The objective of this study was to evaluate the association between uterine disease and indicators of neutrophil (PMN) and systemic energy status in dairy cows. Peripheral blood (120 mL) was collected weekly from 84 Holstein cows for PMN isolation and plasma collection from calving until 42 d in milk (DIM). The final analysis included 80 cows. Of those, 20 cows were classified as having metritis (fetid uterine discharge and fever), 15 as having subclinical endometritis (SCE; >or=10% PMN on uterine cytology), and 45 as healthy controls. Plasma haptoglobin concentration was increased only in cows that developed metritis. Neutrophil glycogen content was reduced in cows developing metritis compared with healthy cows on the day of calving and at 7 and 42 DIM. Cows with SCE had lower PMN glycogen content than healthy cows at 7, 28, and 42 DIM. Blood glucose was affected by disease status within parity. Primiparous metritis cows had greater blood glucose concentrations than healthy primiparous cows. Multiparous metritis cows tended to have lower blood glucose concentration than multiparous SCE cows. Cows that developed metritis and SCE had or tended to have greater NEFA and BHBA than healthy cows, mainly around calving. At calving, cows that developed metritis had higher plasma estradiol concentration than healthy cows and greater plasma cortisol than cows that had SCE. Plasma insulin was not affected. Plasma glucagon was increased for SCE cows. Cows that developed uterine disease experienced a greater degree of negative energy balance and had decreased lower intracellular PMN glycogen levels, which could be a major predisposing factor for disease because of decreased availability of oxidative fuels.
Lactating Holstein cows (n = 141) were synchronized to receive their first timed artificial insemination (TAI). Blood and milk samples were collected 25 and 32 d after TAI, and pregnancy status was determined 32 d after TAI using transrectal ultrasonography. Cows diagnosed pregnant with singletons (n = 48) continued the experiment in which blood and milk samples were collected and pregnancy status was assessed weekly using transrectal ultrasonography from 39 to 102 d after TAI. Plasma and milk samples were assayed for pregnancy-associated glycoprotein (PAG) levels using commercial ELISA kits. Compared to ultrasonography, accuracy was 92% for the plasma PAG ELISA test and 89% for the milk PAG ELISA test 32 d after TAI. Plasma and milk PAG levels for pregnant cows increased from 25 d to an early peak 32 d after TAI. Plasma and milk PAG levels then decreased from 32 d after TAI to a nadir from 53 to 60 d after TAI for the plasma PAG assay and from 46 to 67 d after TAI for the milk PAG assay followed by an increase from 74 to 102 d after TAI. Overall, plasma PAG levels were approximately 2-fold greater compared with milk PAG levels, and primiparous cows had greater PAG levels in plasma and milk compared with multiparous cows. The incidence of pregnancy loss from 32 to 102 d after TAI based on ultrasonography was 13% for cows diagnosed with singleton pregnancies, and plasma and milk PAG levels decreased to nonpregnant levels within 7 to 14 d after pregnancy loss. Both plasma and milk PAG levels were negatively correlated with milk production for both primiparous and multiparous cows. We conclude that stage of gestation, parity, pregnancy loss, and milk production were associated with plasma and milk PAG levels after TAI similarly. Based on plasma and milk PAG profiles, the optimal time to conduct a first pregnancy diagnosis is around 32 d after AI, coinciding with an early peak in PAG levels. Because of the occurrence of pregnancy loss, all pregnant cows should be retested 74 d after AI or later when plasma and milk PAG levels in pregnant cows have rebounded from their nadir.
An observational study was conducted on 1,498 cows in 3 large Italian dairy farms. The objective of the study was to evaluate the prognostic value of early lactation fat-to-protein ratio in milk. In all 3 herds, an intensive herd health monitoring program was being practiced that included weekly visits and extensive data collection on health, reproduction, production, and culling. A milk sample was collected from all cows at approximately 7 d postpartum and the ratio of fat-to-protein percentage in this milk sample was measured. Animals with a fat-to-protein ratio in early lactation greater than 2.0 showed an increase in postpartum diseases such as retained placenta, left-displaced abomasums, metritis and clinical endometritis. We also observed a decrease in early lactation milk production but this was limited to cows in lactation 2 and higher when the fat-to-protein ratio was greater than 2.0 in the early postpartum milk sample. Finally, an increased risk of being culled from the herd was observed, with the risk of culling increasing with increasing fat-to-protein ratio in the early lactation milk sample. No effect of fat-to-protein ratio was found on the incidence of clinical mastitis in the 3 herds. From this study, we conclude that analyses of milk components in early postpartum (6-9 days in milk), particularly the ratio of fat-to-protein percentage, is a valuable indicator of lipo-mobilization and the negative energy balance status in postpartum cows. Because a single milk sample is sufficient to provide valuable information, we suggest that this is a valuable addition to herd health programs on dairy farms.
1 March 2016 in Veterinary Clinics of North America: Food Animal Practice
Lactating Holstein cows (n=897) were randomly assigned to a 2×2 factorial arrangement of treatments to compare the main effects of presynchronization with GnRH 6 d before beginning an Ovsynch protocol (±GnRH) and a second PGF2α treatment 24h after the first (1 vs. 2 PGF2α) on pregnancies per artificial insemination (P/AI). This resulted in the following 4 treatments: (1) an Ovsynch protocol (GPG, control); (2) presynchronization with GnRH followed by an Ovsynch protocol (GGPG); (3) an Ovsynch protocol with a second PGF2α treatment (GPPG); and (4) presynchronization with GnRH followed by an Ovsynch protocol with a second PGF2α treatment (GGPPG). All cows were submitted for first timed artificial insemination (TAI) using a Presynch Ovsynch protocol, and cows detected in estrus after the second PGF2α treatment of the Presynch portion of the protocol were inseminated and removed from the experiment. Nonpregnant cows were resynchronized using an Ovsynch protocol initiated 32±3 d after artificial insemination. Blood samples were collected at the first GnRH treatment (G1), at the PGF2α treatment (PGF), and at the last GnRH treatment (G2) of the Ovsynch protocol and were assayed for progesterone (P4) concentrations. Overall, P/AI tended to be greater for cows receiving a second PGF2α treatment compared with cows not receiving the second PGF2α treatment (40 and 37% for GGPPG and GPPG treatments, respectively, vs. 33 and 32% for GGPG and GPG treatments, respectively). Interestingly, treatment effects on P/AI were detected only for resynchronized cows receiving second and greater TAI, but not for cows receiving first TAI. Fewer cows presynchronized with GnRH had low (<0.5ng/mL) P4 at G1 than cows not presynchronized (13 vs. 25%), and P4 was greater at PGF2α for cows presynchronized with GnRH (4.4 vs. 4.0ng/mL). Cows receiving 2 PGF2α treatments had lower P4 at G2 than cows receiving 1 PGF2α treatment (0.15 vs. 0.35ng/mL). Differences in P4 at PGF2α were detected only for resynchronized cows and not for cows submitted for first TAI. We conclude that presynchronization with GnRH 6 d before beginning an Ovsynch protocol tended to increase P4 at the first GnRH treatment of an Ovsynch protocol, and that a second PGF2α treatment 24h after the first decreased P4 at TAI, thereby increasing P/AI in cows resynchronized for second and greater TAI.
A composite pain scale for assessing and quantifying pain in rabbits (CANCRS) has been designed merging the Rabbit Grimace Scale (RbtGS) and a scale including clinical parameters (CPS). Construct validity and inter-rater reliability were assessed for CANCRS, for RbtGS and for CPS, in order to test their potential to detect pain in a clinical setting. Rabbits (n = 116) were either hybrids or purebreds and they were independently evaluated by two raters, who could be veterinarians (V) or veterinary medicine students (S). Score intervals determined four pain classes (No pain, Discomfort, Moderate pain and Severe pain) that matched presumptive pain classes associated with some pathological conditions. A chi-square test was used to assess the construct validity of the scales by checking how frequently scale results and presumptive pain classes matched. Sixty-nine patients were evaluated by one V and one S, whereas forty-seven rabbits were assessed by two V, in order to test inter-rater reliability. An intra-class correlation coefficient (ICC) was used to test reliability of the scales, whereas Cohen’s kappa tested inter-rater agreement for each parameter of the CANCRS. Construct validity results show that CANCRS and RbtGS efficiently reveal pain (P ≤ 0.05), while CPS does not (p > 0.05). Inter-rater reliability was very good for both CANCRS and CPS (ICC 0.88 V-V, 0.94 between V-S; ICC 0.97 V-V, 0.91 V-S) and good for RbtGS (ICC 0.77 V-V, 0.88 V-S); therefore, CPS reproducibility was better between veterinarians and students than between veterinarians. Inter-rater agreement between veterinarians and veterinary medicine students was moderate to very good for all the parameters included in the CANCRS (Cohen’s kappa >0,60). In conclusion, it is possible to state that the CANCRS has construct validity and it is a reliable tool for use in clinical practice, when coping with many rabbits with morphological differences. It is easy and fast to use and enriches the RbtGS with some clinical parameters that should be monitored during any clinical examination, allowing for capture of the multidimensional aspect of pain.