Short communication: Detection of antibiotic resistance,mecA, and virulence genes in coagulase-negative Staphylococcus spp. from buffalo milk and the milking environment

The aim of this study was to determinate whether coagulase-negative staphylococci (CNS) from buffalo milk or the milking environment possess virulence factors that are associated with intramammary infections or antimicrobial resistance. Milk samples (n = 320) from 80 lactating buffalo were evaluated for clinical and subclinical mastitis by physical examination, the strip cup test, California Mastitis Test (CMT), and somatic cell count (SCC) over a 4-mo period. In addition, swabs were obtained from the hands of consenting milkers (16), liners (64), and from the mouths (15) and nostrils (15) of buffalo calves. No clinical cases of mastitis were observed; however, CMT together with SCC results indicated that 8 animals had subclinical mastitis. Eighty-four CNS isolates were identified by MALDI-TOF MS and cydB real-time PCR (qPCR) and then evaluated by qPCR for presence of the eta, etb, sea, sec, cna, seb, sei, seq, sem, seg, see, and tst toxin genes, adhesion- and biofilm-associated genes (eno, ebps, fib, fnbA, coa), and the methicillin resistance gene (mecA). Resistance to antibiotics commonly used for mastitis treatment in Brazil was determined using the Kirby-Bauer test. Two strains were positive for the see and eta toxin genes; and mecA (1), eno (27), ebps (10), fnbA (10), and coa (5) genes were also detected. A notable number of isolates were resistant to erythromycin (30), penicillin (26), and cotrimoxazole (18); importantly, 10 vancomycin-resistant isolates were also detected. A smaller number of isolates were resistant to rifampicin (8), oxacillin (7), clindamycin (5), cefepime (4), tetracycline (3), ciprofloxacin (2), and chloramphenicol (1), and none were resistant to gentamicin or ciprofloxacin. Isolates with resistance to 2 (13 isolates), 3 (3), 4 (3), 5 (1), and 6 (1) antibiotics were detected. Taken together, our findings suggest that CNS isolates may not be a significant cause of clinical or even subclinical mastitis in buffaloes, but they may be a reservoir of virulence and antibiotic resistance genes.     

Factors affecting variations in the detailed fatty acid profile of Mediterranean buffalo milk determined by 2-dimensional gas chromatography

Buffalo milk is the world's second most widely produced milk, and increasing attention is being paid to its composition, particularly the fatty acid profile. The objectives of the present study were (1) to characterize the fatty acid composition of Mediterranean buffalo milk, and (2) to investigate potential sources of variation in the buffalo milk fatty acid profile. We determined the profile of 69 fatty acid traits in 272 individual samples of Mediterranean buffalo milk using gas chromatography. In total, 51 individual fatty acids were identified: 24 saturated fatty acids, 13 monounsaturated fatty acids, and 14 polyunsaturated fatty acids. The major individual fatty acids in buffalo milk were in the order 16:0, 18:1 cis-9, 14:0, and 18:0. Saturated fatty acids were the predominant fraction in buffalo milk fat (70.49%); monounsaturated and polyunsaturated fatty acids were at 25.95 and 3.54%, respectively. Adopting a classification based on carbon-chain length, we found that medium-chain fatty acids (11–16 carbons) represented the greater part (53.7%) of the fatty acid fraction of buffalo milk, whereas long-chain fatty acids (17–24 carbons) and short-chain fatty acids (4–10 carbons) accounted for 32.73 and 9.72%, respectively. The n-3 and n-6 fatty acids were 0.46 and 1.77%, respectively. The main conjugated linoleic acid, rumenic acid, represented 0.45% of total milk fatty acids. Herd/test date and stage of lactation were confirmed as important sources of variation in the fatty acid profile of buffalo milk. The percentages of short-chain and medium-chain fatty acids in buffalo milk increased in early lactation (+0.6 and +3.5%, respectively), whereas long-chain fatty acids decreased (?4.2%). The only exception to this pattern was butyric acid, which linearly decreased from the beginning of lactation, confirmation that its synthesis is independent of malonyl-CoA. These results seem to suggest that in early lactation the mobilization of energy reserves may have less influence on the fatty acid profile of buffalo milk than that of cow milk, probably due to a shorter and less severe period of negative energy balance. Parity affected the profiles of a few traits and had the most significant effects on branched-chain fatty acids. This work provided a detailed overview of the fatty acid profile in buffalo milk including also those fatty acids present in small concentrations, which may have beneficial effects for human health. Our results contributed also to increase the knowledge about the effects of some of the major factors affecting buffalo production traits and fatty acid concentrations in milk, and consequently its technological and nutritional properties.     

水牛初乳粉减轻糖尿病大鼠氧化应激的作用

目的：观察水牛初乳粉对Ⅰ型糖尿病大鼠血清抗氧化水平及脏器指数的影响。方法：采用腹腔注射65mg/kg bw链脲佐菌素诱导建立糖尿病大鼠模型,大鼠随机分为正常组、糖尿病模型组、药物组和水牛初乳组,正常组和糖尿病模型组灌胃灭菌水,药物组和水牛初乳组分别灌胃盐酸二甲双胍和水牛初乳粉溶液,定期检测血糖,第31 天采血,用比浊法检测血清抗氧化指标,并称取各脏器质量,计算脏器指数。结果：水牛初乳能够降低糖尿病初期大鼠的血糖(P ＜ 0.01 和P ＜ 0.05),显著提高大鼠血清SOD 活力(P ＜ 0.01),显著降低血清NO 含量(P ＜ 0.05),使胰脏和肺脏指数显著减小(P ＜ 0.01 和P ＜ 0.05)。结论：水牛初乳粉能够控制Ⅰ型糖尿病初期大鼠的血糖值,增强机体的抗氧化能力,减轻氧化应激程度,并保护胰腺和肺脏。     

Effect of Yeast Culture Supplement on Ruminal Microbial Populations and Metabolism in Buffalo Calves Fed a High Roughage Diet

The effect of Saccharomyces cerevisiae yeast culture (YC, Yea-Sacc 1026) as a supplement to the high-roughage diet of buffalo calves on the rumen microbial populations, fermentation pattern and in sacco dry matter disappearance of dietary constituents was examined. A control group was fed a diet consisting of, on a dry matter basis, 2·12 kg bajra (Pennisetum typhoides) hay and 0·45 kg groundnut cake per day per calf, while the treatment group had the same diet plus 5 g YC. After feeding for 6 weeks, inclusion of YC was stopped and both groups were given the control diet for 2 weeks. At week 4 the pH in the rumen fluid (RF) was significantly higher (P<0·05) up to 6 h post-feeding in the treatment group compared with the control group. The concentrations of total, total viable and cellulolytic bacteria were increased by 41·0 (P<0·05), 33·5 and 57·4% (P<0·01), respectively, with YC supplement. The concentration of total volatile fatty acids (P<0·05), particularly at 4 h post-feeding (P<0·01) and acetate (P<0·01) and acetate to propionate ratio (P<0·05) were higher in the treatment compared with the control group. On YC supplementation, the concentration of NH₃-N was decreased (P<0·05) while that of TCA-precipitable protein in RF was marginally but non-significantly increased. Withdrawal of YC from the diet reversed these effects and the rumen variables returned to values close to control levels after 2 weeks. The in sacco dry matter disappearance of dietary components was higher in the treatment compared with the control group, particularly during the first 24 h of incubation. © 1997 SCI.     

提高水牛奶稳定性的研究

本文研究了乳化剂、胶体及盐对水牛奶油脂析出率、离心沉淀率和粘度的影响,结果表明,单甘酯和蔗糖酯用量比为4:1且总量为1.5 ‰,羧甲基纤维素钠添加量为0.2 ‰,柠檬酸钠添加量为0.2 ‰时,水牛奶的油脂析出率、离心沉淀率明显降低,粘度提高,产品风味浓郁、口感饱满.     

利用水牛乳资源优势,开发南方特色乳制品

介绍了我国奶水牛产业的发展状况，水牛乳的理化、加工特性，水牛乳的加工状况，干酪在我国的发展状况，分析了我国南方发展水牛乳干酪的条件、优势和前景，提出了南方发展水牛乳干酪的设想。     

Electrophysiologically and Behaviorally Active Volatiles of Buffalo Gourd Root Powder for Corn Rootworm Beetles

The dried, powdered roots of buffalo gourd, Cucurbita foetidissima, were tested in a cornfield and shown to attract adult northern and southern corn rootworm beetles. Coupled gas chromatography–electroantennography (GC-EAG) analyses of headspace samples of the root powder showed several GC-EAG-active compounds on the antennae of female northern, southern, and western corn rootworms. Among other techniques, solid-phase microextraction and GC-mass spectrometry identified the following GC-EAG-active compounds: hexanol, nonanal, 1-octen-3-ol, benzaldehyde, benzyl alcohol, (E)-3-octen-2-one, (E,E)-3,5-octadien-2-one, and (E,Z)-3,5-octadien-2-one. EAG dose–response studies of several of the identified root powder volatiles also were performed and compared with results from known attractants. Field tests of synthetic root powder volatiles in commercial cornfields showed that northern corn rootworm adults were attracted to (E,E)-3,5-octadien-2-one. The antennae of the Diabrotica species and the field tests showed specificity for different geometrical isomers of 3,5-octadien-2-one, with a behavioral preference for (E,E)-3,5-octadien-2-one. In addition, we have shown that the efficacy of buffalo gourd root powder as a feeding stimulant and arrestant can be enhanced for northern and western corn rootworm adults by augmenting buffalo gourd root powder with additional (E,E)-3,5-octadien-2-one.     

水牛奶奶油冰淇淋的研制

以水牛奶奶油为主要基料,加入奶粉、白砂糖、复配增稠剂等,以感官评分为参考,研究开发一款特色水牛奶冰淇淋.通过单因素试验研究奶粉、水牛奶奶油、蛋黄粉、白砂糖、复配增稠剂、浓缩蛋白粉添加量对产品感官质量的影响,在单因素的基础上,结合二次通用旋转组合设计优化确定水牛奶冰淇淋的最佳配方,并研究其产品质量.结果表明,水牛奶冰淇淋...     

Genome-wide analysis of runs of homozygosity in Italian Mediterranean buffalo

Runs of homozygosity (ROH) are a powerful tool to explore patterns of genomic inbreeding in animal populations and detect signatures of selection. The present study used ROH analysis to evaluate the genome-wide patterns of homozygosity, inbreeding levels, and distribution of ROH islands using the SNP data sets from 899 Mediterranean buffaloes. A total of 42,433 ROH segments were identified, with an average of 47.20 segments per individual. The ROH comprising mostly shorter segments (1–4 Mb) accounted for approximately 72.29% of all ROH. In contrast, the larger ROH (>8 Mb) class accounted for only 7.97% of all ROH segments. Estimated inbreeding coefficients from ROH (F_ROH) ranged from 0.0201 to 0.0371. Pearson correlations between F_ROH and genomic relationship matrix increased with the increase of ROH length. We identified ROH hotspots in 12 genomic regions, located on chromosomes 1, 2, 3, 5, 17, and 19, harboring a total of 122 genes. Protein-protein interaction (PPI) analysis revealed the clustering of these genes into 7 PPI networks. Many genes located in these regions were associated with different production traits. In addition, 5 ROH islands overlapped with cattle quantitative trait loci that were mainly associated with milk traits. These findings revealed the genome-wide autozygosity patterns and inbreeding levels in Mediterranean buffalo. Our study identified many candidate genes related to production traits that could be used to assist in selective breeding for genetic improvement of buffalo.