The fat and protein content of the sheep milk under different conditions

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The fat and protein content of the sheep milk under different conditions Jávor A., Nábrádi A., Várszegi Z., Arnyasi M., Molnár G., Kukovics S. in Gabiña D. (ed.). Analysis and definition of the objectives in genetic improvement programmes in sheep and goats. An economic approach to increase their profitability Zaragoza : CIHEAM Options Méditerranéennes : Série A. Séminaires Méditerranéens; n. 43 2000 pages 69-74 Article available on line / Article disponible en ligne à l adresse : http://om.ciheam.org/article.php?idpdf=600469 To cite this article / Pour citer cet article Jávor A., Nábrádi A., Várszegi Z., Arnyasi M., Molnár G., Kukovics S. The fat and protein content of the sheep milk under different conditions. In : Gabiña D. (ed.). Analysis and definition of the objectives in genetic improvement programmes in sheep and goats. An economic approach to increase their profitability. Zaragoza : CIHEAM, 2000. p. 69-74 (Options Méditerranéennes : Série A. Séminaires Méditerranéens; n. 43) http://www.ciheam.org/ http://om.ciheam.org/

CIHEAM - Options Mediterraneennes 7KHIDWDQGSURWHLQFRQWHQWRIWKHVKHHSPLON XQGHUGLIIHUHQWFRQGLWLRQV $-iyru6.xnrylfv$1ieuigl=v9iuv]hjl0èuq\dvldqg*\0roqiu *Debrecen Agricultural University of Agricultural Sciences, Böszörményi str. 138, Debrecen, 4032 Hungary **Research Institute for Animal Breeding and Nutrition, Gesztenyés str. 1, Herceghalom, 2053 Hungary 6800$5<±In Hungary the Hungarian Combing Merino has been and still is the most common sheep breed. In order to increase the milk production traits, especially the milk components, several crossings were made. In an experiment lasting three years the fat, protein and dry matter contents of the milk produced by ewes belonging to different genotypes: Merino, (Merino x East-Friesian) F 1, (Merino x Langhe) F 1, (Merino x Sarda) F 1, (Merino x Pleven) F 1 and (Merino x Awassi) F 1 were studied. The test milkings of the ewes were carried out fortnightly, twice a day. From the study the following conclusions could be drawn: (i) the East-Friesian F 1 ewes produced the largest amount of fat, protein and dry matter in their milk; followed by Langhe F 1, Sarda F 1, Pleven F 1, Awassi F 1 and Merinos in the ranking; (ii) the improvement in conditions gave an increased yield of the studied traits; and (iii) the pre-selection on the basis of milk production should be made prior to the start of crossbreeding considering to increase the milk production traits..h\zrugvewe milk, protein, fat, fat free dry matter, production system. 5(680(±7HQHXU HQ PDWLqUH JUDVVH HW SURWpLQH GHV EUHELV ODLWLqUHV VRXV GLIIpUHQWHV FRQGLWLRQV$FWXHOOHPHQW FRPPH GDQV OH SDVVp OH PpULQRV SHLJQp HVW OD UDFH OD SOXV pwhqgxh HQ +RQJULH 3OXVLHXUVFURLVHPHQWVRQWpWpIDLWVDILQG DPpOLRUHUOHVFDUDFWqUHVGHODSURGXFWLRQODLWLqUHHWODFRPSRVLWLRQGX ODLWHQSDUWLFXOLHU3HQGDQWWURLVDQQpHVOHVWHQHXUVHQPDWLqUHJUDVVHHQPDWLqUHVqFKHHWHQSURWpLQHRQWpWp HQUHJLVWUpHV FKH] OHV EUHELV GHV JpQRW\SHV VXLYDQWV 0pULQRV )ULVHQ ) /DQJKH ) 6DUGD ) 3OHYHQ ) $ZDVVL) /HVWUDLWHVG HVVDLRQWpWpHIIHFWXpHVWRXWHVOHVGHX[VHPDLQHVGHX[IRLVSDUMRXU/HVFRQFOXVLRQV VXLYDQWHV SHXYHQW rwuh WLUpHV LOHV WHQHXUV OHV SOXV pohyphv HQ PDWLqUH JUDVVH HQ PDWLqUH VqFKH HW HQ SURWpLQHRQWpWpHQUHJLVWUpHVFKH]ODUDFH)ULVRQQHLLODPpOLRUDWLRQGHVFRQGLWLRQVGHSURGXFWLRQDpOHYpOHV TXDOLWpVH[DPLQpHVHWLLLcKH]ODSUpVpOHFWLRQGHODUDFHPpULQRVHQSUpFpGDQWOHVFURLVHPHQWVO DPpOLRUDWLRQ GHVFDUDFWqUHVGHSURGXFWLRQGHODLWGRLWrWUHDXVVLFRQVLGpUpH 0RWVFOpV/DLWGHPRXWRQSURWpLQHPDWLqUHJUDVVHPDWLqUHVqFKHVDQVJUDVV\VWqPHGHSURGXFWLRQ,QWURGXFWLRQ Among the products of sheep, milk production has to be emphasized because of several factors. One of these factors is our high quality wool production. The production indices in Hungary are near to the world s level, but the income from wool is only a small part of the total turnover. Meat production is already a common way of use. Milk production is the most undeveloped area, where there are many un-exploited possibilities. Especially the milk composition is the area, which could be developed rapidly. It is also important, that sheep milk production could be continuous during the year. The market of sheep milk is not overstocked yet, thus sheep milk products could be sold without stint. The fact, that the ewes are able to produce at high level for several years, has to be considered. The Hungarian "Fés V0HULQR&RPELQJ0HULQRLVWKHPRVWFRPPRQEUHHGLQ+XQJDU\KRZHYHU its milk production is low under the present keeping and breeding conditions. The improvement through selection does not require considerable financial background. Quick and high level of improvement could be expected by using milk breeds for crossbreeding. When choosing the best crossing partner it is necessary to study several breeds. 69

CIHEAM - Options Mediterraneennes The aim of the experiment was to study the production indices in the crossed/f 1 /stocks belonging to different sheep genotypes. 0DWHULDOVDQGPHWKRGV In the experiment, in addition to studying the production of the control Merino stock, 5 different breeds were used as crossing partners. The original, non-selected Merino ewes were inseminated with the sperm of Langhe, East-Friesian, Sarda, Pleven Blackhead and Awassi rams, so the studied genotypes were as follows: (i) Merino (ii) (Merino x East Friesian)F 1 /East Friesian F 1 / (iii) (Merino x Langhe) F 1 /Langhe F 1 / (iv) (Merino x Sarda) F 1 /Sarda F 1 / (v) (Merino x Pleven Blackhead) F 1 /Pleven F 1 / (vi) (Merino x Awassi) F 1 /Awassi F 1 / The experiment was carried out in two farms, and in two production systems: (i) under large scale conditions, with low production level //; and (ii) under experimental conditions, with semi-intensive production level //. The experiment was carried out through 3 years, 3 lactation periods. The ewes included in the study were milked fortnightly and milk was sampled (Kukovics HWDO 1988, 1992) two times a day. The high number of obtained data provided possibility for the in-depth analysis of the milk quality of genotypes. The analyses carried out by automatic equipment (Milkcoscan 300) on the basis of Hungarian standards were as follows: (i) butterfat-; (ii) protein-; and (iii) fat-free dry matter content. The collected data were processed in the Computer Laboratory of the Department of Animal Husbandry in Debrecen University of Agricultural Sciences, by IBM computers. Due to different weather conditions, the fodder supply of the animals was also different in each year (Jávor HW DO 1993). In addition to this, reactions of the different genotypes to the different environmental conditions were also considered in the analyses of data. 5HVXOWVDQGGLVFXVVLRQ Each genotype reacted differently under different environmental conditions (Table 1). The better keeping and feeding conditions lead to higher fat content in the case of each variety. In the case of fat level, the situation was different: in 1990, because of more favourable conditions, the fat level of the varieties was lower, than that of in 1991. Regarding butterfat yield, the biggest difference could be seen in the case of Merino and Langhe F 1 (2.5 kg), while the smallest difference were observed in the case of Sarda F 1 (1.3 kg) ewes. Regarding fat level, the biggest difference was in the case of Merino (2.2%) while the smallest was found in the East-Friesian F 1 -s (1.0%). In general, the most butterfat was yielded by the East-Friesian F 1 ewes. The most protein was also produced by East-Friesian F 1 and Langhe F 1 sheep. Bigger differences occurred in protein % under the different environmental conditions than that were in the fat content. Under the better conditions, Langhe F 1 produced the most favourable values. Under better feeding and keeping conditions its milk protein production was higher by 3.35 kg. Difference was the smallest in the case of Merino (1.8 kg) ewes. The milk protein level was relatively similar, the difference was lower than in the case of milk protein yield. Even the biggest difference did not exceed the 1% (Table 2). Regarding fat free dry matter yield, the East-Friesian F 1 was the best as well. Due to the better conditions, the production values of Langhe F 1 were considerably increased (+10 kg) which meant a 2.5 times higher value. The lowest dry matter content could be found in the milk and the biggest differences could also be found in this breed (Table 3). 70

Table 1. Fat content and yield in the milk of the studied genotypes Years Production level Genotype Number of ewes Butterfat yield (kg) Butterfat Butterfat yield in comparison Butterfat % in comparison 71 I II Langhe F 1 36 5.21 7.32 108 93 Sarda F 1 39 4.75 7.20 99 92 East-Friesian F 1 32 5.95 7.01 124 89 Pleven F 1 35 4.77 7.55 99 96 Merino 41 4.81 7.86 100 100 Langhe F 1 17 2.97 7.31 127 92 Sarda F 1 23 3.78 7.59 162 96 East-Friesian F 1 14 4.35 7.27 186 92 Pleven F 1 20 3.29 7.84 141 99 Merino 21 2.33 7.92 100 100 Langhe F 1 28 3.90 6.11 135 105 Sarda F 1 27 3.82 6.33 132 109 East-Friesian F 1 28 4.37 6.29 151 109 Pleven F 1 30 3.31 5.79 114 100 Merino 22 2.89 5.80 100 100 Langhe F 1 13 5.53 5.69 135 75 Sarda F 1 9 4.57 5.55 112 73 East-Friesian F 1 9 5.96 6.40 146 84 Pleven F 1 17 4.91 6.11 120 80 Awassi F 1 4 4.25 6.65 104 87 Merino 9 4.10 7.61 100 100 CIHEAM - Options Mediterraneennes I Langhe F 1 14 5.40 7.34 171 92 Sarda F 1 11 5.06 6.74 160 85 East-Friesian F 1 7 5.12 6.59 163 83 Pleven F 1 19 4.63 7.29 147 92 Awassi F 1 10 4.63 7.62 147 96 Merino 6 3.15 7.96 100 100

Table 2. Protein yield and level in the milk of the studied genotypes Years Production level Genotype Number of sheep Protein yield (kg) Protein Protein yield in comparison Protein % in comparison 72 I II I Langhe F 1 36 4.45 6.15 119 101 Sarda F 1 39 3.97 6.03 107 99 East-Friesian F 1 32 5.02 5.94 135 98 Pleven F 1 35 3.96 6.17 106 101 Merino 41 3.73 6.09 100 100 Langhe F 1 17 2.64 6.49 162 96 Sarda F 1 23 3.21 6.39 151 94 East-Friesian F 1 14 3.68 6.21 185 92 Pleven F 1 20 2.84 6.79 142 100 Merino 21 2.00 6.78 100 100 Langhe F 1 28 3.98 6.54 126 99 Sarda F 1 27 3.74 6.34 118 94 East-Friesian F 1 28 4.27 6.40 135 95 Pleven F 1 30 3.58 6.73 113 100 Merino 22 3.17 6.75 100 100 Langhe F 1 13 6.03 6.28 178 92 Sarda F 1 9 5.15 6.25 152 92 East-Friesian F 1 9 5.87 5.86 173 86 Pleven F 1 17 5.15 6.37 152 94 Awassi F 1 4 3.99 6.22 118 91 Merino 9 3.39 6.80 100 100 Langhe F 1 14 4.49 6.17 169 89 Sarda F 1 11 4.49 5.88 165 85 East-Friesian F 1 7 4.45 5.74 167 83 Pleven F 1 19 3.97 6.38 149 92 Awassi F 1 10 3.62 6.01 136 87 Merino 6 2.67 6.95 100 100 CIHEAM - Options Mediterraneennes

Table 3. Total fat free dry matter yield and content in the milk of the studied genotypes Years Production level Genotype Number of ewes Total dry matter yield (kg) Total dry matter Total dry matter yield in comparison Total dry matter % in comparison 73 I II Langhe F 1 36 14.02 19.40 116 98 Sarda F 1 39 12.69 19.15 105 97 East-Friesian F 1 32 15.93 18.79 131 95 Pleven F 1 35 12.42 19.49 102 99 Merino 41 12.13 19.75 100 100 Langhe F 1 17 7.99 19.52 133 96 Sarda F 1 23 9.96 19.90 166 98 East-Friesian F 1 14 11.57 19.39 193 95 Pleven F 1 20 8.52 20.28 142 100 Merino 21 5.99 20.32 100 100 Langhe F 1 28 11.48 18.59 131 101 Sarda F 1 27 11.13 18.70 127 102 East-Friesian F 1 28 12.52 18.28 143 99 Pleven F 1 30 10.02 18.49 115 100 Merino 22 8.75 18.41 100 100 Langhe F 1 13 17.70 18.24 168 90 Sarda F 1 9 14.97 18.07 142 89 East-Friesian F 1 9 19.17 18.45 173 91 Pleven F 1 17 15.23 18.59 145 92 Awassi F1 4 12.09 18.91 115 94 Merino 9 10.52 20.21 100 100 CIHEAM - Options Mediterraneennes I Langhe F1 14 14.34 19.61 179 94 Sarda F1 11 14.10 18.86 176 91 East-Friesian F1 7 14.13 17.94 176 86 Pleven F1 19 12.38 19.60 155 94 Awassi F1 10 12.06 19.88 151 96 Merino 6 8.01 20.79 100 100

CIHEAM - Options Mediterraneennes Regarding these milk components values, the smallest difference were observed in the case of Sarda F 1 ewes under different conditions. Thus for extensive production system this genotype could be suggested. The results received were similar to those ones published by Kukovics HW DO (1992, 1993). Regarding the value of milk composition, the Merino was the best variety, but the milk production of this variety was low. That was the reason why it was important to cross it with milk breeds. According the final opinion of the authors, the pre-selection of Merino stock on the bases of milk production should be made independently from the crossbreeding partner. 5HIHUHQFHV Jávor, A., Sás, Gy., Veress, L. and Kovács, Z. (1993). The effect of feeding on sheep milk production, In: Proceedings of the 5 th International Symposium on Machine Milking of Small Ruminants, Kukovics, S. (ed.), Budapest, Hungary, May 14-20, 1993. ÈOODWWHQ\pV]WpV pv 7DNDUPiQ\R]iV +XQJDULDQ-RXUQDORI$QLPDO3URGXFWLRQ Supplement 1: 541-546. Kukovics, S., Molnár, A., Mohácsi, P., 0pU *\ DQG ÈEUDKiP 0 5HODWLRQVKLS DPRQJ WKH milk components and the changes of fat, protein and lactose contents during the lactation. In: Proceedings of the 5 th International Symposium on Machine Milking of Small Ruminants, Kukovics, S. (ed.), Budapest, Hungary, May 14-20, 1993. ÈOODWWHQ\pV]WpV pv 7DNDUPiQ\R]iV +XQJDULDQ-RXUQDORI$QLPDO3URGXFWLRQ Supplement 1: 161-176..XNRYLFV60ROQiU$0RKiFVL30pU *\ÈEUDKiP0DQG6]DEDGRV$&RPSDUDWLYH valuation of crossbred milk sheep populations. 1 st. Paper: Pooled milk production results. ÈOODWWHQ\pV]WpVpV7DNDUPiQ\R]iV+XQJDULDQ-RXUQDORI$QLPDO3URGXFWLRQ 41(4): 299-309. Kukovics, S., Rákóczi, Gy., Molnár, A., Schuszter, T., Mohácsi, P. and Nagy, A. (1988). Keresztezett juhok tejtermelési MHOOHP] L elvárások és realitás (Milk production traits of crossbred ewesexpectation and reality). In: $ WHM LOOHWYH D K~VJ\DSM~ LUiQ\~ IHMOHV]WpV OHKHW VpJHL 7KH SRVVLELOLWLHV LQ WKH GHYHORSPHQW RI PLON DQG PHDWZRRO SURGXFWLRQ The Proceedings of National Sheep Breeding Symposium, Kukovics, S. (ed.), pp. 18-36. 74