Determination of Blood Micromineral and Fat-Soluble Vitamin Values for White-tailed Deer

The current National Academies of Sciences, Engineering, and Medicine (NASEM) for trace mineral and vitamin requirements for cervids are based on data collected from various small ruminant species. Lack of baseline requirements make diet formulation for high fenced, white-tailed deer (Odocoileis virginianus) herds particularly ambiguous. This study was to determine a baseline value for whole blood and serum micromineral and vitamin concentrations for white-tailed deer in an attempt to establish dietary requirements of trace minerals and vitamins. Open does (n = 226) were sampled using jugular venipuncture during fall breeding procedures. Captive-raised does housed at various high fenced ranches (n = 3) throughout Texas were used, each with unique management strategies. Blood samples were analyzed for micromineral levels (Co, Cu, Fe, Mn, Mo, Se, and Zn) and fat-soluble metabolites (vitamin A, vitamin E, and cholesterol). Age of the doe and ranch were used as main effects using the GLM procedure in. Sampled averages across all ranches were 6.26 ng/mL of Co, 1.05 µg/mL of Cu, 219.47 µg/mL of Fe, 4.40 ng/mL of Mn, 4.23 ng/mL of Mo, 172.32 ng/mL of Se, 0.54 µg/mL of Zn, 286.76 ng/mL of vitamin A, 1.80 µg/mL of vitamin E, and 79.27 of cholesterol. Micronutrient levels were not affected by age; however, least squared differences existed between the main effect ranch for Co (P < 0.01), Cu (P < 0.01), Fe (P < 0.01), Mo (P < 0.01), Mn (P < 0.01), Se (P < 0.01), Zn (P < 0.01), vitamin E (P < 0.01), and cholesterol (P = 0.038) in serum. There was an observed interaction of age and ranch for vitamin A (P = 0.038). Factors such as feed, forage, soil, genetics, and health management protocols could explain the broad range in values. The establishment of circulating blood micronutrient levels will serve as a baseline for future white-tailed deer nutrient requirement research and feed formulation.

Energy metabolism of Yakutian horses in winter affected by feed additives for winter grazing

Научно-хозяйственный опыт по изучению эффективности использования кормовой добавки для воспроизводящего состава и жеребцов-производителей проведён в МИП «Меркурий» Амгинского улуса Республики Саха (Якутия) в феврале-марте 2019 года в местах тебенёвки во время подкормки. Рецептуры кормовых добавок для лошадей якутской породы разработаны на основе определения дефицита энергии, питательных и минеральных веществ в сене и тебенёвочном корме, проведены расчёты потребности кобыл и жеребцов-производителей в протеине, минеральных веществах и витаминах. При потреблении 11,07–12,8 кг сухого вещества сено-овсяного рациона жерёбые кобылы и жеребцы-производители испытывали дефицит практически во всех основных питательных веществах, за исключением сырой клетчатки, кальция и магния. Скармливание жерёбым кобылам и жеребцам-производителям кормовых добавок скорректировало минеральный, аминокислотный, витаминный обмен, положительно сказалось на биохимическом статусе крови, обмене веществ и энергии. Наибольшее поступление валовой энергии в организм отмечалось у кобыл и жеребцов-производителей опытных групп: они превосходили по данному показателю аналогов контрольных групп на 2,1% (173,85 ± 6,11 МДж) и 1,6% (179,82 ± 8,14 МДж) соответственно. В результате меньших потерь энергии с калом, мочой и метаном у жерёбых кобыл опытной группы достоверно выше оказалось её усвоение. Так, обменная энергия у жерёбых кобыл опытной группы была на 8,52% достоверно выше и составила 104,52 ± 1,08 МДж, у аналогов контрольной группы обменная энергия составила 96,31 ± 1,17 МДж (Р ≥ 0,95). У жеребцов-производителей опытной группы преимущество по величине изучаемого показателя над контролем составило 4,38% (107,68 ±9,44 МДж). Лучшее переваривание и использование энергии кормов способствовало повышению обменности валовой энергии у кобыл опытной группы на 3,55%, у жеребцов-производителей опытной группы — на 0,93% по сравнению с аналогами контрольных групп и составила у опытных кобыл 60,12%, у опытных жеребцов-производителей — 59,8%. The experiment was conducted at the MIP “Merkuriy”, the Republic of Sakha (Yakutia), in February-March of 2019. The investigation tested the effect of feed additives on Yakutian horses in the period of winter grazing. The compositions of feed additives were developed to supply animals with sufficient energy, nutrients and minerals lacking in hay and winter forage. Additionally, protein, mineral and vitamin requirements were analyzed. Horses fed with 11.07–12.8 kg of hay and oat dry matter suffered from deficiency in essential nutrients, except for crude fiber, Ca, and Mg. Feed additives optimized mineral, amino acid, and vitamin metabolisms as well as positively affected blood biochemistry, chemical reactions, and energy transformation. Horses obtained more gross energy via feed additives exceeding the control groups by 2.1 (173.85 ± 6.11 MJ) and 1.6% (179.82 ± 8.14 MJ). Pregnant mares had lower energy losses. They received 104.52 ± 1.08 MJ of exchange energy, significantly exceeding the control group by 8.52% (Р ≥ 0,95). Stallions exceeded the control group by 4.38% (107.68 ± 9.44 MJ) in the same parameter. Better forage digestibility and energy supply led to more effective transformation of gross energy into exchange energy: by 3.55% for mares (60.12%) and 0.93% — for stallions (59.8%).

58 Feed, feeding levels, and tissue analytics of vitamins: Observations from the field

Targeted vitamin inclusion rates within swine diets are typically at levels 2–7 times that of the known published requirements. These increased rates are mainly looked at as an “insurance policy” since very little vitamin research has been conducted in the last two decades and swine growth rates and reproductive traits have increased substantially during this same time. When production issues such as broken bones, downer animals, or sudden deaths occur, vitamin analysis is commonly done on feed, serum, or tissue samples. This discussion will shed light on observations around vitamin analytics that include variation due concentration within product, lab-to-lab variation, and within lab variation. In addition to discrepancies found in feed, serum and liver sample vitamin analytics do not seem to present a clear picture. Across multiple phases of production, these analysis consistently fall well below what would be considered to be reference values that are reported by diagnostic labs. This occurs not only in sick animals but also in animals that appear to be in perfect health and are consuming adequate levels of feed. In order to determine the impact of vitamin supplementation on performance and serum/tissue vitamin status, five trials across sows, nursery, and grow-finish swine were conducted. The goal of these trials is not to determine the various vitamin requirements, but to begin the conversation in order to help establish new reference values that are applicable to today’s genetics, vitamin supplementation levels, and rearing environments. Hopefully this presentation will lead to further questions and discussions within the industry regarding level of vitamin supplementation and the subsequent impacts on performance and serum/tissue vitamin status.