Bovine leukocyte adhesion deficiency in Danish Holstein-Friesian cattle. I. PCR screening and allele frequency estimation

Unveiling genetic variants: Tetra-primer ARMS-PCR diagnosis and structural insights into BLAD, BC, and DUMPS in Pakistani cattle herds

BACKGROUND

Bovine leukocyte adhesion deficiency (BLAD), bovine citrullinemia (BC), and deficiency of Uridine monophosphate synthetase (DUMPS) are the common autosomal recessive disorders affecting the global dairy industry. BLAD leads to poor wound healing and recurrent infections. In BC, ammonia builds up leading to neurological disorders and death. DUMPS results in developmental abnormalities.

METHODOLOGY

In this study, tetra-primer amplification refractory mutation system polymerase chain reaction (ARMS PCR) based diagnostic tests were optimized for BLAD, BC, and DUMPS. A total of 250 animals (58 indigenous and 192 Holstein Friesian (HF)) were screened from all across Pakistan. In addition to validation of ARMS-PCR results through Sanger sequencing, the protein modeling provided structural insights of the disease-associated reported SNPs. Pathway analysis illustrated gene functions under normal and mutated conditions. Furthermore, haplotype and phylogenetic analysis of ASS1 (Argininosuccinate synthetase) gene were performed on study samples and NCBI retrieved sequences.

RESULTS

The study's focus was to screen the herds for prevalence of carriers of genetic disorders, as they are the main source of disease dissemination. One animal was found carrier for BC, whereas no carriers were found for BLAD and DUMPS. The protein models corroborated the reported amino acid change in BLAD, and protein truncation in both BC and DUMPS proteins. SNPs found in NCBI retrieved sequences were either silent or missense and had no effect on protein structure. DNA network presented graphical illustration of haplotype interactions and phylogenetic analysis conferred evolutionary landscape of ASS1 gene. The combination of these approaches produced an in-depth genetic picture of BC in Pakistani cattle.

CONCLUSION

The development of diagnostic tests and identification of the heterozygous BC sample underscores the significance of constant monitoring to avoid the unwanted dissemination of mutant alleles among Pakistani cattle, thereby promoting the general well-being and sustainability of the dairy sector.

Free radicals and antioxidants in inflammatory processes and ischemia-reperfusion injury

This article discusses the current understanding of the role of free radicals and antioxidants in inflammatory processes and in ischemia reperfusion injury. It begins by describing the manifestations of acute inflammation and outlining the cellular events that occur during inflammation. It then describes the biochemical mediators of inflammation with special attention to nitric oxide. It details the process of hypoxia reperfusion injury, the enzymes involved, its treatment, and studies involving specific hypoxia reperfusion injuries in various animal species.

Effectiveness of a program aimed at the elimination of BLAD-carrier bulls from Polish Holstein-Friesian cattle

The molecular basis of BLAD is the D128G mutation of the gene coding for the CD18 subunit of beta-2 integrin. This mutation is lethal, since homozygous (BL/BL) animals die before they reach sexual maturity. In the 1990s, BLAD was the most widespread genetic disease in HF cattle worldwide. The aim of the present study was to determine the frequency of BLAD carriers among 4645 young breeding bulls in Poland in 1995-2006. The frequency of carriers of the mutated allele showed a clear decreasing trend. The highest frequency (7.9%) was recorded while implementing the BLAD control program (1995-1997). Regular monitoring has enabled a great reduction of this threat to the tested population. Today only sporadic cases of BL/TL heterozygotes are reported (ca. 0.8% in 2004-2006).

Identification of a unique splice site variant in SLC39A4 in bovine hereditary zinc deficiency, lethal trait A46: An animal model of acrodermatitis enteropathica

Lethal trait A46, also known as bovine hereditary zinc deficiency, Adema disease, and hereditary parakeratosis, is an autosomal recessive disorder first described in 1964, with a clinical presentation similar to that of acrodermatitis enteropathica (AE) in humans. The molecular basis of the defect has not been previously identified. Recently, the basic defect in AE was found to lie in SLC39A4. We report the characterization of the bovine ortholog of SLC39A4 and identification of a unique splice site variant within this gene in affected animals. The mutation leads to exon skipping, leaving the coding region in frame. The gene product is predicted to lack two critical motifs, which lie in adjacent transmembrane domains implicated in the formation of a pore responsible for the transport of zinc. While further functional studies are warranted, this unique variant is likely to be responsible for the impaired zinc absorption in this disease.

Bovine Leukocyte Adhesion Deficiency (BLAD): A Review

Bovine leukocyte adhesion deficiency (BLAD) in Holstein cattle is an autosomal recessive congenital disease characterized by recurrent bacterial infections, delayed wound healing and stunted growth, and is also associated with persistent marked neutrophilia. The molecular basis of BLAD is a single point mutation (adenine to guanine) at position 383 of the CD18 gene, which caused an aspartic acid to glycine substitution at amino acid 128 (D128G) in the adhesion molecule CD18. Neutrophils from BLAD cattle have impaired expression of the beta2 integrin (CD11a,b,c/CD18) of the leukocyte adhesion molecule. Abnormalities in a wide spectrum of adherence dependent functions of leukocytes have been fully characterized. Cattle affected with BLAD have severe ulcers on oral mucous membranes, severe periodontitis, loss of teeth, chronic pneumonia and recurrent or chronic diarrhea. Affected cattle die at an early age due to the infectious complications. Holstein bulls, including carrier sires that had a mutant BLAD gene in heterozygote were controlled from dairy cattle for a decade. The control of BLAD in Holstein cattle by publishing the genotypes and avoiding the mating between BLAD carriers was found to be successful. This paper provides an overview of the genetic disease BLAD with reference to the disease in Holstein cattle.

PCR screening and allele frequency estimation of bovine leukocyte adhesion deficiency in Holstein and Gir cattle in Brazil

Bovine leukocyte adhesion deficiency (BLAD) is a disease known to affect the Holstein cattle breed throughout the world. Eighty-eight Holstein dairy cows and 88 Gir dairy bulls were genotyped by PCR for the CD18 BLAD alelle. The frequency of the BLAD mutant allele and the BLAD-carrier prevalence in Brazilian Holstein cows were 2.8 and 5.7%, respectively. No mutant allele was found in any of the 88 Gir animals. We conclude that the CD18 gene mutation is prevalent in Brazilian Holstein cattle and absent or present at a very low frequency in Gir cattle.

Prevalence and allele frequency estimation of bovine leukocyte adhesion deficiency (BLAD) in Holstein-Friesian cattle in Japan

Blood samples from 796 Holstein dairy cows in 20 herds from 6 districts in Japan from June 1994 to August 1995 were examined to determine whether they were BLAD-free, BLAD carriers, or BLAD-affected by use of DNA-polymerase chain reaction (PCR) analysis. The usage of semen of confirmed BLAD-carriers for artificial insemination in the Hokkaido district and two selected dairy farms was examined to estimate the gene frequency of BLAD carriers of sires. BLAD-carrier prevalence in 20 herds (796 cows, over 2.5 years old) ranged from 0 to 23.5%, and the mean BLAD-carrier prevalence was 8.1%. The BLAD-carrier prevalence in 10 herds (363 cows) in which the occurrence of BLAD was not detected by the DNA-PCR test ranged from 0 to 12.5% with a mean of 5.4%. The BLAD-carrier prevalence in 10 herds (433 cows) in which the occurrence of BLAD was confirmed by DNA-PCR analysis ranged from 2.6 to 23.5% with a mean of 10.8%, and these values were significantly (P < 0.05) higher than those of dairy herds in which the occurrence of BLAD was not detected. The age distribution in BLAD carriers in these cows ranged from 2.5 to 11 years. The mean gene frequencies of BLAD among 796 cows from 20 herds and 433 cows from 10 herds in which the occurrence of BLAD was detected were 0.041 and 0.054, respectively. The proportional usage of semen of BLAD carriers for artificial insemination in the Hokkaido district in 1992 was 12.6%, and its gene frequency was 0.058. On two selected farms in which higher BLAD-carrier rates were detected, the prevalences were 35.5% and 25.8%, and their gene frequencies were 0.177 and 0.129, respectively. The occurrence of BLAD-affected in Holstein dairy cattle was estimated to be 0.16-0.31% at birth in Japan without genetic control.

Bovine leucocyte adhesion deficiency: a review of a modern disease and its implications

Bovine leucocyte adhesion deficiency (BLAD) is a genetic disease of cattle which affects the hematopoietic system. In the last decade BLAD has become a disease of economic importance in the dairy industry. This review describes the chronological developments and thinking that led to the elucidation of BLAD as a disease distinct from previous models in canine and human populations. All species affected show signs of chronic and recurrent infections. Necrotic and/or gangrenous infections of soft tissues are prevalent, in addition to secondary infections with bacteria or fungi. Low birthweight and unthriftiness are key signs in all species affected by leucocyte adhesion deficiency (LAD). Dermatomycoses and impaired pus formation are also common findings. The physiological basis for BLAD is a deficiency in the chemotactic and phagocytic properties of leucocytes and particularly neutrophils. The inhibition of diapedesis in the inflammatory response prevents normal immune reactions to invading pathogens. Chronic infections are a consequence of the faulty immune mechanisms. The biochemical aetiology of BLAD involves cell surface glycoprotein molecules known as integrins. These are responsible for the cell-cell interactions necessary for neutrophils to adhere to vascular endothelium in a normal individual. Experiments with monoclonal antibodies to block LFA-1, Mac-1, and p150,95 (three integrins vital for cell-cell interactions) mimic BLAD symptomatology and have led to the discovery of the reciprocal intercellular adhesion molecule (ICAM). Through pedigree analysis and biochemical detection with restrictive endonucleases, BLAD has been isolated genetically to a single gene locus. The economic significance and prophylaxis of the disease are briefly discussed. In addition, the beneficial aspects of the study of BLAD are considered. There are advantages in producing a BLAD-like state for preventing transplant rejection, ischaemia-reperfusion injury and other problems arising from the deleterious effects of the inflammatory response.

An improved DNA test for bovine leucocyte adhesion deficiency

A modified DNA test, based on the polymerase chain reaction, was developed for the monogenic recessive disease bovine leucocyte adhesion deficiency (BLAD). The test was improved by the selection of new primers which facilitated the interpretation of the results. An easily scorable banding pattern makes the test useful in cattle breeding schemes and for clinical diagnosis. A total of 2381 samples was analysed over a period of three years. The carrier rate among young bulls at artificial insemination (AI) stations decreased from 11.6 per cent in 1993 to 9.9 per cent in the first five months of 1995. Continuous screening of young bulls before entering AI is still recommended unless both parents are proven to be genetically free of BLAD. The carrier rate among clinically suspect animals was not increased, and carriers are therefore not expected to be immunodeficient. Despite all efforts to eradicate the disease, calves with BLAD were still observed in 1995.

Investigations on the occurrence of hereditary diseases in the Danish cattle population 1989-1991

The methods of the Danish Bovine Genetic Disease Programme are outlined, and the results obtained during the first 3 years in function are described. The most common disease reported was spinal muscular atrophy in calves of the Red Danish Dairy breed with 312 reports. Necropsy was performed on 162 cases, and spinal muscular atrophy was diagnosed in 82 of these. Bovine progressive degenerative myeloencephalopathy, rectovaginal constriction, syndrome of arthrogryposis and palatoschisis, hereditary chondrodysplasia (2 different types), syndactylism, epitheliogenesis imperfecta, and osteogenesis imperfecta was diagnosed with 1 case each. Lethal trait A46 was diagnosed in 4 calves. Some of these diseases have not previously been described in Denmark, and epitheliogenesis imperfecta was for the first time diagnosed in the Hereford breed. Chromosome translocation 1/29 was detected in the Blonde d'Aquitaine (BAQ), Limousine, and Red Danish Dairy breed. The aberration occurred frequently in BAQ. Furthermore, a complex chromosome translocation t(1;8;9)(q45;q13;q26) was detected in the Red Danish Dairy breed.

Bovine leukocyte adhesion deficiency in Danish Holstein-Friesian cattle. II. Patho-anatomical description of affected calves

The patho-anatomical findings in 3 Danish Holstein-Friesian calves affected with bovine leukocyte adhesion deficiency (BLAD) are described. The diagnosis was confirmed by genotyping for the BLAD mutagene by polymerase chain reaction technique. The main clinical symptoms were general unthriftyness and leukocytosis with a high proportion of neutrophils. None of the calves suffered from severe infections and the major pathological changes were different from those described in previously published cases. One calf had a fibro-granulomatous perilienitis and calcification of splenic stroma and pulmonic arteries. In the other cases only minor pathological changes were present.

Investigations on the occurrence of hereditary diseases in the Danish cattle population 1989-1991

The methods of the Danish Bovine Genetic Disease Programme are outlined, and the results obtained during the first 3 years in function are described. The most common disease reported was spinal muscular atrophy in calves of the Red Danish Dairy breed with 312 reports. Necropsy was performed on 162 cases, and spinal muscular atrophy was diagnosed in 82 of these. Bovine progressive degenerative myeloencephalopathy, rectovaginal constriction, syndrome of arthrogryposis and palatoschisis, hereditary chondrodysplasia (2 different types), syndactylism, epitheliogenesis imperfecta, and osteogenesis imperfecta was diagnosed with 1 case each. Lethal trait A46 was diagnosed in 4 calves. Some of these diseases have not previously been described in Denmark, and epitheliogenesis imperfecta was for the first time diagnosed in the Hereford breed. Chromosome translocation 1/29 was detected in the Blonde d'Aquitaine (BAQ), Limousine, and Red Danish Dairy breed. The aberration occurred frequently in BAQ. Furthermore, a complex chromosome translocation t(1;8;9)(q45;q13;q26) was detected in the Red Danish Dairy breed.

Bovine leukocyte adhesion deficiency in Danish Holstein-Friesian cattle. II. Patho-anatomical description of affected calves

The patho-anatomical findings in 3 Danish Holstein-Friesian calves affected with bovine leukocyte adhesion deficiency (BLAD) are described. The diagnosis was confirmed by genotyping for the BLAD mutagene by polymerase chain reaction technique. The main clinical symptoms were general unthriftyness and leukocytosis with a high proportion of neutrophils. None of the calves suffered from severe infections and the major pathological changes were different from those described in previously published cases. One calf had a fibro-granulomatous perilienitis and calcification of splenic stroma and pulmonic arteries. In the other cases only minor pathological changes were present.