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51.
52.
Dissolved gas supersaturation is hazardous to fish and can result in gas bubble disease (GBD). Signs of GBD typically include bubbles in the eyes, fins, skin, lateral line, and gill filaments. Ocular abnormalities in diseased salmonids typically occur after aberrant gas production in the eyes. In this study, freshwater rainbow trout Oncorhynchus mykiss were exposed experimentally to percent total gas pressure (TGP%) levels of 104% (control) and 115%. No mortalities occurred during the 7-d experimental period. Effects of GBD were observed externally as a darkened skin, exophthalmia, localized hemorrhage in the eye, and gas bubbles on the operculum. Additional signs included increased swimming activity and, more frequently, panic episodes. Carbonic anhydrase (CA) enzyme activities from the lens and retina were determined at days 0, 1, 3, 5, and 7 of the study. Venous blood gases were also measured on day 7. Retinal pH did not differ between normal and affected fish, but blood characteristics such as the partial pressure of O2, partial pressure of CO2, carboxyhemoglobin level, and bicarbonate ion concentration were significantly elevated in affected fish relative to normal fish. Venous blood pH and oxyhemoglobin levels were not significantly different between affected and normal fish. Patterns of response to total dissolved gas levels differed between the lens and the retina. Mean CA activities in the lenses of fish exposed to a TGP% level of 115% were significantly below those of control fish. However, retinal CA activities did not significantly differ between the two groups over the course of the experiment. These findings show that dissolved gas supersaturation reduces CA activity in the rainbow trout lens.  相似文献   
53.
Five long-legged buzzards (Buteo rufinus), weighing 475-570 g, were used in this study. It was determined that long-legged buzzards' larynx is composed of three different cartilages. Among these cartilages, the cricoid and procricoid cartilages were single and the arytenoid cartilage was double. The partially ossified corpus and ala of the cricoid cartilage were connected with cartilaginous plate. Trachea was formed up of complete cartilage circles. The tracheal cartilages were notched in dorsal and ventral directions and a number of the tracheal cartilages inter-mingling one another were between 89-96. Syrinx, which was covered with the inter-clavicular air sac, was in contact with basis cordis. It was observed that there is tracheobronchial type syrinx in long-legged buzzard and this syrinx is formed by two different cartilage groups named as the cartt. tracheosyringeales and cartt. bronchosyringeales. The first cartilage rings of the cartt. tracheosyringeales formed the tympanum. The tympanum, cartt. tracheosyringeales and cartt. bronchosyringeales were created of three, two or three and four cartilage rings, respectively. Membrana tympaniformis lateralis and medialis, two pairs of thin membranes constituting voice formation, also determined in long-legged buzzard. Membrana tympaniformis lateralis was observed to be very short between the first and second cartilage rings of cartt. bronchosyringeales. Although the instrictic syringeal muscles were not present in long-legged buzzard, the sternotracheal and tracheolateral muscles, expressed as extrinsic syringeal muscles, were evident. In this study, which is expected to give contribution to veterinary anatomy literature, the similarities and differences in larynx, trachea and syrinx of long-legged buzzard with other bird species were exposed.  相似文献   
54.
1. The aim of the study was to describe the effect of Epigallocatechin-3-gallate (EGCG), a polyphenol derived from green tea, on activator protein-1 (AP-1) components (phospho-c-Jun and c-Fos), cyclooxygenase-2 (COX-2) and heat shock proteins (HSPs) in the liver of heat-stressed quails.

2. A total of 180 5-week-old female Japanese quails were reared either at 22°C for 24 h/d (thermoneutral, TN) or 34°C for 8 h/d (heat stress, HS) for 12 weeks. Birds in both environments were randomly given 1 of 3 diets: basal diet and basal diet with 200 or 400 mg of EGCG added per kilogram of diet.

3. The hepatic c-Jun, c-Fos, COX-2 and HSPs gene expression for quails reared under the HS environment was greater than those reared under the TN environment. Supplemental EGCG decreased hepatic expression of these proteins at a greater extent under HS than TN.

4. In conclusion, suppression of AP-1 COX-2 and HSPs may partly account for the inhibitory effect of EGCG in heat-stressed quail.  相似文献   

55.
The aim of this study was to determine models which will be used for the estimation of adult live weights based on some body measurements using multiple regression model in Karya sheep of different age groups. Animal material of the study consisted of a total of 215 Karya sheep. Least squares means for live weight, body length, rump height, withers height, back height, chest depth, chest girth, and chest width of Karya sheep in Adnan Menderes University Group Sheep Breeding Program elite flock and breeder flocks were found as 47.24 kg, 67.08, 68.29, 68.58, 66.97, 30.04, 93.24, and 18.29 cm, respectively. Karya ewes were put into five categories according to ages (2–6 years). High positive phenotypic correlation coefficients were observed between live weight and body measurements of animals in different age groups (2–6 years). Among the formed multiple regression models, the highest coefficients of determination (R 2) were obtained from the models formed for body length or body length and chest girth together (R 2?=?0.79, R 2?=?0.87). It is concluded that live weight of Karya sheep can be estimated with a high accuracy using some body measurements and statistical methods.  相似文献   
56.
ABSTRACT

Rice ecosystems are currently impacted by numerous issues resulting in reduced returns from rice production. In order to sustainably increase rice yields, it is important to understand the soil quality of paddy fields. The aim of this study was to determine the quality of soil of the Çar?amba Deltaic Plain in Turkey for rice cultivation. For that purpose, the integrated Soil Quality Index (SQI) model, which is based on standard scoring functions and the weight assignment approach, was used. A total of 14 soil quality parameters, based on the key predictor variables for determining rice yield, were included in the SQI model by grouping them within three indicator classes, namely physical, chemical and nutrient element content. Soil samples were collected from 160 grid points in total in the study area which had been divided into 600 m × 600 m grid squares. Very high-quality soil was not detected in the study area. However, 36.1% of the soil was classified as high quality whereas 23.2% of the total area had low and very low soil quality for rice cultivation. The SQI model provides comprehensive guidance for land allocation for the cultivation of rice and potentially for other crops.  相似文献   
57.
The aim of this study was to determine the effects of the body condition score (BCS) of ewes before and during the mating season on their reproductive performance under an extensive production system. In this study, 240 Kivircik sheep from the flocks of two breeders were used for over a 2-year period. The flocks were fed under extensive conditions on natural pastures throughout the year. The ewes were synchronized in two different periods, one of which was 45 days before the other. Before the introduction of rams to the ewes, the ewes were weighed after measuring their BCS. Detailed records were kept for every flock in each year. We found significant effects of BCS on pregnancy rate, lambing rate (P < 0.05) and fecundity (P < 0.05). The BCS for the highest pregnancy, lambing rate, and fecundity was determined between 2.01 and 3.00, while the lowest rates for these traits were ≤1.50. The highest rates of the pregnancy rate, lambing rate, and fecundity and gestation productivity were 75.9%, 70.9%, 1.11 and 3.34 kg, respectively.  相似文献   
58.
59.
1. The effects of tomato powder supplementation on performance, egg quality, serum and egg yolk carotenoids, vitamins and malondialdehyde (MDA) concentrations in were investigated in laying hens in mid-lay.

2. A total of 90 laying hens, 49 weeks old, were divided into 3 groups consisting of 6 replicate cages, 5 birds per cage. Birds were randomly fed on one of three diets: basal diet and basal diet added with 5 or 10?g tomato powder per kg diet.

3. As tomato powder concentration increased, there were linear increases in feed intake, egg production, egg weight and yolk colour and a linear decrease in feed conversion. Shell weight, shell thickness and Haugh unit remained unchanged in response to dietary treatments.

4. Concentrations of serum and egg yolk lycopene, β-carotene, lutein and vitamin A increased for both diets including tomato powder, whereas MDA decreased linearly with increasing supplemental tomato powder concentration.

5. Tomato powder supplementation increased egg production persistency and increased carotenoids and vitamin A contents in egg yolk, accompanied by reduced yolk lipid peroxidation.  相似文献   
60.
A 12‐week feeding trial was conducted to estimate the effects of supplemented amino acids (lysine and methionine) with different dietary protein levels on growth, haematology and liver histology in meagre (Argyrosomus regius) at two different sizes: fingerling (15.2 g) and juvenile (44.4 g). Six practical diets were prepared, and three of these practical diets were formulated with 40 (P40), 44 (P44) and 48% (P48) crude protein without supplementation of amino acids. Other three diets having same protein levels were supplemented with lysine and methionine (P40AA, P44AA and P48AA) to bring these amino acids level up to that estimated to be at the least in the 48% protein diet. Final mean weight (FMW) and specific growth rate (SGR) of P48AA in fingerlings were higher than that of 40AA. According to FMW and SGR of juveniles, there was interaction found between dietary protein levels and the supplementation of amino acids. The FMW and SGR of meagre fed P44AA were higher than that of fish fed the other diets, except fish fed the P48. Economic profit index, packed cell volume and haemoglobin for juvenile meagre were significantly improved with the dietary protein level and amino acid supplementation. The liver tissues of the P48 group in both sizes displayed better structure compared with the other groups. In conclusion, dietary crude protein content of practical diets for juvenile meagre could be reduced from 48% to 44% by adding essential amino acids with an enhancement in growth, health and economic profit.  相似文献   
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