The The effect of ketones on estrogen, progesterone, ovulatory follicle size, estrus and fertility in Holstein Cows

2021 Turk veterinerlik ve hayvancilik dergisi  
3 This study aimed to investigate the effect of hyperketonemia on estrogen, progesterone 4 and ovarian follicle size during postpartum as well as on pregnancy rate at first insemination. 5 Regarding this, 90 Holstein cows were selected from one of the industrial dairy farms in 6 Isfahan province, Iran. Estrus synchronization was routinely applied to all cows using the 7 Ov Synch method. The blood sample of the cows was taken two times. The first blood 8 sample was taken in 7 -14 days after
more » ... ng; to measure Beta hydroxybutyrate (BHBA), 9 and the second sample was taken at the first insemination to measure the 17-β oestradiol and 10 progesterone hormones. The pregnancy status was recorded at the first insemination. T-test 11 analysis was used to evaluate the effects of hyperketonemia on the concentration of steroid 12 hormones and pregnancy rate at first insemination. 4.4% of cows (4 of 90) had subclinical 13 ketosis (SCK) (BHBA greater than 1000 μmol / L). Results showed that cows with BHBA 14 levels greater than 600 μmol / L in 7 -14 days of postpartum had lower 17-β oestradiol levels 15 (P = 0.04) and higher progesterone levels (P = 0.06) at the time of insemination. Pregnant 16 cows also had significantly lower serum BHBA and higher 17-β oestradiol levels than non-17 pregnant cows at first insemination. The levels of BHBA, estrogen, and progesterone were 18 not significantly different in cows with different ovulation follicle sizes (P > 0.05). However, 19 the level of BHBA was lower in cows that exhibit symptoms of estrus at the time of 20 insemination (P = 0.07). 17-β oestradiol levels were higher and progesterone levels were 21 lower in cows with estrus symptoms with P = 0.07 and P = 0.01, respectively. The present study confirms that higher ketone bodies have negative effects on 17-β oestradiol level and 23 fertility. Also it appears that postpartum return to estrus is associated with high 24 concentrations of 17-β oestradiol and a low concentration of BHBA in early lactation. 25 Keywords: Beta hydroxybutyrate (BHBA), Estrogen, Progesterone, Pregnancy at first 26 insemination, Follicular size, Estrous Symptoms 27 28 3 1. Introduction 29 The dairy cows are subjected to a period of negative energy balance (NEB), metabolic 30 stress, and body condition score (BCS) loss, due to the use of body reserves in response to 31 excessive energy requirement for milk production in postpartum [1, 2]. The feeding rate is 32 not sufficient to meet the requirements of milk production during this period. In addition, 33 the genetic selection to produce more milk and an inappropriate feeding diet can increase 34 the rate and duration of NEB [3, 4, 5]. In these circumstances, reduced blood glucose and 35 hormonal changes; especially increased glucagon levels, lead to metabolic disorders such as 36 glycogenolysis, lipolysis, beta-oxidation of fats, gluconeogenesis, and ketogenesis, and 37 ultimately lead to the replacement of lipids and increasing the production of Ketones (such 38 as acetic acid, acetone, and BHBA) in the liver [6]. 39 The increase in the level of ketones during early lactation is due to the body's metabolic 40 response to excess energy demand. However, the increased ketone levels in the blood are 41 associated with poor fertility, decreased milk production, and risk of abomasum replacement 42 [7]. Cattle with ketosis usually show symptoms of other diseases such as metritis, 43 endometritis, placenta retention, and mastitis [8, 9, 10, 11]. 44 It has been demonstrated that NEB affects subsequent fertility in early lactation by 45 impaired hypothalamic-pituitary-ovarian axis [12]. The duration and amount of NEB are 46 associated with high concentrations of growth hormone and low concentrations of insulin 47 and IGF, which directly decreases the follicle quality and its response to gonadotropins [12, 48 13]. In addition, NEB is associated with a decrease in the concentration of LH surge, which 49 in turn delays the onset of Corpus luteum activity, increases the prevalence of ovarian cyst, 50 4 and reduces the chance of pregnancy at first insemination [5, 14]. Laminitis, high somatic 51 cell count, low BCS, and increased milk production can have detrimental effects on the 52 fertility of dairy cows and reduce the GnRH release. As a result, it reduces LH pulses and 53 estradiol production and leads to impaired estrus behavior [15]. However, there are limited 54 reports about the effects of NEB on postpartum estrus. It is assumed that NEB decreases 55 estradiol concentration prior to ovulation which results in fewer estrus symptoms [13]. The 56 aim of this study was to evaluate the effect of hyperketonemia on the concentrations of 17-57 β oestradiol (estradiol) and progesterone, ovulatory follicle size, and the estrus symptoms at 58 insemination as well as pregnancy rate at first insemination. 59 60 2. Materials and Methods 61 2.1 The Study Sample 62 This study was conducted on 90 Holstein multiparous (2 -5) cows in one of the dairy 63 farms in Isfahan province. Cows were kept in the farmyard and fed based on TMR. The diet 64 consisted of alfalfa, corn silage, and the concentrates containing barley, maize, soybeans, 65 organic and mineral supplements, salts and micronutrients. Cows were milked by milking 66 machine three times daily, at 6 a.m., 2 p.m., and 10 p.m. The average herd milk yield was 67 33 kg per cow per day. 68 69 2. 2 Sampling 70 The blood samples were taken during postpartum two times: first, 7 -14 days of 71 postpartum to measure the BHBA, and second; at first insemination, to measure estradiol and 72 5 progesterone levels. 10 ml of blood was collected at each sampling time from the jugular 73 vein. Serums transferred to the laboratory immediately and were stored at -20 °C. The 74 samples were recollected if they were hemolyzed. 75 76 2.3 Measurement of parameters in blood 77 Serums were finally sent to the clinical pathology laboratory under cold temperatures. 78 The BHBA content measured by Autoanalyzer BT-3000 (Biotechnica, Biotecnica 79 Instruments, Italy) and Randox kit (Randox Laboratories Ltd, UK)). Also, estradiol content 80 by ELISA with the sensitivity of 8.2 pg/ml, C.V.%: 3.9 and intra-assay and inter-assay 81 coefficients of variations: 9 and 10 % (estradiol AccuBind, 4925-300, Monobind, USA), and 82 progesterone content by ELISA with the sensitivity of 0.105 ng/ml, C.V.%: 3.9 as well as 83 intra-assay and inter-assay coefficients of variations with 3.1 and 7 %, respectively 84 (progesterone AccuBind, 4825-300, MonoBind, USA) were measured. 85 86 2.4 Management of Fertility 87 The Ov Synch (Ovulation Synchronization) protocol was performed for all cows after the 88 clean test (32 to 35 days of postpartum) and confirmation of genital health. Ovulation 89 follicular size and incidence of estrus symptoms were recorded on the day of insemination. 90 Pregnancy diagnosed 32 to 35 days after insemination by Ultrasonography (easy-scan BCF 91 model) and was confirmed 45 days after insemination. The date of calving, the date of the 92 first insemination, the Subsequent possible insemination and pregnancy test results were 93 recorded. 102 p-value of less than 0.05 or 0.1 was considered significant. 103 104 3. Results 105 3.1 The mean concentrations of BHBA, estradiol and progesterone 106 The mean concentrations of BHBA, estradiol, and progesterone are presented in Table 1 . 107 108 3.2 The effect of hyperketonemia on the concentration of estrogen, progesterone and 109 follicular size 110 In this study, cows were divided into two groups based on BHBA levels to evaluate the 111 effect of hyperketonemia on estradiol and progesterone concentrations. BHBA levels of the 112 first group were greater than or equal to 600 μmol / L and BHBA levels of the second group 113 were less than 600 μmol / l. Table 2 shows the effect of hyperketonemia on estradiol estradiol 114 and progesterone concentrations. estradiol level in the first group was significantly lower than 157 determination of SCK for blood BHBA or performed blood sampling during the first week 158 after calving. In these cases, the prevalence of SCK was higher [7, 14, 19]. In our study, the 159 9 prevalence of SCK was 24.4% (22 of 90 cows) by considering 600 µmol BHBA threshold 160 levels. 161 A dairy cow can get SCK and recover within five days [14, 20]. In the present study, the 162 cows were tested only once which was between 7 and 14 days of postpartum. In a study by 163 McArt et al. [14], the SCK prevalence peak was reported within the five days of lactation 164 (DMI), whereas in our study, the sampling was performed after seven days of postpartum. 165 Nevertheless, our study was performed according to the methods in previous literature [21, 166 22]. 167 In ideal conditions, the sampling should perform several times during the first month of 168 lactation to reduce misclassification bias. Unfortunately, there were limitations regarding the 169 time and budget in our study. However, the present study followed the same sampling 170 protocol which also used in a large number of studies that examined SCK risk factors [5, 22, 171 23]. 172 173 The Relationship between Steroid Hormones and Hyperketonemia 174 The cows also were divided into two groups based on BHBA levels with equal to or 175 greater than 600 µmol / L (n = 22) and less than 600 µmol / L (n = 68). Cows with BHBA 176 greater than 600 µmol / L at 7 -14 days postpartum were found to have lower estradiol (P = 177 0.04) and higher progesterone (P = 0.06) at insemination. In general, cows with NEB 178 (Hyperketonemia), elevated BHBA, NEFA, and urea in their blood which causes changes in 179 the follicular environment, oocyte quality, and ultimately a defect in oocyte development. 180 On the other hand, the NEB affects the liver which decreases insulin-like growth factor that
doi:10.3906/vet-2005-123 fatcat:2h7lhrfh2zg53n5hvcprigshhm