Jahani-Moghadam M, Mahjoubi E, Dirandeh E
Department of Animal Science, Sari Agricultural Sciences and Natural Resources University, Sari, Iran.
Department of Animal Science, University of Zanjan, Zanjan, Iran.
J Dairy Sci. 2015 Mar;98(3):1828-35. doi: 10.3168/jds.2014-8789. Epub 2014 Dec 26.
This study was done to investigate the effect of feeding linseed on blood metabolites, incidence of cystic follicles, resumption of postpartum ovarian cyclicity, pregnancy rate, milk production, and composition in fresh Holstein dairy cows. A total of 399 dairy cows were assigned randomly to 2 diets. Diets contained either protected palm oil (CON) or extruded linseed (LIN) and were fed from calving to d 40 postpartum. Ovaries of each cow were examined on d 10, 20, 30, and 40 after parturition (parturition=d 0) by transrectal ultrasonography to determine follicular development, ovarian disorders, and cyclicity. Blood samples were collected at 14-d intervals for 6 wk starting on the day of parturition to determine plasma concentrations of glucose, β-hydroxybutyrate (BHBA), nonesterified fatty acids (NEFA), and blood urea N (BUN). Results showed plasma glucose concentration was affected by the diets and was greater in the LIN treatment, but BHBA, NEFA, and BUN concentrations were similar among treatments. Dietary treatments had no significant effect on milk production and composition except milk fat percentage that significantly decreased in cows fed LIN (3.55%) compared with those fed with CON (4.17%). Plasma progesterone concentrations were greater in LIN treatment than CON treatment (1.31±0.09 vs. 0.87±0.09) at early postpartum. The resumption of cyclicity and onset of estrus were influenced by treatments and reduced by 7 d in LIN treatment compared with CON treatment. Cows fed diets enriched in LIN fatty acids had a lesser incidence of cystic follicles. Treatments did not differ significantly in terms of the number of days open, number of services per pregnancy, and pregnancy rate. In conclusion, feeding linseed immediately after parturition decreased milk fat and incidence of cystic follicles, increased progesterone concentrations early postpartum, and caused earlier resumption of cyclicity but did not affect pregnancy rate.
本研究旨在调查给初产荷斯坦奶牛饲喂亚麻籽对其血液代谢物、卵泡囊肿发生率、产后卵巢周期性恢复、妊娠率、产奶量及乳汁成分的影响。总共399头奶牛被随机分配到两种日粮组。日粮分别含有保护棕榈油（CON）或挤压亚麻籽（LIN），从产犊至产后第40天饲喂。在产后第10、20、30和40天（产犊日为第0天），通过直肠超声检查每头奶牛的卵巢，以确定卵泡发育、卵巢疾病和周期性。从产犊日开始，每隔14天采集一次血样，持续6周，以测定血浆葡萄糖、β-羟基丁酸（BHBA）、非酯化脂肪酸（NEFA）和血尿素氮（BUN）的浓度。结果显示，日粮对血浆葡萄糖浓度有影响，LIN处理组的血浆葡萄糖浓度更高，但各处理组的BHBA、NEFA和BUN浓度相似。日粮处理对产奶量和乳汁成分无显著影响，但饲喂LIN的奶牛乳脂率（3.55%）显著低于饲喂CON的奶牛（4.17%）。产后早期，LIN处理组的血浆孕酮浓度高于CON处理组（1.31±0.09对0.87±0.09）。周期性恢复和发情开始受处理影响，与CON处理相比，LIN处理使其推迟了7天。饲喂富含LIN脂肪酸日粮的奶牛卵泡囊肿发生率较低。在空怀天数、每次妊娠配种次数和妊娠率方面，各处理组无显著差异。总之，产后立即饲喂亚麻籽可降低乳脂率和卵泡囊肿发生率，提高产后早期孕酮浓度，使周期性恢复提前，但不影响妊娠率。
