scholarly journals Milk removal in familiar and unfamiliar surroundings: concentrations of oxytocin, prolactin, cortisol and β–endorphin

1993 ◽  
Vol 60 (4) ◽  
pp. 449-456 ◽  
Author(s):  
Rupert M. Bruckmaier ◽  
Dieter Schams ◽  
Jürg W. Blum
Keyword(s):  
The Other ◽  
Operating Theatre ◽  
Flow Curves ◽  
Blood Samples ◽  
Milk Flow ◽  
Total Milk ◽  
Oxytocin Release ◽  
Central Inhibition ◽  
Vaginal Stimulation

SummaryEight cows were machine milked either in an operating theatre or in their familiar barn. During the experiments, milk flow curves were recorded and blood samples were taken for determination of concentrations of oxytocin, prolactin, cortisol and β–endorphin. The milking cluster was attached without udder preparation. After cessation of milk flow, air was blown into the vagina for 2 min. When milk flow had stopped again, 1 i.u. oxytocin and finally 10 i.u. oxytocin were injected to remove the remaining milk. After the start of milking, oxytocin remained basal in unfamiliar, but increased in familiar surroundings. Therefore, during normal milking only 9% of total milk was removed in unfamiliar, whereas 79% was available in familiar surroundings. In response to subsequent vaginal stimulation in the operating theatre, oxytocin increased transiently in five cows and 15–71% of the milk was removed in these animals. In the other three cows in the operating theatre, oxytocin remained basal during vaginal stimulation, and no more milk was available. After injection of 1 i.u. oxytocin, 56 and 11%, and after injection of 10 i.u. oxytocin, 13 and 8% of milk was removed in unfamiliar and familiar surroundings respectively. Concentrations of prolactin increased during the course of milking in both treatments. Premilking concentrations of cortisol and β–endorphin were elevated in unfamiliar as compared with familiar surroundings. During the course of milking, cortisol increased slightly and β–endorphin decreased in unfamiliar, whereas both hormones increased markedly during milking in familiar surroundings. We conclude that disturbed milk removal in unfamiliar surroundings is due to central inhibition of oxytocin release during normal milking and partly also to a response to vaginal stimulation. This blockade is possibly associated with elevated concentrations of β–endorphin.

scholarly journals Milk yield, oxytocin and β-endorphin gradually normalize during repeated milking in unfamiliar surroundings

1996 ◽  
Vol 63 (2) ◽  
pp. 191-200 ◽  
Author(s):  
Rupert M. Bruckmaier ◽  
Hans-Ulrich Pfeilsticker ◽  
Jürg W. Blum
Keyword(s):  
Dairy Cows ◽  
Milk Yield ◽  
Control Level ◽  
Operating Theatre ◽  
Milk Ejection ◽  
Asymptotic Approach ◽  
Blood Samples ◽  
Milk Flow ◽  
Total Milk ◽  
Oxytocin Release

SummaryFor six successive milkings, six dairy cows were relocated immediately before milking to an unfamiliar operating theatre, a procedure previously shown to inhibit oxytocin release and milk ejection. Two control milkings were performed in familiar surroundings. After milk flow had ceased, two i.v. injections of 1 i.u. oxytocin were given to remove the remaining milk. Milk flow was recorded continuously and blood samples were taken every minute during milking and 10 min after milking. During the first milking in unfamiliar surroundings, no oxytocin was released. Thereby, only 13% of the total milk yield, the cisternal milk, was available and the alveolar milk fraction could only be removed after injection of oxytocin. During subsequent relocations oxytocin release steadily increased toward the control level, although the timing of oxytocin release remained delayed as compared with controls. However, the milk fraction available before oxytocin injection increased with increasing number of removals, following an asymptotic approach to control levels. The concentrations of β-endorphin, cortisol (and perhaps also of prolactin) gradually declined with the number of times the animal was moved to unfamiliar surroundings, i.e. hormone concentrations gradually adjusted to control level. During milking, concentrations of prolactin and cortisol increased, while β-endorphin concentrations decreased (except for the first relocation). We conclude that milking-related oxytocin release and therefore milk ejection adapted gradually to repeated relocations to unfamiliar surroundings. This adaptation was inversely related to β-endorphin concentrations, so it is possible that oxytocin release was suppressed by high circulating β-endorphin concentrations.

scholarly journals Simultaneous recording of oxytocin release, milk ejection and milk flow during milking of dairy cows with and without prestimulation

1996 ◽  
Vol 63 (2) ◽  
pp. 201-208 ◽  
Author(s):  
Rupert M. Bruckmaier ◽  
Jürg W. Blum
Keyword(s):  
Flow Rate ◽  
Simultaneous Recording ◽  
Milk Ejection ◽  
Flow Curves ◽  
Milk Flow ◽  
Oxytocin Release ◽  
Plateau Time ◽  
Milking Machine ◽  
Left Front

SummaryThe effects of manual teat stimulation compared with stimulation by the liner of a conventional milking machine and the influence of milk ejection on the course of milk flow during the entire milking were investigated. Twelve cows were milked with or without prestimulation on three quarters and milk flow was recorded while intramammary pressure (IMP) was recorded in the left front quarter and blood samples for the determination of oxytocin (OT) were taken at 1 min intervals. OT concentrations increased very similarly in response to manual teat stimulation or liner stimulation and remained elevated during the entire milking procedure. Milk flow curves were generally bimodal without stimulation and not bimodal during milking after prestimulation. Milk yield was not significantly lower in milkings without than with stimulation, whereas machine-on time was prolonged and peak milk flow rate was reduced during milking without stimulation. Time to reach milk flow plateau, time to reach peak flow rate and IMP profiles were similar in both treatments if time was calculated from the start of stimulation. IMP increased similarly in response to manual or liner teat stimulation. In milkings with and without prestimulation IMP did not reach its maximum until the start of milking. In bimodal milk flow curves the second increase of milk flow occurred concomitantly with the start of IMP increase; ejection IMP generally occurred concomitantly with the milk flow plateau. In some cases during milking without prestimulation only small and transient OT release was observed. In response, IMP did not increase to its maximum and increased further in response to a stripping-related OT release. During the course of milking IMP decreased slightly because of the emptying of the three milked quarters. After the end of milking, and with OT concentrations decreasing to the premilking values, IMP again decreased slightly to another plateau, probably owing to myoepithelial relaxation. Thus the course of milk ejection, i.e. the IMP profile, influenced milk removal markedly during early milking.

scholarly journals Aetiology of disturbed milk ejection in parturient primiparous cows

1992 ◽  
Vol 59 (4) ◽  
pp. 479-489 ◽  
Author(s):  
Rupert M. Bruckmaier ◽  
Dieter Schams ◽  
Jürg W. Blum
Keyword(s):  
Luteinizing Hormone ◽  
Milk Ejection ◽  
Blood Samples ◽  
Machine Milking ◽  
Milk Flow ◽  
Total Milk ◽  
Basal Concentration ◽  
Vaginal Stimulation

SummaryMilk flow in nine primiparous cows with disturbed milk ejection (D) and in six corresponding control animals (C) with normal milk removal was recorded during machine milking and blood samples were taken before and during milking to determine plasma oxytocin, vasopressin. prolactin, cortisol, oestradiol-17β, luteinizing hormone, progesterone and β-endorphin concentrations. Manual teat stimulation before milking lasted for 1 min. After milk flow had stopped, air was blown into the vagina for 2 min. When milk flow had stopped again, 1 i.u. oxytocin and finally 10 i.u. oxytocin were injected to remove residual milk. During and after teat stimulation, oxytocin remained basal in D, but increased in C, whereas prolactin increased in both groups. While 94% of total milk was obtained in C during this period, only 9% could be removed from D, indicating lack of alveolar milk ejection. During vaginal stimulation, oxytocin increased transiently in D and more than by teat stimulation in C. This allowed the removal of 75% of milk in D, whereas almost no more milk was available in C. After oxytocin injections, 3 and 16% of residual milk were obtained in C and D respectively. Basal oestradiol-17β concentration was higher in D than in C (11·6 and 2·0 ng/1 respectively), whereas β-endorphin level was lower (24·1 and 86·6 μg/1 respectively). Basal concentration of luteinizing hormone and progesterone, and concentration of cortisol and vasopressin before and during milking were comparable in C and D. We conclude that in cows with disturbed milk ejection afferent nervous pathways to the hypothalamus were intact, because prolactin was released by teat stimulation. However, oxytocin was only released by vaginal stimulation, i.e. milk ejection was centrally inhibited during teat stimulation.

Effect of suckling during early lactation and changeover to machine milking on plasma oxytocin and cortisol levels and milking characteristics in Holstein cows

1995 ◽  
Vol 62 (2) ◽  
pp. 249-256 ◽  
Author(s):  
Vladimír Tančin ◽  
L'Ubomír Harcek ◽  
Ján Brouček ◽  
Michal Uhrinčať ◽  
Štefan Mihina
Keyword(s):  
Milk Yield ◽  
Flow Rate ◽  
Plasma Concentrations ◽  
The Other ◽  
Early Lactation ◽  
Flow Rates ◽  
Blood Samples ◽  
Machine Milking ◽  
The Third ◽  
Oxytocin Release

SUMMARYPlasma concentrations of oxytocin and cortisol, and milk yield and flow rates, were compared in three primiparous cows and two cows in their second lactation during suckling and subsequent machine milking. After calving, cows suckled their calves for 3–4 weeks and then the experiment was carried out over 4 d. Blood samples were taken prior to, during and after suckling or evening machine milking (EMM) on day 1 of the experiment (the last day of suckling), day 2 (first EMM) and day 4 (third EMM). After weaning and rehousing, cows were machine milked twice daily. During the first EMM, average milk yield and flow rate in the second minute of milking were significantly lower (P < 0·05) than corresponding values for the other 2 d. Plasma oxytocin concentrations were lower during the first than during the third EMM (P < 0·001) and suckling (P < 0·001), and more oxytocin was released during the third EMM than during suckling (P < 0·01). Cortisol concentrations were higher during and after the first EMM than during the third EMM. Thus in cows sucked for several weeks after calving and then separated from their calves and rehoused we found a transient decrease in oxytocin release, milk yield and flow rates during the first machine milking.

Methods compared for determining glutathione peroxidase activity in blood.

1987 ◽  
Vol 33 (4) ◽  
pp. 539-543 ◽  
Author(s):  
B Faraji ◽  
H K Kang ◽  
J L Valentine
Keyword(s):  
Glutathione Peroxidase ◽  
Peroxidase Activity ◽  
Reference Intervals ◽  
The Other ◽  
Specific Time ◽  
Glutathione Peroxidase Activity ◽  
Time Intervals ◽  
Indirect Methods ◽  
Blood Samples

Abstract We compared four methods for determination of glutathione peroxidase (EC 1.11.1.9) activity, using blood samples from 52 healthy volunteers. Two methods depended on direct assay of the amount of glutathione remaining at specific time intervals; the two indirect methods involved measuring the rate of disappearance of NADPH. We assessed the precision and reproducibility of each method. One of the indirect assays proved to be far superior to the other methods. Results of each of the methods were correlated with one another. We present the normal reference intervals for glutathione peroxidase activity for all four methods.

scholarly journals  The level of udder emptying and milk flow stability in Tsigai, Improved Valachian, and Lacaune ewes during machine milking

2012 ◽  
Vol 57 (No. 5) ◽  
pp. 240-247 ◽  
Author(s):  
L. Mačuhová ◽  
V. Tančin ◽  
M. Uhrinčať ◽  
J. Mačuhová
Keyword(s):  
Milk Production ◽  
Flow Curve ◽  
Frequency Of Occurrence ◽  
Flow Curves ◽  
Machine Milking ◽  
Milk Flow ◽  
Total Milk ◽  
The Stability ◽  
June July ◽  
Daily Milk

The objective of this investigation was to evaluate the stability of milk flow curves and the volume of residual milk in relation to milk flow curves in breeds Tsigai, Improved Valachian, and Lacaune (n&nbsp;= 16 heads per breed) milked twice daily. Milk flow type stability was evaluated at morning milking (stabile milkings) during three successive days in the middle of two months (June, July). After the following fourth morning milking (OT milkings) in both months, oxytocin was injected intravenously at a dose of 2&nbsp;UI. Afterwards the ewes were milked again in order to remove residual milk. The milk flow curves were classified into four types: 1 peak (1P), 2 peaks (2P), plateau I (maximal milk flow over 0.4 l/min) (PLI), plateau II (maximal milk flow less than 0.4 l/min) (PLII). If all milk flow curves of one animal were of the same type within one month and within both months, respectively, the animal was characterized as the ewe with the stabile type of milk flow. Frequency of occurrence of single milk flow types (1P : 2P : PLI : PLII) during stabile milkings was 42 : 49 : 9 : 0% in June and 51 : 37.5 : 11.5 : 0% in July. 33 ewes (i.e. 69%) had the stabile type of milk flow within both months. But, more than 51% of them had 1P type of milk flow. Milk production varied according to milk flow curve during OT milkings (0.427 &plusmn; 0.015, 0.498 &plusmn; 0.024, and 0.655 &plusmn; 0.035 l for 1P, 2P, and PLI, respectively). The highest percentage of residual milk from total milk yield (RM/TMY) was observed in ewes with 1P (20.29 &plusmn; 0.85%), followed by ewes with PLI (12.31 &plusmn; 1.99%) and 2P (9.72 &plusmn; 1.36%) (P &lt; 0.0001). Lacaune ewes had the lowest amount of residual milk (0.054 &plusmn; 0.006 l) and RM/TMY (9.86 &plusmn; 1.16%) compared to breeds Tsigai (0.088 &plusmn; 0.008 l; 16.47 &plusmn; 1.44%) and Improved Valachian (0.069 &plusmn; 0.010 l; 15.99 &plusmn; 1.78%) indicating their better udder emptying. &nbsp;

Inhibition of oxytocin release during repeated milking in unfamiliar surroundings: the importance of opioids and adrenal cortex sensitivity

2002 ◽  
Vol 69 (1) ◽  
pp. 63-73 ◽  
Author(s):  
JULIANA MAČUHOVÁ ◽  
VLADIMIR TANČIN ◽  
WOLF-DIETER KRAETZL ◽  
HEINRICH H. D. MEYER ◽  
RUPERT M. BRUCKMAIER
Keyword(s):  
Endogenous Opioids ◽  
Opioid Antagonist ◽  
Control Group ◽  
Research Station ◽  
Milk Ejection ◽  
Milk Flow ◽  
Oxytocin Release ◽  
And Control ◽  
Naloxone Treatment ◽  
Vaginal Stimulation

The aim of this study was to test if the opioid antagonist naloxone has a beneficial effect on normalization of oxytocin (OT) release during repeated milking of cows in unfamiliar surroundings. One control milking without naloxone treatment in all cows was performed in the familiar parlour. For four successive evening milkings, cows were transported to, and milked in, the operating theatre of the research station without (control group) or with naloxone administration (1 mg/kg BW) (naloxone group) before milking. After cessation of spontaneous milk flow, but not before 3 min of milking, vaginal stimulation was applied for 2 min. After milk flow ceased again, 10 IU of OT was injected intravenously to remove the remaining milk including residual milk. Milk flow was recorded continuously and blood samples were collected via a jugular vein cannula at 1-min intervals from 1 min before the start of milking until i.v. injection of OT. The inhibition of milk ejection and its normalization during repeated milking in unfamiliar surroundings was not influenced by naloxone treatment. Concentrations of cortisol and β-endorphin during control milking and all relocations were similar in the naloxone and control groups, although their concentrations were higher after relocations than in the control. Therefore, a role of endogenous opioids in the inhibition of milk ejection in unfamiliar surroundings could not be demonstrated. In addition, the effect of exogenous ACTH1–24 (8 IU, i.v.) on the release of cortisol related to the response of cows milked in unfamiliar surroundings was studied. Cows with totally inhibited milk ejection in response to vaginal stimulation during milking after first relocation had numerically, but not significantly lower cortisol levels (8·8±3·4 ng/ml; AUC/min) in response to ACTH than did cows with at least partial milk ejection (38·7±12·9 ng/ml). Thus animals with a higher adrenal response to ACTH seemed to have less severe inhibition of milk ejection.

scholarly journals Reduced claw vacuum and b-phase during low milk flow does not impact oxytocin release and milking performance

2017 ◽  
Vol 85 (1) ◽  
pp. 70-77
Author(s):  
Anna-Lena Neuheuser ◽  
Ann-Catherine Schwinn ◽  
Olga Wellnitz ◽  
Lorenzo E. Hernández-Castellano ◽  
Rupert M. Bruckmaier
Keyword(s):  
Wall Thickness ◽  
Cross Sections ◽  
Peak Flow ◽  
Milk Ejection ◽  
Flow Curves ◽  
Flow Rates ◽  
Milk Flow ◽  
Oxytocin Release

Oxytocin release, milking characteristics, and teat condition were investigated with reduced claw vacuum and pulsation settings compared to milking at regular settings with or without pre-stimulation. The reduced vacuum and pulsation settings during low milk flow are expected to protect the teat tissue before the occurrence of milk ejection at the start of milking, and at the end of milking during a potential overmilking period, i.e. at a milk flow <200 g/min. Seven cows were machine-milked either after a 60 s manual pre-stimulation, or without pre-stimulation and reduced vacuum and pulsation settings, or at full vacuum and normal pulsation during the start of milking. Plasma oxytocin (OT) concentration increased similarly in response to manual pre-stimulation and to both milking with reduced, or with full vacuum and pulsation settings, however delayed by 1 min if the cluster was attached without pre-stimulation. In all treatments OT concentrations remained elevated throughout milking. Milk flow curves were mostly non-bimodal at milkings after manual pre-stimulation and bimodal at milkings without pre-stimulation. The main milking time was shorter and average milk flow was higher during milking after pre-stimulation, but did not differ between treatments without pre-stimulation. Milk yields and peak flow rates were not affected by treatments. Either reduced or full vacuum settings were again applied during an intended overmilking from 200 to 100 g/min of milk flow towards the end of milk harvest. Pre-milking teat ultrasound cross sections were recorded one day before the experiment started. Post-milking ultrasound cross sections were performed at 15 min after each experimental milking. Teat wall thickness was increased after milking as compared to pre-milking but did not differ among treatments. In conclusion, OT release and milking performance are similar if milking is performed with pre-stimulation, or without pre-stimulation but reduced claw vacuum and b-phase during low milk flow.

scholarly journals Quarter milk flow patterns in dairy cows: factors involved and repeatability

2012 ◽  
Vol 48 (No. 10) ◽  
pp. 275-282 ◽  
Author(s):  
V. Tancin ◽  
A.H. Ipema ◽  
D. Peskovicova ◽  
P.H. Hogeverf ◽  
J. Macuhova
Keyword(s):  
Milk Yield ◽  
Flow Rate ◽  
Peak Flow ◽  
Clinical Mastitis ◽  
Plateau Phase ◽  
Peak Flow Rate ◽  
Flow Parameters ◽  
Milk Flow ◽  
Total Milk

The objectives of our study were to describe the variation of quarter milk flow parameters and to determine the factors that affect these parameters the most. Additionally, repeatabilities (r<sub>2</sub>) of the quarter milk flow traits (duration of milk flow, time to reach peak flow, peak flow rate, and duration of milk flow in single phases &ndash; increase, plateau, decline and blind phase) were calculated. Repeatability of total milk yield and milk yield in single phases was calculated, too. The data from 39 Holstein cows, in their first to third lactation and free of clinical mastitis, were used for statistical analysis. A total of 1 656 curves of quarter milk flows were recorded during six consecutive days. At the last evening and morning milking samples of milk from each quarter were collected for determination of somatic cell count (SCC). Peak flow rate, quarter position, time of milking (morning and evening) and SCC significantly affected most of the measured traits. The highest r2 were for total milk yield and yield of plateau phase 0.53 and 0.50, resp. The lowest r2 were calculated for the duration of increase phase, and milk yield of the increase and blind phase 0.26, 0.12 and 0.21, resp. Peak flow rate, SCC, time of milking and front-rear position influenced the values of r2 of traits to various extent.

Simultaneous and independent release of vasopressin and oxytocin in the rat

1988 ◽  
Vol 66 (1) ◽  
pp. 22-26 ◽  
Author(s):  
Norman W. Kasting
Keyword(s):  
Hypertonic Saline ◽  
Arginine Vasopressin ◽  
Restraint Stress ◽  
Animal Species ◽  
The Other ◽  
Sampling Techniques ◽  
Vasopressin Release ◽  
Blood Samples ◽  
Oxytocin Release ◽  
Relative Dependence

The relative dependence or independence of the secretion of the neurohypophysial hormones, arginine vasopressin and oxytocin, was investigated using a wide variety of stimuli reported to cause the secretion of one or the other hormone. Differences in species, animal preparations, sampling techniques, assays, and other factors make comparison of many previous studies difficult. The aim of this study was to overcome these problems by using the same methodology, animal species, and assays to compare vasopressin and oxytocin release. To further strengthen the analysis, determinations of vasopressin and oxytocin were done in the same blood samples. The results demonstrated that during simultaneous release of both hormones, vasopressin is released in greater proportion following restraint stress, hemorrhage, isotonic hypovolemia, and nicotine, whereas oxytocin is released in greater proportion following endotoxin or hypertonic saline. Vasopressin was released without oxytocin following diethylstilbestrol. Oxytocin was released without concomitant vasopressin release following exercise, hypothermia, hyperthermia, labour, and lactation. Neither oxytocin nor vasopressin release was observed following thyroid-releasing hormone or insulin-induced hypoglycemia. These data illustrate the marked flexibility of the hypothalamo-neurohypophysial system that regulates secretion of vasopressin and oxytocin.

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