Maciej Murawski and Urszula Kaczor ©
University of Agriculture, Department of Sheep and Goats Breeding, Krakow,
Poland
IMPROVEMENT OF LAMBS PRODUCTION THROUGH EWE'S ESTROUS CYCLE SYNCHRONIZATION IN THE THREE FARMS OF BESKID NISKI MOUNTAIN
Abstract
Estrous synchronization was induced in 450 ewes totally in three flocks consistoing of 125, 150 and 175 ewes in each farm, respectively. After estrous synchronization the highest prolificacy was observed in the third flock 157% and 119% and 147% in the first and the second flock. After estrous synchronization the prolificacy was statistically different (p<0.05) only in the second flock but in the other flocks were higher than natural prolificacy of about 14 and 10% in the first and in the third flock, respectively. The highest average of body condition score 2.5 was observed in the third flock but 2.25 and 2.4 scores were noted in the first and in the second flock. The data indicates that the estrous synchronization is a very effective method for increasing the meat lambs production especially in flocks with low prolificacy.
Key words: estrous synchronization, lambs, body condition score
Introduction. Sheep husbandry in Poland is a typically seasonal brunch of domestic animal production. Seasonal production causes some problem for sheep industry with keeping constant supply of its products to the market. Consumers expect to have possibility to buy lamb around the whole year but traditional husbandry of sheep makes it possible to fulfill markets only during the summer and autumn seasons. Because of that, sheep husbandry requires new solutions for changing strategy of production and improving reproduction methods and managing systems. Some of those methods include hormonal treatment for estrous synchronization which increases prolificacy and gives possibility to produce lambs in any season of the year.
Polish mountain sheep are known from its low prolificacy averaging 130%, low ability of their lambs for getting the body weight higher than 30 kg and very good ability to survive in harsh environments. The possibility of Polish Mountain Sheep to increase lambs production could be achieve by exogenous hormones estrous synchronization during the breeding and out of breeding season.
The aim of the article. The objective of this study was to investigate the possibility to increase the prolificacy in Polish Mountain Sheep by exogenous hormones treatment to synchronize the estrous cycle.
Materials and Methods. Data were collected from 450 Polish Mountain sheep breed from 1,5-7 years old in three flocks in Beskid Niski Mountain. There
© Maciej Murawski and Urszula Kaczor
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were 125, 150 and 175 ewes in the first, second and third farm, respectively. At the beginning of May to the end of the October on each farm ewes were reared on the pastures. From November to the end of April, ewes were kept in sheepfolds and they were fed by grass silage (2-3kg/ewe/day) and grass hay (1-1,5kg/ewe/day). All the time sheep had free access to the water.
Estrous synchronization was curried out at the beginning of reproduction season (the end of August). For estrous synchronization Chrono-gest® method was used. Sponges impregnated with cronolone (40 mg) were inserted into vagina of each ewe and after 14 days they were removed and PMSG was injected in the dose of 500 I.U. Ewes were mated in 48 and 60 hours after sponge withdrawal. Body condition scoring (based on a scale from 1 to 5) was performed for each ewe one month before estrous synchronization. Results of investigation were analyzed by the SAS statistical package.
Results of researches. Data collected on three farms shows that the highest prolificacy of 157% after estrous synchronization was noticed in the third farm where non-synchronized prolificacy was also the highest 138%. The first and the second farms were characterized by natural prolificacy of about 105 and 115% and after estrous synchronization 119 and 147%, respectively were observed (Fig.1). Statistical difference (p<0.05) between natural and stimulated prolificacy by exogenous hormones was noticed only in the second flock.
180 i
Flock
A,B Values with different superscripts are statistically different (p<0,001)
Fig.1. Efficiency of estrous synchronization of Polish Mountain Sheep in three flocks which differ in natural prolificacy.
Tecer et al. (2007), Zeleke el al. (2005), Simonetti et al. (2002), Crosby et al. (1991). reported the similar efficiency in estrous synchronization using the exogenous hormones in ewes.
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After estrous synchronization we noticed 110, 147 and 173 ewes lambed and their prolificacy in the first, the second and the third farm were 119, 147 and 157%, respectively.
The prolificacy in those three flocks was related to the ewes' body condition score. The highest average score of 2.5 one month before estrous synchronization was noticed in the third flock of sheep, 2.4 and 2.25 were observed in the second and in the first, respectively. Distribution of the ewes scoring body condition in each flock is shown on the Fig. 2.
60
50
40
I
® 30
B 20
w 10
U
□ Flock I
□ Flock II
□ Flock II
0-1,5 1,51-2 2,01-2,5 2,51-3 Body condition score
3,01-3,5
0
Fig. 2. Distribution of scoring body condition of Polish Mountain ewes on the three farms .
The data correspond with observation by Khan et al. (1992) and Russel (1991) who found that body condition scoring affects litter size and lambs birth weight. However, Al-Sabbagh et al. (1995) noticed that ewes with 3.5 body condition score weaned fewer lambs than ewes with 3.0 body condition score.
Conclusions. This observation indicates that ewe's estrous synchronization is one of the very effective method for increasing meat lambs production especially in flocks with natural low prolificacy. Based on data got from those three farms, we conclude that ewes with a higher body condition scoring are characterized by a higher prolificacy.
Research was supported by State Committee for Scientific Research as a Research Project KBN 2P06Z 04729
Reference
1. M. Zeleke, J. P. C. Greyling, L. M. J. Schwalbach, T. Muller and J. A. Erasmus. Effect of progestagen and PMSG on oestrous synchronization and fertility in Dorper ewes during the transition period. Small Ruminant Research vol. 56; 1-3:47-54,2005
2. Crosby, T.F.; Boland, M.P.; Gordon, I. Effect of progestagen treatments on the incidence of oestrus and pregnancy rates in ewes. Animal Reproduction Science, vol. 24:109-118, 1991.
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3. Simonetti L., Ramos G., Gardon J.C. Effect of estrus synchronization and artificial insemination on reproductive performance of Merino sheep. Brazilian Journal of Veterinary Research and Animal Science vol.39; 3:147-154, 2002
4. Khan K.,Meyer H.H. and Thompson J.M. Effect of prelambing supplementation and ewe body condition score on lamb survival and total weight of lamb weaned. Proceedings Western Section American society of Animal Science 43: 175, 1992
5. Russel A. Body condition scoring of sheep In: E. Boden (Ed.) sheep and Goat Practice. p.3 Billiere Tindall, Philadelphia. 1991
6. Al-Sabbagh T. A., Swanson L. V., and Thompson J. M. The effect of ewe body condition at lambing on colostral immunoglobulin G. Journal of Animal Science 73:2860-2864, 1995.
Summary
Polish Mountain sheep are known from a low prolificacy average of 130%. Low possibility of Polish Mountain Sheep to get high lambs production could be increased by exogenous hormones estrous synchronization. Estrous synchronization was induced in 450 ewes originated from three flocks (125, 150 and 175 ewes were in each farm, respectively). After estrous synchronization, the highest prolificacy was observed in the third flock of 157% and 119 and 147% in the first and the second flock. The prolificacy after estrous synchronization was statistically different (p<0.05) only in the second flock but in other flocks were also higher than natural prolificacy of 14 and 10% in the first and in the third flock respectively. The highest average of body condition score 2.5 was observed in the third flock but 2.25 and 2.4 were noted in the first and in the second flock. Those data indicate that estrous synchronization is a very effective method for increasing meat lambs production especially in flocks with low natural prolificacy and ewes with higher body condition scoring are characterized by higher prolificacy.
Резюме
Польсьт ripcbKi sisц eidoMi своею низькою середньою величиною nлoдючocтi (130%). Низька можливкть польськог Прськог Ывщ давати високу кыьюсть ягнят могла би бути збыьшена екзогенною гормональною синхротзащею охоти. Синхротзащя охоти тдукувалася у 450 овець, що походять з трьох стад (125, 150 i 175 овець знаходилося на кожтй фeрмi, eiдnoeiднo). Шсля синхротзацп охоти, найвища плодючкть спостеркалася в третьому cтадi 157% i 119 i 147% в першому i другому стадох. Плодючкть тсля синхротзацп охоти статистично eiдрiзнялаcя (p<0.05) тыьки в другому cтадi, але в тших стададах були також вищим, тж природна плодючкть 14 i 10% в першому i третьому стадах eiдпoeiднo. Найвища середня величина показника стану тыа (2.5) cпocтeрiгалаcя в третьому cтадi, але 2.25 i 2.4 були eiдзначeнi в першому i в другому cтадi. Щ дат вказують, що синхротзащя охоти це дуже дiеeий метод для збыьшення виходу м'яса овець, особливо в стадах з низькою природною плодючктю i eieцeматoк з вищим показником стану тыа що характеризуеться вищою плодючктю.
Стаття надшшла до редакци 20.09.2008
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