Forced locomotor activity improves walking ability of male turkeys and modifies carcass characteristics

1. This trial investigated the effect of forced locomotor activity (training) on walking ability, leg posture, and growth performance, as well as carcass composition and meat quality in male fattening turkeys.2. A flock of 744 commercial turkeys was divided into three experimental groups, either without any training period (control), training from weeks 2 to 8 (short-term), or training from weeks 2 to 21 (long-term). All birds were slaughtered at an age of 21 weeks. To study the effect of short vs. long time lapse between shackling and stunning (suspension time), each training group was split into two halves that were hooked on the shackle for either 15 s or 3 min prior to stunning.3. Long-term physical training, compared to short-term or no training, resulted in better walking ability and in a lower percentage of leg malposition, as assessed at the end of fattening. No effect on final body weight was detected.4. In a subsample, the composition of 80 carcasses was determined by dissection. Long-term training favoured the percentage of the drumstick over that of the breast cut in comparison to the group without any training.5. Meat quality parameters were determined for breast muscle. The pH values 20 min post-mortem were reduced by long-term training, and the highest value was observed for a combination of no training with short suspension. After 24 h, pH values did not differ between experimental groups. The breast muscles were characterised as fast-glycolysing. Prolonged suspension time resulted in higher electrical conductivity after 24 h, and in higher a* values (redness).6. In conclusion, the study revealed that a long-term training period improved walking ability and leg posture of heavy male turkeys. Thus, training can contribute to the improvement of animal welfare in turkey husbandry. Meat quality variables of breast muscles were partially influenced by locomotor activity and suspension time.

POMT1-associated walker-warburg syndrome: a disorder of dendritic development of neocortical neurons

We have analyzed the morphology and dendritic development of neocortical neurons in a 2.5-month-old infant with Walker-Warburg syndrome homozygotic for a novel POMT1 gene mutation, by Golgi methods. We found that pyramidal neurons frequently displayed abnormal (oblique, horizontal, or inverted) orientation. A novel finding of this study is that members of the same population of pyramidal neurons display different stages of development of their dendritic arborizations: some neurons had poorly developed dendrites and thus resembled pyramidal neurons of the late fetal cortex; for some neurons, the level of differentiation corresponded to that in the newborn cortex; finally, some neurons had quite elaborate dendritic trees as expected for the cortex of 2.5-month-old infant. In addition, apical dendrites of many pyramidal neurons were conspiciously bent to one side, irrespective to the general orientation of the pyramidal neuron. These findings suggest that Walker-Warburg lissencephaly is characterized by two hitherto unnoticed pathogenetic changes in the cerebral cortex: (a) heterochronic decoupling of dendritic maturation within the same neuronal population (with some members significantly lagging behind the normal maturational schedule) and (b) anisotropically distorted shaping of dendritic trees, probably caused by patchy displacement of molecular guidance cues for dendrites in the malformed cortex.

Schlachtkörperzusammensetzung und Gewebebeschaffenheit von schweren Schweinen – II. Mitteilung: Merkmale der Fleisch- und Fettqualität

Abstract. Title of the paper: Carcass and meat quality of heavy pigs. II. Characteristics of meat and fat quality The aim of the 2nd part of the study was to present the shifts concerning the meat quality in various important muscles and the fatty acid profile in the backfat associated with a prolonged fattening. In total, 63 male castrates and 60 females (Piétrain-NN*German Landrace) were randomized to three groups with different live weights at slaughter (110, 135, 160 kg). The pH values, measured at different points in time, were not influenced by the live weight class. However, electrical conductivity as well as drip loss traits of the M. longissimus dorsi increased slightly in the upper weight class, whereas the cooking loss declined marginally. With increasing live weight there was in general a small tendency to a darker meat and a clear enhancement of the a* values, based upon higher pigment concentrations. Moreover, the water content diminished slightly, whereas the intramuscular fat content did not rise significantly within the same sex. Compared with 110 kg live weight, the collagen content and the percentage of soluble collagen decreased at 160 kg live weight whereas shear force values remained unaffected. In the sensory evaluation, pork chops of the 135 kg class received numerically the best and those of the 160 kg the worst ratings, but the differences were small and only exceptionally significant. Considering the fatty acid profile in the course of a prolonged fattening, there is a shift to smaller proportion of polyenic fatty acids in favour of oleic and palmitic acid.

Schlachtkörperzusammensetzung und Gewebebeschaffenheit von schweren Schweinen – I. Mitteilung: Material und Methoden, Mastleistung, Schlachtkörperzusammensetzung und Teilstückanteile

Abstract. Title of the paper: Carcass and meat quality of heavy pigs. I. Experimental design, methods, fattening performance, carcass composition and proportion of cuts The aim of the 1st part of the study was to present the shifts concerning carcass composition and proportion of cuts associated with a prolonged fattening. In total 63 male castrates and 60 females (Piétrain-NN *German Landrace) were randomized to three groups with different live weights at slaughter (110, 135, 160 kg). The increase of live weight to 135 and 160 kg, respectively, took on average 28 and 55 days. Compared with the lower weight class (110 kg) the daily gain calculated with respect to the whole fattening period decreased only by 30 g/d. The feed efficiency, however, increased from 2.7 to 3.1 kg feed / kg weight gain. The M. longissimus area of castrates and gilts, respectively, rose from 53 to 68 cm2 and from 58 to 73 cm2, respectively, while the lean meat content decreased from 57 to 54 % and from 61 to 57 %, respectively. The weight gain of the loin and the neck amounted absolute to 2.4 and 1.3 kg, respectively. The relative weight gain of the backfat and those cuts rich in adipose tissue (e.g. chump, ventral parts of the belly), amounted to 84 % and 60–70 %, respectively, whereas the primal cuts with a high lean content (ham, loin, shoulder, neck) gained only by 40 to 45 %.

Nitrinergic neurons in the developing and adult human telencephalon: transient and permanent patterns of expression in comparison to other mammals

A subpopulation of cerebral cortical neurons constitutively express nitric oxide synthase (NOS) and, upon demand, produce a novel messenger molecule nitric oxide (NO) with a variety of proposed roles in the developing, adult, and diseased brain. With respect to the intensity of their histochemical (NADPH-diaphorase histochemistry) and immunocytochemical (nNOS and eNOS immunocytochemistry) staining, these nitrinergic neurons are generally divided in type I and type II cells. Type I cells are usually large, intensely stained interneurons, scattered throughout all cortical layers; they frequently co-express GABA, neuropeptide Y, and somatostatin, but rarely contain calcium-binding proteins. Type II cells are small and lightly to moderately stained, about 20-fold more numerous than type I cells, located exclusively in supragranular layers, and found almost exclusively in the primate and human brain. In the developing cerebral cortex, nitrinergic neurons are among the earliest differentiating neurons, mostly because the dominant population of prenatal nitrinergic neurons are specific fetal subplate and Cajal-Retzius cells, which are the earliest generated neurons of the cortical anlage. However, at least in the human brain, a subpopulation of principal (pyramidal) cortical neurons transiently express NOS proteins in a regionally specific manner. In fact, transient overexpression of NOS-activity is a well-documented phenomenon in the developing mammalian cerebral cortex, suggesting that nitric oxide plays a significant role in the establishment and refinement of the cortical synaptic circuitry. Nitrinergic neurons are also present in human fetal basal forebrain and basal ganglia from 15 weeks of gestation onwards, thus being among the first chemically differentiated neurons within these brain regions. Finally, a subpopulation of human dorsal pallidal neurons transiently express NADPH-diaphorase activity during midgestation.

Transient patterns of organization of the human fetal brain

Fetal development of the human brain is characterized by continuous transformations and reorganization of the fetal telencephalic wall which consists of transient, cytoarchitectonically defined cellular compartments, the so-called embryonic/fetal zones. The cellular and fiber content of these zones is permanently changing, so that fetal neuronal circuitry elements (afferent fibers, synapses, and postsynaptic neurons) display transient patterns of areal, laminar, and modular organization. In the late human fetus and preterm infant, transient patterns of structural and physiological organization form the basis of transient behavioral states and patterns of activity. The transient subplate zone is a key compartment for transient fetal neuronal circuitry, and competitive cellular interactions within the subplate zone are crucial for the areal specification of the cerebral cortex and the formation of cortical connectivity. The subplate zone may also have a key role in cortical repair and plasticity after perinatal brain lesions.

Transformation of the shape of the ethmoid bone during the course of life

The ethmoid bone undergoes significant changes in the course of life. The critical period is the time from 9 to 35 years of age. The changes in its shape depend upon the intensity of pneumatization of the ethmoid labyrinth and frontal sinus. If pneumatization of the labyrinth is excessive, the ethmoidal cells are not covered by the frontal bone. On the contrary, they are incorporated in the inferior floor of the anterior cranial fossa, resulting in a possible risk of penetration during surgical ethmoidectomy.

Anti-GM3 (II3Neu5Ac-lactosylceramide) ganglioside antibody labels human fetal Purkinje neurons during the critical stage of cerebellar development

The ganglioside GM3 (II3Neu5Ac-lactosylceramide) represents a minor ganglioside in normal human brain compared to major gangliosides with gangliotetraose-backbone. In this study the presence of GM3 in three 23 and 24 weeks of gestation old human cerebella was demonstrated by immunostaining extracted gangliosides on thin-layer chromatography plate as well as by immunohistochemical analysis of cerebellar cryosections. During this stage of brain development GM3 was found to be dominantly expressed on cells corresponding to Purkinje neurons. Delipidation of histological sections with chloroform/methanol caused significant reduction of anti-GM3 immunostaining, thus confirming the prevalent ganglioside nature of this antigen. These results give evidence that (1) GM3 ganglioside is associated with a specific subset of human fetal cerebellar neurons during the critical development stage, and (2) a definite ganglioside in general is distributed to a specific subset of cells in normal human brain.

Ontogenesis of goal-directed behavior: anatomo-functional considerations

Recent neuroanatomical and neurophysiological studies in man have revealed ontogenetic events which coincide with broadly defined phases of behavioral and cognitive development. During the early fetal period, early produced neurons make initial synapses which form the basis for the earliest electrical activity of the human brain. The overall immaturity of neuronal connections, in particularly in cortical areas, correlates with the absence of any behavioral pattern or goal-directed movements. In the late fetus and preterm infant, transient accumulation of major afferent pathways, the presence of transient layers (subplate zone) and transient pattern of transmitter-related organization form the neurological basis of cortical electric responses as well as transient behavioral states and sleep patterns. Parallel to the profound structural and chemical reorganization of the human cerebrum during the first 6 postnatal months there is a disappearance of transient behavioral and motor patterns. The previously close spatio-temporal correlation between these events becomes progressively looser. The overproduction of circuitry elements during the subsequent period peaks in associative cortex between 1 and 2 years of age, corresponding to the emergence of skilled actions and cognitive functions. After the elimination of some circuitry elements after the second year of life, the prolonged maturation of goal-directed behavior and the protracted emergence of different cognitive functions correlates with the development plateau of synapse production which can be seen up to 16 years of age. Parallel to the prolonged maturation of postsynaptic elements, there are well defined maturational changes in the chemical properties of associative pyramidal neurons of cortical layer III. These findings correspond to the prolonged maturation of movement-related brain macropotentials as well as other cognition-related potentials, where the last prominent changes were seen after 10 years of age. Although the coincidence of the developmental events does not necessarily mean a causal relationship, the combination of structural and physiological data opens new vistas for the further investigation of the neurobiological basis of goal-directed movement and cognitive behavior.

Identification of war victims in Croatia

The intention of this paper is to describe the organizational principles and indicate the results already achieved in the identification of war victims in Croatia. By 25 February 1993, 6,493 victims had been identified. A model is proposed that could be used in the course of identification processes, examining the methods and principles of identification which have been complicated by the time interval of more than a year from the time of death, for a presumed number of several thousand (up to 14,000) unidentified victims, possibly in mass graves. Identification is further complicated by the lack of ante-mortem medical and dental records and the incapacity to utilize more expensive methods of identification. Attention is drawn to a group of more complex cases examined at the Institute of Forensic Medicine and Criminology.

Early areal differentiation of the human cerebral cortex: entorhinal area

The early cytoarchitectonic specialization and area-specific differentiation of the prospective entorhinal cortex were studied in the postmortem human fetal brains (9.5-13.5 postovulatory weeks). At 10 weeks, using the Golgi method, we saw the appearance of area-specific large neurons (promoter neurons) with widely bifurcating apical dendrites situated at the outer margin of the cortical plate of the prospective entorhinal cortex. The analysis of the serial Nissl-stained sections revealed the concomitant appearance of a one-cell-thick layer (monolayer) at the interface between the cortical plate and the marginal zone and multilaminated spread of the deep part of the cortical plate. This is the earliest sign of area-specific cytoarchitectonic differentiation of all pallial regions characterized by the presence of the typical cortical plate. The first subareal differentiation within the entorhinal cortex begins at 13 postovulatory weeks with uneven development of fiber-rich lamina dissecans, which separates two cellular laminae principals (externa and interna), and with the appearance of characteristic cell islands of the prospective layer II. At rostral levels, cell islands begin to develop in the rostromedial entorhinal area at the subpial depths where large promoter neurons reside. At intermediate levels, both lamina dissecans and lamina principalis interna are well delineated. At caudal levels, lamina principalis interna is continuous with the upper subplate zone of the adjacent neocortex. Both area-specific neurons (promoters) and fiber-rich (afferent) strata develop synchronously during the earliest areal differentiation of the cerebral cortex. The precocious lamination of the cortical plate is the crucial event in the histogenesis of the entorhinal cortex.

Zagreb research collection of human brains for developmental neurobiologists and clinical neuroscientists

The aim of this paper was to offer for the first time a selective and systematic description of the "Zabreb Neuroembryological Collection" of human brains and to illustrate the major results of our research team. Throughout these 16 years of continuous and systematic research, we have applied different techniques for demonstrating the cytoarchitectonics (Nissl staining), neuronal morphology (Golgi impregnation), synaptogenesis (EM analysis), growing pathways (acetylcholinesterase histochemistry) and transmitter-related properties of developing neuronal populations (immunocytochemistry and acetylcholinesterase histochemistry) on several hundred human brains ranging in age from the 5th week post-conception to 90 years. The combination of classical and modern research techniques applied to the constantly growing developmental collection, as well as the continuous evaluation of our data in the light of experimental work in non-human primates, has led to the discovery of an early synaptogenesis within the human cortical anlage and hitherto undescribed transient subplate zone; our results also provided the first comprehensive evidence concerning the timing and pattern of development of afferent fiber systems in the human cortex. All this enabled us to offer a well-documented and coherent reconstruction of major histogenetic events in the human brain. We concluded that structural remodeling and reorganization of the brain, from the transient patterns of the fetal organization through the postnatal phase of transient overproduction of circuitry elements to the final maturation, is the crucial principle of development. Fetal neuronal elements (afferents, synapses and postsynaptic neurons) display transient patterns of laminar, vertical and modular organization and transient cellular interactions and competition in the subplate zone are crucial for the formation of cortical connections. The elucidation of the nature and timing of these histogenetic reorganizational events in the human brain represents the first step towards determining the neurobiological basis of the emergence of behavior, neural functions and cognition in human fetuses, infants and children, which takes place during perinatal and early postnatal life.

Neuroscience in Yugoslavia

This survey is a personal account of the present status of neuroscience in Yugoslavia within the context of recent upheavals in Eastern Europe. The current situation in Yugoslavia, characterized by the absence of a Federal Ministry of Science and a poor scientific communication between federal states (republics), does not allow a comprehensive overview of neuroscience at the federal level. Even more difficult is to envisage the prospects of Yugoslav neuroscience in the light of European integration. Several problems serve to illustrate the present situation concerning Yugoslav neuroscience. First, the weakness of the self-organization of science in Yugoslavia during the past 20 years is still the most important denominator in the current trend of neuroscience. Second, different Yugoslav republics have significantly different systems of science funding and evaluation, which reflect very plainly different levels of democratic (and socioeconomic) changes that were attained during 1990. Third, due to the different numbers of trained scientists, facilities and equipment, funds and levels of international scientific cooperation there are major differences between republics in the tempo of progress towards real achievements in science. Finally, the present explosive development of neuroscience and the proclamation of the 'Decade of the Brain' will hopefully stimulate Yugoslav neuroscientists to seek better programmes of neuroscience research and to improve the extent and quality of international cooperation.

Structural basis of the developmental plasticity in the human cerebral cortex: the role of the transient subplate zone

We correlated neuroanatomical developmental parameters with sequential ultrasonography scans to reveal the structural basis of functional recovery after early focal hypoxic lesions of the human frontal lobe in premature infants. We studied the transient fetal subplate zone in the premotor and prefrontal cortex in premature, newborn, infant, and young adult brains by acetylcholinesterase (AChE) histochemical, Golgi, and immunocytochemical methods. The structural in vivo rearrangements of the cerebral wall after perinatal lesions were studied on serial real-time sector scans (5-MHz transducer). The subplate zone contains "waiting" axons and randomly oriented fetal neurons, its developmental peak is between 22 and 34 weeks of gestation, and it is present in the frontal cortex of newborns and disappears after the sixth postnatal month, but individual subplate-like neurons remain until adulthood. Ultrasonography revealed remarkable structural rearrangements of the cerebral wall when the hypoxic lesion occurred during the developmental peak of the subplate zone: anechoic cavities ("cysts") develop rapidly (within 3 weeks) in premature brains, the rebuilding of these lesions continues after birth, and cavities disappear around the 11th month. We propose that the transient population of "waiting" axons and cells of the subplate zone participate in the structural and functional plasticity of the human cerebral cortex after perinatal brain damage.

Early onset of synapse formation in the human hippocampus: a correlation with Nissl-Golgi architectonics in 15- and 16.5-week-old fetuses

The developmental status of some potential components of hippocampal circuitry was studied at the time of the emergence of the hippocampal cytoarchitectonic subfields. The laminar distribution of synapses as seen with electron microscopy was correlated with Golgi architectonics in 15- and 16.5-week-old human fetuses. A systematic electron microscopic analysis of the distribution of synapses demonstrated that they were restricted to the two zones bordering the cortical plate, viz. the marginal and subplate zones, which contain dendritic branches of pyramidal and large polymorphous non-pyramidal neurons. The density of synapses (number per unit area) was higher in the marginal zone than in the subplate zone. Most synapses were of the asymmetric axodendritic type, although some were symmetric axodendritic synapses. The possible origins of the axons forming these synapses are discussed. This study demonstrates that the human hippocampus shows an early onset of synapse formation, with a characteristic distribution of synapses in restricted laminae. The finding of early synapse formation is consistent with observations made in other cortical areas during development. The prevalence of synaptogenesis at a superficial level of the cortex seems, however, to be specific to the "archicortex".

Cytoarchitectonic parameters of developmental capacity of the human associative auditory cortex during postnatal life

In order to determine the developmental capacity of the human auditory cortex we studied the 'regressive' cytoarchitectonic events during perinatal and postnatal development: disappearance of fetal elements and cytoarchitectonic reorganization. Studies were done on Nissl-stained serial sections of human temporal cortex in the specimens ranging from 24 weeks of gestation to the 3rd postnatal year. The fetal layers were regularly found in the newborn in the posterior associative auditory cortex. The fetal subplate zone disappeared gradually over the first 3 postnatal months, indicating decline in the growth of the major cortical fibre systems. The fetal types of neurons have been found however also in older specimens in the associative auditory cortex. The auditory cortex also contains in the postnatal period some fetal elements which indicate the presence of prolonged anatomical developmental plasticity.