在乳牛分娩的前三週至後三週一般通稱為轉換期，這段期間乳牛除了須應付胎兒快速成長的營養需求，還需要應付產後泌乳造成的大量能量需求以及內分泌與環境變化造成的氧化壓力，再加上採食量於這期間往往會受到抑制而形成負能量平衡及免疫力下降等諸多問題。因此轉換期乳牛常發生酮症、皺胃異位、胎衣滯留、感染性疾病 (乳房炎及子宮炎等)以及繁殖表現下降等，故如何預防乳牛在轉換期健康狀況受到劇烈影響已經成為一個重要的課題。
　　本試驗總共分成兩個階段，旨在探討自行設計之綜合型添加物於轉換期給予乳牛額外補充，以發揮對於酮症、乳房炎及其他負面影響之預防潛力。第一階段的試驗以胎次將實驗牛群分成初產牛及經產牛，再以是否餵食添加物分成對照組及實驗組。綜合型添加物主要以丙二醇及甘油製成之粉末與維生素A、D、E及硒混合而成，實驗組的牛隻於分娩前三週開始每日餵食定量混合添加物至分娩後三週停止；而對照組則不改變原有飼養方式且不餵食添加物。檢測項目包含分娩當日及分娩後第1、2及3週之血糖、血液游離脂肪酸 (NEFA) 及β-羥基丁酸，還有試驗終止當日之乳產量及乳成份，此外還記錄分娩後至第一次做人工授精的間期及其他疾病資料。由於第一階段的試驗發現在初產牛有較顯著的試驗效益，故第二階段的試驗只鎖定初產牛，並以體態評分 3.5將牛隻分成胖的牛群及瘦的牛群，再分別細分為實驗組及對照組。試驗進行及採樣項目與方式比照第一階段，但在分娩前三週多加一次血樣採集作為試驗起始資料，且於試驗起初及試驗終止時各測定一次體態評分，以此來探討設計之添加物對不同體態的牛隻造成效益異同。
　　試驗發現初產牛在轉換期發生的負能量平衡情形會較經產牛嚴重，可能是因為初產牛除了須應付轉換期壓力之外還須額外應付自身成長所需能量，且在牛隻未分群的情況下，體型小之初產牛容易受到體型大之經產牛欺負而影響採食。在綜合型添加物額外補充下可從血液生化值發現負能量平衡的情形改善、乳產量增加、乳蛋白及非乳脂固形物上升及分娩後至第一次人工授精間期縮短的現象，雖改善項目未達顯著差異，但卻有一致改善的現象且改善效益在初產牛較為明顯。第二階段的試驗發現血液生化值的資料在瘦的牛群組別中，顯示負能量平衡較胖的牛群嚴重而與文獻相牴觸，很可能是因為分娩後牛隻未分群造成的競爭行為，導致肢體損傷及採食意願低落造成的。從血液生化值、乳成份及體組成流失上發現綜合型添加物對牛隻健康狀況的改善於胖的牛隻上較為明顯，但胖的牛隻因為在轉換期流失較多體態評分故在繁殖表現上改善效益並不明顯。本試驗合作之乳牛場在原本的飼料中已經有額外添加了足量的維生素A、D、E及硒，故在試驗中看不到本試驗設計之綜合型添加物對乳房炎產生預防的效果。
　　綜合試驗發現，轉換期乳牛於分娩後的分群十分重要，可以避免不必要的競爭行為，此外還需要嚴加控制乳牛分娩前的體態評分以避免繁殖表現下降。於轉換期額外補充此綜合型添加物可以改善負能量平衡並降低酮症發生的風險、提升乳產量、改善乳品質及改善繁殖表現。

Period from 3 weeks before to 3 weeks after parturition is usually called transition period. In this period, dairy cows will inevitably face lots of health problems like ketosis, mastitis, retained placenta, displaced abomasum and so on. The reasons are negative energy balance and decreasing concentrations of many trace elements due to decreasing dry matter intake and increasing energy demand caused by growing fetus and lactation. Therefore, how to help dairy cows get through transition period safely has become an important issue.
　　The objective of this experiment was to investigate the effects of supplementing transition dairy cows with experimental additives to prevent ketosis and mastitis. Experiment was divided into 2 parts. Treatment group was daily supplemented with additives consisted of Vit. A, D, E, Se and powder made from glycerol and propylene glycol from 3 weeks before to 3 weeks after calving. Blood samples were collected on the day right after calving and 1, 2 and 3 week after calving. Milk samples were collected on the day of 3 week after calving. Besides, daily milk yield, days from calving to first AI and health information were recorded. Experiment I was aimed at the difference between primiparity and multiparity, and experiment II was aimed at primiparity with different body condition score (BCS) due to supplementation effects on primiparity were more obvious in experiment I.
　　Results showed that primiparity faced more severe negative energy balance than multiparity did. There were improvements in negative energy balance, milk yield, milk components and reproductive performance when cows are supplemented with experimental additives. Although there was no statistically significant difference, but the effects were more obvious and consistent in primiparity. Results of experiment II showed that cows with lower BCS faced more severe negative energy balance than cows with higher BCS according to blood parameters. This finding is different from literatures, and the reason may be related to the feeding competition among cows with different body sizes. Although there was no significant difference, but there were improvements in negative energy balance, milk components and loss of BCS in cows with higher BCS. As to reproductive performance, improvement in cows with lower BCS was more obvious than cows with higher BCS. There was no obvious effect of preventing mastitis in experiment I and II due to high dose of trace elements in original daily rations of dairy farms.
　　 In conclusion, grouping in farms during transition period is important to prevent inevitable feeding competition among cows, and it will be easier to provide proper management to different groups of cows. In addition to this, supplementation with experimental additives can help alleviating negative energy balance and improving milk yield, milk composition and reproductive performance.

謝誌 １
摘要 II
ABSTRACT IV
目錄 i
圖目錄 iv
表目錄 vi
壹、前言 1
貳、文獻探討 2
一、轉換期乳牛面臨的風險 2
（一）體態評分的管控 2
（二）負能量平衡 5
（三）乳熱病及亞臨床低血鈣症 10
（四）瘤胃的健康狀況 13
（五）體內微量元素及抗氧化物 15
二、負能量平衡、酮症及其預防方式 19
(一) 亞臨床酮症檢驗標準 20
(二) 酮症發生機率 20
(三) 酮症對血液生化值的影響 21
(四) 酮症對繁殖表現的影響 21
(五) 酮症對牛隻其他健康狀況的影響 22
(六) 負能量平衡及酮症的預防方式 23
三、免疫能力下降及其預防方式 27
(一) 於轉換期額外補充維生素及硒 28
(二) 維生素E及硒應用上的交互關係 29
參、材料與方法 31
一、試驗動物 31
二、動物舍配置 32
三、餵飼方式 32
四、試驗處理 33
(一) 添加物餵食 33
(二) 血樣採集 35
(三) 乳樣採集 35
五、資料收集 36
(一) 血樣分析 36
(二) 乳樣分析 37
(三) 乳量及健康資料 37
(四) 體態評分 38
六、統計分析 38
肆、結果與討論 40
一、試驗Ｉ 40
（一）血液生化值 40
（二）乳量及乳成份 50
（三）繁殖表現 57
（四）健康資料追蹤 60
二、試驗II 62
（一）血液生化值 62
（二）乳量及乳成份 71
（三）體態評分 76
（四）繁殖表現 78
（五）健康資料追蹤 81
伍、結論 85
陸、參考文獻 86
柒、小傳 98

Adams, E. W. and C. G. Rickard. 1963. The antistreptococcic activity of bovine teat canal keratin. Am. J. Vet. Res. 24:122-135.
Batra, T. R., M. Hidiroglou, and M. W. Smith. 1992. Effect of Vitamin-E on Incidence of Mastitis in Dairy-Cattle. Can. J. Anim. Sci.72(2):287-297.
Bauman, D. E. and W. B. Currie. 1980. Partitioning of nutrients during pregnancy and lactation: a review of mechanisms involving homeostasis and homeorhesis. J. Dairy Sci.63(9):1514-1529.
Beam, S. W. and W. R. Butler. 1997. Energy balance and ovarian follicle development prior to the first ovulation postpartum in dairy cows receiving three levels of dietary fat. Biology of Reproduction 56(1):133-142.
Beam, S. W. and W. R. Butler. 1999. Effects of energy balance on follicular development and first ovulation in postpartum dairy cows. J. Reprod. Fertil. 54:411-424.
Bell, A. W. 1995. Regulation of organic nutrient metabolism during transition from late pregnancy to early lactation. J. Anim. Sci. 73(9):2804-2819.
Berge, A. C. and G. Vertenten. 2014. A field study to determine the prevalence, dairy herd management systems, and fresh cow clinical conditions associated with ketosis in western European dairy herds. J. Dairy Sci. 97(4):2145-2154.
Bertics, S. J., R. R. Grummer, C. Cadorniga-Valino, and E. E. Stoddard. 1992. Effect of prepartum dry matter intake on liver triglyceride concentration and early lactation. J. Dairy Sci. 75(7):1914-1922.
Block, E. 1984. Manipulating dietary anions and cations for prepartum dairy cows to reduce incidence of milk fever. J. Dairy Sci. 67(12):2939-2948.
Blomhoff, R. and H. K. Blomhoff. 2006. Overview of retinoid metabolism and function. J. Neurobiol. 66(7):606-630.
Blosser, T. H. 1979. Economic losses from and the national research program on mastitis in the United States. J. Dairy Sci. 62(1):119-127.
Bobe, G., J. W. Young, and D. C. Beitz. 2004. Invited review: pathology, etiology, prevention, and treatment of fatty liver in dairy cows. J. Dairy Sci. 87(10):3105-3124.
Butler, W. R. 1998. Review: effect of protein nutrition on ovarian and uterine physiology in dairy cattle. J. Dairy Sci. 81(9):2533-2539.
Butler, W. R. 2003. Energy balance relationships with follicular development, ovulation and fertility in postpartum dairy cows. Livest Prod. Sci. 83(2-3):211-218.
Butler, W. R. and R. D. Smith. 1989. Interrelationships between energy balance and postpartum reproductive function in dairy cattle. J. Dairy Sci. 72(3):767-783.
Cai, T. Q., P. G. Weston, L. A. Lund, B. Brodie, D. J. McKenna, and W. C. Wagner. 1994. Association between neutrophil functions and periparturient disorders in cows. Am. J. Vet Res. 55(7):934-943.
Cavestany, D., J. E. Blanc, M. Kulcsar, G. Uriarte, P. Chilibroste, A. Meikle, H. Febel, A. Ferraris, and E. Krall. 2005. Studies of the transition cow under a pasture-based milk production system: metabolic profiles. J. Vet. Med. A Physiol. Pathol. Clin. Med. 52(1):1-7.
Chan, A. C., K. Tran, D. D. Pyke, and W. S. Powell. 1989. Effects of dietary vitamin E on the biosynthesis of 5-lipoxygenase products by rat polymorphonuclear leukocytes (PMNL). Biochim. Biophys. Acta 1005(3):265-269.
Christensen, J. O., R. R. Grummer, F. E. Rasmussen, and S. J. Bertics. 1997. Effect of method of delivery of propylene glycol on plasma metabolites of feed-restricted cattle. J. Dairy Sci. 80(3):563-568.
Chung, Y. H., D. E. Rico, C. M. Martinez, T. W. Cassidy, V. Noirot, A. Ames, and G. A. Varga. 2007. Effects of feeding dry glycerin to early postpartum Holstein dairy cows on lactational performance and metabolic profiles. J. Dairy Sci. 90(12):5682-5691.
Cozzi, G., P. Berzaghi, F. Gottardo, G. Gabai, and I. Andrighetto. 1996. Effects of feeding propylene glycol to mid-lactating dairy cows. Anim. Feed Sci. Tech. 64(1):43-51.
Craven, N. and M. R. Williams. 1985. Defences of the bovine mammary gland against infection and prospects for their enhancement. Vet. Immunol. Immunopathol. 10(1):71-127.
DeFrain, J. M., A. R. Hippen, K. F. Kalscheur, and P. W. Jardon. 2004. Feeding glycerol to transition dairy cows: effects on blood metabolites and lactation performance. J. Dairy Sci. 87(12):4195-4206.
Donovan, G. A., C. A. Risco, G. M. D. Temple, T. Q. Tran, and H. H. van Horn. 2004. Influence of transition diets on occurrence of subclinical laminitis in Holstein dairy cows. J. Dairy Sci. 87(1):73-84.
Duffield, T. 2000. Subclinical ketosis in lactating dairy cattle. Vet. Clin. North Am. Food Anim. Pract. 16(2):231-253.
Duffield, T. F., K. D. LisSEore, B. W. McBride, and K. E. Leslie. 2009. Impact of hyperketonemia in early lactation dairy cows on health and production. J. Dairy Sci. 92(2):571-580.
Edmonson, A. J., I. J. Lean, L. D. Weaver, T. Farver, and G. Webster. 1989. A Body Condition Scoring Chart for Holstein Dairy-Cows. J. Dairy Sci. 72(1):68-78.
Emery, R. S., R. E. Brown, and A. L. Black. 1967. Metabolism of DL-1,2-propanediol-2-14C in a lactating cow. J. Nutr. 92(3):348-356.
Erskine, R. J., P. C. Bartlett, T. Herdt, and P. Gaston. 1997. Effects of parenteral administration of vitamin E on health of periparturient dairy cows. J. Am. Vet. Med. Assoc. 211(4):466-469.
Erskine, R. J., R. J. Eberhart, P. J. Grasso, and R. W. Scholz. 1989. Induction of Escherichia coli mastitis in cows fed selenium-deficient or selenium-supplemented diets. Am. J. Vet. Res. 50(12):2093-2100.
Erskine, R. J., R. J. Eberhart, L. J. Hutchinson, and R. W. Scholz. 1987. Blood selenium concentrations and glutathione peroxidase activities in dairy herds with high and low somatic cell counts. J. Am. Vet. Med. Assoc. 190(11):1417-1421.
Fisher, L. J., J. D. Erfle, G. A. Lodge, and F. D. Sauer. 1973. Effects of Propylene-Glycol or Glycerol Supplementation of Diet of Dairy-Cows on Feed Intake, Milk Yield and Composition, and Incidence of Ketosis. Can. J. Anim. Sci. 53(2):289-296.
Gillund, P., O. Reksen, Y. T. Grohn, and K. Karlberg. 2001. Body condition related to ketosis and reproductive performance in Norwegian dairy cows. J. Dairy Sci. 84(6):1390-1396.
Goff, J. P. 2008. The monitoring, prevention, and treatment of milk fever and subclinical hypocalcemia in dairy cows. Vet. J. 176(1):50-57.
Goff, J. P., K. Kimura, and R. L. Horst. 2002. Effect of mastectomy on milk fever, energy, and vitamins A, E, and beta-carotene status at parturition. J.Dairy Sci. 85(6):1427-1436.
Green, H. B., R. L. Horst, D. C. Beitz, and E. T. Littledike. 1981. Vitamin D metabolites in plasma of cows fed a prepartum low-calcium diet for prevention of parturient hypocalcemia. J. Dairy Sci. 64(2):217-226.
Grummer, R. R. 1995. Impact of changes in organic nutrient metabolism on feeding the transition dairy cow. J. Anim. Sci. 73(9):2820-2833.
Harrison, J. H. and H. R. Conrad. 1984. Effect of selenium intake on selenium utilization by the nonlactating dairy cow. J. Dairy Sci. 67(1):219-223.
Hayirli, A., R. R. Grummer, E. V. Nordheim, and P. M. Crump. 2002. Animal and dietary factors affecting feed intake during the prefresh transition period in Holsteins. J. Dairy Sci. 85(12):3430-3443.
Herdt, T. H. 2000. Ruminant adaptation to negative energy balance. Influences on the etiology of ketosis and fatty liver. Vet. Clin. North Am. Food Anim. Pract. 16(2):215-230.
Heuer, C., Y. H. Schukken, and P. Dobbelaar. 1999. Postpartum body condition score and results from the first test day milk as predictors of disease, fertility, yield, and culling in commercial dairy herds. J. Dairy Sci. 82(2):295-304.
Heuer, C., W. M. Van Straalen, Y. H. Schukken, A. Dirkzwager, and J. P. T. M. Noordhuizen. 2000. Prediction of energy balance in a high yielding dairy herd in early lactation: model development and precision. Livest Prod. Sci. 65(1-2):91-105.
Hoedemaker, M., D. Prange, H. Zerbe, J. Frank, A. Daxenberger, and H. H. Meyer. 2004. Peripartal propylene glycol supplementation and metabolism, animal health, fertility, and production in dairy cows. J. Dairy Sci. 87(7):2136-2145.
Hogan, J. S., W. P. Weiss, and K. L. Smith. 1993. Role of vitamin E and selenium in host defense against mastitis. J. Dairy Sci. 76(9):2795-2803.
Hogan, J. S., W. P. Weiss, D. A. Todhunter, K. L. Smith, and P. S. Schoenberger. 1992. Bovine neutrophil responses to parenteral vitamin E. J. Dairy Sci. 75(2):399-405.
Johnson, R. B. 1954. The treatment of ketosis with glycerol and propylene glycol. Cornell Vet. 44(1):6-21.
Jorritsma, R., H. Jorritsma, Y. H. Schukken, and G. H. Wentink. 2000. Relationships between fatty liver and fertility and some periparturient diseases in commercial Dutch dairy herds. Theriogenology 54(7):1065-1074.
Karami-Shabankareh, H., F. Kafilzadeh, V. Piri, and H. Mohammadi. 2013. Effects of feeding dry glycerol to primiparous Holstein dairy cows on follicular development, reproductive performance and metabolic parameters related to fertility during the early post-partum period. Reprod. Domest. Anim. 48(6):945-953.
Kehrli, M. E., Jr., B. J. Nonnecke, and J. A. Roth. 1989. Alterations in bovine neutrophil function during the periparturient period. Am. J. Vet. Res. 50(2):207-214.
Kim, I. H. and G. H. Suh. 2003. Effect of the amount of body condition loss from the dry to near calving periods on the subsequent body condition change, occurrence of postpartum diseases, metabolic parameters and reproductive performance in Holstein dairy cows. Theriogenology 60(8):1445-1456.
Kimura, K., T. A. Reinhardt, and J. P. Goff. 2006. Parturition and hypocalcemia blunts calcium signals in immune cells of dairy cattle. J. Dairy Sci. 89(7):2588-2595.
Kleen, J. L., G. A. Hooijer, J. Rehage, and J. P. Noordhuizen. 2003. Subacute ruminal acidosis (SARA): a review. J. Vet. Med. A Physiol. Pathol. Clin. Med. 50(8):406-414.
LeBlanc, S. 2010. Monitoring metabolic health of dairy cattle in the transition period. J. Reprod. Dev. 56 Suppl:S29-35.
LeBlanc, S. J., T. F. Duffield, K. E. Leslie, K. G. Bateman, J. TenHag, J. S. Walton, and W. H. Johnson. 2002. The effect of prepartum injection of vitamin E on health in transition dairy cows. J. Dairy Sci. 85(6):1416-1426.
LeBlanc, S. J., T. H. Herdt, W. M. Seymour, T. F. Duffield, and K. E. Leslie. 2004. Peripartum serum vitamin E, retinol, and beta-carotene in dairy cattle and their associations with disease. J. Dairy Sci. 87(3):609-619.
Loeffler, S. H., M. J. de Vries, Y. H. Schukken, A. C. de Zeeuw, A. A. Dijkhuizen, F. M. de Graaf, and A. Brand. 1999. Use of AI technician scores for body condition, uterine tone and uterine discharge in a model with disease and milk production parameters to predict pregnancy risk at first AI in Holstein dairy cows. Theriogenology 51(7):1267-1284.
Lomander, H., J. Frossling, K. L. Ingvartsen, H. Gustafsson, and C. Svensson. 2012a. Supplemental feeding with glycerol or propylene glycol of dairy cows in early lactation-effects on metabolic status, body condition, and milk yield. J. Dairy Sci. 95(5):2397-2408.
Lomander, H., H. Gustafsson, J. Frossling, K. Ingvartsen, T. Larsen, and C. Svensson. 2012b. Effect of supplemental feeding with glycerol or propylene glycol in early lactation on the fertility of Swedish dairy cows. Reprod. Domest. Anim. 47(6):988-994.
Macrae, A. I., D. A. Whitaker, E. Burrough, A. Dowell, and J. M. Kelly. 2006. Use of metabolic profiles for the assessment of dietary adequacy in UK dairy herds. Vet. Rec. 159(20):655-661.
Maus, R. W., F. A. Martz, R. L. Belyea, and M. F. Weiss. 1980. Relationship of dietary selenium to selenium in plasma and milk from dairy cows. J. Dairy Sci. 63(4):532-537.
Mayne, C. S., M. A. McCoy, S. D. Lennox, D. R. Mackey, M. Verner, D. C. Catney, W. J. McCaughey, A. R. Wylie, B. W. Kennedy, and F. J. Gordon. 2002. Fertility of dairy cows in Northern Ireland. Vet. Rec. 150(23):707-713.
McGuire, M. A., D. E. Bauman, D. A. Dwyer, and W. S. Cohick. 1995. Nutritional modulation of the somatotropin/insulin-like growth factor system: response to feed deprivation in lactating cows. J. Nutr. 125(3):493-502.
Meglia, G. E., A. Johannisson, L. Petersson, and K. P. Waller. 2001. Changes in some blood micronutrients, leukocytes and neutrophil expression of adhesion molecules in periparturient dairy cows. Acta Vet. Scand. 42(1):139-150.
Meikle, A., M. Kulcsar, Y. Chilliard, H. Febel, C. Delavaud, D. Cavestany, and P. Chilibroste. 2004. Effects of parity and body condition at parturition on endocrine and reproductive parameters of the cow. Reproduction 127(6):727-737.
Michal, J. J., L. R. Heirman, T. S. Wong, B. P. Chew, M. Frigg, and L. Volker. 1994. Modulatory effects of dietary beta-carotene on blood and mammary leukocyte function in periparturient dairy cows. J. Dairy Sci. 77(5):1408-1421.
Miller, J. K., E. Brzezinska-Slebodzinska, and F. C. Madsen. 1993. Oxidative stress, antioxidants, and animal function. J. Dairy Sci. 76(9):2812-2823.
Miyoshi, S., J. L. Pate, and D. L. Palmquist. 2001. Effects of propylene glycol drenching on energy balance, plasma glucose, plasma insulin, ovarian function and conception in dairy cows. Anim. Reprod. Sci. 68(1-2):29-43.
Mulligan, F. J., L. O''Grady, D. A. Rice, and M. L. Doherty. 2006. A herd health approach to dairy cow nutrition and production diseases of the transition cow. Anim. Reprod. Sci. 96(3-4):331-353.
Nickerson, S. 1992. Host resistance mechanisms to mastitis. Dairy research report-Louisiana Agricultural Experiment Station (USA).
Nielsen, N. I. and K. L. Ingvartsen. 2004. Propylene glycol for dairy cows - A review of the metabolism of propylene glycol and its effects on physiological parameters, feed intake, milk production and risk of ketosis. Anim. Feed Sci. Tech. 115(3-4):191-213.
Nonnecke, B. J. and K. L. Smith. 1984. Inhibition of mastitic bacteria by bovine milk apo-lactoferrin evaluated by in vitro microassay of bacterial growth. J. Dairy Sci. 67(3):606-613.
Nordlund, K. V., E. F. Garrett, and G. R. Oetzel. 1995. Herd-Based Rumenocentesis - a Clinical Approach to the Diagnosis of Subacute Rumen Acidosis. Comp. Cont. Educ. Pract. 17(8):S48-56.
NRC. 2001. Nutrient Requirements of Dairy Cattle. National Academies Press.
Oetzel, G. R. 2004. Monitoring and testing dairy herds for metabolic disease. Vet. Clin. North Am. Food Anim. Pract. 20(3):651-674.
Pickett, M. M., M. S. Piepenbrink, and T. R. Overton. 2003. Effects of propylene glycol or fat drench on plasma metabolites, liver composition, and production of dairy cows during the periparturient period. J. Dairy Sci. 86(6):2113-2121.
Putnam, M. E. and N. Comben. 1987. Vitamin E. Vet. Rec. 121(23):541-545.
Reinhardt, T. A., J. D. Lippolis, B. J. McCluskey, J. P. Goff, and R. L. Horst. 2011. Prevalence of subclinical hypocalcemia in dairy herds. Vet. J. 188(1):122-124.
Reist, M., A. Koller, A. Busato, U. Kupfer, and J. W. Blum. 2000. First ovulation and ketone body status in the early postpartum period of dairy cows. Theriogenology 54(5):685-701.
Remond, B., M. Cisse, A. Ollier, and Y. Chilliard. 1991. Slow release somatotropin in dairy heifers and cows fed two levels of energy concentrate. 1. Performance and body condition. J. Dairy Sci. 74(4):1370-1381.
Seifi, H. A., S. J. Leblanc, K. E. Leslie, and T. F. Duffield. 2011. Metabolic predictors of post-partum disease and culling risk in dairy cattle. Vet. J. 188(2):216-220.
Shin, E. K., J. K. Jeong, I. S. Choi, H. G. Kang, T. Y. Hur, Y. H. Jung, and I. H. Kim. 2015. Relationships among ketosis, serum metabolites, body condition, and reproductive outcomes in dairy cows. Theriogenology 84(2):252-260.
Shrestha, H. K., T. Nakao, T. Suzuki, M. Akita, and T. Higaki. 2005. Relationships between body condition score, body weight, and some nutritional parameters in plasma and resumption of ovarian cyclicity postpartum during pre-service period in high-producing dairy cows in a subtropical region in Japan. Theriogenology 64(4):855-866.
Simenew, K. and M. Wondu. 2013. Transition period and immunosuppression: critical period of dairy cattle reproduction. International Journal of Animal and Veterinary Advances 5(2):44-57.
Simpson, R. B., C. C. Chase, Jr., L. J. Spicer, R. K. Vernon, A. C. Hammond, and D. O. Rae. 1994. Effect of exogenous insulin on plasma and follicular insulin-like growth factor I, insulin-like growth factor binding protein activity, follicular oestradiol and progesterone, and follicular growth in superovulated Angus and Brahman cows. J. Reprod. Fertil. 102(2):483-492.
Smith, K. L., H. R. Conrad, B. A. Amiet, and D. A. Todhunter. 1985. Incidence of Environmental Mastitis as Influenced by Dietary Vitamin-E and Selenium. Kieler Milchw Forsch 37(4):482-486.
Smith, K. L., J. H. Harrison, D. D. Hancock, D. A. Todhunter, and H. R. Conrad. 1984. Effect of vitamin E and selenium supplementation on incidence of clinical mastitis and duration of clinical symptoms. J. Dairy Sci. 67(6):1293-1300.
Smith, K. L., J. S. Hogan, and W. P. Weiss. 1997. Dietary vitamin E and selenium affect mastitis and milk quality. J. Anim. Sci. 75(6):1659-1665.
Spicer, L. J., E. Alpizar, and S. E. Echternkamp. 1993. Effects of insulin, insulin-like growth factor I, and gonadotropins on bovine granulosa cell proliferation, progesterone production, estradiol production, and(or) insulin-like growth factor I production in vitro. J. Anim. Sci. 71(5):1232-1241.
Spicer, L. J. and S. E. Echternkamp. 1995. The ovarian insulin and insulin-like growth factor system with an emphasis on domestic animals. Domest. Anim. Endocrinol. 12(3):223-245.
Stephensen, C. B. 2001. Vitamin A, infection, and immune function. Annu. Rev. Nutr. 21:167-192.
Suriyasathaporn, W., C. Heuer, E. N. Noordhuizen-Stassen, and Y. H. Schukken. 2000. Hyperketonemia and the impairment of udder defense: a review. Vet. Res. 31(4):397-412.
Suthar, V. S., J. Canelas-Raposo, A. Deniz, and W. Heuwieser. 2013. Prevalence of subclinical ketosis and relationships with postpartum diseases in European dairy cows. J. Dairy Sci. 96(5):2925-2938.
Van Horn, H., C. J. Wilcox, and M. A. DeLorenzo. 1992. Large Dairy Herd Management. Amer. Dairy Science Assn.
Van Merris, V., E. Meyer, L. Duchateau, J. Blum, and C. Burvenich. 2004. All-trans retinoic acid is increased in the acute phase-related hyporetinemia during Escherichia coli mastitis. J. Dairy Sci. 87(4):980-987.
Walsh, R. B., J. S. Walton, D. F. Kelton, S. J. LeBlanc, K. E. Leslie, and T. F. Duffield. 2007. The effect of subclinical ketosis in early lactation on reproductive performance of postpartum dairy cows. J. Dairy Sci. 90(6):2788-2796.
Wathes, D. C., M. Fenwick, Z. Cheng, N. Bourne, S. Llewellyn, D. G. Morris, D. Kenny, J. Murphy, and R. Fitzpatrick. 2007. Influence of negative energy balance on cyclicity and fertility in the high producing dairy cow. Theriogenology 68 Suppl 1:S232-241.
Weiss, W. P., J. S. Hogan, K. L. Smith, and K. H. Hoblet. 1990. Relationships among selenium, vitamin E, and mammary gland health in commercial dairy herds. J. Dairy Sci. 73(2):381-390.
Weiss, W. P., J. S. Hogan, D. A. Todhunter, and K. L. Smith. 1997. Effect of vitamin E supplementation in diets with a low concentration of selenium on mammary gland health of dairy cows. J. Dairy Sci. 80(8):1728-1737.
Whitaker, D. A. 1997. Interpretation of metabolic profiles in dairy cows. Cattle Pract. 5 (1):57-60.