Supplemental dietary chromium does not influence ACTH, cortisol, or immune responses in young calves inoculated with bovine herpesvirus-1.

Abstract

Twelve Holstein bull calves (6 to 8 wk of age) were used to determine the influence of supplemental dietary Cr on ACTH, cortisol, and immune responses of calves experimentally inoculated with bovine herpesvirus-1 (BHV-1). Calves supplemented with Cr received 3 mg Cr/d (Chromium, n = 6) of a high-Cr-yeast product. Following 53 d of treatment, all calves were fitted with jugular catheters, and blood samples were collected every 4 h into tubes containing ETDA. Twenty-four hours later, all calves were inoculated intranasally with BHV-1 (1 x 10(7) plaque-forming units in each naris). Serial blood collection continued at 4-h intervals for 6 d. Plasma was harvested, immediately frozen in liquid nitrogen, and stored at -20 degrees C. Individual rectal temperatures and urine samples were collected at the same time each day. Rectal temperatures were elevated (P < .05) on d 2, 3, 4, and 5 but were not affected by Cr treatment. Treatment with Cr did not affect secretion of ACTH, cortisol, or plasma tumor necrosis factor-alpha, although clear circadian variation in ACTH and cortisol occurred. No differences were detected in the concentrations of trace minerals excreted daily in the urine, lymphocyte proliferative response to mitogen stimulation, and neutrophil bactericidal function. The acute phase proteins, ceruloplasmin and fibrinogen, also were not affected by treatment or viral challenge. These data suggest the Cr supplementation using high-Cr yeast (3 mg/d) did not alter stress responses of calves experimentally inoculated with BHV-1.

Chromium improves production and alters metabolism of early lactation cows in summer

“…The similar serum cortisol concentrations were consistent with other reports under normal environments (Arthington et al, 1997; Kegly et al, 1997). Cortisol antagonizes insulin and prevents glucose entry into peripheral cells to spare it for use by tissues of greater demand (National Research Council, 1997).…”

“…Changes in circulating cortisol can usually be a useful indicator of short‐term stresses, but seemingly not as much reliable to indicate chronic stresses. Chromium may decrease cortisol to progesterone ratio likely by reducing the activity of 11‐β‐hydroxylase, responsible for progesterone conversion to cortisol (Mertz, 1993; Arthington et al, 1997). The absence of treatment effects on serum cortisol and ‘cortisol:progesterone’ suggests that cows were not exposed to sever changes in the degree of stress.…”

The effect of different levels of organic and inorganic chromium supplementation on immune function of broiler chicken under heat-stress conditions

“…This is a typical metabolic relationship between insulin (anabolic) and corticosterone (catabolic), in which they have opposite effects on metabolism. In contrast, Kegley et al [42] and Arthington et al [43] did not detect similar effects on cortisol levels. A Cr deficiency can disrupt the metabolism of carbohydrates and protein and reduce insulin sensitivity in peripheral tissues [44,45].…”

Desempenho Produtivo E Reprodutivo De Ovelhas Santa Inês Suplementadas Com Cromo Orgânico Durante a Estação De Monta E a Gestação

“…A efetividade da inclusão dietética do Cr esta diretamente relacionada ao tipo, a duração e a intensidade do estresse a que os animais são expostos (Arthington et al, 1997). No presente estudo, durante os meses iniciais do experimento (entre os meses de janeiro a março), o clima propiciou condições severas de estresse, principalmente devido a alta umidade relativa do ar, bastante acima dos níveis de conforto (UR = 30%) referidos por Marai et al (2007) (Tabela 2).…”