scholarly journals Effect of milking vacuum level and overmilking on cows’ teat characteristics

2011 ◽  
Vol 59 (5) ◽  
pp. 193-202 ◽  
Author(s):  
M. Pařilová ◽  
L. Stádník ◽  
A. Ježková ◽  
L. Štolc
Keyword(s):  
Wall Thickness ◽  
Treatment Effects ◽  
Vacuum Level ◽  
Milk Flow ◽  
Before And After ◽  
Teat Canal ◽  
Test Treatment

The influence of milking vacuum and milk flow level (resp. detachment level) on cows’ teat characteristics were studied in four experiments. The MIXED procedure was used to test treatment effects on the level of teat length, teat thickness at the base and half-way between the teat end and the base of udder, teat canal length, teat end width, teat wall thickness, teat cistern width after milking and on differences between these teat characteristics measured before and after milking. A total of 51 cows were included in all experiments. All the cows had clinically healthy udders. Some cows were involved in two or more experiments. Finally, 330 teat measurements of 165 cows were taken and statistically processed. Vacuum and milking with or without overmilking significantly (P < 0.05-0.001) influence monitored parameters. Milking vacuum has an influence on two of three measured external teat parameters: teat diameter measured at the base of the teat and half-way between the udder base and the teat tip. Change in teat length measured before and immediately after milking was higher when higher vacuum of 45 kPa was used. Detachment level also has an influence on teat proportions. Overmilked teats were longer and narrower compared to non-overmilked teats. Interaction between milking vacuum and detachment level influences external teat parameters as well.

scholarly journals Vacuum level for opening the teat sphincter and the change in the teat end wall thickness in response to the machine milking of indigenous Greek goats

2008 ◽  
Vol 53 (No. 3) ◽  
pp. 112-118 ◽  
Author(s):  
B. Skapetas ◽  
J. Katanos ◽  
V. Laga ◽  
Ε. Sinapis ◽  
I. Hatziminaoglou
Keyword(s):  
Wall Thickness ◽  
Experimental Period ◽  
Vacuum Level ◽  
Machine Milking ◽  
Stage Of Lactation ◽  
Lactation Stage ◽  
Before And After ◽  
Milking Machine ◽  
End Wall ◽  
Teat Canal

The aim of this paper was to study some of the teat characteristics involved in the milking ability of indigenous Greek goats such as the vacuum level of the milking machine that is required for the opening of the teat canal sphincter and the changes in the teat end wall thickness induced by milking. Thirty-six dams (12 of the first, 12 of the second and 12 of the third and subsequent lactations) were used after weaning (60 ± 5 days). Dams were milked twice a day (8:00 and 18:00 h) for 12 weeks in a milking parlour 1 × 12 side by side of Casse type with 6 milking units and a low milk line and air pipeline. The main functional characteristics of milking machine were: vacuum level 44 kPa, pulsation rate 90 pulsations/min and pulsation ratio 50:50. Every 14 days, during morning and evening milking the vacuum level that was required for the opening of the teat sphincter (VOTS) was measured. The measurement of teat end wall thickness (TEWT) was performed before and after milking. The results of this study showed that during the experimental period the mean VOTS was 23.57 ± 0.36 kPa and decreased significantly as the stage of lactation progressed (<I>P</I>< 0.001). The post-milking TEWT was 3.55% higher in comparison with that before milking (<I>P</I> < 0.01). A continuous and significant decrease in teat thickness was observed during the lactation stage (<I>P</I> < 0.001), which suggests a reaction to intramammary pressure and milk quantity in the udder. The TEWT was affected significantly by the parity (<I>P</I> < 0.01). A positive correlation was found between VOTS and TEWT before and after milking (0.4 and 0.36, respectively). It could be said that a lower vacuum level is required for the opening of the teat sphincter of the udder in goats of the indigenous Greek breed. The thicker teat end wall and more resistant sphincter could be less favourable in the machine milking of goats.

scholarly journals Teat anatomy affects requirements for udder preparation in Mediterranean buffaloes

2010 ◽  
Vol 77 (4) ◽  
pp. 468-473 ◽  
Author(s):  
Sarah Ambord ◽  
Michael H Stoffel ◽  
Rupert M Bruckmaier
Keyword(s):  
Cross Section ◽  
The Other ◽  
Longitudinal Cross Section ◽  
Additional Experiment ◽  
Milk Ejection ◽  
Machine Milking ◽  
Milk Flow ◽  
Before And After ◽  
Teat Canal ◽  
Anatomical Parameters

The present study was conducted to assess the interrelation between teat anatomy and machine milking in dairy buffaloes raised in Switzerland. A 3-min pre-stimulation induced milk ejection before cluster attachment in most cases and caused an optimal milk removal during machine milking. In an additional experiment, longitudinal cross-section ultrasound was obtained before and after a 3-min pre-stimulation. Teat wall thickness, teat diameter, cisternal diameter and teat canal length were evaluated. It was observed that 3-min pre-stimulation dramatically reduced teat canal length whereas all the other anatomical parameters remained unchanged. The vacuum needed to open the teat canal was also measured before and after a 3-min pre-stimulation by using a special teat cup with only the mouthpiece of the liner remaining on the top of the teat cup (no liner, no pulsation). Without pre-stimulation but after wetting the teat canal by stripping one squirt of milk out of the teat, no milk could be withdrawn with a vacuum up to 39 kPa. However, after pre-stimulation, milk flow occurred in all buffaloes at a vacuum between 16 and 38 kPa. In the last experiment, the teat tissue was examined in slaughtered buffaloes and compared with teat tissue of cows. No difference was noted in histological sections and teat canal length was similar in cows and buffaloes. Proximal to the teat canal, the teat did not pass into an open cistern but the lumen was collapsed. In conclusion, buffaloes need to be well pre-stimulated because the tissue above the teat canal provides additional teat closure before milk ejection. Therefore, milk can only be obtained after pre-stimulation.

scholarly journals Post-exercise pulsatility index indicates treatment effects in peripheral arterial occlusive disease (PAOD)

2021 ◽  
Author(s):  
Andrej Udelnow ◽  
Maria Hawemann ◽  
Ivo Buschmann ◽  
Frank Meyer ◽  
Zuhir Halloul
Keyword(s):  
Repeated Measures ◽  
Pulsatility Index ◽  
Treatment Effects ◽  
Resistance Index ◽  
Peak Systolic Velocity ◽  
Arterial Tree ◽  
Post Exercise ◽  
Diastolic Velocity ◽  
Before And After ◽  
Healthy Persons

Summary Background Hypothesis: Post-exercise measurements better discriminate PAOD-patients from healthy persons and they more sensitively detect hemodynamic improvements after treatment procedures than resting measurements. Methods A total of 19 healthy volunteers and 23 consecutive PAOD-patients underwent measurements of peak systolic velocity (PSV), end-diastolic velocity (EDV), minimal diastolic velocity (MDV), time-averaged maximum velocities (TAMAX), resistance index (RI) and pulsatility index (PI) before and after a standard exercise test (at 1, 2, 3, 4 and 5 min) before and after treatment (incl. epidemiological data, PAOD risk factors and comorbidities). Results In resting values, healthy persons and PAOD-patients did not differ significantly in any of the hemodynamic parameters. PSV increased after treatment in PAOD-patients by 5 cm/s (paired t‑test, p: 0.025); however, when the amplitude of autoregulatory changes related to the resting values were calculated, PAOD-patients showed clearly less hemodynamic changes after exercise than healthy persons (p: 0.04; 0.002; <0.001 for PSV, TAMAX and PI, resp.). The time course after exercise was compared by repeated measures of ANOVA. Healthy persons differed significantly in PI, RI and PSV from PAOD patients before and after treatment (p<0.001 each). The PAOD-patients revealed a significantly improved PI after treatment (p: 0.042). The only factor contributing significantly to PI independently from grouping was direct arterial vascularization as compared to discontinuous effects by an obstructed arterial tree. Conclusion Healthy persons cannot be well differentiated from PAOD-patients solely by hemodynamics at rest but by characteristic changes after standard exercise. Treatment effects are reflected by higher PI-values after exercise.

Responses of the bovine teat to machine milking: measurement of changes in thickness of the teat apex

1988 ◽  
Vol 55 (3) ◽  
pp. 331-338 ◽  
Author(s):  
Jörn Hamann ◽  
Graeme A. Mein
Keyword(s):  
Positive Pressure ◽  
Vacuum Level ◽  
Machine Milking ◽  
Before And After ◽  
The Mean ◽  
High Degree

SummaryChanges in the teat apex before and after different milking treatments were measured with a spring-loaded caliper device known as a cutimeter which could detect changes in thickness of the tissues of the teat end, presumably due to congestion and/or oedema, with a high degree of accuracy (± 2%) and repeatability (r = 0·99). Teat end thickness increased with increasing vacuum level. The mean increase immediately after milking with a conventional cluster was 2% for 24 teats milked at 30 kPa, 8% at 50 kPa and 21% at 70 kPa. At these vacuum levels, the mean increases for the same teats milked with an unconventional (PKME) teatcup were 10, 18 and 25% respectively. Cyclic application of 35 kPa positive pressure to the pulsation chamber of a conventional teatcup operating at 50 kPa reduced teat end thickness by 8% compared with the mean premilking value. Although most teats returned to within ± 2% of their premilking thickness values by 1 h after milking, differences were apparent between different milking systems for up to 4 h postmilking.

scholarly journals Influence of low vacuum levels on milking characteristics of sheep, goat and buffalo

2013 ◽  
Vol 44 (2s) ◽  
Author(s):  
Maria Caria ◽  
Carlo Boselli ◽  
Lelia Murgia ◽  
Remo Rosati ◽  
Antonio Pazzona
Keyword(s):  
High Vacuum ◽  
Vacuum Level ◽  
Machine Milking ◽  
The World ◽  
Study Characteristics ◽  
Principal Factors ◽  
Low Levels ◽  
Kinetics Of ◽  
Teat Canal ◽  
Different Parts

Different settings of the operating parameters (pulsator rate, pulsator ratio and vacuum) are used for milking dairy species in different parts of the world. The level of the operating vacuum in machine milking is one of the principal factors which influence the integrity of the tissues and the milk quality. High vacuum levels (&gt;42 kPa) are often used to facilitate the opening of the teat canal by overcoming the biological closing forces whithin the teat sphincter, but can result in severe machine-induced teat tissue damage. In this study characteristics and performances of mechanical milking at low vacuum levels have been investigated in different dairy species. Milking times and milk productions have been obtained from milk emission curves, recorded by electronic milk-meters (LactoCorder®) during the milking at different vacuum levels of sheep, goats and buffaloes. The results of the comparative experiments clearly indicate that a low vacuum level modifies the kinetics of milk emission, the machine-on time and, thus, the throughput of milking system, in all the dairy species considered. Milk yield was satisfactory at any level tested, showing that low vacuums can be adequate to completely empty the udder. Slight differences were found across species concerning the increase in the milking time per head associated with low levels of milking vacuum Our study represents a contribution to encourage the decrease of the working vacuum during mechanical milking, also for those dairy species generally considered hard to be milked, as buffaloes. Milking should be performed applying the lowest vacuum level, compatible with not excessively prolonging milking time, in line with the animal welfare on dairy husbandry.

scholarly journals Changes in teat parameters caused by milking and their recovery to their initial size

2010 ◽  
Vol 53 (6) ◽  
pp. 650-662
Author(s):  
L. Stádník ◽  
F. Louda ◽  
J. Bezdíček ◽  
A. Ježková ◽  
M. Rákos
Keyword(s):  
Dairy Cows ◽  
Somatic Cell ◽  
Cell Count ◽  
Wall Thickness ◽  
Somatic Cell Count ◽  
Initial Size ◽  
Linear Description ◽  
Daily Milk Yield ◽  
Teat Canal ◽  
Daily Milk

Abstract. Dairy cows of 2 breeds, 74 Holstein (H) and 72 Czech Fleckvieh (C) cows in the 1st (H, n=38; C, n=38) and 2nd lactation (H, n=36; C, n=34) during the 1st period (n=74; H, n=40; C, n=34; to 150 days) and the 2nd period of lactation (n=72; H, n=34; C, n=38; above 150 days) were observed. Differences in external and internal proportions of teat closely before (the 1st measurement), immediately after (the 2nd measurement) and 3 h after milking (the 3rd measurement), udder conformation evaluated by linear description, somatic cell count, daily milk yield and the time of milking were evaluated in relation to the effect of breed and period of lactation. The length of the teat canal, area of the teat end, and wall thickness were measured from the axial picture recorded by ultrasound Aloka SSD500 (Aloka Co., Ltd., Tokyo, Japan). Significant interbreed differences were detected in external as well as internal teat proportions (P<0.05–0.001). Relative changes of teat diameter, comparing C and H cows, differed significantly between the 1st and the 3rd measurement (P<0.05). The length of teat increased during milking and didn´t achieve the beginning size during 3 h after milking. Significant diiference in the length of teat between the 2nd measurement and the 3rd measurement was determined in H cows only (P<0.001). The most significant changes of the length of the teat canal and the area of teat were found in both breeds between values measured closely before and immediately after milking (P<0.5–0.001). Wall thickness was strengthen in C cows (+15.6 %) during the 2nd measurement according to the 1st (P<0.05), while difference represented +18 % (P<0.001) in H cows. Non-significantly higher values of external proportions of teat were measured in the 2nd period of lactation except diameter of teat closely before milking. Internal proportions of teat were always significantly higher in the 2nd period of lactation in relation to the 1st period. Prolongation of teat canal by 0.15 cm (P<0.01) closely before, by 0.16 cm (P<0.001) immediately after, and by 0.13 cm (P<0.01) 3 h after milking was measured in the 2nd period of lactation. The area of teat end measured before milking was significantly larger in the 2nd period of lactation (P<0.01).

Increased milking vacuum in teatcups fitted with non-return valves

1988 ◽  
Vol 55 (4) ◽  
pp. 495-503 ◽  
Author(s):  
R. Jeffrey Andrews ◽  
Graeme A. Mein ◽  
David M. Williams
Keyword(s):  
Strain Energy ◽  
Air Leakage ◽  
Bench Tests ◽  
Vacuum Level ◽  
Milk Flow ◽  
The Mean ◽  
Pulsation Cycle ◽  
Return Valve ◽  
Maximum Pulsation ◽  
Collapse Phase

SummaryAn experimental non-return valve was fitted in the short milk tube so that flow was permitted only in one direction, away from the teat. Liner movement was minimal because no air admission to the liner above the valve was provided. The extent of liner opening therefore depended on the amount of milk extracted within a pulsation cycle and on any air leakage past the liner mouthpiece. Milking experiments using four cows showed that the mean vacuum level in nominally open liners of valved teatcups during peak milk flow was 8·6 kPa higher than in conventional teatcups. Bench tests showed that the increase in liner vacuum (LV) depended on the nominal plant vacuum level, the pressure difference between initial LV and maximum pulsation chamber vacuum, the liner elasticity and mounting tension. The main source of energy available to raise LV above the nominal plant vacuum is the release of strain energy, stored within the liner during the collapse phase of each pulsation cycle.

A1Bi3C6 Thin Films as NO Sensors

2006 ◽  
Vol 915 ◽  
Author(s):  
Halyna Khlyap ◽  
Violetta Bilozertseva ◽  
Nina Dyakonenko ◽  
Dmitrii Gaman ◽  
Andrey Mamalui ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Film Surface ◽  
Electrophysical Properties ◽  
Growth Morphology ◽  
Vacuum Level ◽  
Glass Substrates ◽  
Aggressive Environment ◽  
Vacuum Technology ◽  
Before And After

AbstractThe paper reports experimental data on growth, morphology, NO sensitivity and electrophysical properties of A1Bi3C6 thin films obtained by means of simple vacuum technology. The investigated samples were condensed onto the glass substrates under deposition rate 0.1-0.5 nm/s at T = 300 K and vacuum level P = 10-3 Pa. AFM investigations of the film surface before and after interaction with aggressive environment demonstrated sufficient sensitivity of the film relief to the aggressive component. Room-temperature electric field-induced characteristics were investigated for metal-semiconductor (MS) Cr/NaBiTe2 structures.

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