Abeni F, Bergoglio G, Masoero G, Terzano G M, Allegrini S
Section of Torino, Istituto Sperimentale per la Zootecnia, 1-10151 Torino, Italy.
J Anim Sci. 2004 Feb;82(2):438-44. doi: 10.2527/2004.822438x.
Relationships among plasma hormonal and metabolic variables in the last trimester of gestation in 59 Piedmontese dams (n = 15 heifers, n = 44 cows) and the calf birth weight (BWT) class of their offspring were investigated in seven herds. The BWT data were categorized as follows: > 50 kg (BWT-A), 46 to 50 kg (BWT-B), 41 to 45 kg (BWT-C), and < 41 kg (BWT-D). Blood samples were collected at 33, 36, and 39 wk of gestation. Packed cell volume (PCV) and plasma concentrations of insulin, estrone sulfate (E1SO4), NEFA, and creatinine were determined and correlated to BWT class. Creatinine: E1SO4 ratio also was calculated. Duration of gestation was greater for dams producing a BWT-A calf than for the other BWT classes, and calf BWT was heavier (P < 0.001) for calves in the BWT-A vs. BWT-D class. The heaviest calf in BWT-A was associated with the highest calving difficulty score. Insulin and PCV values were not affected by week of gestation, whereas plasma E1SO4, NEFA, and creatinine content increased (P < 0.001) and creatinine:E1SO4 decreased (P < 0.001) during late gestation. Calf BWT class did not affect PCV value. Plasma E1SO4 concentrations were lower (P < 0.01) in BWT-D dams than the other dams, showing the greatest difference at 39 wk of gestation. At 36 and 39 wk of gestation, dams bearing BWT-C and BWT-D calves had a higher (P < 0.01) plasma insulin concentration than those bearing BWT-A and BWT-B calves. Plasma NEFA concentrations at 39 wk of gestation were higher (P < 0.05) in dams of calf BWT-A than in the other dams. We conclude that plasma E1SO4 level is a variable that can be used to monitor problems related to a small size calf. Conversely, the forthcoming birth of a calf with a heavy BW seems to be preceded by a pronounced increase in plasma NEFA level in the dam just a few days before calving.
在七个牛群中，研究了59头皮埃蒙特母畜（15头小母牛，44头母牛）妊娠晚期血浆激素和代谢变量与它们后代的犊牛出生体重（BWT）类别之间的关系。BWT数据分类如下：>50千克（BWT-A）、46至50千克（BWT-B）、41至45千克（BWT-C）和<41千克（BWT-D）。在妊娠33、36和39周时采集血样。测定红细胞压积（PCV）以及胰岛素、硫酸雌酮（E1SO4）、非酯化脂肪酸（NEFA）和肌酐的血浆浓度，并将其与BWT类别相关联。还计算了肌酐：E1SO4比值。产下BWT-A犊牛的母畜的妊娠期比其他BWT类别的母畜长，且BWT-A类犊牛比BWT-D类犊牛重（P<0.001）。BWT-A中最重的犊牛与最高的产犊难度评分相关。胰岛素和PCV值不受妊娠周数的影响，而在妊娠后期血浆E1SO4、NEFA和肌酐含量增加（P<0.001），肌酐：E1SO4降低（P<0.001）。犊牛BWT类别不影响PCV值。BWT-D母畜的血浆E1SO4浓度低于其他母畜（P<0.01），在妊娠39周时差异最大。在妊娠36和39周时，产下BWT-C和BWT-D犊牛的母畜的血浆胰岛素浓度高于产下BWT-A和BWT-B犊牛的母畜（P<0.01）。在妊娠39周时，BWT-A犊牛的母畜的血浆NEFA浓度高于其他母畜（P<0.05）。我们得出结论，血浆E1SO4水平是一个可用于监测与犊牛体型小相关问题的变量。相反，即将产下体重较重的犊牛似乎在产犊前几天母畜血浆NEFA水平会显著升高。
