Relationships between maternal and fetal liver copper, iron, manganese, and zinc concentrations and fetal development in California Holstein dairy cows.

Associations between maternal trace element deficiencies and abortion have been made for many mammalian species. Objectives of this study were to estimate and correlate maternal and fetal hepatic Cu, Fe, Mn, and Zn concentrations through gestation. Additionally, aborted fetuses, stratified by cause of abortion (infectious or noninfectious), were compared to size-matched nonaborted fetuses to examine for magnitude and direction of change in hepatic trace element status. Dam and fetal liver were removed at slaughter from 103 Holstein dairy cows judged grossly normal by ante- and postmortem examination. Liver samples were collected from fetuses submitted by veterinarians for routine diagnosis of abortion (n = 80). Hepatic Cu, Fe, Mn, and Zn concentrations were determined by flame spectrophotometry. Comparisons of groups, estimations of correlations, and derived prediction equations were made by least-squares methods. Maternal liver Cu, Fe, Mn, and Zn concentrations did not vary during gestation. Compared with the dam, fetal liver Fe and Zn concentrations were higher (P < 0.05), fetal Cu concentrations were similar (P > 0.05), and fetal liver Mn concentrations were lower (P < 0.05). As fetal size increased, fetal liver Cu and Zn concentrations increased (P < 0.05), fetal liver Fe concentration decreased (P < 0.05), and fetal liver Mn did not change (P > 0.05). Aborted fetuses had lower liver Cu, Mn, and Zn concentrations than did nonaborted fetuses (P < 0.05). Liver Fe concentration was lower in aborted fetuses than in nonaborted fetuses in the second trimester only (P < 0.05). Consistently lower liver Cu, Fe, Mn, and Zn concentrations in aborted fetuses suggest a nonspecific change in trace element status, which implies an effect of abortion, not a cause of abortion.

Associations among prostaglandin F2alpha, plasma zinc, copper and iron concentrations and fetal loss in cows and mares.

The objective of this study was to test the hypothesis that PGF2alpha is associated with abortion and changes in plasma Zn, Cu, and Fe concentrations in cows and mares in their first trimester of pregnancy. Eleven pregnant cows were infused with endotoxin (n = 5) or endotoxin plus an inhibitor of cycloxygenase, flunixin meglumine (n = 6). Blood was collected over a 5-d period. Additionally, 4 mares were treated every 24 h with cloprostenol sodium and blood was collected hourly until abortion. Plasma Zn, Cu, and Fe were determined. Three of five cows treated with endotoxin aborted, but none of the six cows treated with endotoxin and flunixin meglumine aborted. Aborting cows had lower plasma Zn (P = 0.048) over the 5-d study period compared with the nonaborting cows. The changes in Zn corresponded to release of PGF2alpha. All 4 mares aborted and plasma Zn concentrations were lower (P = 0.008) and Cu/Zn was higher (P = 0.02) 12 h after cloprostenol treatment. Plasma Zn may be a useful biomarker for risk of spontaneous abortion, and the decline in plasma Zn may be caused by PGF2alpha.

Hemochromatosis in Salers cattle.

Two 2-year-old Salers cattle from different herds raised on pasture were evaluated for retarded growth and diarrhea. Increase of liver enzyme activities and prolonged sulfobromophothalein (BSP) half life (T1/2) indicated liver disease with impaired liver function. Histopathologic examination of liver biopsies revealed a micronodular cirrhosis with marked deposition of hemosiderin in hepatocytes, Kupffer cells, and arterioles. Transferrin saturation (TS) and liver iron content were markedly increased, consistent with a diagnosis of hemochromatosis. Both animals were euthanatized due to deterioration in their condition. Necropsy findings included hepatomegaly and hemosiderin accumulation in the liver, lymph nodes, pancreas, spleen, thyroid, kidney, brain and other glandular tissue. Continued surveillance of the second herd (serum iron, total iron binding capacity [TIBC], unsaturated iron binding capacity [UIBC], and TS), identified a heifer as a hemochromatosis suspect in a subsequent generation. Liver biopsies from that animal revealed the same histopathologic changes as the previous 2 animals, and similar increases in liver iron content (8,700 ppm, normal range 45 to 300 ppm). The 3 affected cattle were all products of line breeding programs and shared a common ancestor. The absence of dietary iron loading in conjunction with the histopathologic and metabolic findings were consistent with a diagnosis of primary hemochromatosis. The reported disease is similar to idiopathic hemochromatosis in human beings in which there is a hereditary defect in iron metabolism.

Growth of Holstein calves from birth to 90 days: the influence of dietary zinc and BLAD status.

The main objective of this study was to describe Holstein neonatal growth and development as influenced by dietary zinc supplementation and the CD18 genotype, both of which may affect immune competence. Holstein calves (n = 421), after being fed colostrum, were brought to a calf facility, randomly assigned to one of four zinc supplementation groups (control at 40 mg Zn/kg DM or the control diet supplemented with an additional 60 mg Zn/kg DM provided as either zinc sulfate, zinc lysine, or zinc methionine), weighed, and measured for morphometric growth parameters. Measurements were repeated at 30, 60, and 90 d. Calves were also genotyped for the presence of the mutant D128G CD18 allele, which, if present in two copies, causes bovine leukocyte adhesion deficiency. Zinc supplementation above 40 mg Zn/kg DM, regardless of the chemical form, did not accelerate growth (P > 0.25). Further, overall calf growth performance was not suppressed or improved (P > 0.4) in calves heterozygous at the CD18 locus relative to calves homozygous for the normal CD18 allele, although genotype negatively affected some morphometric measurements (P < 0.05). Using these data, quadratic models of early growth were generated as a preliminary step to develop growth criteria that will allow producers, veterinarians, and animal scientists to identify poor growth performance early in neonatal life. Such criteria provide the basis for tools to improve economic performance.

Economic losses from an episode of zinc toxicosis on a California veal calf operation using a zinc sulfate-supplemented milk replacer.

An episode of zinc toxicosis in 95 veal calves caused $29,602 in losses to the producer ($315/affected calf), most of them direct, out-of-pocket losses. Increased calf mortality and increased veterinary service costs accounted for a majority (70%) of the losses. Reduction of losses may have been accomplished by removing the source and increasing the roughage content in the diet, or by shipping the animals for immediate slaughter. Given the magnitude of the financial loss, especially those associated with calf mortality, it was concluded that producers should refrain from using large amounts of mineral supplements unless a deficiency has been diagnosed.

An epidemiologic study of mortality in veal calves subsequent to an episode of zinc toxicosis on a California veal calf operation using zinc sulfate-supplemented milk replacer.

Ninety-five 3- to 6-month old male Holstein veal calves were evaluated after an episode of zinc toxicosis, to describe clinical signs and to identify management and/or host-related factors that may have contributed to death. Clinical signs appeared 23 days after feeding of milk replacer commenced. Of 85 calves examined, 64 had pneumonia (75.5%), 62 had ocular signs (72.9%), 46 had diarrhea (54.1%), 34 were anorectic (40.0%), 15 were bloated (17.6%), 8 had cardiac arrhythmias (9.4%), 3 had convulsions (3.5%), and 3 were polydipsic/polyphagic (3.5%). Clinical signs began to appear when calves each were being fed approximately 1.5 to 2.0 g of zinc/day and exposed to a cumulative zinc intake of 42 to 70 g, from a milk replacer containing 706 micrograms of elemental zinc/g of milk replacer. Of 95 calves studied, 1 died before zinc was supplemented, 16 died during the episode, 12 were euthanatized, 1 was lost to follow-up evaluation, 1 was culled, and 64 were slaughtered. Deaths attributable to zinc toxicosis were observed between 25 and 53 days after the milk replacer was supplemented with zinc. Calves died while being exposed cumulatively to 30 to 66 g of zinc. The factors of previous pneumonia severity, age, cumulative daily exposure to zinc, and calf location within a bay were examined for possible associations with mortality, using stepwise logistic regression. Though younger calves tended to have a higher mortality than older calves, neither age category nor severity of pneumonia, before zinc supplementation, accounted for a significant mortality.(ABSTRACT TRUNCATED AT 250 WORDS)

Trace element deficiencies in cattle.

Deficiency of cobalt, copper, iron, iodine, manganese, selenium, or zinc can cause a reduction in production. Reduced production occurs most commonly when a deficiency corresponds to the phases of growth, reproduction, or lactation. Because of environmental, nutrient, disease, genetic, and drug interactions, deficiencies of single or multiple elements can occur even when the levels recommended by the National Research Council for these nutrients are being fed. Additionally, random supplementation of trace elements above National Research Council recommendations is not justified because of the negative interaction among nutrients and potential toxicosis. Evaluation of trace element status can be difficult because many disease states will alter blood analytes used to evaluate nutrient adequacy. Proper dietary and animal evaluation, as well as response to supplementation, are necessary before diagnosing a trace element deficiency.

Vitamin deficiencies in cattle.

Deficiencies of vitamins A, D, K, E and thiamin can cause severe limitations in beef production. In particular, vitamin A and E can be common causes of lost profit, secondary to limitations of reproductive and growth potential. Prolonged dry periods will reduce available A and E in pasture forage, as can ensiling and prolonged storage of harvested feedstuffs. Polioencephalomalacia is a thiamin responsive disorder, associated with high concentrate feeding and lush pastures. Antimetabolites, such as amprolium, will cause thiamine deficiency when fed in excess. Recent information has shown improved performance with supplemental beta carotene and niacin. The positive responses in reproductive performance, noted with cattle fed supplemental beta carotene, was independent of vitamin A. Supplementation of vitamins above National Research Council recommendations can be justified. However, proper evaluation of feed and animal status, and documentation of a response to supplementation is necessary before diagnosing deficiencies of specific nutrients.

Preliminary investigation of cardiac troponin I concentration in cows with common production diseases.

BACKGROUND: Increased cTnI concentrations are associated with adverse outcomes in humans and animals. Limited information is available on the prognostic value of cTnI in cows. OBJECTIVE: To measure cTnI in cows with noncardiac diseases and evaluate the association of cTnI concentration with adverse outcomes such as death or early removal from the herd. ANIMALS: Thirty control and 53 diseased cows. METHODS: Serum cTnI concentrations were determined with a point-of-care immunoassay. Cows were diagnosed ante- or postmortem with metritis (n = 6), mastitis (n = 4), peritonitis (n = 6), LDA (n = 14), LDA and metritis (n = 4), pneumonia (n = 6), dystocia requiring cesarean section (n = 5), and downer cow syndrome (n = 8). Animal survival was determined for up to 2 months after presentation. RESULTS: The immunoassay showed reliability for the detection of bovine cTnI. Cows with LDA and metritis (P < .05), peritonitis (P < .05), LDA (P < .001), dystocia requiring cesarean section (P < .01), and downer cow syndrome (P < .001) had higher cTnI concentrations than control cows. The odds of a negative outcome (death or culling) for cows with cTnI concentrations of ≥ 0.05, ≥ 0.1, ≥ 0.2, and ≥ 0.5 ng/mL were 2.4, 2.9, 4.8, and 6.2, respectively. CONCLUSION: Cows with noncardiac diseases may have some degree of myocardial injury. The magnitude of cTnI increased may assist clinicians in evaluating the risk of an adverse outcome and help guide decision-making regarding treatment and prognosis.

Validity and reliability of the St. George's Respiratory Questionnaire in assessing health status in patients with chronic pulmonary aspergillosis.

BACKGROUND: Chronic pulmonary aspergillosis (CPA) markedly reduces lung function through progressive lung destruction. To date, however, health status in patients with CPA has not been studied. This is due, in part, to a lack of adequately validated scales. The St. George's Respiratory Questionnaire (SGRQ) is widely used for several chronic respiratory diseases, but not for CPA. We examined the reliability and validity of SGRQ in CPA. METHODS: Eighty-eight patients with CPA completed the SGRQ, the Short Form-36 Health Survey (SF-36), and the Medical Research Council (MRC) dyspnea scale. Lung function and BMI were also measured. Pearson correlation, t test, analysis of variance, and their equivalents for nonparametric data and multivariate linear and binary analyses were used. RESULTS: The SGRQ components (symptoms, activity, and impact) and total scores achieved high internal consistency (Cronbach α = 0.77, 0.91, 0.86, and 0.94), and SGRQ components had good intercorrelation (r ≥ 0.41; P < .001) and correlated well with the total score (r ≥ 0.63; P < .001). There were high, intraclass, correlation coefficients for the total SGRQ and its dimensions (≥ 0.92). The SGRQ scores showed significant correlation with the MRC dyspnea scale and SF-36 components and differentiated between all grades of shortness of breath and different bands of disease severity (P < .05). In addition, patients with greater clinician-rated disease severity had more impairment of health status (P < .006). CPA severity was independently associated with impairment in health status, and COPD comorbidity significantly affected the health status in patients with CPA. CONCLUSIONS: SGRQ demonstrated a significant level of reliability and validity in measuring health status in CPA.

Biological markers of neonatal calf performance: the relationship of insulin-like growth factor-I, zinc, and copper to poor neonatal growth.

Raising a heifer calf to reproductive age represents an enormous cost to the producer. Poor neonatal growth exacerbates the costs incurred for rearing, and use of blood variables that may be associated with poorly growing calves may offer predictive value for growth and performance. Thus, the principal objective of the present study was to describe changes in serum IGF-I, zinc, and copper from birth to 90 d in Holstein calves, while accounting for sex and twin status, in poorly growing calves and calves growing well. A second objective was to test the hypothesis that an association exists between these serum variables and morphometric indicators of growth. Measurements of BW, length, and height were recorded at birth and at 30, 60, and 90 d of age. Jugular blood (12 mL) was collected from each calf on d 1 to determine serum total protein, serum IgG, packed cell volume, serum zinc, serum copper, serum IGF-I, and CD18 genotype for bovine leukocyte adhesion deficiency; serum zinc, serum copper, and serum IGF-I (predictor variables) were also determined for each calf on d 2 through 10 and on d 30, 60, and 90. Stepwise multiple regression and logistic regression analyses were used to examine the relationships between the predictor variables and the dependent variables (BW, height, and length at d 30, 60, and 90 of life). Birth weight, sex, serum IGF-I (at all ages), serum copper, and the serum copper-to-zinc ratio were associated, to varying degrees, with the dependent growth variables. Birth weight was consistently the dominant predictor. In conclusion, these results suggest that lighter birth weight, reduced serum IGF-I, and inflammation may be important causes of poor growth in neonatal Holstein dairy calves.

Laboratory-based surveillance of patients with bacterial meningitis in Egypt (1998-2004).

Laboratory-based surveillance for bacterial meningitis was conducted in a network of infectious disease hospitals in Egypt to better understand the epidemiology of this infection. Healthcare and laboratory personnel were trained in basic surveillance and microbiologic processing of cerebrospinal fluid (CSF) specimens. All bacterial isolates from CSF were confirmed and tested for antimicrobial susceptibility. PCR testing was performed on a random subset of purulent, culture-negative CSF specimens. Of 11,070 patients who met criteria for the case definition, 843 (8%) were culture positive (42% positive for Streptococcus pneumoniae, 20% for Haemophilus influenzae serotype b, 17% for each of Neisseria meningitidis and Mycobacterium tuberculosis, and 6% for other bacteria). Of 1,784 (46%) CSF specimens tested by PCR, 232 (13%) were positive for the first three major pathogens. Of N. meningitidis isolates, 52% belonged to serogroup A, 35% to serogroup B, and 4% to serogroup W135. S. pneumoniae isolates comprised 46 different serotypes, of which 6B, 1, 19A, 23F, and 6A were the most predominant. The overall case-fatality rate for culture-positive cases was 26% and was highest among patients with M. tuberculosis (47%). Factors significantly associated with death (p < 0.05) included admission to rural hospitals, long prodromal period, referral from other hospitals, antibiotic treatment prior to admission, and clear CSF (<100 cells/mm3). Susceptibility to ampicillin and ceftriaxone was observed in 44 and 100% of H. influenzae serotype b isolates and in 52 and 94% of S. pneumoniae isolates, respectively. This surveillance highlights the significant mortality and morbidity associated with bacterial meningitis in Egypt. Decision makers need to review current treatment guidelines and introduce appropriate vaccines for prevention and control of the disease.

Zinc intake, zinc status and growth in a longitudinal study of healthy Danish infants.

Mild, growth-limiting zinc deficiency might be prevalent in otherwise healthy infants according to recent studies. We examined zinc intake and status in 91 healthy term infants from birth to 12 months, as part of the Copenhagen Cohort Study on Infant Nutrition and Growth. Zinc intake was recorded monthly and the amount of zinc absorbed was estimated. These estimates were below recently published FAO/WHO/IAEA values for basal requirements in 68%, 62% and 14% of the infants at 2, 4 and 9 months of age, respectively. Serum zinc decreased significantly (p < 0.01) from 10.6 mumol/l at 6 months to 8.4 mumol/l at 9 months of age (normal range 10-18 mumol/l). Erythrocyte metallothionein values, a tentative indicator of long-term zinc status, decreased significantly from 2 to 6 months (p < 0.001) and from 6 to 9 months (p < 0.01). Serum zinc at 9 months was positively associated with growth velocity during the period from 6 to 9 months (weight: p = 0.05; knee-heel length: p = 0.002). The results provide descriptive data on zinc intake and zinc status in healthy Danish infants. Although some of our data suggest suboptimal zinc status during late infancy, evidence for this can only be obtained through a randomized intervention study.

Serum zinc and copper concentrations in relation to spontaneous abortion in cows: implications for human fetal loss.

The purpose of this study was to investigate the effect of the status of dietary zinc and serum zinc and copper concentrations on the risk of fetal loss in 570 cows. three herds received no supplements (herds 1, 3, 4), while cows in herd 2 received supplements of either 7 g zinc week-1 (n = 118), as zinc methionine, or a control diet containing methionine (n = 128). Serum zinc, copper and metallothionein concentrations were determined once a month throughout gestation. Logistic regression and survival analysis were used to examine for associations between risk of fetal loss and serum zinc, copper, copper:zinc, or metallothionein concentrations, supplement level, and maternal age at conception. The risk of fetal loss increased when both serum zinc decreased and copper concentrations increased (P < 0.0001; relative risk = 10.28, 95% confidence intervals = 4.69, 22.5). The attributable risk, for a decline in the zinc concentration by 10 mumol l-1 and an increase in the copper concentration by 5 mumol l-1 was 90.27%. Methionine-supplemented cows had a higher risk of fetal loss compared with zinc-methionine-supplemented cows (one-tailed P = 0.0375; relative risk = 2.98). Cows in herds 1, 3 and 4 had a higher risk for abortion than did zinc-methionine-supplemented cows in herd 2 (relative risk = 26.27, 95% confidence intervals = 2.31, 299.38; relative risk = 40.87, 95% confidence intervals = 3.50, 458.43; relative risk = 41.53, 95% confidence intervals = 3.77, 457.02, respectively). Our results suggest that inflammation and zinc nutriture may play an important role in fetal loss in dairy cows.

A pathologic and toxicologic evaluation of veal calves fed large amounts of zinc.

Tissues were examined from 26 male Holstein veal calves given large amounts of dietary zinc. All calves had been fed 706 micrograms zinc/g of milk replacer for 28 days before the first death occurred. Calves died naturally (14, group A) or were euthanatized (12, group B) after 23 days of feeding a lower concentration of zinc (150 micrograms/g). Average amounts of zinc in liver (wet weight) were 345.72 micrograms/g (group A) and 344.84 micrograms/g (group B). Mean kidney zinc concentrations were 219.0 micrograms/g (group A) and 252.38 micrograms/g (group B). Tissue manganese, copper, and iron levels were normal. Changes at necropsy included pneumonia, fluid digesta, and petechiae and infarcts in liver, kidney, and heart (as a result of bacterial infections). Histological changes that were directly attributed to dietary zinc intake were: marked atrophy and necrosis of pancreatic acinar tissue (group A); multifocal fibrosis of pancreatic acini (group B); multifocal renal cortical fibrosis with necrosis in convoluted tubules and loops of Henle, and with intratubular mineralization (groups A and B). Hepatic midzonal mineralization and fibrosis of the adrenal zona glomerulosa were seen in group B calves.

Effect of infant formula zinc and iron level on zinc absorption, zinc status, and immune function in infant rhesus monkeys.

To evaluate the effects of marginal zinc (Zn) deficiency on Zn absorption and metabolism, three groups of infant rhesus monkeys (n = 4/group) were fed from birth to 5 months of age either a regular infant formula (5 mg Zn/L) or a low-Zn formula (1 mg Zn/L). Since iron (Fe) intake may affect Zn absorption, the low-Zn formula was given without (1 mg Fe/L) or with Fe fortification (12 mg/L). At monthly intervals, Zn absorption and retention were assessed by gavage feeding with 65Zn and whole-body counting immediately after and on days 4, 7, and 11 after intubation. Blood samples were drawn before dosing for analyses of various potential markers of Zn status. Infants fed low-Zn formula had lower weight gain than controls; however, length growth was similar in all groups. 65Zn retention was considerably higher in both groups fed low-Zn formula (40%) than in the control group (20%), whereas plasma Zn levels were normal in all infants. Plasma metallothionein levels were generally very low and detectable in only 5 samples of 48; however, 4 of these were found in control infants. Neutrophil chemotaxis assessed at the end of the study was impaired in low-Zn infants compared to controls. In addition, low-Zn infants had increased levels of interleukin-2 at the end of the study. No differences were seen between the groups in hemoglobin levels, total white blood cells/absolute neutrophil counts, or plasma activities of 5'-nucleotidase or angiotensin converting enzyme. In conclusion, marginal Zn intake in infant rhesus monkeys resulted in increased Zn retention, which was not enough to completely compensate for the lower Zn intake. The higher level of iron fortification studied did not affect Zn retention significantly.

Role of eicosanoids in abortion and its prevention by treatment with flunixin meglumine in cows during the first trimester of pregnancy.

Intravenous infusion of E. coli endotoxin at a rate of 4.16 ng/kg/min over 6 hr (total dose 1.5 micrograms/kg) in 5 cows in the first trimester of gestation induced abortion between 60 and 72 hr in three cows. Plasma PGF2 alpha levels in the aborting cows increased significantly to 289% of the zero time control (ZTC) at 1 hr and remained elevated for 9 hr. The PGF2 alpha level remained unaffected in the non-aborting cows except at 2 hr. The plasma TxB2 levels were increased by 6 to 18 fold for 6 hr in both the aborting and non-aborting cows relative to their ZTC controls. The 6-keto-PGF1 alpha levels were significantly increased to 2 to 3 fold only in the aborting cows. Plasma cortisol levels were increased maximally to 1,500% of ZTC at 5 hr in the aborting cows. Thereafter, the levels gradually declined but remained significantly elevated for 24 hr. The increases in the cortisol levels in the non-aborting cows were only 280% of ZTC at 5 hr and returned to ZTC value by 12 hr. Plasma progesterone levels in the aborting cows remained unaffected until 12 hr followed by a progressive decline through 18 hr to extremely low levels at 3, 4, and 5 days. Endotoxin-infusion caused hyperglycemia in both aborting and non-aborting cows and lactic acidemia in the aborting cows. Treatment with two doses of flunixin meglumine (FM, 1.1 mg/kg), an inhibitor of cyclooxygenase, 1 hr prior to endotoxin infusion and then 13 hr later, completely prevented the endotoxin-induced abortion and increases in the plasma PGF2 alpha, TxB2 and 6-keto-PGF1 alpha concentrations. The PGE level remained unaffected. Although FM treatment failed to abolish endotoxin-induced increases in the plasma cortisol and lactic acid levels, it effectively prevented marked decreases in the progesterone and increases in the glucose concentrations. It was concluded that the use of FM offers therapeutic promise in preventing bovine abortion caused by endotoxin resulting from bacterial infection during the 1st trimester of gestation.

Frequency of church attendance and blood pressure elevation.

Blood pressure levels were examined with regard to church attendance patterns in a group of white male heads of households who appeared in the 1967-1969 follow-up examination of the Evans County Cardiovascular Epidemiologic Study. A consistent pattern of lower systolic and diastolic blood pressures among frequent church attenders was found compared to that of infrequent attenders which was not due to the effects of age, obesity, cigarette smoking, or socioeconomic status.

Effect of the severity of maternal zinc deficiency on pregnancy outcome and infant zinc status in rhesus monkeys.

To investigate the effects of the severity of maternal zinc deficiency on early development, rhesus monkeys were fed diets that were either moderately zinc-deficient (MZD) (2 micrograms Zn/g) or marginal in zinc (M) (4 micrograms Zn/g) throughout pregnancy and lactation. Dams in the MZD group developed overt signs of zinc deficiency. Compared with control dams fed diets adequate in zinc (C) (50 or 100 micrograms Zn/g), both M and MZD dams showed low mitogen response. Pregnancy outcome was similar in all groups, and infants were considered healthy at delivery. From birth until d 30, infants were closely monitored for signs of zinc deficiency. On d 30, infants were killed and tissues were analyzed for several parameters reported to be affected by zinc status. MZD infants tended to have lower plasma zinc concentrations than C infants, although the difference was only significant at d 14. M infants tended to have lower plasma zinc concentrations than C infants. Mitogen response was lower in MZD and M infants than in C infants. However, mitogen responses were similar in MZD and M infants. Liver zinc concentrations were similar among the three groups of infants; however, zinc and metallothionein concentrations in (10,000 x g) liver supernatant fractions were lower in the MZD and M groups than in the C group. 65Zn absorption/retention was higher in MZD and M mothers and infants than in C mothers and infants; there were no marked differences between MZD and M mothers or infants. In contrast to whole-body absorption, 65Zn uptake/retention by isolated hepatocytes was similar among the three infant groups.(ABSTRACT TRUNCATED AT 250 WORDS)