Livestok Proution Siene 64 (2000) 175 181 www.elsevier.om/ lote/ livprosi Influene of vuum level, pulstion rte n pulstor rtio on mhine milking effiieny in lol Greek gots, E. Sinpis *, I. Htziminoglou, P.G. Mrnet, Z. As, A. Bolou Deprtment of Animl Proution, Fulty of Agriulture, Aristotle University, 54006 Thessloniki, Greee Equipe Assoiee ENSAR/INRA e Reherhes sur l Trite, 65Rue e St Brieu, 35042 Rennes Ceex, Frne Reeive 1 Deemer 1998; reeive in revise form 10 June 1999; epte 14 Septemer 1999 Astrt Effets of vuum level, pulstion rte n pulstor rtio on mhine milking effiieny in lol Greek gots were stuie in three seprte experiments lsting 12, 10 n 11 weeks in three ifferent yers. After wening (49 ys) ll gots were milke for 14 ys t vuum level 44 kp, 90-pulstions/min n 50:50 pulstor rtio (this 2-week intervl ws onsiere the fmiliriztion perio). In the first experiment, three groups (tretments) of gots were sujete to 70, 90 n 120 pulstions/min t milking. For the seon experiment nother three groups were milke with vuum level of 36, 44 n 52 kp. For the thir n finl experiment, three pulstor rtios; 65:35, 50:50, 35:65 were ompre in three groups. Results suggest tht fster rte (120 pulstions/ min) n higher vuum level (52 kp) erese the perentges of mhine milk (MM; from 60.6 to 55.1% for the rte n from 77.3 to 67.9% for the vuum) n totl mhine milk (TMM) while inresing the perentge of mhine strippe milk (MSM) n hn strippe milk (HSM; from 17.1 to 20.3% for the rte n from 5.7 to 10.0% for the vuum). Milking time erese s vuum levels inrese from 36 to 52 kp n s pulstor rtios inrese from 35:65 to 50:50 n 65:35. The pulstor rtio i not moify the perentge of the ove milk frtions (MM, MSM, HSM n TMM) ut i inrese the verge milking rte. Optimum onitions for mhine milking of lol Greek gots ppers to e vuum level of 36 44 kp, pulstion rte of 70 90 n pulstor rtio of 65:35. 2000 Elsevier Siene B.V. All rights reserve. Keywors: Gots; Mhine milking effiieny; Mhine prmeters; Milk frtions 1. Introution milk, MSM; hn strippe milk, HSM), resiul milk (i.e., otine y injetion of oxytoin fter Milkility is the egree to whih nimls n e milking), types of milk flow urves in ewes (with or mhine milke n is n importnt ftor in the without ejetion reflex) n milk flow rte in gots pplition of mhine milking in sheep n gots. uring mhine milking re ommonly use in smll Milk frtions (mhine milk, MM; mhine strippe ruminnts to evlute this milkility (Lussiere, ` 1988; Le Du, 1989). It is generlly epte tht *Corresponing uthor. Tel.: 1 30-31-471-256; fx: 1 30-31- gots re esy to milk (Le Du, 1989), ut some of 473-275. them (those with higher proportion of mhine E-mil ress: sinpis@gro.uth.gr (E. Sinpis) strippe milk) re generlly hrer to milk (Bouillon 0301-6226/ 00/ $ see front mtter 2000 Elsevier Siene B.V. All rights reserve. PII: S0301-6226(99)00151-7
176 E. Sinpis et l. / Livestok Proution Siene 64 (2000) 175 181 n Rioreu, 1970). Sinpis et l. (1993) foun ifferent prity, 1,2,3 1 lttion (2,3,4 1 yers tht, in lol Greek gots, the perentge of mhine ol), were rnomize in eh experiment. Thus, milk ws reltively lower thn for other rees, there were not the sme nimls uring the 3 yers. wheres the perentge of strippe milk (y mhine Animls were milke twie ily (08:30 n 17:30 n y hn) ws higher, suggesting poor milkility h) in 1 3 24 sie y sie milking prlor, with 12 for these gots. In gots with low milk yiel (lol milking units, n low milk line n ir pipeline. Greek gots), the est milking performnes hve to During ontrol perio (14 ys) of fmilirize hieve minly through mximizing the mhine tion n equilirtion of the lots on the sis of milk milk frtion n milking rte while minimizing the proution, ge n prity, the gots were milke t hn strippe milk frtion. The reution or eri- 44-kP vuum level, t 90 pulstions/ min n tion of lorious hn stripping is prerequisite using 50:50 pulstor rtio. After this ontrol perio, for the glol effiieny of iry ree. the following tretments were pplie: Different opertions n e pplie uring mhine milking of smll ruminnts in orer to simplify in experiment 1, pulstion rtes of 70, 90 n 120 the milking proeure n to extrt the milk present pulstions/ min in 12, 11 n 12 gots, respetivein the uer ompletely n rpily (Lussiere, ` ly, were use; 1969; Rioreu, 1974; Le Mens et l., 1979). It is in experiment 2, vuum levels of 36, 44 n 52 well known tht the volume of mhine milk n kp, in 15, 16 n 15 gots, respetively, were hn strippe milk n e ffete y mehnil use; ftors (i.e., vuum level, pulstion rte n pul- in experiment 3, pulstor rtios of 65:35, 50:50 stor rtio) n y the imeter of the liners (Le Du, n 35:65, in 19, 18 n 19 gots, respetively, 1989; Thoms et l., 1991). Aitionlly, milking were use. rte in gots ( highly inheritle trit, Rioreu et l., 1989) n e inrese y higher vuum levels (Lu et l., 1991), y higher pulstor rtios (Riormhine milking prmeters i not iffer from Simultneously, for eh experiment the other two eu n Lussiere, ` 1970; Le Du, 1989; Lu et l., 1991) n to lesser extent y fster pulstion rtes those of the ontrol perio. (Lu et l., 1991). Before improvement of milkility, During the first experiment the tetup use n e hieve through geneti seletion, we hve onsiste of trnsprent plsti shell n silion to ientify the est proeures involve in mhine liner espeilly esigne for gots (20-mm mouth- milking in orer to relise the full potentil of our piee ore n 21.5 mm i.. 75 mm own from the lol Greek gots. mouthpiee, Fullwoo, no. 20236). For the other two The im of this stuy ws to etermine the yers, euse of the high perentge of HSM optimum vuum level, pulstion rte n pulstor oserve, liners, espeilly esigne for sheep, with rtio y mesuring vrious milk frtions n qunmouthpiee to 75 mm own in the rrel (Fullwoo, the sme reue imeter of 19.5 mm from the tifying milk emission hrteristis in lol Greek gots. no. 20119) were use. In eh experiment every Wenesy, milk frtions t morning n fternoon milking were re- 2. Mterils n methos ore s follows (Lussiere, ` 1969): The effets of vuum level, pulstion rte n pulstor rtio on mhine milking effiieny in lol Greek gots were investigte in three seprte experiments t the Thessloniki University Frm, in three ifferent yers (i.e., one experiment per yer), over 12-, 10- n 11-week perio, following the wening t 4964 ys fter kiing. Gots of () mhine milk (MM); () mhine strippe milk (MSM); () hn strippe milk (HSM); in this wy, it ws possile to lulte for eh got; () totl mhine milk (TMM 5 MM 1 MSM); n (e) milk yiel (MY 5 TMM 1 HSM).
E. Sinpis et l. / Livestok Proution Siene 64 (2000) 175 181 177 Eh frtion ws expresse s perentge of milk Bouillon et l. (1984) oserve tht n inrese from yiel. 90 to 120 pulstions/ min inrese milk proution In the seon n thir experiment, the milk flow y only 2% in Frenh Alpine n Snen gots. Lu urve of eh got ws rwn y using pper tpe et l. (1991) lso reporte tht, in Alpine gots, the tthe to the milk reoring jrs. The milk yiel optiml pulstion rte ppere to e 90 pulstions/ level ws reore every 4 s. The milk emission min. A rnge of pulstion rtes from 70 to 100 kinetis were mesure uring three suessive pulstions/ min hs een propose y Le Du (1989). morning milkings of the seon, fifth n eighth In Norwegin got hers Rønningen n Luner weeks of the experimentl perios. The verge (1999) reporte tht the optimum pulstion rte milking rte (ml/s) ws lulte s: mhine milk rnge from 60 to 90 pulstions/min. yiel/ milking time. Consiering ll this t n our results, where the Dt were nlyze seprtely for eh experi- MM% ws lower with 120 pulstions/ min, we n ment. All the prmeters mesure were ompre onlue tht the optiml pulstion rte for ll rees y ANOVA using the SAS Generl Liner Moel of got, espeilly the lol Greek ree, rnges proeure (SAS, 1994). The weeks were trete s from 70 to 90 pulstions/ min. ifferent lok. Multiple men omprisons were The perentge of mhine milk for the lol me using Dunn s multiple rnge test, to lssify Greek gots use in this experiment remin lower the effet of the ifferent tretments (pulstion rte, thn tht of other gots rees milke t 60 to 90 vuum level n pulstor rtio). pulstions/ min. This perentge ws: 87.4% in Snen (Bouillon n Rioreu, 1970), 89.5% in Alpine Chmoisee n Poitevine (Rioreu n 3. Results n isussion Lussiere, 1970), 86.9% in Alpine Chmoisee (Le Mens et l., 1979), 88.1% in Alpine Chmoisee n In the first experiment, the inrese of pulstion Snen (Le Mens n Disset, 1984), 91.2 96.3% in rte from 90 to 120 pulstions/ min erese the Swiss Snen (Brukmier et l., 1994) n 81.5% perentge of mhine milk (P, 0.01) n inrese in Murino Grnin (Peris et l., 1996). This (P, 0.05) the perentge of mhine strippe n suggests either poor retivity to stimultion y the hn strippe milk (Tle 1). Although the per- pulstion rte (less oxytoin ishrge or less senentge of mhine strippe milk inrese signifi- siility of mmmry gln?) or morphologil ntly with 120 pulstions/ min, the totl mhine negtive prmeter (tet hrteristis, uer shpe milk (TMM%) remins signifintly lower thn with or perentge of isternl volume?) tht nee to e 90 or 70 pulstions/ min (79.7, 82.1 n 82.9%, erite y geneti seletion in lol Greek gots. respetively). It shoul e note, however, tht the In the seon experiment the inrese of the verge ily milk yiel ws similr in ll groups. vuum level from 36 to 52 kp inrese (P, 0.01) Tle 1 Effet of pulstion rte on mhine milking effiieny in lol Greek gots Pulstion rte (men6s.d.) 70 90 120 Milk yiel (ml/ y) 784.06441.4 803.76374.8 758.96338.2 NS Milk frtions (y): Mhine milk (MM) 60.6 634.1 61.0 622.7 55.1 620.0 ** Mhine strippe milk (MSM) 22.3 612.1 21.1 613.1 24.6 615.2 * Hn strippe milk (HSM) 17.1 612.4 17.9 613.1 20.3 612.1 * Totl mhine milk (TMM) 82.9 612.4 82.1 613.1 79.7 612.1 *, Mens in row with ifferent supersripts (,) iffer signifintly (*P, 0.05; **P, 0.01). Perent of milk yiel. Signifine
178 E. Sinpis et l. / Livestok Proution Siene 64 (2000) 175 181 Tle 2 Effet of vuum level on mhine milking effiieny in lol Greek gots Vuum level (kp) 36 44 52 Men6s.. Men6s.. Men6s.. Milk yiel (ml/ y) 776.86392.2 760.36413.9 787.46474.4 NS Milk frtions (y): Mhine milk (MM) 77.3 616.8 74.5 612.7 67.9 616.8 ** Mhine strippe milk (MSM) 17.0 612.1 19.5 69.8 22.1 613.5 ** Hn strippe milk (HSM) 5.7 67.9 6.3 65.7 10.0 67.8 ** Totl mhine milk (TMM) 94.3 67.9 94.0 65.7 90.0 67.8 ** e Milk emission : Mhine milk (ml) 396.56160.1 362.46140.5 334.16139.7 NS Averge milking rte (ml/ s) 7.261.8 7.762.4 8.162.2 NS Milking time (s) 53.4 625.2 43.6 621.3 38.1 612.8 *,, Mens in row with ifferent supersripts iffer signifintly (*P, 0.05; **P, 0.01). Perent of milk yiel. e Reore only t morning milking (see Setion 2). Signifine the perentges of mhine strippe n hn strip- my inrese the risk of mstitis (Le Du, 1989). In pe milk (MSM n HSM; Tle 2) while ily milk the sme lol ree of gots, Sinpis n Vlhos yiel ws not ffete uring the sme perio. (1999) foun tht inresing the vuum level from Results from Tle 2 lso show tht the perentge 36 to 44 n 52 kp signifintly inrese (P, of MM n the TMM erese n the MSM n 0.001) the somti ell ounts (SCC) in the frtion HSM inrese s the vuum level rehe 52 kp. of totl mhine milk (TMM) without the pper- It ppers tht the milking time (Tle 2) erese ne of linil mstitis. mrkely (15.3 s or 28.7%) t 52 kp ompre to Lu et l. (1991) preferre to milk Alpine gots t 36 kp. However, the milk flow rte (ml/ s) of lol 52 kp euse of its positive effet on milking Greek gots ws not ffete y the vuum level performne, ut t the expense of inrese SCC. euse s the milking time erese the volume of For lol Greek gots, the time spent milking is not mhine milk lso erese with vuum level the most importnt ftor. The optimum rnge of inrese. vuum level shoul e etween 36 n 44 kp to Bouillon n Rioreu (1981) reporte similr inrese the frtion MM% n reue HSM%, finings in tht milk flow rte inrese in Frenh without signifint moifition of the milk flow gots (Chmoises, Snen n roises) s vuum rte. This result is in greement with n verge level inrese from 38 to 51 kp. Lu et l. (1991) vuum level of 46.5 kp use in Norwy (Rønninglso foun tht the milking time erese sig- en n Luner, 1999). nifintly n verge n mximum milking flow In the thir experiment (Tle 3) the erese of rte inrese signifintly s vuum level inrese pulstor rtio from 65:35 to 50:50 n 35:65 i not from 38 to 52 kp. These results onfirm tht high ffet the TMM% (94.1, 93.8 n 94.8, respetively) vuum level is neee to open the tet sphinter in nor the HSM% (6.0, 6.2 n 5.2, respetively), gots. This point hs een previously stuie y Le lthough Rioreu n Lussiere ` (1970) foun Du n Benmeerel (1984) in Frenh Snen gots, tht the moifition of the pulstor rtio from 75:25 in whih minimum vuum of 34.6 kp, without to 50:50 inreses the volume of MSM t the pulstion, ws require t the eginning of lttion, morning (30%) n evening (24%) milking. The while 44 50 kp ws often neee for 10 15% of verge milking time ws higher (P, 0.05) in the the gots. It is generlly mitte tht n inrese in group with pulstor rtio 35:65 n the verge vuum level uses erese in milking time, ut milking flow rte (ml/s) inrese from 7.3 to 10.1
E. Sinpis et l. / Livestok Proution Siene 64 (2000) 175 181 179 Tle 3 Effet of pulstor rtio on mhine milking effiieny in lol Greek gots Pulstor rtio (men6s.d.) 35:65 50:50 65:35 Milk yiel (ml/ y) 819.26325.9 830.56387.3 884.16307.3 NS Milk frtions (y): Mhine milk (MM) 75.0 613.7 72.0 615.1 75.1 613.1 * Mhine strippe milk (MSM) 19.2611.2 21.8612.1 19.0611.4 NS Hn strippe milk (HSM) 5.864.5 6.265.8 6.065.4 NS Totl mhine milk (TMM) 94.264.5 93.865.8 94.165.4 NS Milk emission : Mhine milk yiel (ml) 414.7 6192.6 417.9 6270.5 469.3 6185.0 * Averge milking rte (ml/ s) 7.3 61.9 8.6 62.5 10.1 62.8 * Milking time (s) 58.5 628.6 45.0 621.7 45.6 613.1 *, Mens in row with ifferent supersripts iffer signifintly (*P, 0.05). Perent of milk yiel. Reore only t morning milking (see Setion 2). Signifine ml/ s (n inrese of 38.7%) s the pulstor rtio gots. Perhps this is euse our lol ree hs inrese from 35:65 to 65:35 (P, 0.05). The sme more resistnt sphinter whih requires more time to teneny hs een reporte y Rioreu n Lus- open. siere ` (1970) in Alpine Chmoisees n Poitevine In lol Greek gots the esirle pulstor rtio gots, y Bouillon n Rioreu (1981) in Frenh ppers to e etween 65:35 n 50:50. This result gots (Chmoises, Snen n roises) n y Lu et grees with those of 50:50 70:30 propose y Le Du l. (1991) in Alpine gots. In iry ows Rosen et l. (1989) for the Frenh Alpine n Snen gots n (1983) foun tht verge milking rte inrese n with those of 60:40 foun y Lu et l. (1991) for milking time erese with wier pulstor rtios. Alpine gots n with the reommentions of Thus, in gots, just s in iry ewes (Lussiere ` et 60:40 65:35 for the Norwegin gots hers (Rønnl., 1974) n in iry ows (Lussiere ` n Rih- ingen n Luner, 1999). r, 1965), the pulstor rtio is one of the min To onlue, the results of our stuy showe tht ftors whih etermines the milk flow rte, with n the optimum onitions for mhine milking lol inrese of 23% s the pulstor rtio inrese from Greek gots is vuum level of 36 44 kp, 50:50 to 75:25 (Le Du, 1989). pulstor rtio of 65:35 n pulstion rte of 70 90 The men vlue of milk flow rte (10.1 ml/s) in pulstions/min. In spite of ovious ifferenes in our group 65:35 ws higher thn tht of 8.23 ml/ s got ree, our results gree with the mhine reporte y Peris et l. (1996) in Murino- prmeters lssilly use in 15 ountries (vuum Grnin iry gots milke in the fternoon t level etween 36 n 45 kp, pulstor rtio etween 64:36 pulstor rtio, ut it ws lower thn tht of 50:50 n 60:40 n the pulstion rte etween 70 16.1 ml/s in Alpine gots (Lu et l., 1991) n tht n 90 pulstions/min) (Billon et l., 1999). of 14 ml/s, reporte y Brukmier et l. (1994) in A finl point must lso e onsiere. When we Swiss Snen gots, milke t similr pulstor rtio exmine the three experimentl perios when the of 60:40. The other two mhine prmeters were: gots were milke with the sme mhine prmeters for Murino-Grnin 42 kp n 90 pulstions/ (44 kp, 90 pulstions/min n 50/50 rtio, i.e., the min n for Alpine n Swiss Snen gots 90 seon olumn of t in Tles 1 3), it is ovious pulstions/min n vuum level of 52 n 48 kp, tht the HSM% in experiment 1 ws higher (17.9%) respetively. Finlly, the urtion of sution phse in omprison with the other two experiments, where uner the tet sphinter seems to e more importnt the HSM% ws lower (6.3 n 6.2%, respetively). thn the vuum level for the milking effiieny in This ifferene oul e ttriute to the ifferent
180 E. Sinpis et l. / Livestok Proution Siene 64 (2000) 175 181 type of liners use etween the first yer n the ftors influening the milking ility of ewes n the orgni- ztion of milking. Livest. Pro. Si. 18, 253 274. other 2 yers sine the ge n prity of gots were Lussiere, ` J., Rihr, P., 1965. L trite menique: Aspets the sme mong the 3 yers (see Setion 2). It oul ntomiques, physiologiques et tehnologiques. Mise u point e ssume tht the smller imeter of liners is one iliogrphique. Ann. Zooteh. 14, 63 126. of the essentil ftors whih positively influene Lussiere, ` J., Le Du, J., Douire, M., Comu, J.F., 1974. Effets (lower HSM%) the milking effiieny of lol gots. e l vitesse et u rpport e pulstion sur les rteristiques e trite ` l mhine es reis Prelpes u Su. Ann. It ws oserve tht the tets penetrte too eeply Zooteh. 23, 459 480. insie the liners. Tht le to effiieny of the Le Du, J., 1989. 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E. Sinpis et l. / Livestok Proution Siene 64 (2000) 175 181 181 Brillet, F., Zervs, N.P. (Es.), Pro. 6th Interntionl Sym- Mhine Milking of Smll Ruminnts, My, 14 20, 1993, posium on the Milking of Smll Ruminnts, Sept. 26 Ot. 1, Bupest, Hungry, pp. 457 467, Hungrin Journl of Ani- 1998, Athens, Greee, Milking n Milk Proution of Diry ml Proution. Sheep n Gots, pp. 513 518, EAAP pulition no. 95. Thoms, C.V., Fore, D.K., Bremel, D.H., Strsser, S., 1991. Sinpis, E., Lussiere, ` J., Htziminoglou, J., 1993. L ptitue ` Effets of pulstion rtio, pulstion rte n tetup liner l trite menique es hevres ` e l re lole greque. In: esign on milking rte n milk proution. J. Diry Si. 74, Kukovis, S. (E.), Pro. 5th Interntionl Symposium in 1243 1249.