Naturally monozygotic quadruplets in a Braford cow confirmed by DNA analysis: A case report

Cattle are a monotocous species, despite naturally conceived multiple births are sometimes observed. Although the number of twins has consistently increased, triplet and quadruplet pregnancies represent 0.015% and 0.004% of the total births, respectively. Multiple births are the result of multiple ovulation and/or the spontaneous cleavage of one fertilized oocyte, which is known as monozygotic (MZ) twinning. In cattle, approximately 5% to 14% of all twin births are MZ, and births with more than two MZ calves are extremely rare. Monozygotic animals are genetically identical, and those derived from two or more zygotes are genetically different. Furthermore, the presence of placental vascular anastomosis can result in foetal chimerism. Notwithstanding, animals born as single calves can be chimeras when one of the foetal twins dies undetected in utero. Here, we used DNA testing to study the zygotic condition of an unusual female quadruplet born from a Braford cow bred in a multi-sire natural mating system without hormone stimulation. Two tissues with different embryological origin were sampled to test zygosity and possible chimerism. The results showed an identical genotype, confirming they all originated in an MZ pregnancy and suggesting the lack of chimerism in all animals. The use of MZ twins in breeding and selection systems provides an alternative to the conventional progeny testing. Some works have suggested a genetic background of MZ twins in humans. This female and her daughters could be the founders of a lineage to study the possible inheritance of MZ multiple births in cattle.     

Atypical actinobacillosis affecting hind limbs and lungs in a single beef cattle herd

Actinobacillosis usually is a sporadic infection that affects the tongue in cattle (“wooden tongue”) with possible spread to the digestive tract. Two 4‐year‐old Rouge‐des‐Prés cows from a single French beef herd were referred for chronic (2‐6 months) swelling and cutaneous nodules in the distal hind limbs. In addition to cutaneous signs, physical examination disclosed cachexia, lameness, lymphadenitis of the hind limbs, and pneumonia in both cows. Cytologic examination of direct skin smears was inconclusive, and no parasites were observed in examination of multiple skin scrapings. Histopathological examination of skin and lung biopsy specimens identified chronic, diffuse, severe pyogranulomatous dermatitis, associated with Splendore‐Hoeppli phenomenon and intralesional Gram‐negative bacteria. Cultures from skin, lymph nodes, and lungs (both cows were euthanized for welfare reasons) identified a Pasteurellaceae organism, confirmed as Actinobacillus lignieresii by partial sequencing of the rpoB gene. This report emphasizes that actinobacillosis can appear as a small outbreak in cattle with cutaneous and respiratory signs.     

我国奶牛磷需要量

饲喂奶牛应该满足而不是超过其营养需要量。给奶牛饲喂过量的磷会降低磷的利用率,增加磷向外围环境的排泄,从而造成严重的环境污染问题。降低奶牛日粮中磷的含量将减少磷的排泄和土壤中磷的蓄积,同时降低了生产成本,节约了不可再生的磷矿资源。     

An unusual epizootic of actinobacillosis in dairy heifers.

Actinobacillosis developed in a group of 52 Holstein-Friesian replacement heifers. They were confined to 4 pens in a barn. Cervical abscesses were first observed by the owner in 1 heifer a month after the heifers were fed chopped haylage that was particularly dry, tough, and stemmy. During the weeks that followed, morbidity reached 73% in heifers given the feed. Calves up to 4 months old were not given the haylage and did not develop the disease. Standard bacteriologic methods were used to identify Actinobacillus lignieresii from exudate of abscesses. A biopsy of superficial granulomatous tissue of the lips revealed fibers thought to be of plant origin. Affected cattle recovered in 3 to 6 months. The lesions of 3 cattle given sodium iodide intravenously and of 4 given streptomycin regressed sooner than those given penicillin or no treatment.     

An atypical lymphoma of T-cell lineage in the thorax of an aged cow.

An aged beef cow was presented for signs of thoracic disease. A complete clinical and diagnostic workup suggested neoplasia. Postmortem examination revealed a lymphoma of T-cell lineage confined solely to the thoracic cavity, predominantly in lung tissue. The diagnosis was based on light and electron microscopy, immunohistochemistry, and negative bovine leukemia virus and bovine immunodeficiency virus results.     

An atypical case of Trypanosoma cruzi infection in a young English Mastiff

A case of Trypanosoma cruzi infection in a young English Mastiff from Texas is presented. Clinical signs and laboratory findings included subcutaneous edema, lymphadenopathy, weight loss, and hypoalbuminemia. Cytology of a lymph node revealed numerous amastigotes. No trypomastigotes were observed in buffy coat preparation of peripheral blood, and on histologic evaluation, most organs contained numerous interstitial pseudocysts. Initial serology was positive for both T. cruzi and Leishmania, and immunohistochemistry supported a diagnosis of Leishmania. However, additional serology supported a T. cruzi infection, and cultivation of organisms isolated from a lymph node revealed morphology consistent with T. cruzi. In addition, PCR analysis resulted in a 504 bp fragment with 99% homology to a flagellar protein of T. cruzi. Although uncommon, autochthonous cases of both T. cruzi and Leishmania have been reported in the United States. Clinical signs observed with both diseases can show many similarities, cytology may be indistinguishable, as in this case, and serological cross-reactivity is common. This case demonstrates an unusual presentation of T. cruzi and the use of multiple testing strategies to support its diagnosis.     

朊蛋白在奶牛生殖系统表达的定位

用免疫组织化学方法对奶牛生殖系统中朊蛋白进行定位研究,结果表明:在雌奶牛卵巢、子宫阜、子宫呈阳性,输卵管呈弱阳性。雄奶牛睾丸、附睾呈现弱阳性,其他器官为阴性。这说明在这些组织中有正常的PrP存在,为探索Prion致病机理、感染途径提供基础数据,也为朊病毒是否可以垂直传播提供了基础数据。     

A case of abomasal displacement in a cow

Extract

Subject: Three-year-old Friesian cow, 19 days post-partum.