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BLAD is an autosomal recessive genetic disease that affects Holstein-Friesian (HF) cattle worldwide. It is a disease characterized by a reduced expression of the adhesion molecules on neutrophils. The disease is caused by a mutation that replaces adenine at 383 with guanine, which causes an amino acid change from aspartic acid to glycine. Blood samples and a few semen samples were collected from 1250 phenotypically normal individuals, including HF (N = 377), HF crossbred (N = 334), Jersey (105), other breeds of cattle (N = 160) and water buffalo Bubalus bubalis (N=274) belonging to various artificial insemination stations, bull mother farms (BMFs) and embryo transfer (ET) centres across the country. PCR-RFLP was performed to detect a point mutation in CD18, surface molecules of neutrophils. The results indicate that out of 1250 cattle and buffaloes tested for BLAD, 13 HF purebreds out of 377 and 10 HF crossbreds out of 334 appear to be BLAD carriers. In the HF and HF crossbred population, the percentage of BLAD carriers was estimated as 3.23%. The condition is alarming as the mutant gene has already entered the HF crossbred cattle population and therefore, the population of HF and its crossbreds needs regular screening to avoid the risk of spreading BLAD in the breeding cattle population of India.
The present study investigated the occurrence of 2 autosomal recessive genetic diseases, bovine citrullinaemia and deficiency of uridine monophosphate synthase (DUMPS), in Indian Holstein cattle. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was performed on a group of 642 animals, mainly HF and HF crossbred cattle, to identify carriers of these diseases. None of the animals were carriers of citrullinaemia or DUMPS. It is possible that with the mounting selection pressure, the international gene pool may diminish, and consequently the risk of dissemination of inherited defects will increase. It is therefore recommended to screen breeding bulls for their breed-specific genetic diseases before they are inducted in artificial insemination programmes, to minimize the risk.
In the milk industry in India, buffalo breeds are most commonly used for milk production. Efficiency of fiber digestion in ruminants is critical for animal productivity. Bacteria play an important role in fiber digestion and utilization. Absolute quantification real-time PCR was used to quantify ten bacterial species in rumen fluid of Surti buffalo fed green fodder, dry roughage and compound concentrate mixture. Abundance of each target taxon was calculated as a fraction of the total 16S rRNA gene copies in the samples, using taxon-specific primers. Bacterial populations showed a clear predominance of Ruminococcus albus, which comprised 5.66% of the bacterial rRNA gene copies in the samples. However, only 0.9% to 4.24% of the bacterial rRNA gene copies were represented by the ruminal Fibrobacter succinogenes, Ruminococcus flavefaciens and Prevotella species. The proportion of rRNA gene copies attributable to Selenomonas ruminantium, Streptococcus bovis, Ruminobacter amylophilus, Treponema bryantii and Anaerovibrio lipolytica was even less abundant, each comprising <0.11% of the bacterial rRNA gene copies. The data suggest that the aggregate abundance of the most intensively studied ruminal bacterial species is relatively low and that a large fraction of the uncultured population represents a single bacterial genus.
Bacterial communities in buffalo rumen were characterized using a culture-independent approach for a pooled sample of rumen fluid from 3 adult Surti buffaloes. Buffalo rumen is likely to include species of various bacterial phyla, so 16S rDNA sequences were amplified and cloned from the sample. A total of 191 clones were sequenced and similarities to known 16S rDNA sequences were examined. About 62.82% sequences (120 clones) had >90% similarity to the 16S rDNA database sequences. Furthermore, about 34.03% of the sequences (65 clones) were 85-89% similar to 16S rDNA database sequences. For the remaining 3.14%, the similarity was lower than 85%. Phylogenetic analyses were also used to infer the makeup of bacterial communities in the rumen of Surti buffalo. As a result, we distinguished 42 operational taxonomie units (OTUs) based on unique 16S r DNA sequences: 19 OTUs affiliated to an unidentified group (45.23% of total OTUs), 11 OTUs of the phylum Firmicutes, also known as the low G+C group (26.19%), 7 OTUs of the Cytophaga-Flexibacter-Bacteroides phylum (16.66%), 4 OTUs of Spirochaetes (9.52%), and 1 OTU of Actmobacteria (2.38%). These include 10 single-clone OTUs, so Good's coverage (94.76%) of 16S rRNA libraries indicated that sequences identified in the libraries represent the majority of bacterial diversity present in rumen.
Methane emissions from ruminant livestock are considered to be one of the more potent forms of greenhouse gases contributing to global warming. Many strategies to reduce emissions are targeting the methanogens that inhabit the rumen, but such an approach can only be successful if it targets all the major groups of ruminant methanogens. Therefore, basic knowledge of the diversity of these microbes in breeds of buffalo is required. Therefore, the methanogenic community in the rumen of Surti buffaloes was analyzed by PCR amplification, cloning, and sequencing of methyl coenzyme M reductase (mcrA) gene. A total of 76 clones were identified, revealing 14 different sequences (phylotypes). All 14 sequences were similar to methanogens belonging to the order Methanobacteriales. Within Methanobacteriales, 12 clones (6 OTUs) were similar to Methanosphaera stadtmanae and the remaining 8 phylotypes (64 clones) were similar to unclassified Methanobacteriales. Overall, members of the Methanobacteriales dominated the mcrA clone library in the rumen of Surti buffalo. Further studies and effective strategies can be made to inhibit the growth of Methanobacteriales to reduce methane emission from the rumen which would help in preventing global warming.
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