data of trial 2.

Rumen degradation studies Three mature Damascus goats (65 kg

body weight) fitted with permanent rumen cannulae were used. Animals were kept in individual pens with concrete floors bedded with wood shavings. The daily food allow­ance was composed of 0.6 kg concentrates, 0.2 kg barley hay and 0.2 kg lucerne hay. The concentrate mixtures used in experiment 1 were incubated in nylon bags in the rumen of the animals as outlined by Hadjipanayio­tou et ai. (1988) for degradability determina­tion.

Samples of mixtures were analysed for DM and CP before and after incubation. Three bags were incubated for each incuba­tion interval and the procedure was replicat­ed twice. The mean of the three bags per in­cubation interval was used for calculations. Processing of samples after withdrawal of bags from the rumen was as outlined by Hadjipanayiotou et ai. (1988). Loss of DM and CP at various incubation intervals was estimated by the exponential equation: p=a+b(l-e-ct) (Orskov, 1982), where p is the amount degraded at time t, a is the rapidly degradable fraction, b is the potential de­gradability at infinite time and c is the frac­tional rate constant at which the fraction b will degrade per hour. Data collected were analysed within trials by one-way analysis of variance as outlined by Steel and Torrie (1960).

3

r.

RESULTS

In both trials, males performed better than females in terms of liveweight gain and feed to gain ratio (Tables 2 and 3). Lambs at­tained higher daily liveweight gains than kids. Similarly, lambs required less concen­trates per kg bodyweight gain than kids ( 4.16 vs 4.31). However, male kids on diets FMSB and FMFSB required less feed per kg bodyweight gain than male lambs on the same diets.

Treatment of soybean meal with formal­dehyde reduced its effective DM and CP de­gradability (Table 4). There were significant differences between protein supplements for DM and CP degradability.

Protection of soybean meal with formal­dehyde did not improve daily bodyweight gain and/or feed to gain ratio in neither lambs nor kids (Table 2). On the other hand,

the presence of fish meal in the concentrate mixture resulted in a significant improve­ment of liveweight gain and feed to gain ra­tio in male kids, but not in lambs (Tables 2 and 3). Feed intake, expressed per kg body­weight, was similar.

There were no significant differences in dry matter, organic matter and crude protein digestibility, metabolizable energy concen­tration and CP balance of the diets used in either trial (Table 5).

DISCUSSION

Although in trial 2 smaller quantities of protein supplements were incorporated in the concentrate mixtures, nitrogen analysis did not show any difference in CP concentration between the mixtures used in the two trials due to differences in the nitrogen content of barley grain.

Table 2. Perfonnance of Chios lambs and Damascus kids offered concentrate mixtures with untreated soybean meal (SB), fonnaldehyde-treated soya (FSB), fish meal and SB (FMSB) or fish meal and FSB (FMFSB) as protein supplement (Experiment 1)

Daily Feed intake Feed/gai.n

Concen. mixture Sex Species

No. of animals

Initial weight

(kg)

Final weight

(kg)

Daily gain (g)

Concen. (g)

Lucerne hay (g)

Concen. Conc.+

hay

SB Male

Female

Lambs Kids Lambs Kids

13 10 11 9

15.7 16.2 14.5 13.9

34.5 36.4 30.2 30.3

335 289 280 234

1072 1093 1045 881

100 100 100 100

3.80 3.78 3.73 3.76

4.09 4.14 4.08 4.19

FSB Male

Female

Lambs Kids Lambs Kids

13 10 11 10

15.7 16.0 14.5 13.9

35.2 36.9 28.5 30.1

348 300 250 231

1078 1124 964 970

100 100 100 98

3.62 3.75 3.86 4.20

3.90 4.08 4.26 4.62

FMSB Male

Female

Lambs Kids Lambs Kids

13 10 11 10

15.7 16.2 14.6 14.0

36.3 40.2 29.8 31.0

369 343 272 243

1192 1098 1054 1006

100 98

100 97

3.71 3.20 3.87 4.14

3.97 3.49 4.24 4.54

FMFSB Male

Female

Lambs Kids Lambs Kids

13 10 11 10

15.7 16.1 14.5 13.9

36.0 38.4 29.6 30.8

364 318 269 241

1168 1040 996 941

100 100 100 98

3.80 3.27 3.70 4.03

4.07 3.58 4.07 4.44

SDa SDb SDc

2.18 2.81 2.47

3.52 4.92 4.02

42 42 45

a, b, c: Standard deviations applicable for comparisons for the lamb and kid trials or the combined analysis.

4

Table 3. Perfonnanee of Chios lambs and Damascus kids offered coneentrate mixtures with soybean meal (SB) or a soybean meal and fish meal (FMSB) as protein supplement (Experiment 2)

Daily Feed intake Feed/gain

Concen. No. of Initial Final Daily Lueerne Conc.+ mixture Sex Species animals weight weight gain Coneen. hay Coneen. hay

(kg) (kg) (g) (g) (g)

SB Male Lambs 19 19.5 40.3 365 1314 100 3.54 3.81 Kids 8 18.7 33.1 257 1138 100 4.42 4.81

Female Lambs 20 16.8 30.8 249 1062 100 4.26 4.66 Kids 8 16.4 28.6 217 968 100 4.45 4.92

FMSB Male Lambs 20 19.8 38.9 341 1229 100 3.60 3.89 Kids 8 18.8 34.8 285 1070 100 3.75 4.10

Female Lambs 20 17.0 31.2 255 1088 100 4.26 4.66 Kids 8 16.3 28.5 218 954 100 4.37 4.82

SDa 2.65 3.95 41 SDb 2.11 3.24 39 SOC 2.52 3.77 41

a, b. c: Standard deviations applicable for comparisons for the lamb and kid trials or the combine analysis.

In line with Economides (1986), lambs viewed by Kaufmann and Lupping (1982). grew significantly faster and required less In the present studies, however, in line with feed per kg body weight gain than kids. those of Schmidt et al. (1974) there were no Lambs consumed more feed than kids. How­ differences between the control and the for­ever, these results are at variance with the maldehyde-treated group. Kaufmann andsuggestion that goats exhibit a higher feed Lupping (1982) stated that when there is el-intake than other ruminants (Morand-Fehr

0.

ther no, or even a negative, effect from feed­and Sauvant, 1978). ing protected protein supplements, this may On average, protection improved weight be due to overprotection of the supplement. gain and feed conversion in the studies re-However in the present study, protection re-

Table 4. Parameter estimates (%) of DM and CP disappearance of diets fed to lambs and kids and incubated into the rumen of Damascus goats

Die ts

Item Constant SB FSB FMSB FMFSB SD

Crude a 14.2 12.9 20.1 22.0 7.58NS protein b 41.4 37.5 61.1 38.3 17.50NS

c 0.071ab 0.082ab O.04Ob 0.128a 0.053* p+ 36.2b 32.6b 45.00 44.8a 3.65* p++ 31.6b 28.6b 4l.3a 39.2a 3.05*

Dry a 35.7 33.0 34.4 26.8 7.53NS matter b 36.3 31.4 31.3 43.3 9.09NS

c 0.086 0.068 0.099 0.099 O.066NS p+ 50.2b 44.5a 52.8ab 51.2ab 2.83* p++ 46.9b 40.6a 49.5ab 46.8b 2.56*

*a,b, c: The constants of the exponential equation [p=a+b (1-e-<:l)] representing the rapidlhsoluble fraction, the fraction which will be degraded in time and the rate at whic the b fraction is degraded (Orskov and McDonald. 1979), respectively.

+ Effective degradability values at 0.05 per h outflow rate. ++ Effective degradability values at 0.08 per h outflow rate.

5

Table S. Apparent digestion coefficients of the diets

Treatments

SB FSB FMSB FMFSB SE

Feed intake (g DM/day) Concentrate 1002 1076 1126 1100 78.1 Lucerne hay 88 87 89 86 2.2

Digestibility coefficients Dry matter 0.81 0.80 0.79 0.79 0.0072 Organic matter 0.83 0.81 0.80 0.80 0.0159 Crude protein 0.77 0.76 0.76 0.75 0.0091

ME (MJ/kg feed DM) 12.2 12.0 11.2 11.8 0.385 CP intake (g/day) 214 232 245 221 16.3 CP absorbed (g/day) 165 177 186 166 ILl CP retained (g/day) 101 106 115 94 9.4

duced the digestibility of CP in the rumen, but not in the entire digestive tract.

The use of protein supplements of low degradability is expected to improve perfor­mance in growing animals, especially during the early fattening period, when there is a re­latively high rate of protein deposition and protein requirements are high (Kaufmann and Lupping, 1982). In the present studies, growth rates were similar for all protein sup­plements throughout fattening. Indeed, regar­dles of supplement, a slightly better growth rate was observed in the middle of the fatten­ing period.

Responses to slowly degradable protein sources are more evident when they are fed with high quantities of low protein content crop residues and the supplemental protein source comprises a large proportion of total dietary nitrogen (Klopfenstein, 1985). In ad­dition, Loerch (1985) postulated that low ru­men pH values, as a result of high concen­trated diets, may result in lower rumen degradation and more efficient utilization of the untreated SB. Therefore, the lack of dif­ference between the control and the treated group obtained in the present study might be ascribed to the high concentrate feeding sys­tem and the relatively adequate supplies of rumen undegradable (UDP) and degradable (RDP) protein from the control group.

A major problem encountered in some studies (Faichney and Davies, 1972; Spears et al., 1980; Mudgal and Sengar, 1981) has been a decrease in protein digestibility asso­ciated with formaldehyde treatment. In the present study, however, and in line with Rooke et al. (1982), apparent N digestibility

was not decreased significantly with formal­dehyde treatment of protein supplements. Furthermore, in this and other studies (Faichney and Davies, 1972; Spears et al., 1980; Mudgal and Sengar, 1981), apparent dry and organic matter digestibilities were not affected by treatment.

Protein source resulted in different gain responses in lambs and kids. Kids, but not lambs, on the fish meal supplemented diet grew faster and had better feed conversion efficiency than all other supplements. 'This difference might be ascribed to possible higher nitrogen requirements of kids and dif­ferences in amino acid requirements between the two species.

The concentrate mixtures with FM had greater CP effective degradability than those with SB, indicating that the FM used in the present study was of poor quality and that the SB was of lower degradability than that of FM. Furthermore, formaldehyde treat­ment of SB tended to reduce CP degradabili­ty (Hadjipanayiotou, 1992). Studies by Ngongoni et al. (1989) illustrated the varia­tion in degradability of various sources of fish meal and underlined the significance of testing the ability of different batches of fish meal to provide undegraded protein.

It is concluded that neither the protein source nor the protection of protein had a significant effect on the performance of lambs. On the other hand, FM enhanced growth rate and feed to gain ratio in kids. Such species differences might be ascribed to differences in N and amino acid require­ments of the two species. Due to the fact that

6

1

responses are obtained when levels of pro­tein are below the animal's requirements, it is essential to study further the effects of pro­tein sources under lower nitrogen levels. Fi­nally, because of its high cost per unit of CP, FM should be assessed against other nitrogen sources.

ACKNOWLEDGEMENTS

I thank Mr. A. Photiou, Mrs. Mary Kara­via, Mr. L. Hadjiparaskevas, Mr. C. Photiou and Mr. Y. Antoniou, for technical assis­tance, Mrs. Maria Theodoridou and Mr. C. Heracleous for statistical analyses and the staff of the Central Chemistry Laboratory for chemical analyses. The study was partly sup­ported by FAO/IAEA, Vienna.

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Burroughs, W., D.K. Nelson, and D.R. Mertins. 1975. Protein physiology and its application in the lactating cows. The metabolizable protein feeding standard. Journal of Animal Science 41:933-944.

Economides, S. 1986. Comparative studies of sheep and goats: Milk yield and composition and growth rate of lambs and kids. Journal ofAg­ricultural Science. Cambridge 106:477-484.

Ekern, A. 1982. Results from feeding trials and practi­cal experience concerning protein feeding of ruminants in Norway. In Protein Contribu­tion of Feedstuffs for Ruminants: Application to Feed Formulation (Miller, E.L., tH. Pike, and AJ.H. Van Es, eds) pp 87-102. Butter­worth Scientific, London.

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Faichney, GJ., and H.L. Davis. 1972. The effect of formaldehyde treatment of peanut meal in concentrate diets on the performance of calves. Australian Journal ofAgricultural Re­search 23:167-175.

Hadjipanayiotou, M. 1982. Effect of sodium bicarbo­nate and of roughage on milk yield and milk composition of goats and on rumen fermenta­

tion of sheep. Journal of Dairy Science 65:59-64.

Hadjipanayiotou, M. 1992. Effect of protein source and formaldehyde treatment on lactation per­formance of Chios ewes and Damascus goats. Small Ruminant Research 8:185-197.

Hadjipanayiotou, M., A. Koumas, E. Georghiades, and D. Hajidemetriou. 1988. Studies on deg­radation and outflow rate of protein supple­ments in the rumen of dry and lactating Chi­os ewes and Damascus goats. Animal Production 46:243-248.

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Rooke, J.A., B.W. Norton, and D.G. Armstrong. 1982. The digestion of untreated and formal­dehyde-treated soya-bean meals and estima­tion of their rumen degradabilities by differ­ent methods. Journal ofAgricultural Science, Cambridge 99:441-452.

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