我国奶水牛业的发展现状及加快发展的建议

我国饲养水牛已有7000多年的历史,主要作役用,水牛在历史上对提高农业生产力水平发挥了极其重要的作用.随着社会的不断进步,以及水牛杂交改良的进展,水牛生产由单一役用向乳、肉、役多用发展.文章主要分析了我国奶水牛业的发展现状、存在问题及发展奶水牛业的重要性和必要性,并提出了加快我国奶水牛业发展的建议.     

中国水牛乳业可持续的发展战略

中国水牛2276.0万头,乳、肉、皮等主要产品产量分别为265.0万t、39.6万t和11.9万t,水牛头数及其主要产品产量居世界前三位,水牛乳主要乳制品也占有一席之地.本地水牛属沼泽型役用水牛,试验证明采用河流型乳用水牛进行杂交改良,杂交二代水牛一个泌乳期泌乳量2000kg以上,可达到河流型乳用水牛的泌乳水平,实现了"耕牛变成奶牛"的目的,以此为基础,中国水牛乳业必然发挥自身的优势而走自己发展的道路.中国水牛乳业发展的重要性、艰巨性和长期性进一步为人们所共识.由于水牛的生物学特性具有适应热带和亚热带气候区域的生存条件,是我国南方诸省开发乳畜特有的潜力和丰富的资源,将对科技进步及人类健康发挥重大的作用.     

水牛产业资源的利用和开发

中国水牛业资源丰富，水牛业生产占有重要的比重。水牛乳、肉是优质乳品和肉品，营养丰富，风味独特，是加工生产具有高档特色的水牛乳、肉制品的主要来源，以满足人们优质、安全、多样食品的需求。随着我国加入WTO和市场经济的发展，中国水牛产业的资源将会进一步挖掘、利用和开发，水牛产业的生命力将会进一步发挥和持续的发展，将对科技进步及人类健康作出新的贡献。     

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。     

我国乳肉兼用型水牛繁育成功

据《中国食品报》报道:我国乳肉兼用型水牛的繁育技术,最近在广西壮族自治区南宁市通过鉴定。     

水牛乳肉生产及其展望

一、水牛头数及乳肉生产 (一)水牛头数 据联合国粮农组织(FAO)(《生产年鉴》(2000)资料统计(见表1):全世界有水牛16506.2万头,占世界养牛总数的12.22%,分布于5大洲50多个国家,年均增长率0.98％。水牛主要饲养于亚洲发展中国家,特别是在印度、巴基斯坦和中国等3个国家,水牛饲养量13905.9万     

酒精阳性水牛乳乳成分及理化性质的研究

本研究连续一年观测了摩拉水牛、尼里-拉菲水牛、一代杂水牛和三品杂水牛4个种水牛乳64%的不同季节的酒精阳性发生率、乳成分、理化性质,并比较了酒精阳性乳、阴性乳与乳样总体的差异。结果表明,纯种河流型水牛(摩拉水牛、尼里-拉菲水牛)乳酒精阳性率低于两个杂交水牛(三品杂水牛、一代杂水牛),各品种水牛乳均以2~4月和8~10月的阳性率为最高。低酸度酒精阳性乳(12~18oT)占据了酒精阳性乳的52.9%~64.1%。酒精阳性乳的乳蛋白、乳固体、非脂乳固体、酸度均显著高于阴性乳和乳样总体平均值,但冰点低于乳样总体平均值。可见不同品种水牛乳不能用同一酒精浓度进行检验;酒精阳性率可反映水牛应激或营养状况;较高的乳蛋白、非脂乳固体、总乳固体、酸度以及较低的冰点是酒精阳性水牛乳的特征;酸度和冰点是品种间酒精阳性率差异的主要因素。     

不同品种水牛乳中矿物元素的测定与分析

为阐明不同奶水牛品种的水牛乳在不同泌乳期的微量元素变化,采集了我国摩拉水牛、尼里-拉菲水牛、以及上述两种水牛加本地水牛(即三品种杂交水牛,以下简称"三杂水牛")在泌乳第15,45,150和200 d的乳样,同时采集了荷斯坦奶牛和娟姗牛的乳样,用ICP-AES法分析乳中几种常量和微量元素的质量浓度。结果表明,水牛乳中矿物元素除钾和钠外,各种矿物元素质量浓度均高于荷斯坦和娟姗牛。以平均值计,水牛乳钙、铁、锌的质量浓度分别是荷斯坦牛乳的1.7,13.0和1.7倍。泌乳期是影响水牛乳矿物元素质量浓度的主要因素,其中以早期和末期质量浓度较高。各品种水牛乳间矿物元素质量浓度无显著差异,但尼里-拉菲水牛乳总体偏低。     

不同品代水牛奶理化性质的研究

研究了摩拉水牛、尼里-拉菲水牛、一代杂交水牛、二代杂交水牛、高代杂交水牛等5个品代水牛奶的理化性质。结果表明,杂交水牛奶的全乳固体、乳脂肪、蛋白质、乳糖的平均值均高于纯种摩拉水牛和尼里-拉菲水牛,杂交水牛奶的灰分总体高于纯种河流型水牛,在杂交水牛中,由高到低的顺序为:一代杂、二代杂、高代杂。纯种摩拉水牛和尼里-拉菲水牛之间的全乳固体、乳脂肪、蛋白质和乳糖差异不显著(P>0.5),而杂交水牛的全乳固体、乳脂肪、蛋白质和乳糖与纯种河流型水牛相比,差异显著(P<0.05)。各品代水牛之间钙、磷含量的差异不显著(P>0.5),但从总体上看,杂交水牛的含量要高于纯种河流型水牛,杂交水牛中又以杂交一代水牛为最高。各品代水牛奶的各种氨基酸含量随蛋白质总量的变化而变化,除杂交水牛之外,各品代水牛之间的各种氨基酸比例比较接近。各品代水牛奶的密度平均值变化范围为1.028～1.032;酸度平均值变化范围是15.36～19.82°T;pH值的平均值变化范围从6.46～6.88;黏度平均值的变化范围由2.44～3.11 Pa.s。     

水牛乳过氧化物酶特性的研究

以第三代摩拉×本地奶水牛的新鲜乳为原料,对乳中过氧化物酶的最适温度、热稳定性、最适pH值、pH值稳定性以及光稳定性用ABTS进行测定。结果表明,乳中过氧化酶最适合温度在55℃附近,且在40℃以下稳定性较好;最适pH值在5.5附近,pH值为3.0～8.0都很稳定;日光灯照射条件下,酶的稳定性较差而避光条件下相对较好。这些研究将为南方以及广西地区水牛乳的保鲜提供了部分依据。     

Genome-wide association studies to identify quantitative trait loci affecting milk production traits in water buffalo

Water buffalo is the second largest resource of milk supply around the world, and it is well known for its distinctive milk quality in terms of fat, protein, lactose, vitamin, and mineral contents. Understanding the genetic architecture of milk production traits is important for future improvement by the buffalo breeding industry. The advance of genome-wide association studies (GWAS) provides an opportunity to identify potential genetic variants affecting important economical traits. In the present study, GWAS was performed for 489 buffaloes with 1,424 lactation records using the 90K Affymetrix Buffalo SNP Array (Affymetrix/Thermo Fisher Scientific, Santa Clara, CA). Collectively, 4 candidate single nucleotide polymorphisms (SNP) in 2 genomic regions were found to associate with buffalo milk production traits. One region affecting milk fat and protein percentage was located on the equivalent of Bos taurus autosome (BTA)3, spanning 43.3 to 43.8 Mb, which harbored the most likely candidate genes MFSD14A, SLC35A3, and PALMD. The other region on the equivalent of BTA14 at 66.5 to 67.0 Mb contained candidate genes RGS22 and VPS13B and influenced buffalo total milk yield, fat yield, and protein yield. Interestingly, both of the regions were reported to have quantitative trait loci affecting milk performance in dairy cattle. Furthermore, we suggest that buffaloes with the C allele at AX-85148558 and AX-85073877 loci and the G allele at AX-85106096 locus can be selected to improve milk fat yield in this buffalo-breeding program. Meanwhile, the G allele at AX-85063131 locus can be used as the favorable allele for improving milk protein percentage. Genomic prediction showed that the reliability of genomic estimated breeding values (GEBV) of 6 milk production traits ranged from 0.06 to 0.22, and the correlation between estimated breeding values and GEBV ranged from 0.23 to 0.35. These findings provide useful information to understand the genetic basis of buffalo milk properties and may play a role in accelerating buffalo breeding programs using genomic approaches.     

Evaluation of the performance of the first automatic milking system for buffaloes

The objective of this study was to evaluate the response of buffaloes to automatic milking, examining the relationships between milking interval, milk production, and milking time for this species. A total of 7,550 milking records from an average of 40 buffaloes milked by an automatic milking system (AMS) were analyzed during a 3-mo experimental period at a commercial farm with Italian Mediterranean buffaloes in southern Italy. Date and time of animal identification, milk yield, milking duration, milking interval, and average milk flow rate were determined for each milking. The results were also used to predict the maximum number of milkings per day and the optimal number of buffaloes per AMS for different levels of milk production. The average interval period between 2 consecutive milkings was 10.3 h [standard deviation (SD) 3.3]. Overall, 3.4 and 25.7% of the milkings had an interval of ≤6 h or >12 h, respectively. Milking duration averaged 8.3 min per buffalo per milking (SD 2.7). The average milk flow rate was 1.3 kg/min (SD 0.5) at a milk yield of 2.8 kg per milking (SD 1.4). Assuming that the milking station is occupied 80% of the time, the number of milkings ranged from 136 to 152 per day and the optimal number of buffaloes per AMS ranged from 59 to 66 when the production level increased from 2 to 5 kg of milk per milking. Automatic milking systems are suitable for buffalo, opening new options for the management of dairy buffalo farms.     

Effect of age and gender on the processing characteristics of buffalo meat

Comparison of processing characteristics of meat from young male, spent male and spent female buffaloes was made to find the suitability of the meat for developing ready to eat meat products. Intensively reared young male buffalo meat showed higher moisture, collagen solubility, sarcomere length, myofibrillar fragmentation index and water holding capacity than meat from the other animals. A higher pH, total meat pigments, salt soluble protein, emulsifying capacity and lower collagen solubility were observed in spent male buffalo meat. Spent female buffalo meat had higher fat, total collagen, muscle fibre diameter and shear force value. Sensory evaluation of pressure cooked meat chunks indicated a marked toughness in spent male and female buffalo meat samples. These results suggest that young male buffalo meat is more suitable for processing in chunks and spent male and female buffalo meat is more suitable for processing in smaller particles.     

Comparison of carcase yield, carcase composition and quality characteristics of buffalo meat and beef

The yield of carcase and by-products was found to be only slightly different between buffaloes and non-improved (Busha) cattle of comparable age, feeding treatment and sex. The percentage of separable fat was slightly higher, and that of bone slightly lower, in the buffaloes. In comparing the meat from buffalo and Simmental cattle of the same age and finish, a rather higher protein content was found in the former, but this reflected a somewhat higher concentration of connective tissue in the buffalo meat. The diameter of muscle fibres in buffalo tended to be less than that of corresponding muscle in Simmental cattle (except in M. Supraspinatus of cows). These findings suggest that buffalo meat is no coarser than beef when valid comparisons are made.     

Relationships between somatic cell count and intramammary infection in buffaloes

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.     

Signatures of selection reveal candidate genes involved in production traits in Chinese crossbred buffaloes

Identification of selection signature is important for a better understanding of genetic mechanisms that affect phenotypic differentiation in livestock. However, the genome-wide selection responses have not been investigated for the production traits of Chinese crossbred buffaloes. In this study, an SNP data set of 133 buffaloes (Chinese crossbred buffalo, n = 45; Chinese local swamp buffalo, n = 88) was collected from the Dryad Digital Repository database (https://datadryad.org/stash/). Population genetics analysis showed that these buffaloes were divided into the following 2 groups: crossbred buffalo and swamp buffalo. The crossbred group had higher genetic diversity than the swamp group. Using 3 complementary statistical methods (integrated haplotype score, cross population extended haplotype homozygosity, and composite likelihood ratio), a total of 31 candidate selection regions were identified in the Chinese crossbred population. Here, within these candidate regions, 25 genes were under the putative selection. Among them, several candidate genes were reported to be associated with production traits. In addition, we identified 13 selection regions that overlapped with bovine QTLs that were mainly involved in milk production and composition traits. These results can provide useful insights regarding the selection response for production traits of Chinese crossbred buffalo, as identified candidate genes influence production performance.     

广西本地水牛与黄牛肉品质的比较

为挖掘水牛作为肉用开发潜力,选取广西本地沼泽型杂交水牛与黄牛各6头进行了肉品质的比较分析。结果表明,水牛与黄牛里脊肉和背最长肌肉的大理石花纹等级、L*、a*、b*值均无显著差异(p>0.05),但水牛里脊肉和背最长肌肉的肌肉颜色等级评分均显著高于黄牛肉(p<0.05)。水牛背最长肌肉中的干物质、蛋白质及钙含量显著低于黄牛(p<0.05)。水牛里脊肉的p H显著低于黄牛(p<0.05),但是在背长肌中却未见显著差异(p>0.05)。水牛肉与黄牛肉的熟肉率均在63%以上,但两者差异不显著(p>0.05)。水牛里脊肉中除豆蔻酸低于黄牛(p<0.05)外,其他脂肪酸均无显著差异;水牛背最长肌的豆蔻酸、棕榈酸、亚油酸显著低于黄牛(p<0.05),但其硬脂酸、油酸和亚麻酸要显著高于黄牛(p<0.05)。两者不同部位肌肉中的脂肪酸含量均以油酸含量为最高。水牛里脊肉和背最长肌肉外观颜色比黄牛肉更为暗红;水牛除背最长肌肉干物质、蛋白质、钙、豆蔻酸、棕榈酸及亚油酸含量显著低于黄牛肉,而硬脂酸、油酸和亚麻酸显著高于黄牛外,两者在其他营养指标方面没有显著差异,所测脂肪酸类别中均以油酸含量为最高。以上结果表明,长期作为役用的水牛具有与黄牛类似的肉用潜力。      

Fiber types in the longissimus muscle from water buffalo and selected domestic beef breeds

The distribution and area of longissimus muscle fiber types from two intact male water buffaloes, one Angus bull and one Charolais bull were evaluated. Only fibers of aerobic-oxidative capacity were present in the muscles of the water buffalo examined. The absence of αW fibers may imply some significant and distinct differences in muscle metabolic and functional characteristics. All three fibers types were present in the muscles from the Angus and Charolais bulls. These findings may implicate distinct and unique differences in meat characteristics from water buffalo, such as in organoleptic and/or processing traits.     

Comparative study of buffalo meat and beef

The aim of the experiment described in this paper was to compare buffalo and cattle breeds for meat production. Bulls and steers of both species were compared. Buffaloes and cattle were of comparable conformation on a weight to length ratio basis when slaughtered at the same liveweight. Apart from sex and weight effects, species did affect the conformation and growth of live animals, the largest differences between species being evident in the younger animals. As regards slaughter characteristics, although differences in carcass yield were slight between species, systematic differences appeared, with a higher head and skin weight for buffaloes. A higher proportion of fat was noted in the 11th rib joint of buffaloes than of cattle at the lighter weights but the difference between species lessened with slaughter weight. As far as meat quality is concerned, two major effects of species on muscle pH (24 h post slaughter) and the shear strength of raw muscle were noted. Buffaloes, which had a lower muscle pH than cattle, displayed a significantly smaller amount of collagen in the muscles studied, but the species did not differ significantly in the degree of intramuscular collagen crosslinking.     

Hormone variations in serum and milk of buffaloes (Bubalus bubalis) as potential indicators of treatment with recombinant bovine somatotropin

Recombinant bovine somatotropin (rbST) is used to increase milk yield in cows, but it has been forbidden in some countries and in the EU. However, rbST misuse represents a concern in both bovine and buffalo dairy production. A number of studies on rbST treatment have been performed on bovines, but there are few data on buffaloes. In this study, we treated eight lactating buffaloes with biweekly injections of a slow-release formulation of rbST, for five cycles of administration, and analysed total ST and insulin-like growth factor 1 (IGF-1) variations in serum and IGF-1 in milk. The aim was to assess their power as potential indicators of rbST-treatment. Blood was collected on days 2, 5, 9 and 14 of each cycle, and milk on days 2, 9 and 14 of cycles 2 and 5. Results showed an extraordinary increase in ST levels on day 2 in treated animals, followed by a rapid decrease over the following days, while a significant increase in IGF-1 was observed both in serum and in milk throughout most of each cycle. These results suggest that serum ST levels are a good indicator of treatment. However, the rapid decrease after the peak limits the useful period of sample collection.