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941.
105 growing sows in the live weight range were fed with 7 test rations with graduated energy and amino acid levels. The growth intensity was very much influenced by the daily energy consumption. On the basis of regression analysis the following linear relation between daily weight increase (y in g per kg live weight0,75) and the daily energy consumption (x in energetic feed units for pigs per kg live weight0,75) was calculated: y = -13,79 + 0,7037 x (r = 0,84, sb -0,0295). The interpolation with regard to live weight balance resulted in a maintenance requirement of 19,8 energetic feed units for pigs resp. 70 kcal net energy fat for pigs per kg live weight0,75. The methods of assessment chosen showed an increase of the energy requirement per 100 g additional live weight increase per day of a constant amount, independent of the live weight, of 142 energetic feed units for pigs resp. 497 kcal net energy fat for pigs.  相似文献   
942.
A comparative study of the red cell characters, glycolytic enzymes and intermediates was made in the domestic dog and the dingo. No significant differences were found in any of the parameters studied except the enzyme level of NADH-MR which was significantly lower in dingoes (P less than 0.05).  相似文献   
943.
A test to detect antibodies to bovine syncytial virus was developed from the observation that syncytia in monolayer cell cultures infected with bovine syncytial virus regress and disappear in the presence of bovine syncytial virus antibodies. The test is useful in monitoring the presence of bovine syncytial virus and bovine syncytial virus antibodies in cattle used in studies on bovine leukosis.  相似文献   
944.
Distillers dried grains with solubles (DDGS) has low and variable AA digestibility. The variability is often attributed to damage during the heating process, and it has been suggested that the damage happens to the soluble components of DDGS such as reducing sugars. Combining solubles and grains sometimes produces syrup balls (SB); their digestibility is unknown. The objective of this experiment was to identify potential sources of poor and variable AA digestibility in DDGS. Specifically, our objective was to determine whether the problems are associated with the solubles component or with SB. The ingredients evaluated were DDGS, intact SB, ground SB, liquid condensed solubles (LCS), and pulse dried thin stillage (PDTS) obtained from the same ethanol plant. The LCS is produced by evaporation of thin stillage. Each ingredient was used as the only source of AA in an experimental diet. In a duplicate 6 × 6 Latin square design with 7-d adaptation and collection periods, the 6 treatments consisted of an N-free diet and the 5 test ingredients. Pigs had 5 d of adaptation to each diet, and on d 6 and 7 ileal digesta were collected from an ileal cannula for 8 h each day. Both SB treatments had apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of AA that were similar or greater (P < 0.05) than those of DDGS. The AID and SID values of Lys and a few other AA were similar in LCS (SID Lys: 63.1%) and DDGS (SID Lys: 61.5%), but the digestibility values of most AA in LCS were less than in DDGS (P < 0.05). The low digestibility of AA in LCS was most pronounced for Met (SID: LCS, 41.9% vs. DDGS, 82.8%). The LCS had less (P < 0.05) AID and SID of CP (SID: 67.8%) than intact SB (SID: 85.2%) and ground SB (SID: 85.9%) as well as all AA. The PDTS generally had the least AID and SID and had less (P < 0.05) CP (SID: 55.3%) and several AA, including Lys, compared with LCS. In conclusion, the presence of SB does not decrease AA digestibility of DDGS, and the LCS evaluated has less indispensible AA digestibility than DDGS. The LCS has low digestibility of AA that seems to not be caused by heat damage.  相似文献   
945.
No loss in the titre of infectious bovine rhinotracheitis virus was found during storage in semen at –196°C for 1 year.  相似文献   
946.
Infection with equine herpesvirus-1 (EHV-1) causes respiratory disease, late-term abortions and equine herpesvirus myeloencephalitis (EHM). Our understanding of EHM pathogenesis is limited except for the knowledge that EHV-1 infected, circulating peripheral blood mononuclear cells (PBMC) transport virus to the central nervous system vasculature causing endothelial cell infection leading to development of EHM. Our objective was to develop a model of CNS endothelial cell infection using EHV-1 infected, autologous PBMC. PBMCs, carotid artery and brain endothelial cells (EC) from 14 horses were harvested and grown to confluency. PBMC or ConA-stimulated PBMCs (ConA-PBMCs) were infected with EHV-1, and sedimented directly onto EC monolayers ('contact'), or placed in inserts on a porous membrane above the EC monolayer ('no contact'). Cells were cultured in medium with or without EHV-1 virus neutralizing antibody. Viral infection of ECs was detected by cytopathic effect. Both brain and carotid artery ECs became infected when cultured with EHV-1 infected PBMCs or ConA-PBMCs, either in direct contact or no contact: infection was higher in carotid artery than in brain ECs, and when using ConA-PBMCs compared to PBMCs. Virus neutralizing antibody eliminated infection of ECs in the no contact model only. This was consistent with cell-to-cell spread of EHV-1 infection from leucocytes to ECs, demonstrating the importance of this mode of infection in the presence of antibody, and the utility of this model for study of cellular interactions in EHV-1 infection of ECs.  相似文献   
947.
Large scale surveillance of FMD non-structural protein (NSP) antibody in pigs was conducted to monitor for FMD virus circulation in Taiwan using Ceditest and UBI NSP ELISA kits after recurrence of FMD in 2009. A total of 53,759 serum samples were collected from pigs in the auction markets in 2009. There were 43 farms with positive FMD NSP reactors to both NSP ELISA tests in the nationwide surveillance. After tracing back, clinical examination and the NSP ELISA testing using both Ceditest and UBI on 14 follow-up serum samples from all the herds with confirmed NSP reactors in 2009, there were 4 farms classified as positive on follow-up testing criteria. In this surveillance, we have demonstrated that the NSP ELISA tests of outbreak farms followed by clinical and serological investigation could be used to detect FMD circulation in the pig population in Taiwan even while the national compulsory vaccination program is ongoing.  相似文献   
948.
The morphology of the tongue of the adult barking deer, Muntiacus muntjak, was examined by light and scanning electron microscopy. The result showed that the tongue of the barking deer was elongated with a rounded apex. Four types of lingual papillae were observed: filiform, fungiform, vallate and large conical papillae. The filiform papillae represented the most numerous types of lingual papillae. The fungiform papillae were distributed among the filiform papillae on the rostral and the body portions of the tongue. Ten to thirteen vallate papillae were distributed on both sides of the lingual prominence among the large conical papillae. Histologically, both the fungiform and vallate papillae contain taste buds in the epithelial layer. The distribution and types of lingual papillae found in the barking deer are similar to those in the other species that belong to the family Cervidae.  相似文献   
949.
The aim of this study was to evaluate the anticoccidial efficacy of a product containing coumestans from Eclipta alba. Experimental conditions were set up as to reproduce the environment conditions for husbandry adopted in commercial broiler farms. Broilers were raised in broiler chicken shed provided with feeders, drinkers, illumination and temperature control systems and floor covering to afford an adequate nourishing environment. Male Cobb broilers (240) were assigned to four experimental groups being each experimental group set apart in rice straw-covered shed isolated with wire mesh. One-day-old broilers were reared in a coccidian-free environment with ad libitum supply of filtered water and freely available standard feed, from the 1st to the 35th day of life. The T1 group received standard feed (negative control); T2 was treated with standard feed supplemented with 66 ppm of salinomycin (positive control); groups T3 and T4 had standard feed supplemented with the ethyl acetate fraction from methanolic extract of E. alba aerial parts, which contains the coumestans WL and DWL (120 and 180 ppm, respectively). The chicken broilers were individually infected with 2 × 104 oocysts of Eimeria tenella when they were 14 days old and were monitored weekly to evaluate zootechnical parameters such as weight gain and food conversion ratio. Counting of coccidial oocyst in chicken feces was assessed from random samples, from the 21st to 28th days of life, which corresponded to 7-14 days after the infection. Five chickens selected at random from each experimental group were subsequently euthanized at 21, 28 or 35 days of life to determine the lesion score in the cecal region and to excise a cecum portion for histopathological evaluation. The group treated with coumestans from E. alba presented an average weight gain and food conversion ratio higher than the negative control group and similar to the mean value of the positive control group. Coumestan-treated groups showed a significant decrease in the oocyst counting since the 21 th day of life and displayed a reduced number of macroscopic lesions. Histopathological evaluations of cecum fragments showed that both treatments induced the migration of defense cells at the site of infection. A severe destruction of the cecal lining was found in the intestinal tract of broilers fed with a coumestans dose of 180 ppm. Overall, our results validate the use of a phytotherapy containing E. alba coumestans at a dose of 120 ppm as a therapeutic or prophylactic agent against avian coccidiosis.  相似文献   
950.
Accurate radiological interpretation of a navicular bone requires at least a true lateromedial (LM) image, dorsoproximal‐palmarodistal oblique (DPr‐PaDiO) and palmaroproximal‐palmarodistal oblique (PaPr‐PaDIO) images. Additional information is sometimes acquired from a weightbearing dorsopalmar (DPa) image. The LM image is used to assess thickness of the palmar cortex, proximal or distal extension of the palmar cortex, demarcation between the cortex and spongiosa and the presence of periarticular osteophytes. The number, size, shape and position of radiolucent zones along the distal borders of the navicular bone are assessed in a PaPr‐PaDiO image, together with the presence of central or acentric radiolucent osseous cyst‐like lesions in the spongiosa, proximal or distal border entheseophytes, distal or proximal border fragments and a fracture. The PaPr‐PaDiO image is used to identify radiolucent lesions in the palmar cortex and to confirm the thickness of the palmar cortex and the presence of a fracture, and to assess the trabecular architecture of the spongiosa. The presence of a bipartite or tripartite navicular bone is determined from DPr‐PaDiO, PaPr‐PaDiO and DPa images.  相似文献   
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