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21.
SUMMARY: Two different reciprocal translocations, rcp (8;14) (p21;q25) and rcp (7;13) (q13;q46), were described for the first time in Poland in the Polish Landrace and Duroc pigs. Observation of synaptonemal complexes showed the presence of a quadrivalent composed of translocational chromosomes and their homologues. Individuals carrying translocations were characterized by normal external appearance and correct semen parameters. Analysis of fertility made on the basis of litter size demonstrated that fertility decreased by 25% in the carrier of translocation rcp (8;14) and by 52% in the carrier of translocation rcp (7;13). ZUSAMMENFASSUNG: Zum erste mal festgestelte gegenseitige Translokationen bei Schweine in Polen Bein Polnischen Landras und Duroc Schweinen wurden zum erstenmal in Polen, zwei verschiedene reciproke Translokationen-rcp (8;14) (p21;q25) und rcp (7;13) (q13;q46)-festgestellt. Anhand der Beobachtungen des Synaptonemal Complex wurde die Anwesenheit eines Tetravalent nachgewiesen, welches aus Translokationschromosomen und seinen Homologen zusammengesetzt ist. Die Translokationstiere hatten normale Exterieur und Spermaparameter. Aufgrund der Fortpflanzungsergebmissen wurden verminderte Fruchtbarkeit bei Translokationstieren rcp (8;14)-um 25% und bei Translokationstieren rcp (7;13)-um 52% festgestellt. RéSUMé: Les translocations réciproques identifiées pour la prèmière fois chez les porcs levés en Pologne Chez les porcs des races Landrace et Duroc on a constaté, pour la première fois en Pologne deux translocations réciproques différentes-rcp (8;14) (p21;q25) ainsi que rcp (7;13) (q13;q46). L'observation des complexes synaptonémals a manifesté la présence du quadrivalent composé de chromosomes de translocation et de leurs homologes. Les animaux-les porteurs de la translocation ont se caractérisé par l'extérieur normal et par les paramètres réguliers du sperme. L'analyse de la fertilité expérimenté selon de la taille des portées a démontré la réduction de la fertilité pour le porteur de la translocation rcp (8;14) à 25% cependant pour les porteurs de la translocation rcp (7;13) à 52%.  相似文献   
22.
Foliage of Afzelia africana, Pterocarpus erinaceus and Khaya senegalensis, from 10 trees per species, was collected every two weeks during the late dry, rainy and cool season to determine the seasonal effects on chemical composition. Fifteen rams of the Djallonké breed, weighing on average 20.0 kg, were used to evaluate the voluntary intake and digestibility of hay of A. gayanus, foliage of A. africana (as a sole feed), and A. africana, P. erinaceus and K. senegalensis offered with 30% of the diet as A. gayanus hay. The crude protein (CP) content of A. africana, and P. erinaceus decreased significantly from the late dry season to the cool season when that of K. senegalensis tended to increase. The mean CP of A. africana, P. erinaceus and K. senegalensis differed significantly (173 g, 139 g and 114 g/kg DM, respectively). The DM intake of A. africana offered with hay (571 g/d) or as a sole feed (598 g/d) were not significantly different, but was higher than that of P. erinaceus (428 g/d) and K. senegalensis (298 g/d). The digestibility calculated by difference of DM and CP of A. africana (582 g/kg DM and 795 g/kg CP, respectively) did not differ significantly from A. africana as a sole feed, but were higher than for the other species. The nutritive value of A. africana seems to justify the high preference of herders for this species.  相似文献   
23.
A cross-sectional survey was conducted in Sudan to determine sero-prevalence and risk factors associated with Neospora caninum infection in non-vaccinated dairy herds and to assess importance of the disease. Blood samples were collected from a total of 262 animals from 25 herds. Sera were tested for antibodies against N. caninum using ELISA test. The prevalence rates of N. caninum antibodies in cattle were high both at herd level (44%) and at individual animal level (10.7%). Herd level infection rates were similar in Khartoum State (43.7%) and at Gazira States (44.4%). The overall prevalence rates were higher (16.1%) in Gazira State than in Khartoum State (9%) but with no significant variation. The sero-prevalence at individual animal level was significantly higher (p < 0.05) in animals with history of abortion (12.8%) than in apparently healthy animal (11.3%), animal with history of infertility (8.1%), or neonatal death of calves (4.3%). In addition, significantly higher (P < 0.05) sero-prevalence was observed in samples collected during the rainy season (6.87%) than winter (3.05%) or summer (0.76%). However, no significant differences in sero-prevalence due to locality, animal breed, sex, and age were observed (p > 0.05). This preliminary study reveals for the first time the existence of natural N. caninum infection in Sudan. Also, the findings of the present study indicated that this disease is highly prevalent in two major areas of dairy production in the country, and this calls for control strategy to be implemented.  相似文献   
24.
The lack of protective action of oestrogens which appears during menopausal period may be the reason of serious metabolic disturbances including oxidative stress. The hypothesis was stated that ovariectomy may induce the variations of antioxidant/oxidant status which can be detected in rat liver. A total of 102 healthy Wistar female rats were included in the experiment and divided into control (CON; n = 6), sham-operated (SHO; n = 48) and ovariectomized (OVX; n = 48) groups. Animals from SHO (n = 6) and OVX (n = 6) groups were killed every week during 8 weeks of experiment to detect dynamic changes in examined parameters. Anti-oxidative enzyme activities [glutathione peroxidase (GSH-Px); superoxide dismutase (SOD)] as well as total antioxidant capacity (TAC) and the intensity of lipid peroxidation, measured by the concentration of N,N,diethyl-p-phenylene diamine (DEPPD) radical, were determined in liver homogenates by the use of spectrophotometric methods. Wave-like patterns of examined parameters within 8 weeks of experiment were detected. GSH-Px activity tended to be higher in OVX animals and was significantly lower at 8th week when compared with 1st week of experiment. SOD activity was higher in SHO animals and showed significant differences between 3rd, 4th, 7th and 1st week. TAC values were significantly higher in OVX when compared with SHO groups in 2nd, 4th, 5th week and significantly lower in 3rd, 6th and 7th week of the experiment. The concentration of DEPPD radicals tended to increase in OVX group. In conclusion, ovariectomy which leads to oestrogen insufficiency is reflected as well in variation of anti-oxidative/oxidative parameters in rat liver homogenates.  相似文献   
25.
Ectoparasites are the major causes of skin lesions in animals. Clinical, skin scraping examination, and histopathological studies were conducted to identify and characterize skin lesions in small ruminants caused by ectoparasites. Mange mites, lice, sheep keds, and ticks were collected from the skin of affected animals for species identification. Skin biopsies were collected from affected part of the skin and fixed in 10% neutral buffered formalin for histopathology. Of 1,000 sheep and 600 goats examined, 815 (81.50%) sheep and 327 (54.5%) goats were infested with one or more types of ectoparasites. Sarcoptes scabiei var ovis, Demodex ovis, Psoroptes ovis, Bovicola ovis, Melophagus ovinus, and Amblyomma variegatum and other tick species were identified from sheep. S. scabiei var caprae, Demodex caprae, Linognathus stenopsis, and A. variegatum and other tick species were identified from goats. Gross skin lesions or defects observed on the skin include stained and ragged wool, loss of wool/hair, nodules, crusts, lichenification, and fissuring. Microscopic evaluation of H and E stained skin sections revealed lesions in the epidermal layer such as hyperkeratosis, acanthosis, and melanin inconsistency on the basal cells of the epidermis. Follicular keratosis, perifolliculitis, frunculosis, perivasculitis, and aggregates of inflammatory cells (of acute and chronic type) with fibrosis were experiential in the dermal layer of the skin. Most of the skin lesions caused by ectoparasites are overlapping. Thus, ectoparasites control program should be executed to reduce skin lesions as skins are the major export commodity of the country.  相似文献   
26.
Biological response modifiers (BRM) are compounds that interact with the immune system to regulate specific aspects of host response. The objective of this study was to describe clinical and morphological changes during involution of bovine mammary gland following a single-dose infusion of a BRM containing lipopolysaccharide and cellular fractions of Escherichia coli incorporated into liposomes. A massive leukocyte response and increased subepithelial stroma infiltration of mononuclear cells, eosinophils and mast cells was observed in BRM-treated quarters compared with untreated controls; however, morphologic parameters assessed at 11 days post infusion were indicative of only slightly accelerated involution compared with untreated controls. In addition, BRM infusion at the end of lactation did not interfere with mammary epithelial cell proliferation and caused only mild systemic effects.  相似文献   
27.
It is common knowledge that fish are a nutritious component of a human diet, as they constitute a valuable and desired source of protein and polyunsaturated fatty acids. However, they are likely to pose a risk to consumer health. The presence of pathogenic bacteria or their toxins, parasites, biogenic amines and toxins or chemical residues may be a causal agent of foodborne illnesses in humans, sometimes even with fatal effect. Usually, infections are a result of insufficient thermal treatment or consumption of raw fish dishes. There are also risk factors that cannot be eliminated by such treatments as cooking, salting or freezing.  相似文献   
28.
The aim of the present study was to establish the effect of intravesical administration of resiniferatoxin (RTX) and tetrodotoxin (TTX) on the chemical coding of paracervical ganglion (PCG) neurons supplying the urinary bladder in the pig. In order to identify the PCG neurons innervating the bladder, retrograde tracer Fast Blue was injected into the bladder wall prior to intravesical RTX or TTX administration. Consequent application of immunocytochemical methods revealed that in the control group 76.82% of Fast Blue positive PCG neurons contain nitric oxide synthetase (nNOS), and 66.92% contain acetylcholine transferase (ChAT). Intravesical infusion of RTX resulted in a reduction of the nNOS-IR neurons to 57.74% and ChAT-IR to 57.05%. Alternative administration of TTX induced an increase of nNOS-IR neurons up to 79.29% and a reduction of the ChAT-IR population down to 3.73% of the Fast Blue positive PCG cells. Our data show that both neurotoxins affect the chemical coding of PCG cells supplying the porcine urinary bladder, but the effects of their action are different. Moreover, these results shed light on the possible involvement of NO-ergic and cholinergic neurons in the mechanisms of therapeutic action exerted by RTX and TTX in curing the overactive bladder disorder.  相似文献   
29.
1. The aim of the study was to investigate the effects of feeding fast growing turkeys with differentiated dietary calcium (Ca) content, and the partial replacement of vitamin D3 in the feed with 25-hydroxycholecalciferol (25(OH)D3), on skeletal properties.

2. One-day-old Big-6 male turkeys (n?=?1008) were randomly divided into 4 groups, and two subgroups were created within each group. The groups were differentiated with 4 levels of Ca provision in the feed, namely 85% of the National Research Council (NRC) recommendation (Group Ca1); 95% as above (Group Ca2); 105% as above (Group Ca3); and 115% as above (Group Ca4). The first subgroup received the recommended dosage of cholecalciferol (vitamin D3 subgroup) in the feed, while in the second subgroup (Hy-D subgroup), half of the dosage of cholecalciferol was replaced with 25(OH)D3. At the ages of 4, 8, 12 and 20 weeks, 7 turkeys from each subgroup were randomly selected and killed to obtain the right tibia for densitometric, geometric and mechanical analyses.

3. This study showed advantageous effects of increased calcium supply in the diet on skeletal system properties, that were increased and produced the most desirable traits in turkeys receiving 95%, 105% and 115% of the NRC calcium recommendation. Benefits resulting from administration of 25(OH)D3 in the diet were also obtained in the skeletal formation of turkeys, and the most advantageous effects were present in the group receiving 105% of recommended dietary Ca.

4. Effects on the metabolic response of the skeleton of turkeys to manipulation of dietary calcium content and vitamin D3 source were the most evident in the groups between 4 and 12 weeks of life, and demonstrated a limited ability to induce a positive influence on bone properties at advanced stages of the production cycle by alteration of these dietary factors.  相似文献   

30.
Understanding the utilisation patterns of milk assists in designing appropriate dairy development schemes in rural communities. The objective of the study was to determine milk utilisation patterns in different smallholder farming systems in the Eastern Cape Province of South Africa. Data were collected through the administration of recording sheets to 130 randomly selected households in Alice, Fort Beaufort and Queenstown districts. Amounts of milk produced per household ranged from 9 to 21 l per household per day. Milk consumption/household/day was similar among the three districts. Milk consumption in the early lactation doubled the amount consumed in late lactation (P < 0.05). Milk in the communal areas was largely utilised as fresh or sour milk. Fresh milk was mostly used in tea/coffee or to make porridge for children. Sour milk was consumed with thick boiled maize meal. Fort Beaufort (10.2 ± 1.37 l/day) had the highest sour milk sales whilst Queenstown had the highest fresh milk sales (9.7 ± 5.57 l/day). It was concluded that quantities of milk consumed or sold as fresh or sour were generally low and varied across smallholder farming systems.  相似文献   
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