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21.
The aim of the present study was to determine if space allocation influenced the concentration of biomolecules in buffalo milk and dairy products. Intensively housed buffaloes (n = 96) were randomly assigned to 2 groups according to days in milk, parity, and milk yield: group S10 had a space allocation of 10 m2 per buffalo and group S15 had a space allocation of 15 m2 per buffalo. Individual milk yield was recorded daily. Twice a month, a bulk milk sample was collected for each group, as well as whey, ricotta, and mozzarella cheese, to assess cheese yield and to conduct HPLC-electrospray ionization-tandem mass spectrometry, milk antioxidant activity, and cell viability analyses. We tested milk extracts from the 2 groups in vitro to evaluate their efficacy in counteracting endothelial oxidative damage induced by high glucose. We evaluated reproductive function in 28 buffaloes from each group using the Ovsynch-timed artificial insemination program. We observed no differences in milk quantity or quality in terms of fat, protein, or lactose, and reproductive function did not differ between the 2 groups. Compared with group S10, group S15 had higher concentrations of carnitine (56.7 ± 1.1 vs. 39.8 ± 0.7 mg/L in milk and 40.9 ± 0.8 vs. 31.7 ± 0.7 mg/L in whey), acetyl-l-carnitine (51.9 ± 0.3 vs. 39.7 ± 0.7 mg/L in milk and 41.1 ± 1.7 vs. 28.7 ± 2.6 mg/L in whey), propionyl-l-carnitine (34.8 ± 1.0 vs. 21.0 ± 0.9 mg/L in milk and 26.9 ± 0.8 vs. 17.6 ± 1.2 mg/L in whey), glycine betaine (23.1 ± 1.9 vs. 13.5 ± 1.6 mg/L in milk and 10.7 ± 0.4 vs. 7.9 ± 0.5 mg/L in whey), and δ-valerobetaine (24.2 ± 0.5 vs. 16.7 ± 0.5 mg/L in milk and 22.0 ± 0.9 vs. 15.5 ± 0.7 mg/L in whey). Group S15 also had higher total antioxidant activity than group S10 (56.7 ± 1.9 vs. 46.4 ± 1.13 mM Trolox equivalents). Co-incubation of high-glucose-treated endothelial cells with milk extracts from group S15 improved cell viability compared with cells treated with high glucose only; it also reduced intracellular lipid peroxidation (144.3 ± 0.4 vs. 177.5 ± 1.9%), reactive oxygen species (141.3 ± 0.9 vs. 189.3 ± 4.7 optical density units), and cytokine release (tumor necrosis factor-α, IL-1β, IL-6). Greater space allocation was associated with higher levels of biomolecules in buffalo milk. This could have been the result of improved welfare in buffaloes that were allocated more space.  相似文献   
22.
以发酵剂的产酸性能、黏度大小、双乙酰含量、pH4.6可溶性氮含量、滋味等五项为评价指标,应用模糊数学综合评价方法评价水牛乳Mozzarella干酪发酵剂中球菌与杆菌比例。结果表明,Lb.与St.以1∶1.2的比率混合时,模糊概率达0.83,菌种的综合品质最好,且与其它比率的菌种在统计学上存在显著差异(p<0.05)。  相似文献   
23.
Yogurt is defined as a coagulated milk product obtained from the fermentation of lactose into lactic acid. Drinking yogurt (laban) was prepared from buffalo milk, cow milk, and a 50:50 blend (cow + buffalo milks) by adding 0.5% carboxymethyl cellulose to each of the 3 milk treatments. Samples were then refrigerated for 7, 14, and 21 d before determination of physical, microbial, and sensory parameters. Yogurt prepared from buffalo milk had higher fat and protein contents, and better taste, aroma, and overall consumer acceptability compared with laban prepared from cow milk or mixed milk. During storage, protein and total solids contents remained unchanged, whereas milk fat, color, appearance, taste, smell, texture, and overall acceptability of laban decreased in the different treatment groups. The acidity of laban increased with storage time. Bacteria, including coliforms, were not found in any treatment group during storage. In conclusion, overall acceptability of laban prepared from buffalo milk was higher than that made from cow milk or mixed milk, but increased storage time reduced the quality of laban prepared from cow, buffalo, or mixed milk.  相似文献   
24.
The longissimus dorsi thoracis (LDT) of 64 water buffalo and 68 Zebu-influenced cattle was used to determine the mineral content variation (mg/100g of fresh tissue) according to species, age (7, 17, 19 and 24 months-of-age, MOA) and gender (steers and bulls). Buffalo LDT had higher concentrations of K, Mn, Fe, Zn and Cu at weaning (P<0.05). Phosphorous content was higher (P<0.05) at post-weaning ages. Mineral profile was affected by age without clear trends; the Na and K contents increased at 24 MOA. The age×species, age×gender and species×gender interactions affected (P<0.05) Fe content that ranged from 1.74 to 2.56mg/100g fresh tissue. Meat from both species contributes with more of 25% of K, P, Fe and Zn of the daily requirement for an adult.  相似文献   
25.
Practical experience has indicated that shooting water buffalo with a captive bolt gun in the front of the head does not always produce an effective stun. Slaughtermen have been claiming that the poll position is more reliable, but under present EU regulations this shooting position is not allowed for domesticated bovines. This study examined the effectiveness of shooting water buffalo with captive bolt guns in the poll region. The depth of concussion was assessed in 30 water buffalo from physical collapse, presence or absence of corneal and palpebral reflexes, normal rhythmic breathing, eyeball rotation, nystagmus and whether the animal was re-shot. All except one animal collapsed immediately. The one animal that failed to collapse was not breathing. The prevalence of a shallow depth of concussion in the poll shot animals was 53%. Two had been shot through the spinal cord, and with the exception of those plus one other in which the bolt did not penetrate the brain, the other animals were considered to be adequately stunned. Post mortem examination of the brain showed that 79% of the under thirty month old animals were shot in the midbrain or brain stem, but these regions had to be avoided in over thirty month old animals because of the risk of damaging the brain stem sample needed for BSE testing. In addition, three water buffalo were shot in the crown position and one in the front of the head. The frontal position was ineffective as the animal did not collapse, and all animals shot in the crown position resumed breathing shortly after shooting, indicating a shallow depth of concussion. It is concluded that poll shooting can be effective in water buffalo, but it produces a shallow depth of concussion compared with frontal shooting in cattle. It requires accurate placement of the gun to ensure that buffalo are not shot through the spinal cord instead of the brain. Vigilance is needed in ensuring that the animals are stuck promptly so that none recover consciousness.  相似文献   
26.
The objectives of this study were to evaluate the presence of intramammary infections (IMI) in dairy buffaloes and to examine the relationships among IMI, somatic cell counts (SCC), and milk production traits. Two farms in northern Italy were visited monthly for a complete milking season. Quarter-based milk samples were collected at each visit from 46 buffaloes. A total of 1,912 samples were assessed in this experiment. Samples were cultured for bacterial presence and were tested for SCC and percentages of milk protein and fat. In addition, daily milk yield was recorded from each buffalo. Prevalence of IMI was large; 63% of quarters were infected. No buffalo remained free from IMI throughout the course of the study. Coagulase-negative staphylococci were the most common pathogen (66% of positive samples). The SCC was distinctly greater in infected quarters; 100% of quarters with SCC >200,000 cell/mL had IMI, whereas 98% of quarters with SCC below this threshold were uninfected. The somatic cell scores (SCS) in these buffaloes were much lower than those commonly observed in dairy cattle. The mean SCS from quarters with IMI was only 2.93. The highest SCS was observed in quarters infected by streptococci. No drastic decrease in milk yield was observed among infected buffaloes relative to healthy contemporaries. The relatively low SCS and lack of a strong effect on milk yield provide evidence to discourage antibiotic treatment of buffaloes for subclinical IMI during lactation.  相似文献   
27.
我国水牛产业现状简析   总被引:3,自引:0,他引:3  
我国水牛多为沼泽型,生长速度较慢,但耐粗饲,疾病少,易饲养,乳、肉生产用潜力较大.现阶段水牛多役用,近些年逐步向乳、肉两用发展.本文分析了我国水牛存栏量、养殖效益、品种及地区分布、屠宰性能等产业概况,并从遗传育种、肉用品质特征两方面介绍我国水牛产业研究现状,结合我国水牛产业存在的问题提出了相应的建议和措施.  相似文献   
28.
The aim of the present study was to assess stall occupancy of Nili Ravi buffaloes when first introduced to freestall housing. Thirty Nili Ravi buffaloes of different parity, weight, and pregnancy status were enrolled from the dairy farm of the University of Veterinary and Animal Sciences, Lahore, Pakistan. All of the enrolled animals had no previous experience with freestalls. The selected buffaloes were introduced to the freestall shed. During an adaptation period of 7 d, all buffaloes had 24 h of free access to lie down in 1 of 3 areas: (1) freestalls, (2) alleys, and (3) an outside open area. After the adaptation period, all buffaloes were housed indoors during nighttime (restricted period) to ensure that only freestalls or alleys were available as lying areas. An observer monitored animals at 0100 h and recorded the number of animals lying in freestalls, in alleys, and in the outside open area. The results indicated that during the adaptation period, herd-level freestall occupancy in buffaloes remained below 10%. During the restricted period, herd-level stall occupancy was 0, 13, 50, and 90% on d 1, 2, 5, and 17, respectively. Buffaloes with parity ≥3 took fewer days (6.6 ± 1.0; mean ± standard error of the mean) to occupy stalls than buffaloes with parity 2, 1, and heifers (13.2 ± 1.5, 16.7 ± 2.1, and 13.5 ± 2.1 d, respectively). Body weight and pregnancy status of buffaloes did not have any effect on stall occupancy. Buffaloes showed adjacent stall occupancy, filling opposite stalls first. The results indicated that older buffaloes occupied freestalls earlier than younger buffaloes. Our findings would help better manage buffaloes in freestall housing.  相似文献   
29.
Forty-four raw milk and 15 serum samples from 44 healthy water buffaloes reared in Caserta, southern Italy, the most important region in Europe for buffalo breeding, were examined to evaluate the presence of Torque teno viruses (TTV) using molecular tools. Furthermore, 8 pooled pasteurized milk samples (from dairy factories having excellent sanitary conditions) and 6 Mozzarella cheese samples were also tested. Four of the cheese samples were commercial Mozzarella cheese; the remaining 2 were prepared with TTV-containing milk. Human TTV were detected and confirmed by sequencing in 7 samples of milk (approximately 16%). No TTV were found in serum, pooled pasteurized milk, or Mozzarella cheese samples. The samples of Mozzarella cheese prepared with TTV-containing milk did not show any presence of TTV, which provides evidence that standard methodological procedures to prepare Mozzarella cheese seem to affect viral structure, making this food fit for human consumption. The 7 TTV species from water buffaloes were identified as genotypes corresponding to the tth31 (3 cases), sle 1981, sle 2031, and NLC030 (2 cases each) human isolates. Although cross-species infection may occur, detection of TTV DNA in milk but not in serum led us to believe that its presence could be due to human contamination rather than a true infection. Finally, the mode of transmission of TTV has not been determined. Contaminated of the food chain with TTV may be a potential risk for human health, representing one of the multiple routes of infection.  相似文献   
30.
The safeguard of river buffalo Mozzarella cheese, a Protected Designation of Origin dairy product, has prompted an analytical study to trace the milk and curd used as raw material in cheesemaking. This is to prevent the illegal use of milk or curd from different geographical areas outside of those indicated in the official production protocol. For this purpose, we studied primary proteolysis occurring in fresh and frozen milk and curd to identify a molecular marker that could indicate the raw material used. Whole casein from frozen river buffalo milk was separated using cation-exchange chromatography and sodium dodecyl sulfate-PAGE, and a protein component with an estimated molecular weight of 15.3 kDa was detected. This protein component was revealed in fresh river buffalo milk as a faint electrophoresis band, which drastically increased in intensity in refrigerated and frozen milk as well as in curd and was found to be associated with β-CN through hydrophobic interaction. By using matrix-assisted laser desorption/ionization-time of flight peptide mass mapping, this component was identified as the C-terminal fragment f(69-209) of β-CN (expected molecular weight of 15,748.8 Da). β-Casein f(69-209), originating from the early hydrolysis of Lys68-Ser69 by plasmin, has no counterpart in bovine milk. The increased rate of hydrolysis by plasmin toward the cleavage site Lys68-Ser69 has to be ascribed to the elevated proline content of the peptide 61-73. The favored production of β-CN f(69-209) has also drawn attention to the complementary proteose peptone β-CN f(1-68) that is presumed to play a physiological role in inducing milk secretion similar to that of β-CN f(1-29). The higher in vivo and in vitro production rate, compared with γ1-CN formation, indicates that β-CN f(69-209) and its complementary fragment are candidate molecular markers to evaluate milk and curd freshness. We used indirect ELISA analysis based on the determination of remaining nonhydrolyzed β-CN to perform a quantitative evaluation of proteolysis.  相似文献   
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