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61.
We have approached the problem of refrigerated storage of epididymal sperm samples from red deer by comparing three options: storing the genital (testicles within the scrotum), diluting the semen in extender or diluting the semen in extender supplemented with an anti-oxidant. Twenty-nine pairs of testes were collected. Spermatozoa from one of each of the pairs were immediately recovered, and diluted to 400 × 106 sperm/ml in Tris-citrate-fructose with 20% egg yolk. Control group was stored as such, and Anti-oxidant group was supplemented with 0.8 m m vitamin C. The remaining epididymides and the diluted samples were stored at 5°C and spermatozoa were analysed at 0, 24, 96 and 192 h for: motility [computer-assisted semen analysis (CASA)], acrosomal integrity, sperm viability (eosine/nigrosine staining), normal tails and chromatin status [sperm chromatin structure assay (SCSA)]. In general, seminal quality decreased with storage time. Vitamin C supported progressive motility better at 24 h (median 42% vs 23% Control and 15% epididymis), reduced the incidence of tail abnormalities and protected chromatin. Storing the semen in the epididymis slowed down motility loss, but slightly increased the occurrence of tail abnormalities and viability was lower at 192 h. However, regarding chromatin status, sperm stored in the epididymis was protected similarly to those diluted in the medium supplemented with vitamin C. Although the differences between the three groups were small, there were some advantages in supplementing the extender with vitamin C. Besides, refrigerating the epididymis may be a good option when immediate processing is not available.  相似文献   
62.
OBJECTIVE: To assess the efficacy of ivermectin and moxidectin to prevent transmission of Babesia bovis and Babesia bigemina by Boophilus microplus to cattle under conditions of relatively intense experimental challenge. DESIGN: Naive Bos taurus calves were treated with either pour-on or injectable formulations of either ivermectin or moxidectin and then exposed to larvae of B microplus infected with B bovis or larvae or adults of B microplus infected with B bigemina. One calf was used for each combination of haemoparasite, B microplus life stage, drug and application route. PROCEDURE: Groups of calves were treated with the test drugs in either pour-on or injectable formulation and then infested with B microplus larvae infected with B bovis or B bigemina. B bigemina infected adult male ticks grown on an untreated calf were later transferred to a fourth group of animals. Infections were monitored via peripheral blood smears to determine haemoparasite transmission. RESULTS: Cattle treated with either pour-on or injectable formulations of ivermectin and moxidectin became infected with B bovis after infestation with infected larvae. Similarly, larvae infected with B bigemina survived to the nymphal stage to transmit the haemoparasite to animals treated with each drug preparation. Cattle treated with pour-on formulations of ivermectin and moxidectin then infested with adult male ticks infected with B bigemina did not become infected with B bigemina whereas those treated with the injectable formulations of ivermectin and moxidectin did show a parasitaemia. CONCLUSIONS: Injectable or pour-on formulations of ivermectin and moxidectin do not prevent transmission of Babesia to cattle by B microplus. Use of these drugs can therefore not be recommended as a primary means of protecting susceptible cattle from the risk of Babesia infection.  相似文献   
63.
Obesity is a rising problem in cats. It is a risk factor for several diseases and has been linked to impaired immunity. The goal of this study was to determine the effect of body composition and effects of diet on immune function in cats. Twenty-eight short-term obese and 12 lean cats with equal gender distribution were evenly and randomly divided into two groups which were either fed a diet containing saturated (SFA) or long-chain n-3 polyunsaturated fatty acids (3-PUFA) for a period of 6 months prior to testing. Blood was collected by venipuncture from the jugular vein. Blood samples were analyzed in a double blind fashion. A complete blood count was performed and lymphocyte distribution was examined by flow cytometric analysis with specific fluorescein-conjugated subset markers. Immune function was measured as follows: the proliferative activity of different cellular fractions was tested with polyclonal mitogens such as lipopolysaccharide (LPS), phytohaemagglutinin (PHA), phorbol 12-myristate 13-acetate (PMA), Ca ionophore, and concanavalin A. Innate immune functions assessed were phagocytosis and natural killer cell (NK) cytotoxicity. A similar immune innate and adaptive immune response was elicited regardless of diet or body condition. However, there was no correlation between body condition, diet, and any of the quantitative and qualitative functional responses of the immune system. We conclude that short-term obesity and the fatty acid composition of the diet do not alter immune responses in cats.  相似文献   
64.
Seventy‐five female Damascus goats aged between 1.5 and 5.5 years were used to evaluate the effectiveness of the intravaginal sponges and prostaglandin analogue on oestrous synchronization and fecundity; to diagnose pregnancy and to monitor the resumption of the luteal activity. Females were divided randomly, during the breeding season, into three equal groups, S, P and C. Females in group S were fitted with sponges containing 45 mg of flugestone acetate (FGA) for 14 days and injected with pregnant mare serum gonadotrophin (PMSG) at the sponge withdrawal. Females in group P were given two injections of prostaglandin F2α analogue at 11‐day intervals, whereas females in group C (control) received no treatment. The results showed that there was a significant difference (p < 0.001) in oestrous exhibition between females in group S as compared with those in groups P and C, with means being 30 ± 10, 172 ± 115 and 217 ± 75 h for groups S, P and C, respectively. Kidding rates resulting from the first and all matings were 80 and 88, 52 and 88, and 68 and 80% for groups S, P and C, respectively. Fecundity rates were 215, 175 and 180% for groups S, P and C, respectively, with a significant difference (p < 0.05) between the S and both P and C groups. Using an ultrasound pregnancy detector performed on days 57 ± 3 after mating, positive pregnancy diagnosis was 93.3% and 100% for non‐pregnancy. Females in the control group showed functional corpus luteum starting in September. It is concluded that FGA sponges plus PMSG treatment could be successfully used to synchronize oestrus and improve fecundity; whereas prostaglandin treatment was not effective to synchronize oestrus. It is also concluded that pregnancy can be diagnosed accurately and successfully using an ultrasound pregnancy detector. In addition, ovarian activity in the Damascus goat in Syria resumes in September.  相似文献   
65.
Interest in indicus–taurus cattle has been increasing, as these animals are likely to present the best characteristics of Zebu and European bovine breeds. The aim of this study was to compare the embryo production of indicus–taurus donors with high vs low antral follicle counts obtained by ovum pickup/in vitro production (OPU/IVP) and superovulation (SOV)/embryo collection. Braford females at weaning age (3/8 Nelore × 5/8 Hereford, n = 137, 9 ± 1 month old) were subjected to six serial ovarian ultrasonographs and were assigned to two groups according to the number of antral follicles ≥3 mm as follows: G‐High antral follicular count (AFC, n = 20, mean ≥40 follicles) and G‐Low AFC (n = 20, mean ≤10 follicles). When the females (n = 40) reached 24 months of age, they were subjected to both OPU/IVP and SOV/embryo collection. The average number of follicles remained highly stable throughout all of the ultrasound evaluations (range 0.90–0.92). The mean number of COCs recovered (36.90 ± 13.68 vs 5.80 ± 3.40) was higher (p < 0.05) for females with high AFC, resulting in higher (p < 0.05) numbers of total embryos among females with high vs low AFC (6.10 ± 4.51 vs 0.55 ± 0.83). The mean number of embryos per collection was also higher (p < 0.05) for G‐High vs G‐Low (6.95 ± 5.34 vs 1.9 ± 2.13). We conclude that a single ultrasound performed at pre‐pubertal ages to count antral follicles can be used as a predictor of embryo production following IVP and SOV/embryo collection in indicus–taurus females.  相似文献   
66.
67.
A study was carried out to determine the effect of germination and drying temperature on the in vitro protein digestibility and physicochemical properties of dry red bean flours. A 2 x 3 factorial experiment with two treatments (germination and nongermination) and three drying temperatures was used for this purpose. The effect of particle size on water absorption capacity of bean flour was investigated. In addition, the effect of incorporating soybean and cowpea into the red bean flour on functional properties was equally investigated. Results reveal that protein digestibility increased with germination and also with drying temperature. Drying at 60 degrees C produced flours of optimum functional characteristics, although the hydrophilic/lipophilic index was high and the solubility index reduced. Germination and particle size as well as drying temperature all affected the water uptake properties of bean flours. Incorporation of soybean and cowpea flour into germinated bean flour at levels of 10 and 30%, respectively, produced a composite with higher functional properties.  相似文献   
68.
Post-harvest toughening of asparagus spears is associated with a large increase in monomeric and diferulic acids in the cell walls of stem tissues. The purpose of this study has been to investigate the distribution of these phenolic components among cell wall polymers and the role they play in the formation of associated pectic-xylan-phenolic complexes in relation to post-harvest toughening. The phenolic esters are found in all the extractable polysaccharide fractions, particularly the 0.5 M KOH fraction, as well as the insoluble cellulose-rich residue. The storage-related increase occurs in all fractions but is most prominent in the 0.5 M KOH-soluble components. Degradation of 0.5 M KOH subfractions with pure polysaccharide degrading enzymes has confirmed the occurrence of pectic-xylan-phenolic complexes in which ferulic acid and its dehydrodimers are attached to the xylan component but not to the pectic component. Studies on cell separation show that the maturation- and storage-related increase in thermal stability of cell adhesion (and therefore texture) is probably due to an increase in phenolic cross linking of xylans mainly in the parenchyma tissues. This overcomes the thermal lability of the pectic polysaccharides that are responsible for cell adhesion in immature tissues. The storage-induced appearance of some of the diferulic acid moieties in a number of wall polymer fractions supports the hypothesis that the storage affect is a wound-induced response rather than a continuation of maturation-related activity.  相似文献   
69.
Ferulic acid (FA) cross-links have been implicated in the thermal stability of texture in Chinese water chestnut (CWC) tissues. The aim of the current study has been to investigate this concept further. CWC tissue strips were measured for their mechanical properties before and after extraction in increasing strengths of alkali. The mechanical properties were related to the associated mode of fracture (cell separation or breakage) at the fracture surfaces and the phenolic composition of the cell walls. CWC tissue softened after prolonged extraction in cold alkali due to an increase in the ease of cell separation. Analysis of wall-bound phenolics demonstrated that most FA moieties, including five of the six dehydrodimers, were released before tissue strength was reduced. Loss of strength was, however, coincident with the loss of 8,8'-diferulic acid, aryltetralin (AT) form. It has been suggested that this dehydrodimer may be particularly concentrated at the edge of the cell faces. These results provide further evidence for the involvement of this dehydrodimer in conferring thermal stability of cell-cell adhesion and hence texture in CWC. However, they do not exclude the other diferulates from involvement in cell adhesion.  相似文献   
70.
The effects of tolazoline (4.0 mg/kg iv) antagonism of detomidine (0.02 mg/kg iv) were evaluated in isoflurane-anaesthetised, ventilated ponies. Each of 6 ponies received both tolazoline and saline treatment during separate anaesthetic episodes only (no surgery was performed). Detomidine administration produced an increase in blood pressure, decrease in heart rate and decrease in PaO2 Tolazoline treatment transiently increased heart rate while blood pressure returned to baseline after both treatments. Arterial oxygenation decreased further after tolazoline treatment while oxgenation recovered towards baseline with saline treatment. No other cardiopulmonary effects were detected. Recovery from anaesthesia tended to be more rapid when detomidine was antagonized. The potential benefit of antagonizing detomidine-induced bradycardia with tolazoline, during isoflurane anaesthesia should be weighed against the potential to produce a decrease in arterial oxygenation. The mechanism for this effect is not clear.  相似文献   
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