Nutritional Wasting Disorders in Sheep

The different ovine production and breeding systems share the cornerstone of keeping a good body condition to ensure adequate productivity. Several infectious and parasitic disorders have detrimental effects on weight gains and may lead to emaciation. Flock health management procedures are aimed to prevent such conditions. Nutritional management is equally important to guarantee adequate body condition. Persistent bouts of low ruminal pH due to excess concentrate in the diet may lead to subacute ruminal acidosis. Pre-stomach motility disorders may also lead to ill-thrift and emaciation. An adequate mineral supplementation is key to prevent the effects of copper, selenium, and other micronutrients deprivation, which may include, among others, loss of condition. This review elaborates on the clinico-pathologic, diagnostic, and therapeutic aspects of some of these conditions, and highlights the necessity of considering them as contributors to states of wasting in sheep flocks.

Nano zinc supplementation in goat (Capra hircus) ration improves immunity, serum zinc profile and IGF-1 hormones without affecting thyroid hormones

The trial was aimed at evaluating probable superiority, if any of nano zinc (NZn) over inorganic zinc (Zn) on immunity, serum minerals and T₃ , T₄ , and IGF-1 hormone profiles in goats. NZn was synthesized by using 0.45 M aqueous solution of Zn nitrate and 0.9 M aqueous solution of sodium hydroxide (average particle size 74 nm). Twenty-four male goats were grouped into four groups as per their body weight and were supplemented with either a basal diet with concentrate and straw at 50:50 ratio (Negative control, NC) alone or supplemented with 50 mg/kg Zn (Control) from inorganic Zn source, that is ZnO (IZn-50), 50 mg/kg Zn from NZn (NZn-50) or 25 mg/kg Zn from NZn (NZn-25). No change was observed in thyroid hormone status on zero and 90th day of experimental feeding, but NZn supplementation improved (p < 0.05) IGF-1 level on 90th day serum samples. Zn supplementation improved the humoral immunity in all the groups irrespective of the source. Similarly, cell-mediated immunity (CMI) measured by skinfold thickness after injecting Con-A, was also improved in Zn supplemented groups than control at 6, 12 and 48 h of incubation. NZn-50 animals showed highest HI (haemagglutination inhibition) titre as well as skin thickness. The CD 4 + (cluster of differentiation in %) was more (p < 0.05) in Zn supplemented groups. NZn-50 showed higher (p < 0.05) CD 8 + count than NC and similar (p > 0.05) to IZn-50 and NZn-25 groups without affecting (p > 0.05) the ratio of CD 4 + , CD 8 + among the treatment groups. Thus, NZn supplementation at 25 mg/kg had similar immunity and serum T₃ , T₄ and IGF-1 profiles compared with IZn at 50 mg/kg dose.

Copper and Zinc Nutritional Issues for Agricultural Animal Production

Livestock have presented unique requirements and toxicity issues depending on the species for the various concentrations of Cu and Zn and their interactions with other nutrients especially Fe, Se, Mo, and S. Soil concentrations of these elements and their availability to crops influence the health of the crop and the amount found in vegetative tissues and seeds. Hence, many livestock issues are a result of the soils in the area where production is occurring (Loneragan et al. 1981). While water can provide minerals to animals, the amount consumed and availability are highly variable. Many discoveries about Cu were a result of low Cu concentrations and its availability due to interactions with other nutrients in the soils. Anemia, bone disorders, cardiovascular abnormalities, defective wool and hair, and infertility are signs/symptoms of Cu deficiency. Toxicity due to excess Cu is more likely to occur in sheep than other farm species. Swine are tolerant of high concentrations of dietary Cu, and it is often used as a growth stimulant in production. There are many species and physiological stages where the animal's Cu requirement is not known. Grazing animals can exhibit Zn deficiency when soils and forages contain limited concentrations of Zn. Pastures have been observed to be Zn-deficient in many parts of the world. However, non-ruminant animals usually receive adequate Zn when fed corn and soybean meal diets if there is not excessive Ca and Fe in their diets, but this is not true for rapidly growing young animals. Characteristics of a Zn deficiency include loss of appetite, reduced growth and reproduction, and impaired health of bone and skin tissues.

BILL E. KUNKLE INTERDISCIPLINARY BEEF SYMPOSIUM: Impact of mineral and vitamin status on beef cattle immune function and health

The importance of optimal mineral and vitamin nutrition on improving immune function and health has been recognized in the preceding decades. In the southeast, beef cattle are raised predominantly on forages that may be limiting in nutrients for optimal health, especially trace minerals such as Cu, Zn, and Se. Clinical deficiencies of these nutrients produce classic symptoms that are common to several nutrient deficiencies (e.g., slow growth and unthrifty appearance); however, subclinical deficiencies are more widespread and more difficult to detect, yet may result in broader economic losses. Dietary mineral concentrations often considered adequate for maximum growth, reproductive performance, or optimal immune function have been found to be insufficient at times of physiological stress (weaning, transport, comingling, etc.), when feed intake is reduced. The impacts of these deficiencies on beef cattle health are not apparent until calves have been subjected to these stressors. Health problems that are exacerbated by mineral or vitamin deficiencies include bovine respiratory disease, footrot, retained placenta, metritis, and mastitis. Many micronutrients have antioxidant properties through being components of enzymes and proteins that benefit animal health. In dairy cattle, high levels of supplemental Zn are generally associated with reduced somatic cell counts and improved foot health, possibly reflecting the importance of Zn in maintaining effective epithelial barriers. Neutrophils isolated from ruminants deficient in Cu or Se have reduced ability to kill ingested bacteria in vitro. Supplemental vitamin E, in its role as an intracellular antioxidant has been shown to decrease morbidity in stressed calves. There is more understanding of the important biological role that these nutrients play in the functioning of the complex and multifaceted immune system. However, there is still much to be learned about determining the micronutrient status of herds (and hence when supplementation will be beneficial), requirements for different genetic and environmental conditions, understanding the bioavailability of these nutrients from feedstuffs and forages, quantifying the bioavailability of different supplemental sources of these nutrients, and identifying the impact of dietary antagonists on these nutrients.

Nano zinc, an alternative to conventional zinc as animal feed supplement: A review

The uniqueness of Zn is that, it is the second most abundant trace element in the animal body but can't be stored in the body, thus regular dietary intake is required. Zinc oxide (ZnO) nanoparticles (NP) particles are being extensively used in paints, skin lotions pigments, food, electronics appliances, biological and pharmaceutical applications and many more. Zinc oxide nanoparticles are the specially prepared mineral salt having particle size of 1 to 100 nm. It promotes growth can act as antibacterial agent, modulates the immunity and reproduction of the animals. Both in lower and higher doses of specifications it has exhibited a variety of effects on animal performances. Apart from being highly bio-available, reports have already pointed out the growth promoting, antibacterial, immuno-modulatory and many more effects of nano zinc (nZn). These can be used at lower doses and can provide better result than the conventional Zn sources and indirectly prevents environmental contamination also. The toxicological studies provide mixed results in animal models. Studies been undertaken in diversified animal species and encouraging effects have been reported with nZn supplementation. However, there is a need to optimize the dose and duration of ZnO NP supplementation for human and livestock, depending on its biological effects. Actual bioavailability of ZnO NP in livestock is still to be worked out. In this review we have attempted to summarize, conclude the beneficial effects of nZnO and its possible usage as mineral supplement to different categories of human and livestock.

Effect of dose and source of supplemental zinc on immune response and oxidative enzymes in lambs

An experiment of 150 days was conducted on 42 male Nellore lambs (28.3 +/- 0.64 kg) to determine the effect of zinc (Zn) supplementation (0,15, 30 and 45 ppm) in diet from inorganic (ZnSO(4)) and organic (Zn proteinate) sources on immune response and antioxidant enzyme activities by allotting them randomly to 7 groups in completely randomized design. The basal diet (BD) contained 29.28 ppm Zn. The humoral immune response assessed at 75 d against B. abortus was higher (P<0.01) with 15 or 30 ppm Zn supplementation from organic source. The dose and source had no effect on titres against chicken RBC antigen. The cell mediated immune response assessed as delayed type hypersensitivity (DTH) response against phytohaemagglutinin-P and in vitro lymphocyte proliferative response against concanavalin A at 150 d was higher (P<0.05) at 15 ppm Zn supplementation compared to BD fed lambs. Supplementation of 45 ppm Zn had no positive effect on immune response. The DTH response and antibody titres against B.abortus were higher (P< 0.05) on Zn proteinate compared to ZnSO(4) at 15 ppm Zn supplementation. The lipid peroxidase activity was lower (P < 0.01), while the RBC superoxide dismutase and catalase activities were higher (P < 0.01) in lambs at 15 ppm Zn supplementation compared to BD diet fed lambs, assessed at 75 d of feeding. Serum globulin concentration and alkaline phosphatase (ALP) activity (75 d of experiment) was higher in Zn supplemented lambs. The ALP activity increased (P < 0.01) with increase in Zn supplementation and being higher when supplementation was from Zn proteinate compared to ZnSO(4). The study indicated that 15 ppm zinc supplementation was required for obtaining higher immune response in lambs when fed a basal diet containing 29.28 ppm Zn and supplementation as Zn proteinate had higher antioxidant enzyme activities and immune response compared to ZnSO(4).

How minerals may influence the development and expression of immunity to endoparasites in livestock

This review attempts to explain how dietary mineral intake may affect the immune system, with particular reference to gastrointestinal nematode infestations of livestock, and considers its significance for other gut infections as well as for other species. Of the 56 minerals found in mammalian tissues, 16 are currently considered to be essential, and a further 13 probably essential, for cell and tissue function. To date, eight of these have been shown to affect the function of the mammalian immune system directly. Nine others have roles in physiological pathways such as neurological or endocrine function, or protein or carbohydrate metabolism, which in turn regulate the immune system. The remainder may in the future be shown to have immunologically specific roles. The pathogenesis of mineral effects on immunity involves a number of pathways and molecular mechanisms. Major areas requiring further investigation are the relationship between deficiency of minerals and in vivo immune-mediated protection against disease, in particular diseases of the mucosa, and the mechanisms by which the minerals or their deficiency exert their effect on immunity. Research is also required into the possibility that animals in the process of acquiring gut immunity have higher requirements for minerals.

Role of antioxidants and trace elements in health and immunity of transition dairy cows

A number of antioxidants and trace minerals have important roles in immune function and may affect health in transition dairy cows. Vitamin E and beta-carotene are important cellular antioxidants. Selenium (Se) is involved in the antioxidant system via its role in the enzyme glutathione peroxidase. Inadequate dietary vitamin E or Se decreases neutrophil function during the perpariturient period. Supplementation of vitamin E and/or Se has reduced the incidence of mastitis and retained placenta, and reduced duration of clinical symptoms of mastitis in some experiments. Research has indicated that beta-carotene supplementation may enhance immunity and reduce the incidence of retained placenta and metritis in dairy cows. Marginal copper deficiency resulted in reduced neutrophil killing and decreased interferon production by mononuclear cells. Copper supplementation of a diet marginal in copper reduced the peak clinical response during experimental Escherichia coli mastitis. Limited research indicated that chromium supplementation during the transition period may increase immunity and reduce the incidence of retained placenta.

Micronutrients and immune function in cattle

Complex inter-relationships exist between certain micronutrients, immune function and disease resistance in cattle. Several micronutrients have been shown to influence immune responses. The relationship between deficiencies of some micronutrients and disease resistance is less clear. A number of studies have indicated that Cr supplementation may improve cell-mediated and humoral immune response as well as resistance to respiratory infections in stressed cattle. With respiratory-disease challenge models Cr generally does not affect disease resistance. Deficiencies of Cu, Se, vitamin E and Co in cattle reduce the ability of isolated neutrophils to kill yeast and/or bacteria. Cu deficiency reduces antibody production, but cell-mediated immunity is generally not altered. However, Cu deficiency appears to reduce production of interferon and tumour necrosis factor by mononuclear cells. Numerous studies have linked low vitamin E and/or Se status to increased susceptibility of dairy cows to intramammary infections. In contrast to findings in laboratory animals, marginal Zn deficiency does not appear to impair antibody production or lymphocyte responsiveness to mitogen stimulation in ruminants. Co deficiency has been associated with reduced resistance to parasitic infections. It is well documented that vitamin A-deficient animals are more susceptible to various types of infections. beta-Carotene, possibly via its antioxidant properties, may affect immune function and disease resistance independent of its role as a precursor of vitamin A.

Zinc oxide and amino acids as sources of dietary zinc for calves: effects on uptake and immunity

Calf starter diets were formulated to contain 60 ppm of Zn, 150 or 300 ppm of Zn in the form of Zn-Met and Zn-Lys, or 300 ppm of Zn in the form of ZnO to compare relative bioavailability and effects on immunity. Holstein heifer calves were weaned at wk 5 and fed experimental starter diets from wk 6 to 12. Feed intake, body weight, Zn concentrations in liver and serum fractions, and mineral concentrations in serum were measured to determine the effects of treatment. In addition, peripheral blood lymphocyte blastogenesis, interleukin-2 production, cytotoxic activity, and the ability of blood neutrophils to phagocytose and kill bacteria were assessed at wk 0, 2, 4, and 6 of the trial. Feed intakes and body weight gains were similar among calves. Concentrations of Zn in serum were elevated in calves fed 300 ppm of Zn as Zn-Met and Zn-Lys but not in calves fed ZnO. Concentrations of Zn in liver were significantly elevated by 300 ppm of Zn in the form of Zn-Met and Zn-Lys (360 micrograms/g) but not by the other Zn treatments or by the control (245 micrograms/g). No treatment had an effect on the concentrations of Lys and Met in serum; however, concentrations of Lys did decrease in serum as the age of the calves increased. There was no significant treatment effect on mitogen-induced lymphocyte blastogenesis, interleukin-2 production, lymphocyte cytotoxicity, or phagocytic and intracellular killing ability of blood neutrophils. These data indicated greater absorption and retention of Zn when administered in the form of Zn-Met and Zn-Lys than that when ZnO was administered to young calves. However, there was no advantage to the immune function of extra dietary Zn.