Heifers

C25H32O4, an additive that is a synthetic progesterone, suppresses estms in heifers and results in increased weight gain and feed efficiency (5). 

Very Htfle data are available regarding effects of anaboHc steroid implants on the Hpid metaboHsm in growing mminants. Lipogenic enzyme activity and fatty acid synthesis in vitro were elevated in subcutaneous adipose tissue from bulls implanted with estradiol (44), which may account for the increase in fat content of carcasses reported in some studies. TBA implants have no effect on Hpogenesis in intact heifers, and only tend to reduce Hpogenic enzyme activities in ovariectomized heifers (45). 

Heifer, W., Die Tranen der Gotter, Jemen, Oman, V.A. Emirate, Merian, 59, 1996. Hahn-Deinstrop, E., Koch, A., and Muller, M., Guidelines for the assessment of the traditional herbal medicine Olibanum by application of HPTLC and DESAGA ProViDoc video documentation J. Planar Chromatogr., 11, 404, 1998. 

Bowen HJM (1965) A standard biological material for elementary analysis. In Shallis PW, ed. Proc of the SAC Conference, Nottingham, pp 25-31. W Heifer and Sons, Cambridge. 

Izard M.K. and Vandenbergh J.G. (1982a). Priming pheromones from oestrous cows increase synchronisation of estrous in dairy heifers after PGF-2a injection. J Reprod Fertil 66, 189-196. 

Heifer rearing is easier with a summer calving herd. Calves are usually strong and free of pneumonia, but the advantage with outdoor calving depends on the cleanliness and suitability of the available housing. 

Watson, D.L. (1992), Vaccination against experimental staphylococcal mastitis in dairy heifers . Res Vet Sci. London British Veterinary Association, Nov, 346-353. 

Roepstorff, A., Monrad, J., Sehested, J., Spegaard, K. and Danielsen, V. (2002). Mixed grazing with sows and heifers - as a mean of parasite control , in Novel Approaches Meeting III - A Workshop Meeting on Helminth Control in Livestock in the New Millenium. Third International conference, 1-5 July 2002, 41. 

Zearalenone (ZEA) is synthesised by many Fusarium species, which also produce DON, and is found worldwide in maize and maize products. Young sows seem to be the most susceptible animals and may show symptoms of hyperoestrogenism even with low ZEA intakes (0.06 mg/kg body weight intake). In contrast, 300 ppm are reported to be tolerated by hens and up to 2000 ppm by young heifers (Fink-Gremmels, 2005a). 

Faeces from colonised cows may contain from 102 to 107 colony-forming units (CFU) of Salmonella cells per gram of faeces. Particularly calves and heifers colonised with E. coli 0157 H7 may shed the bacteria at levels ranging from 102 to 105 CFU g 1 (Himathongham el al., 1999). Furthermore, calves younger than four months are the main domestic animals that excrete pathogenic protozoa like Giardia and Cryptosporidia. 

Famphur was not very effective in the control of ticks. The tropical horse tick (Anocentor nitens) is a species of serious concern to horse breeders and raisers in Florida mainly because it transmits Babesia caballi, the causative agent of equine piroplasmosis. A secondary concern is that heavy tick infestations may cause injury to the ears of the horse (Gladney etal. 1972). Data were unavailable on famphur control of ticks in horses however, famphur was 99.9 to 100% effective in controlling A. nitens in Hereford steers and heifers when fed in the diet at 5 mg/kg BW for 14 to 21 days. Famphur at 2.5 mg/kg BW in cattle diets for 7 days was only partially effective (39 to 87.5%) in controlling horse ticks (Gladney et al. 1972). Famphur — despite multiple treatments — was not effective in controlling cattle ticks (Haemaphysalis longicornis) when used as a pour-on at recommended application rates in weaned Hereford calves (Heath et al. 1980). 

Given to 180-kg heifer calves 12 days before infestation by 30-60-day-old larvae of ticks. Sustained release equivalent to 3, 5, or 6.8-10.1 mg famphur/kg body weight (BW) daily 7 mg/kg BW daily (range 4.5-11.5 mg/kg BW daily)... 

All doses inhibited erythrocyte cholinesterase levels by 45-95%. All groups tolerated 16.6 mg/kg BW. Severe toxicosis in the two high-dose groups (9 of 20) in bulls but not in heifers and steers 7 of the 9 bulls died or had to be euthanized necropsy showed severe pulmonary edema... 

Brahman bulls, steers, and heifers mean weight of 117 kg... 

Erythrocyte cholinesterase depression after 24 h was 43% in bulls and 33-34% in steers and heifers After 5 h, 1 of 13 bulls was anorexic and salivating After 48 h, erythrocyte cholinesterase depression was 56% in bulls, 55% in steers, and 51% in heifers 2 of 3 famphur-treated calves died... 

Bailey, P.J., W.A.D. Carroll, and B. Knee. 1984. Effects of lice infestation on the growth of beef heifers in Victoria. Austral. Jour. Exper. Agricul. Anim. Husbandry 24 140-143. 

Johnson, W.P., B.T. Alford, and J.J. Drain. 1972. Safety of famphur to young Brahman heifers, bulls and steers. Veterin. Med., Small Anim. Clin. 67 686. 

Teel, P.D., J.A. Hair, and L.G. Stratton. 1979. Laboratory evaluation of a sustained-release famphur bolus against Gulf Coast and lone star ticks feeding on Hereford heifers. Jour. Econ. Entomol. 72 230-233. 

O Gorman, J., F.H. Smith, D.B.R. Poole, M.P. Boland, and J.F. Roche. 1987. The effect of molybdenum-induced copper deficiency on reproduction in beef heifers. Theriogenology 27 265. 

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