Characterization of ruminal acidosis and initial phase of laminitis inducted by oligofructose in crossbred calves

Abstract

RESUMO.-[Caracterização da acidose ruminal e da fase inicial da laminite induzidas por oligofrutose em bezerros mestiços.] Uma das formas de se estudar a laminite bovina é sua indução experimental por meio do fornecimento de grande quantidade de carboidrato de alta fermentação. O protocolo mais eficaz até o momento foi o uso de oligofrutose. Objetivou-se avaliar aspectos clínicos e histológicos dos dígitos de bovinos na indução experimental de acidose ruminal e laminite usando oligofrutose. Utilizaram-se seis bezerros mestiços (Bos taurus x Bos indicus) de um ano, divididos em Grupo I (GI) e Grupo II (GII). Os animais em GI e GII receberam oligofrutose por via intrarruminal nas doses de 13 e 17g/kg respectivamente. Os bovinos foram avaliados clinicamente por 28 horas e fragmentos de coroa e muralha abaxial dos dígitos foram ABSTRACT.-One of the ways to study cattle laminitis is its experimental induction by supplying a large amount of high fermentation carbohydrate. The most effective protocol until now has been the use of oligofructose. The objective of this study was to evaluate clinical and histological aspects of the hoof in experimental induction of ruminal acidosis and laminitis in calves using oligofructose. Six crossbred (Bos taurus x Bos indicus) yearling calves divided into Group I (GI) and Group II (GII) were used. Animals in GI and GII received intraruminal oligofructose in doses of 13 and 17g/kg, respectively. During 28 hours the calves were clinically evaluated and 30 hours after induction, samples were taken from coronary and abaxial wall of the hoof for histologic evaluation. Were noticed signs of ruminal and metabolic acidosis like rumen distension with fluid, diarrhea, ruminal pH reduction and, at blood gas analysis, pH and bicarbonate below reference range. Lameness was not observed however, some animals had a slower gait and apathy, possibly due to metabolic acidosis, though. Histologically, typical lesions of laminitis like circulatory changes and inflammatory infiltrate in the dermis, irregularities and areas of detachment at basement membrane and morphologic changes in cells from basal epidermis were found. The protocol induced, in the first 30 hours, clinical signs of ruminal and metabolic acidosis and low grade histologic lesions in the digits. Lameness and digit pain were not observed, characterizing the prodromic phase of the disease.

Characterization of Oligofructose-Induced Acute Rumen Lactic Acidosis and the Appearance of Laminitis in Zebu Cattle

“…The present study was successful in inducing laminitis in 93.1% of zebu animals, while Thoefner et al [19] reached 66.7% and Danscher et al [39] reached 100% in taurine cows. The histological findings are compatible with the inflammatory process, confirming the occurrence of laminitis, with similar features to those found by others Noronha Filho et al [36] and Danscher et al [28], with biopsies performed at 28 and 72 h, respectively.…”

“…Regarding blood gas variables, the decrease in blood pCO 2 at the peak of metabolic acidosis is noteworthy, interpreted as a clear respiratory compensation to metabolic acidosis, which was also observed by Noronha Filho et al [36].…”

Characterization of the Bacterial Community of Rumen in Dairy Cows with Laminitis

“…Lameness bovines were further examined by shoeing to identify laminitis. The diagnosis of laminitis, as previously described, and the scoring criteria are shown in Table 2 [ 25 ]. We chose the scores 2–4 in the present study.…”

Evaluation of infrared thermography, force platform and filmed locomotion score as non-invasive diagnostic methods for acute laminitis in zebu cattle

“…However, although the efficiency of this test is proven, it is important to emphasize that it is influenced by the force applied to the hoof, moisture, and hoof thickness [ 11 ]. This method has proven to be efficient in the identification of oligofructose-overload-associated laminitis [ 7 , 11 – 13 ].…”