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<p><strong>Purpose:</strong> The review summarizes major research that contributed to the organizational life cycle theory, discusses major issues and contradictions of the theory and offers additional assumptions about the organizational life cycle. Based on that, it attempts to offer a future research agenda for the theory.</p><p><strong>Methodology/Approach:</strong> The paper uses narrative review; the list of included life cycle models stems from previous summaries of the theory and subsequent snowball search through reference lists of individual reviewed papers.</p><p><strong>Findings:</strong> The theory is rich with various life cycle models that nevertheless converge on some major characteristics. Organizational life cycle can be described with classical five stages: (i) founding, (ii) growth, (iii) maturity, (iv) decline, and (v) revival. However, the stages do not necessarily follow in such an order, and therefore the research establishes likely paths in their development. Also, it appears that growth rate (relative to a market) and change in formalism are major factors distinguishing in the theory individual stages.</p><p><strong>Research Limitation/implication:</strong> Organizational life cycle theory is often neglected based on simplifying presumptions like determinism of organizational development. On the other hand, there is a growing evidence that factors stemming from particular life cycle stages alter organizational behavior and therefore should be considered in behavioral research on an organizational level.</p><p><strong>Originality/Value of paper:</strong> The paper represents up to date review of major theoretical models from the perspective of the current state of the field. Since the theory flourished in 70’s and 80’s it is inevitably limited in some aspects. The new review may spark renewed interest in implications stemming from the theory and enrich analytical tools of management scholars.</p>

The aims of this study were to determine the concentrations of calcium, magnesium, phosphorus, chlorine, potassium, sodium, urea, total cholesterol, triacylglycerols, non-esterified fatty acids, total protein, creatinine, total bilirubin, aspartate aminotransferase, insulin, insulin growth factor 1, and glucose in the blood serum and to monitor the body weight changes in nine clinically healthy Lipizzan mares at weekly intervals within 2 weeks before and 2 weeks after the parturition. A significant body weight loss (P < 0.01) was found in the mares after the foaling. The peak of insulin growth factor 1 concentration in serum was reached at the day of parturition and similar patterns were revealed for the concentrations of insulin and glucose. After parturition, all these indices were significantly decreased. The concentrations of phosphorus and triacylglycerols were decreased, while the concentrations of potassium and sodium were increased at the day of parturition. Moreover, the concentration of non-esterified fatty acids was increased at the day of parturition (P < 0.05) with a tendency to higher values even on the 7 th day postpartum. Other studied indexes remained relatively stable throughout the transition period. We can conclude that periparturient mares face some degree of negative energy balance with concomitant significant homeostatic and homeorhetic changes. For this reason, our results can be used as a basis for reference values and a diagnostic tool to examine the health status in horses during the transition period. Horse, metabolic indices, transition phase, homeostatic changes, homeorhetic changesThe peripartal period is a very challenging interval of life of dams due to the decreased feed intake in the late gestation that is accompanied by the increasing metabolic demands of the foetus, and then after the parturition due to the onset of milk production to cover the nutritional requirements of the offspring as well as for the postpartum (p.p.) recovery of the dam. It is well understood mostly from research performed on high-yielding animals, that all these events trigger different cascades of metabolic reactions as a part of the adaptation mechanisms of the organism of the dam concomitant to the transition from the pregnant non-lactating state to the non-pregnant lactating state. From the physiological point of view, the endocrine changes in mares around the parturition have been well described but only limited literature data are available in the field of biochemistry. It is known that especially during the transition period, both pregnant and lactating mares are highly vulnerable to various health disorders which could lead to different productive and reproductive problems (Reed et al. 2010). For this reason, it is recommended to perform a set of metabolic blood tests in dams over the transition to determine the dynamics of homeostatic and homeorhetic changes, and thus predict the course of puerperium in these animals. In general, the assessment of energy balance (non-esterified fatty ac...

Summary. The actions of insulin, prolactin and cortisol on protein, lipid and casein syntheses were examined in goat mammary explants in culture. The synthesis of the three products was stimulated by insulin and prolactin associated or not with cortisol. Casein synthesis was stimulated only when prolactin was present in the culture medium. Prolactin alone was able to significantly support the induction of casein synthesis. After preculture in the presence of insulin alone, the tissue lost part of its capacity to respond to the prolactin stimulus but, when precultured in the presence of insulin + cortisol, it retained its total sensitivity. These data suggest that insulin, prolactin and cortisol are involved in the maintenance of goat mammary tissue in culture but that prolactin essentially stimulates milk synthesis.Introduction.

Goat placental lactogen was partially purified from a medium collected after placental tissue incubation. The data obtained by disc electrophoresis and isoelectric focusing experiments, as well as by means of radioreceptor assay methods, provide evidence of the similarity between the goat and ovine placental lactogen.