Effect of injectable trace mineral supplementation on peripheral polymorphonuclear leukocyte function, antioxidant enzymes, health, and performance in dairy cows in semi-arid conditions.

The objective of this study was to evaluate the effect of subcutaneous injections of 15 mg/mL Cu, 5 mg/mL Se, 60 mg/mL Zn, and 10 mg/mL Mn on health, performance, polymorphonuclear leukocyte (PMNL) function, circulating glutathione peroxidase (GPx) and superoxide dismutase (SOD) concentrations, and inflammation of dairy cows undergoing the transition period in high temperature-humidity index. A total of 923 multiparous cows from 2 commercial dairy farms were randomly allocated into 1 of 2 treatment groups as follows: control and injectable trace mineral supplementation (ITMS). Cows in the ITMS group received 7 mL of subcutaneous injections at dry-off (208 ± 3 d of gestation), 260 ± 3 d of gestation, and at 35 ± 3 d in milk (DIM). Data regarding health traits, reproductive performance, milk yield, and survivability were extracted from farm database software, and animals were followed-up until 300 DIM. For a subset of 142 cows from one herd, blood samples were collected at enrollment, and at 3 ± 1, 7 ± 1, 10 ± 1, and 35 ± 3 DIM to evaluate hematology, PMNL function, GPx and SOD concentrations, and circulating haptoglobin. Logistic regression was used to assess health and pregnancy per artificial insemination at first service. Cox proportional hazards models were used to evaluate hazard of pregnancy and culling. Mixed linear regression models accounting for repeated measures were used to assess all continuous variables collected over time. Parity, twinning, and previous gestation length were considered as potential confounders. Farm was included as a random effect. The ITMS cows tended to have lower incidence of metritis and stillbirth compared with control group. However, ITMS treatment did not influence the incidence of other diseases (e.g., mastitis, retained placenta), milk yield, reproductive performance, culling, and leukocyte count. Neutrophil-to-lymphocyte ratio, PMNL phagocytosis, and oxidative burst as well as intensity of the oxidative burst were greater for ITMS-treated cows in comparison to control cows. The ITMS cows had decreased expression of the adhesion molecule L-selectin on PMNL surface. The serum concentration of GPx and SOD were not affected by ITMS treatment. In conclusion, ITMS tended to reduce the incidence of metritis and stillbirth parturition, improved PMNL function, and improved the inflammatory status of dairy cows undergoing the transition period in high temperature-humidity index conditions. However, these findings did not translate into improved milk yield, reproductive performance, and survivability.

Effects of hydroxychloride sources of copper, zinc, and manganese on measures of supplement intake, mineral status, and pre- and postweaning performance of beef calves.

Our objective was to evaluate the effect of Cu, Zn, and Mn source on measures of 1) preferential intake of mineral-concentrated supplements and 2) mineral status and pre- and postweaning performance of beef calves. In Exp. 1, 4 trials were conducted to assess the effect of source of Cu (750 mg/kg; Trial 1), Zn (2,000 mg/kg; Trial 2), Mn (3,000 mg/kg; Trial 3), and all 3 elements (Trial 4) on preferential intake of mineral-concentrated supplements. Supplements differed only by source of Cu, Zn, and Mn, which included hydroxychloride (hydroxy), sulfate, and organic options. In each trial, the 3 supplements were simultaneously offered to 8 pens of early-weaned calves (2 calves/pen; 126 ± 8.0 kg average BW) for a 4-h period and preferential intake was determined. When offered the opportunity to select among 3 supplement options, calves consumed more ( < 0.001) supplement containing hydroxy vs. organic or sulfate sources of Cu (Trial 1), Zn (Trial 2), and Mn (Trial 3). In Trial 4, when all 3 elements were combined within a single supplement, calves almost exclusively selected ( < 0.001) the hydroxy vs. organic or sulfate sources (82.9, 10.4, and 6.7% of total supplement intake, respectively [SEM 3.16]). In Exp. 2, calves were supplemented at a rate of 114 g/calf daily for 84 d before weaning (2 calves/pasture; 10 and 12 pastures in yr 1 and 2, respectively). Supplements were formulated to contain no supplemental minerals (control); hydroxy Cu, Zn, and Mn; or copper sulfate, zinc sulfate, and manganese oxide (sulfate/oxide). Total supplement intake was greater ( = 0.01) for calves consuming the hydroxy vs. the sulfate/oxide sources of Cu, Zn, and Mn (9.0 vs. 7.2 kg [SEM 0.45]). Preweaning calf BW gain did not differ ( ≥ 0.15) among treatments; however, calves provided mineral-fortified supplements had greater ( = 0.003) liver concentrations of Co and Se and tended ( = 0.07) to have greater liver concentrations of Cu at weaning compared with the controls. Calves provided mineral-fortified vs. control supplements had greater ( ≤ 0.05) peak concentrations of ceruloplasmin and haptoglobin and less BW gain during in the 16-d postweaning period. These data demonstrate greater voluntary intake of mineral-concentrated supplements among calves offered hydroxy vs. sulfate or organic sources of Cu, Zn, and Mn. Preweaning mineral-fortified supplementation increased calf mineral status, heightened inflammatory responsiveness, and decreased BW gain during the immediate postweaning period.

Biodisponibilidade de fontes orgânicas e inorgânicas de zinco em ovinos / Bioavailability of organic and inorganic zinc sources in sheep

Compararam-se os efeitos de diferentes fontes e doses de zinco na dieta de ovinos Santa Inês sobre os níveis de zinco plasmático e de fosfatase alcalina. Foram utilizados 40 cordeiros, recém-desmamados, com média de peso de 18,4kg, distribuídos em 10 tratamentos: 1- dieta basal sem suplementação de zinco; 2- dieta basal + 200mg de Zn/kg de MS na forma de óxido de zinco; 3- dieta basal + 400mg de Zn/kg de MS na forma de óxido de zinco; 4- dieta basal + 600mg de Zn/kg de MS na forma de óxido de zinco; 5- dieta basal + 200mg de Zn/kg de MS na forma de zinco aminoácido; 6- dieta basal + 400mg de Zn/kg de MS na forma de zinco aminoácido; 7- dieta basal + 600mg de Zn/kg de MS na forma de zinco aminoácido; 8- dieta basal + 200mg de Zn/kg de MS na forma de zinco proteinato; 9- dieta basal + 400mg de Zn/kg de MS na forma de zinco proteinato; 10- dieta basal + 600mg de Zn/kg de MS na forma de zinco proteinato. A cada 28 dias, os animais foram pesados e tiveram seu sangue colhido para análise de zinco (Zn), análise de fosfatase alcalina e análises de imunoglobulinas G (IgG) e M (IgM). No final do experimento, foram coletadas amostras de fígado para estudo dos níveis de zinco hepático. Não houve diferença entre tratamentos nos níveis de fosfatase alcalina e de zinco hepático, e no ganho de peso (P>0,05), mas houve diferença (P<0,05) nos níveis de Zn plasmático e nos níveis de IgG e IgM. Baseando-se no acúmulo no fígado, a estimativa da biodisponibilidade de zinco, por intermédio das equações de regressão, mostrou que as fontes orgânicas e inorgânicas de zinco não diferiram entre si.

This research was done to compare the effects of different zinc sources and doses in the Santa Ines sheep diet. Forty lambs at weaning, with 18,4kg BW were randomly allotted and fed 10 treatments: 1- base diet without zinc supplementation; 2- base diet + 200mg Zn/kg of DM as zinc oxide; 3- base diet + 400mg Zn/kg of DM as zinc oxide; 4- base diet + 600mg Zn/kg of DM as zinc oxide; 5- base diet + 200mg Zn/kg of DM as amino acid zinc; 6- base diet + 400mg Zn/kg of DM as amino acid zinc; 7- base diet + 600mg Zn/kg of DM as amino acid zinc; 8- base diet + 200mg Zn/kg of DM as proteinato zinc; 9- base diet + 400mg Zn/kg of DM as proteinato zinc; 10- base diet + 600mg Zn/kg of DM as proteinato zinc. The animals were weighed and sampled for blood zinc analysis, phosphatase alkaline analysis and immunoglobulins G and M analysis. At the end of the experiment liver samples were collected to study the zinc hepatic levels. There was no difference in phosphatase alkaline levels, hepatic zinc levels and weight gain (P>0,05) but differences (P<0,05) in plasmatic zinc levels and in IgG and IgM levels were observed. Based on liver tissue uptake, estimates of the zinc bioavailability, through the regression equations showed that the organic and inorganic sources of zinc did not differ.