Use of Chlortetracycline for Treatment of New Feedlot Cattle3

Abstract

Two 56-d shipping fever trials of similar design were conducted the same season (fall) at Kansas State University (KSU) and at Purdue University (PU) to compare various levels of chlortetracycline (0 or 350 mg X head-1 X d-1 continuously or 1, 2 or 4 g X head-1 X d-1 for the first 14 d). Weanling crossbred steer calves were utilized (210 head of Angus X Simmental, averaging 197 kg, at KSU; 268 head of Angus X Hereford, averaging 192 kg, at PU). For the first 28 d in the KSU trial (October 13 to December 8), cattle that received 4 g X head-1 X d-1 the first 14 d gained more rapidly (P less than .05) than cattle fed 350 mg X head-1 X d-1 continuously or than the controls that received no chlortetracycline (CTC; 1.05 vs .92 or .93 kg/d, respectively). Cattle that received 4 g CTC X head-1 X d-1 for the first 14 d required less (P less than .05) dry matter per kg gain than steers that received 350 mg X head-1 X d-1 continuously over the 56-d period. In the PU trial (October 6 through December 1), all CTC treatments resulted in increased feed efficiency (P less than .05) over the controls through 28 d, and the 4 g X head-1 d-1 for 14 d and 350 mg X head-1 X d-1 continuously, improved feed efficiency over the other groups for the 56-d period.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of lasalocid and intermittent feeding of chlortetracycline on the growth of prepubertal dairy heifers

“…The researchers hypothesized that the selective bacteriostatic action of CTC resulted in more favorable bacterial flora within the gastrointestinal tract, thus improving overall health and increasing appetite. When newly received feedlot cattle were supplemented with CTC at a level of 350 mg/d, an increase in feed intake and subsequent growth rate were observed (Perry et al, 1986), an increase in feed efficiency was also observed (Duff et al, 2000). Unlike the aforementioned studies, no effect of CTC on DMI was observed in our study.…”

Effect of the Feed Additives Chlortetracycline, Monensin and Lasalocid on Feedlot Performance of Finishing Cattle, Liver Lesions and Tissue Levels of Chlortetracycline

“…Representative lesions were examined histologically. The chi-square test was used to assess the statistical significance of treatment effects (Steel and Torrie 1980 The results from this experiment are in agreement with data of Perry et al (1971Perry et al ( , 1986 which showed that nonstressed cattle also respond positively to CTC at subtherapeutic levels.…”

The Rumen Microbial Ecosystem

“…In animals fed high-forage diets, a major part of the recycled urea enters the gastrointestinal tract post-ruminally. In ruminants, subtherapeutic doses of antibiotics are used for the prevention of bacterial diarrhea, bacterial pneumonia and shipping fever, anaplasmosis, foot rot, vibrionic abortion, bacterial enteritis, and liver abscesses (Perry et al, 1986;Gallo and Berg, 1995). The suppression of bacterial ammonia production in the small intestine may be one of the mechanisms for the growth-stimulatory effects of antibiotics (Visek, 1978).…”