THE FUNCTIONAL CONTROLABILITY OF MILK EJECTION OF THE ADAPTIVE MILKING SYSTEM

The concept of functional controllability of the milk ejection is considered, which makes it possible to predict the intensity of milk ejection in the online mode of the milking machine. The architecture of the functional controllability by intensity of milk ejection is developed. Input and output parameters of the structural-functional scheme of adaptive control of milk ejection intensity are described. An analytical model of milk ejection intensity based on Pearson's distribution is developed. The milk ejection intensity for different productivity and duration of cows milking is modelled. The microprocessor unit is designed using a single-chip microcontroller. It ensures the algorithm set by the central computer and implements a step of changing the pulsation frequency of 0.1 Hz, the ratio between the cycles of 0.25%, the phase shift step of 0.1 s.

Early mechanical stimulation of the nipple-areola receptors complex promotes the mammary milk ejection function in women delivered by cesarean section

Mechanical stimulation and milk ejection from mammary gland in women delivered by caesarean section since 1 day post partum by the breastpump with vacuum and compression stimuli promotes milk ejection function. On the third day postpartum the stimulated mothers had significantly more milk flow reflex peaks than those who were not subjected to stimulation during the 10 min milk ejection session.

Dysphoric Milk Ejection Reflex: The Psychoneurobiology of the Breastfeeding Experience

Breastfeeding, given its biochemical and physiological basis, is known for its many benefits for both the lactating mother and the infant. Among the many challenges new breastfeeding mothers experience is the feeling of aversion in response to their newborn's suckling which has been termed dysphoric milk-ejection reflex (D-MER). Characterized by intense feelings of dysphoria which may eventually interfere with the mother's ability to breastfeed regularly, evidence suggests both the neurobiological and psychological basis of D-MER in an attempt to explain its complexity. Biologically, breastfeeding is expressed by the intracerebral release of oxytocin, an increased expression of oxytocin receptors in specific brain regions, increased mesocorticolimbic reward region activation, the secretion of prolactin and possibly the inhibition of dopamine. Hence, different theories explain D-MER in terms of disrupted neurotransmitter and hormonal activity. Breastfeeding has also proven to influence mood and stress reactivity in nursing mothers with a potential link with postpartum depression. Psychological theories attempt to explain D-MER from a sociopsychosexual lense shedding light on the significance of mother-infant attachment, the sexualization of the female body and the motherhood experience as a developmental stage in a woman's lifespan. The aim of this review is to provide a literature update of D-MER incorporating both neurobiological and psychological theories calling for raising awareness about the complexity of breastfeeding and for the need for mother-centered interventions for the management of D-MER and other postpartum-specific conditions.

ELECTION AND GENETIC PARAMETERS OF THE INTENSITY OF MILK PRODUCTION IN COWS

The study of the main technological feature of the Kholmogorsky breed of the Tatarstan type-milk ejection intensity-showed that its increased variability is characterized by high-blood crossbreeds, as well as animals of the Astronaut and Sovering lines. The high and low genetic potential of parental productivity reduces the variability of milk ejection intensity. However, selection for an increase in milk content will not be accompanied by an improvement in the intensity of milk ejection, since the established phenotypic correlation is mainly negative or positive at a low level. In this regard, it is necessary to control both productive and technological characteristics.

Recording and neural circuit-based manipulation of the maternal oxytocin pulses in mice

For mammals, successful parturition and breastfeeding are critical to the survival of offspring. Pulsatile release of the hormone oxytocin mediates uterine contraction during parturition and milk ejection during lactation. These oxytocin pulses are generated by unique activity patterns of the central neuroendocrine oxytocin neurons located in the paraventricular and supraoptic hypothalamus. However, the maternal activities of oxytocin neurons remain elusive because most classical electrophysiological studies in anesthetized rats have lacked the genetically defined cell identity of oxytocin neurons. We herein introduce viral genetic approaches in mice to characterize the maternal pulsatile activities of oxytocin neurons by fiber-photometry-based chronic in vivo Ca2+ imaging. We also demonstrate the pharmaco-genetic manipulation of oxytocin pulses during lactation via activating a prominent pre-synaptic structure of oxytocin neurons defined by retrograde trans-synaptic tracing. Collectively, our study opens a new avenue for the neuroscience of maternal neuroendocrine functions.

Oxytocin and cortisol release during suckling, hand-milking and machine milking in camels

This research paper addresses the hypothesis that oxytocin (OT) could be released during suckling and during milking with and without the presence of a calf and that this release could be regulated by maternal behaviour. Plasma concentration patterns of OT and cortisol (CORT) were measured in six Tunisian dromedary camels during 2 suckling episodes, 2 manual milking episodes with calves beside the mother and 2 machine milking episodes without calves present. Various patterns of OT release were observed between each camel including specific two peak release patterns. Higher plasma OT concentrations were found during the suckling and hand-milking episodes with simultaneous suckling of calves, than during the machine milking episodes without calves. Exclusive mechanical milking episodes also evoked significant mean OT release, although greatly reduced compared to suckling and hand milking. The low basal levels and classical CORT release patterns suggested non-stressful management practices were used and there were very limited differences in udder stimulation between managements. The OT release induced by exclusive suckling and suckling together with hand-milking gives a reference point for what a good milk ejection stimulation is in camels. The important and specific reduction of OT release during machine milking without the calf present could be a physiological consequence of the maternal behaviour (selectivity for the own young) and to a lesser extent explained by a lower stimulation by machine milking.

Oxytocin Involvement in Body Composition Unveils the True Identity of Oxytocin

The origin of the Oxytocin/Vasopressin system dates back about 600 million years. Oxytocin (Oxt) together with Vasopressin (VP) regulate a diversity of physiological functions that are important for osmoregulation, reproduction, metabolism, and social behavior. Oxt/VP-like peptides have been identified in several invertebrate species and they are functionally related across the entire animal kingdom. Functional conservation enables future exploitation of invertebrate models to study Oxt’s functions not related to pregnancy and the basic mechanisms of central Oxt/VP signaling. Specifically, Oxt is well known for its effects on uteri contractility and milk ejection as well as on metabolism and energy homeostasis. Moreover, the striking evidence that Oxt is linked to energy regulation is that Oxt- and Oxytocin receptor (Oxtr)-deficient mice show late onset obesity. Interestingly Oxt−/− or Oxtr−/− mice develop weight gain without increasing food intake, suggesting that a lack of Oxt reduce metabolic rate. Oxt is expressed in a diversity of skeletal muscle phenotypes and regulates thermogenesis and bone mass. Oxt may increases skeletal muscle tonicity and/or increases body temperature. In this review, the author compared the three most recent theories on the effects of Oxt on body composition.

Oxytocin receptor induces mammary tumorigenesis through prolactin/p-STAT5 pathway

Oxytocin receptor (OXTR) is involved in social behaviors, thermoregulation, and milk ejection, yet little is known about its role in breast cancer. To investigate the role of OXTR in mammary gland development and tumorigenesis, a transgenic mouse model of OXTR overexpression (++Oxtr) was used. Overexpression of OXTR-induced progressive mammary hyperplasia, unexpected milk production, and tumorigenesis in females. OXTR-induced mammary tumors showed ERBB2 upregulation and mixed histological subtypes with predomination of papillary and medullary carcinomas. OXTR overexpression led to an activation of prolactin (PRL)/p-STAT5 pathway and created a microenvironment that promotes mammary-specific tumorigenesis. PRL inhibitor bromocriptine (Br) could mitigate OXTR-driven mammary tumor growth. The study demonstrates Oxtr is an oncogene and a potential drug target for HER2-type breast cancer.

Milk production process, quality and technological properties of milk for the use of various types of milking machines

Studies have been carried out to evaluate the efficiency of using easy-assembled cow houses in modern milk production technologies for the use of high-productive milking plants of the type ‘Parallel’ and ‘Carousel’ with 32 machines each. It has been established that new types of premises not only provide comfortable conditions for the maintenance of highly productive cows, but also reduce the labor costs for their maintenance and, most importantly, allow the use of modern high-productive milking installations of the type ‘Parallel’ and ‘Carousel’. It has been established that the technology of preparation of cows for milking and milking technology provides more complete display of the milk ejection reflex at the installation of the ‘Parallel’ type. The average intensity of cows’ milk flows at this plant is 30% higher compared to those of the installation of ‘Carousel’ type, which is confirmed by the intensity of milk flow production at the first minute of milking, which is at the level of 2.97 against 1.85 kg min.-1 per installation of ‘Carousel’ type. Milk obtained using a milking installation of the ‘Parallel’ type has higher values of the mass fraction of fat and protein that is associated with the genetic potential of animals. According to physical, chemical and technological properties, milk obtained from milking installations such as ‘Parallel’ and ‘Carousel’ is within the limits of the standards in force. Milk obtained from the use of milking equipment such as ‘Carousel’ has higher electrical conductivity at the level of 4.6 mS cm-3, which is confirmed by a higher level of mastitis disease of cows. Due to bacterial contamination, reductase test and milk clot characteristic, milk obtained using a milk installation of ‘Parallel’ type also has higher quality indicators than the installation of ‘Carousel’ type. But according to the complex of indicators, milk obtained from various technologies of milking refers to the desired cheese-making class.

Role of hypocretin in the medial preoptic area in the regulation of sleep, maternal behavior and body temperature of lactating rats.

The hypocretins (HCRT), also known as orexin, includes two neuroexcitatory peptides, HCRT-1 and HCRT-2 (orexin A y B, respectively), synthesized by neurons located in the postero-lateral hypothalamus, whose projections and receptors are widely distributed throughout the brain, including the medial preoptic area (mPOA). HCRT have been associated with a wide range of physiological functions including sleep-wake cycle, maternal behavior and body temperature, all regulated by the mPOA. Previously we showed that HCRT in the mPOA facilitates certain active maternal behaviors, while the blockade of HCRT-R1 increased the time spent in nursing. As mother rats mainly sleep while they nurse, we hypothesize that HCRT in the mPOA of lactating rats reduce sleep and nursing, while the intra-mPOA administration of the dual orexin receptor antagonist (DORA) would generate the opposite effect. Therefore, the aim of this study was to determine the role of HCRT within the mPOA, in the regulation and integration of the sleep-wake cycle, maternal behavior and body temperature of lactating rats. To evaluate this idea, we assessed the sleep-wake states, maternal behavior and body temperature of lactating rats following microinjections of HCRT-1 (100 and 200 uM) and DORA (5mM) into the mPOA. As expected, our data shows that HCRT-1 in mPOA promoted wakefulness and a slightly increase in body temperature, whereas DORA increased both NREM and REM sleep along with nursing and milk ejection. Taken together, our results strongly suggest that the reduction of the endogenous HCRT within the mPOA of lactating rats is important to promote sleep, nursing and milk ejection.