Parity Cows Research Articles

Genetic parameters for animal mortality in pasture-based, seasonal-calving dairy and beef herds

In the absence of informative health and welfare phenotypes, breeding for reduced animal mortality could improve overall health and welfare, provided genetic variability in animal mortality exists. The objective of the present study was to estimate genetic (and other) variance components for animal mortality in pasture-based, seasonal-calving dairy and beef herds across multiple life stages as well as to quantify the genetic relationship in mortality among life stages. National mortality records were available for all cattle born in the Republic of Ireland. Cattle were grouped into three life stages based on age (0 to 30 days, 31 to 365 days, 366 to 1095 days) whereas females with ≥1 calving event were also grouped into five life stages, based on parity number (1, 2, 3, 4, and 5), considering both the initial 60 days of lactation and a cow's entire lactation period, separately. The mean mortality prevalence ranged from 0.70 to 5.79% in young animals and from 0.53 to 3.86% in cows. Variance components and genetic correlations were estimated using linear mixed models using 21,637 to 100,993 records. Where heritability estimates were different from zero, direct heritability estimates for mortality in young animals (≤1095 days) ranged from 0.006 to 0.040, whereas the genetic standard deviation ranged from 0.015 to 0.034. The contribution of a maternal genetic effect to mortality in young animals was evident up to 30 days of age in dairy herds, but this was only the case in preliminary analysis of stillbirths in beef herds. Based on the estimated genetic standard deviation in the present study, the incidence of mortality in young animals could be reduced through breeding by up to 3.4 percentage units per generation. For cows, direct heritability estimates for mortality, where different from zero, ranged from 0.003 to 0.049. The genetic standard deviation for mortality in cows ranged from 0.005 to 0.016 during the initial 60 days of lactation and ranged from 0.011 to 0.032 during the cow's entire lactation. Genetic correlations among the age groups as well as between the age groups and cow parities had high standard errors. Genetic correlations among the cow parities were moderate to strongly positive (ranging from 0.66 to 0.99) and mostly different from zero. Results from the present study can be used to inform genetic evaluations for mortality in young animals and in cows as well as the potential genetic gain achievable.

Exploration of factors determining milk production by Holstein cows raised on a dairy farm in a temperate climate area.

In this study, we examined factors that affected milk production by cows raised in a temperate climate area. We conducted this study on a large dairy farm containing approximately 2000 Holstein cows, located in a temperate climate area. We collected 7803 calving records for 4069 cows from 2012 to 2016. We then assessed the effect of hot weather on milk yield by examining three climate factors: season, maximum temperature (MAX), and the temperature and humidity index (THI). We found that increases in heat stress caused linear decreases in milk yield (P < 0.05). Additionally, the effects of the three climate factors on milk yield varied depending on cow parity and days open (P < 0.05). Thus, management procedures should consider cow parity and lactating stage to minimize the negative effects of heat stress on milk production. We also found that the lowest Akaike information criterion value was obtained in our model when using THI for 305-day milk yield. This suggests that THI is a more accurate variable for evaluating heat stress than MAX or season.

Influence of Breed and Parity on Teat and Milking Characteristics in Dairy Cattle

Abstract The aim of this study was to determine some morphological traits of the udder teat and their influence on the milk flow rate in three dairy cattle breeds (Brown Swiss, Holstein and Simmental). The average milking time and milk yield was 8.79±0.16 minutes and 9.40±0.28 kg, respectively. There was a finding that the breed of the dairy cows had no effect on the total milking time, with the Holstein cows having the highest milk yield (P&lt;0.01). The average milk flow rate was 1.09±0.04 kg/minute and the Holstein cows had the highest milk flow rate (P&lt;0.05). The cow parity didn’t affect the milk flow rate and the milk yield. The average teat length, average teat diameter and average teat volume varied among the cattle breeds and were highest in the Brown Swiss, and lowest in the Simmental cows. In conclusion, the milk flow rate varies among cattle breeds, and it was observed that dairy cows with high milk yields have higher milk flow rates.

A randomized controlled trial on the effect of incomplete milking during the first 5 days in milk on reproductive performance of dairy cows

The main objective of the current study was to measure the effect of incomplete milking on luteal activity and on pregnancy hazard. We also aimed to study the effect of early-lactation hyperketonemia (i.e., β-hydroxybutyrate blood concentration ≥1.4 mmol/L during the first 3 wk in milk) on those reproductive outcomes. Multiparous Holstein cows (n = 853) from 13 commercial herds were enrolled in a randomized controlled trial. Cows were assigned to a control or a treatment group, incompletely milked (10-14 L of milk collected/d) from 1 to 5 DIM. Blood samples were collected once a week during weeks in milk 1 to 3 for β-hydroxybutyrate blood concentration, and a threshold of 1.4 mmol/L was used to define hyperketonemia. During weeks in milk 5 and 7, cows were sampled for progesterone blood concentration, and a threshold of 1 ng/mL was used to define luteal activity. Reproductive information and culling dates were obtained through herd records. Logistic regression models and survival analyses were used to assess the effect of treatment on luteal activity and on pregnancy hazard, respectively. Analogous models were used to investigate the effect of early-lactation hyperketonemia on reproductive outcomes. The odds of luteal activity for incompletely milked cows were 1.1 (95% confidence interval: 0.72-1.7) times those of conventionally milked cows. The effect of treatment on pregnancy hazard varied as a function of time, parity, and start of the breeding period. In second-parity cows that started the breeding period <55 d in milk, the pregnancy hazard (95% confidence interval) in incompletely milked cows was 576.3 (240.0-1,383.7), 36.9 (18.9-72.1), 6.8 (3.3-13.8), 2.5 (1.0-5.9), and 0.13 (0.07-0.26) times that of conventionally milked cows at 1 to 21, 22 to 43, 44 to 65, 66 to 87, and >87 d after the voluntary waiting period, respectively. The treatment did not have an effect on pregnancy hazard in cows in third parity or greater or in those starting the breeding period ≥55 d in milk. Early-lactation hyperketonemia was not associated with any of the reproductive outcomes. In conclusion, the incomplete milking protocol had no effect on luteal activity and had a positive effect on pregnancy hazard in second-parity cows in herds with a short voluntary waiting period (<55 d). We did not observe an effect of early-lactation hyperketonemia on luteal activity or on pregnancy hazard.

Risk factors limiting first service conception rate in dairy cows and their economic impact.

ObjectiveWe determined the risk factors limiting first service conception (FSC) rate in dairy cows and their economic impact.MethodsData were collected from 790 lactations regarding cow parity, peri- and postpartum disorders, body condition score (BCS), reproductive performance, and expenses associated with reproductive management (treatment, culling, and others). Initially, we identified the risk factors limiting FSC rate in dairy cows. Various biological and environmental factors, such as herd, cow parity, BCS at 1 month postpartum and first artificial insemination (AI), resumption of cyclicity within 1 month of calving, year, AI season, insemination at detected estrus or timed AI, peri- and postpartum disorders, and calving to first AI interval, were evaluated. Next, we evaluated the economic impact of the success or failure of FSC by comparing the expense associated with reproductive management until conception between cows that did or did not conceive at their first service.ResultsCows with BCS <3.0 had a lower probability of conceiving at first insemination (odds ratio [OR] = 0.64, p<0.05) than cows with BCS ≥3.0. Cows inseminated during summer were less likely to conceive (OR = 0.44, p<0.001) than cows inseminated during spring. Cows with peri- or postpartum disorders were less likely to conceive (OR = 0.55, p<0.001) than cows without disorders. Survival curves generated using MedCalc showed an 81 day extension in the mean interval between calving and conception in cows that failed to conceive over those that did conceive at first insemination. Cows failing conceive required additional expenditure on reproductive treatment ($55.40) and other management ($567.00) than cows that conceived at first insemination.ConclusionLower BCS, hot weather at first insemination, and peri- and postpartum disorders are risk factors limiting FSC, which result in an economic loss of $622.40 per dairy cow.

Field Investigation on Sub-clinical Mastitis in Cows in Different areas of Barisal district in Bangladesh

In every year, Subclinical mastitis (SCM) frequently occurs and results huge economic losses in livestock industry of Bangladesh. This study was redacted to estimate the present status of SCM in cow in selective area of Barisal district. For determining sub-clinical mastitis, a total of 152 milk samples of clinically suspected cows were subjected to White Side Test (WST) and Surf Field Mastitis Test (SFMT). Specifically, the milk samples of each individual cows which were positive to both WST and SFMT considered as SCM indicating 35.52% prevalence. Other than the local breed cows, the cross bred cows showed significantly higher prevalence, is 47.06%. In consideration to age variation, highest prevalence was observed at 5 to 7 years of age in both types where cross breed was 54.71% and 36.67% for local breed cows. Though highest prevalence was recorded as 34.78% in 2nd parity of local breed cows but the cross breed cows showed highest prevalence 54.55% in their 3rd parity. Afterward, non-pregnant cows showed the insignificantly higher prevalence (41.06%) than pregnant cows were 26.32%. Additionally, this study reported that the cross breed cows yielding more than 10 liters of milk (prevalence was 61.54%) were more prone to SCM than the others and also &gt;5 to 10 liters milk producing local breed cows (prevalence was 31.03%) were more susceptible to SCM than others. In a short, this study revealed that high milk yielding cross breed cows are more likely to SCM after their 3rd calving.

Association of milk flow curve and prevalence of mastitis pathogens in dairy cows

The objective of this work was to evaluate the association of bimodality of milk flow curves with microbiological status of mammary glands and parity of cows. We selected 167 primiparous and 148 multiparous Lithuanian Black and White dairy cows in 2nd to 4th month of lactation. The bimodality of milk flow was determined in 22.2% primiparous and in 38.6% multiparous cows (P less than 0.001). The most prevalent pathogens of mastitis were Staphylococcus aureus (15.3%), other staphylococci (22.2%) and streptococci (5.8%). Prevalence of mastitis pathogens in multiparous cows was 1.4 times and the bimodality of milk flow curves –1.7 times higher in comparison with primiparous cows (P less than 0.001). The bimodality of milk flow curve was mostly associated with the prevalence of Streptococcus agalactiae and Staphylococcus aureus (P less than 0.001). The increased frequency of mastitis pathogens (21.5%) in cows with the bimodal milk flow curves supports the negative effect of bimodality on udder health of cows (P less than 0.001).

Hock lesions in dairy cows in freestall herds: a cross-sectional study of prevalence and risk factors

BackgroundHock lesions (HL) in dairy cows are a common animal welfare problem in modern dairy production with freestall housing systems, but there are no large-scale studies addressing its epidemiology in Sweden. The aims of this cross-sectional study were to investigate the prevalence of HL of different severity in 100 Swedish freestall dairy herds, and to identify cow- and herd-related risk factors. Associations between HL and mastitis as well as culling were also investigated.ResultsIn total, 3217 cows from 99 herds were included in the statistical analyses. The overall cow prevalence of hair loss on the hock (mild HL) was 68% and the prevalence of ulceration or evident swelling of the hock, with or without hair loss, (severe HL) was 6%. The within-herd prevalence varied among herds, between 23 and 100% for mild HL, and between 0 and 32% for severe ones. Breed (higher risk for Swedish Holstein than for Swedish Red) and days in milk (higher risk at 181–305 days than at 0–90 days) were cow-related risk factors associated with both types of lesions, whereas higher parity and cleaner cows were associated only with increased risk of severe HL. A reduced risk for mild HL was seen in cows housed on mattresses compared to rubber mats, and in cows housed on peat compared to other bedding materials. Also, cows in herds with a high proportion of not yet inseminated heifers older than 17 months had a lower risk of mild HL than cows in herds with a low proportion. Risk for severe HL was lower when cubicles were of recommended width compared to under recommendation, for organic production compared to conventional, and when teat dip or no treatment after milking was used, compared to teat spray. For both mild and severe HL, herringbone milking parlors were associated with higher risk than tandem parlors. We found no significant associations between HL and mastitis or culling.ConclusionsThe prevalence of HL is high in Swedish dairy herds, although most lesions are mild. Several cow- and herd-related risk factors were identified and the results can be used to improve recommendations for the prevention of HL in Swedish freestall dairy herds.

Descriptive study for culling and mortality in five high-producing Spanish dairy cattle farms (2006\u20132016)

BackgroundHigh turnover rate in dairy farms due to culling and mortality is associated with poor animal welfare, an increase in production costs and lower economic benefits for the dairy farm. Understanding cow elimination better would help to formulate specific prevention measures and improve the efficiency of milk production in dairy farms. Culling and mortality data from five standard high-producing dairy farms in Spain were analysed over a period of 11 years (2006–2016). Data were collected by the same veterinary team and using the same software system.ResultsSignificant between-herd differences in eliminated cows were observed for type of elimination (slaughter or death on the farm), age at elimination, cause of elimination, number of lactations and production parameters, such as total days in milk, life milk yield, litres per day of productive life and litres per day of life. Culling and mortality were higher during the hot season and for cows of second and third parities. Between-herd differences were observed. Reproductive disorders (30.2%) were the most frequent reason for elimination, with low production (23.4%) being the second most frequent reason. Accidents on the farm (7.7%) were a more frequent cause of elimination than metabolic diseases (7.2%), locomotor disorders (2.4%) and obstetrics (2.4%).ConclusionsVeterinary teams or farmers’ associations can use culling and mortality information for benchmarking cow farms if data collection and analysis is standardised for comparability. The analysis of culling and mortality information should help farmers to improve efficiency.

Milk yield losses and cost of clinical mastitis in Friesian × Bunaji crossbred dairy cows in Zaria, Nigeria

Bovine mastitis is regarded as the most costly disease of dairy cows. Estimating its economic impact therefore gives farmers and veterinarians an insight into the costs of the disease at herd level and helps them make appropriate decisions regarding its control. The aim of this study was to determine the costs of clinical mastitis in Friesian × Bunaji crossbred dairy cows. Passive data collected between 2000 and 2015 was retrieved from the Dairy Research Programme of the National Animal Production Research Institute, Shika-Zaria, Nigeria and this was used to determine the input parameters for a simulation model. The parameters included the lactation and seasonal prevalence of clinical mastitis, average daily milk yield of cows, average illness period and the proportion of cows in each parity. Stochastic (Monte Carlo) simulation modelling of milk yield losses due to clinical mastitis was done using Microsoft® Excel with @Risk 7 add-in. The cost of a case of clinical mastitis at a base risk incidence of 35.2% was ₦5,005.85 ($15.87). The costs increased by 7.5% in a herd with 10% higher milk yield, while revenue generated was higher by 10.2%. The cost was 1.64% higher in a herd with fifty per cent of it cows in first parity than a herd with fifty per cent of its cows in third parity. 1.01% higher net revenue was generated from herds with fifty per cent of it cows in third parity than the herd with fifty per cent of its cows in first parity. Improving milk production potential of cows resulted in more cases of clinical mastitis, although the increase in revenue overshadows the added costs of clinical mastitis, successful control of mastitis will also significantly reduce production costs and improve the farm revenue.Keywords: Clinical mastitis, Cost, Cows, Friesian x Bunaji, Losses, Milk yield

Relationship between the parity and oxidative stress in high-performance Polish Holstein-Friesian cows after the peak of lactation

Relationship between the parity and oxidative stress in high-performance Polish Holstein-Friesian cows after the peak of lactation

Reproductive performance of Bos indicus beef cows treated with different doses of equine chorionic gonadotropin at the end of a progesterone-estrogen based protocol for fixed-time artificial insemination

Two experiments were performed to evaluate the reproductive performance of zebu beef cows treated with different doses of eCG at the end of a progesterone (P4)/estrogen based protocol for timed artificial insemination (TAI). In Experiment 1, suckling Bos indicus Nelore cows (n = 261) received, on day 0, a progesterone (P4) intravaginal device (PD) and an injection of 1 mg estradiol benzoate (EB). On day 8, the PD was removed, 500 μg of cloprostenol was injected, and cows were assigned to one of the following groups: Control (no treatment), 300 (300 IU of eCG), 600 (600 IU of eCG), and 900 (900 IU of eCG). On day 9, all cows received 1 mg EB and TAI performed 54–56 h after cloprostenol injection. A pregnancy diagnosis was done by ultrasound scanning 40 days after TAI, and the number of fetuses and calves was recorded at pregnancy diagnosis and at birth. More cows treated with eCG displayed estrus within 48 h after removal of the PD (42.3% vs. 11.6%, P < 0.01), and ovulated more than one follicle (42%, 58/138 vs. 1.8%, 1/54; P < 0.01). This effect on ovulation rate was dose dependent (P < 0.05). The pregnancy rate was affected only by cow parity (primiparous, 25.3% vs. multiparous, 48.9%; P < 0.01). Twin pregnancy was higher (P < 0.01) in cows treated with eCG (42%, 58/138) than controls (0%, 0/54). However, few cows (33.3%) were able to keep both fetuses intact until birth. For evaluation of ovarian characteristics by B-mode and Doppler ultrasonography, 43 Nelore cows were submitted In Experiment 2 to the same four groups described in Experiment 1. Although no difference (P > 0.1) was observed for size and blood perfusion in the pre-ovulatory follicles, corpus luteum was larger and with greater blood perfusion (P < 0.05) in eCG-treated cows. In conclusion, eCG increased the number of double/multiple ovulations in a dose-dependent manner, induced larger and more vascularized corpora lutea, but did not affect the fertility of cyclic or anestrous cows. Although eCG results in twin pregnancies, most of cows underwet embryo/fetus loss and birth a single calf.

Enteric methane output from selected herds of beef cattle raised under extensive arid rangelands

Extensively raised beef cattle contribute to the highest levels of enteric methane (CH4) gas emissions among all livestock. Expensive techniques and logistics hinder monitoring of such gas. Therefore, the objective of this study was to use an inexpensive laser methane detector (LMD) apparatus to determine the enteric CH4 levels from a herd of beef cows raised on semi-arid rangelands. A total of 24 cows were selected from Boran and Nguni cows (n = 12 per breed) from two different farms. The parities of the cows were as follows: parity 1 (n = 6), parity 2 (n = 6), parity 3 (n = 6) and parity 4 (n = 6). An observer used a hand-held LMD to measure enteric CH4 emissions plumes during the late afternoon hours when the animals were resting (either standing or lying down). Point measurements (expressed in ppm/m) were taken for six consecutive days and repeated once after every three months. The ratio of CH4 output per kilogramme DMI was not different in within-breed and between-breed in both seasons. Generally, the dry season recorded the highest CH4 output per kilogramme of live weight of cow. For example, Boran cows in parity 2 produced the highest output of 1.0 ± 0.04 g CH4 per kilogramme live weight of cow while Nguni cows in parities 1, 2 and 4 each produced 0.9 ± 0.04 g CH4 per kilogramme live weight of cow in the dry season. All the animals maintained optimal body condition scores in both seasons (ranging between the lowest of 3.2 ± 0.01 and the highest of 3.4 ± 0.01). Based on the results of the study, it is concluded that cows from both herds produced higher CH4 per kilogramme live weight of cow in the dry season while maintaining optimal body condition scores in both seasons.

Evaluation of different parameters in relation to repeat breeding of cows at the Coastal areas of Bangladesh

The aim of this study was to evaluate the presumptive factors might be responsible for repeat breeding syndrome of cows in Bangladesh. The study was conducted in different villages around the Faculty of Animal Science and Veterinary Medicine, Patuakhali Science and Technology University, Outer campus, Barisal during the period from July to September 2017. A total of 100 repeat breeder cows were evaluated considering different presumptive influencing factors such as breed, age, parity, body condition score (BCS), fetal death, retention of placenta, post-partum endometritis, abortion, dystocia and managemental practices of cows. It was found that there was no significance (p&gt;0.05) effect of parity and age of cows on the occurrence of repeat breeding syndrome in local and crossbred cows. Repeat breeding syndrome was significantly higher in BCS 2.0 to 2.5 in local breed and 3.0 to 3.5 in crossbred cows than that of other groups. In the study animals, dystocia was 4.0%, fetal death was 58.2%, retention of placenta was 57.1%, post-partum endometritis was 4.1% in crossbred cows. Cows in semi-intensive system raring had significantly (P&lt;0.05) higher (53.1%) of repeat breeding than that of others systems. Animals that were not dewormed (73.5%) and vaccinated (92.9%) had 73.5 % and 92.9% repeat breeding syndrome affected cows, respectively. It may concluded that simultaneously multiple factors such as irregular deworming and vaccination, subclinical endometritis, hormonal imbalance, early embryonic death due to low progesterone level, failure of proper heat detection and so on, might be also responsible to the occurrence of repeat breeding syndrome in cows.Res. Agric., Livest. Fish.5(1): 49-55, April 2018

Effects of Urea-Molasses Multi-nutrient Blocks (UMMB) supplementation on some production parameters of lactating Horro cows at Horro Guduru Animal Production and Research Center, western Ethiopia

The effects of dietary supplementation of urea-molasses multi nutrient block of lactating Horro cows fed Rhodes grass (chloris gayana) hay as a basal diet on milk yield, milk composition, feed intake and live weight change was studied on-station (at Horro Guduru Animal Production and Research Center of Wollega University). Sixteen cows in similar parity and lactation were randomly assigned to two groups: group A (control) and group B (UMMB-supplemented). The control group received baled Rhodes grass hay as a basal diet and small amount of concentrate; whereas the supplemented group (B) received UMMB in addition to the normal ration offered to the control group. The experiment was conducted for 60 days during the dry months. Mean daily milk yield and feed intake were higher in the cows supplemented with UMMB (P&lt;0.01) compared to the un-supplemented group. The average milk yield for control and supplemented groups are 1.62 and 2.38 respectively. On the other hands no significant differences were observed among the supplemented and control group for milk composition and body weight gain (P&gt;0.05). However the body weight gain is slightly better for the supplemented group. The increased milk production due to UMMB supplementation in this study could be attributed to the increased intakes of energy and nitrogen that was accessed through block supplementation.Keyword: UMMB Rhodes grass Milk yield Feed intake

Associations between bone and energy metabolism in cows fed diets differing in level of dietary cation-anion difference and supplemented with cholecalciferol or calcidiol

Bone-derived hormones play an important role in metabolism. This study examined the hypothesis that interactions between bone and energy metabolism, particularly those involving osteocalcin, are present in dairy cattle and have feedback mechanisms over time. Associations between metabolites in blood were examined in 32 Holstein cows blocked by parity and milk yield and randomly allocated to diets containing either 0.27 mg/kg dry matter (DM) calcidiol or cholecalciferol for an anticipated intake of 3 mg/d (120,000 IU/d) at 11 kg of DM, and positive (+130 mEq/kg DM) or negative (-130 mEq/kg DM) dietary cation-anion difference (DCAD) from 252 d of gestation to calving. Blood was sampled every 3 d, from 9 d prepartum to 30 d postpartum, and plasma concentrations of vitamin D3, 25-hydroxyvitamin D3, adiponectin, C-telopeptide of type 1 collagen (CTX1), glucose, insulin-like growth factor 1 (IGF1), insulin, undercarboxylated osteocalcin (uOC), and carboxylated osteocalcin (cOC) were determined. Feeding calcidiol compared with cholecalciferol increased plasma concentrations of 25-hydroxyvitamin D3 pre- (264.2 ± 8.0 vs. 61.3 ± 8.0 ng/mL) and postpartum (170.8 ± 6.2 vs. 51.3 ± 6.2 ng/mL) but decreased concentrations of vitamin D3 pre- (1.2 ± 0.6 vs. 14.5 ± 0.6 ng/mL) and postpartum (1.9 ± 0.4 vs. 3.2 ± 0.6 ng/mL). Prepartum, cows fed the negative DCAD diet had reduced concentrations of vitamin D3 and glucose compared with cows fed a positive DCAD. The combination of negative DCAD and cholecalciferol reduced IGF1 concentrations prepartum. The DCAD treatment had no effect on postpartum concentrations of metabolites. Nulliparous cows had increased concentrations of OC, CTX1, IGF1, glucose, and insulin compared with parous cows. Time series analysis identified associations between metabolites on the same day and over 3-d lags up to ±9 d that suggest feedback between 25-hydroxyvitamin D3 and vitamin D3 in the negative lags, indicating that 25-hydroxyvitamin D3 may exert feedback on vitamin D3 but not vice versa. We found evidence of a feedback mechanism between vitamin D3 and IGF1, with positive effect size (ES) on the same day and 3 d later, and negative ES 9 d later, that was more evident in cholecalciferol-fed cows. This suggests an important role of IGF1 in integrating bone metabolism with energy and protein metabolic pathways. Evidence of feedback was found between uOC and particularly cOC with IGF1, with positive ES on the same day but negative ES 6 d before and 6 d after. An association between uOC or cOC and IGF1 has not been previously identified in cattle and suggests that both uOC and cOC may have marked biological activity. Associations between OC and insulin identified in mice were not observed herein, although associations between OC and glucose were similar to those between IGF1 and glucose, supporting associations between glucose, OC, and IGF1. We provide further statistical evidence of crosstalk between vitamin D compounds, bone hormones, and energy metabolism in cattle. In particular, associations between uOC or cOC and IGF1 may provide links between prepartum diets and observations of prolonged increases in milk production and allow better control of peripartum metabolism.

Metabolic disorders in dairy Simmentals - prevalence risk and effect on subsequent daily milk traits

In order to analyse metabolic disorders in Simmental cows, 2.641.223 test-day records have been used. The metabolic disorders prevalence risk was indicated by the fat to protein (F/P) ratio, while the subclinical disorder was demonstrated using the F/P ratio and daily production. In terms of the ketosis prevalence risk (KPR), the highest prevalence risks occurred at the 20th lactation day in all tested cows with exception of cows in parity P4+ which experienced peak prevalence risk at 25th lactation day. A steady decrease of KPR after peak prevalence was observed in all animals except the 3rd lactation cows which experienced the second peak prevalence at the 30th lactation day, after which the prevalence risk continued to decline. The highest acidosis prevalence risk (APR) was detected among 4+ parity cows. Considering the lactation stage, the highest APR occurred within the first 10 days, with the indication from 16 to 23 %, depending on parity. The peak prevalence risk was followed by a considerable decline during the ensuing 20 days. The prevalence risk began to increase among all cows after the 25th lactation day. Furthermore, there was a considerable decrease in a daily milk yield and variation of daily milk contents due to subclinical disorders. The most noticeable drop in daily milk yield, for both ketosis/acidosis, was detected in cows in 4+ parity in the amounts of 7.45 kg/day and 2.73 kg/day respectively. There was also a production decline in the subsequent milk controls. Subclinical disorders can also substantially change daily milk contents. The daily fat content was considerably reduced by the subclinical ketosis and the same parameter was considerably increased by the subclinical acidosis. The opposite trends were detected for daily protein content. Since indication criteria was set on Holstein population and considering the fact that Simmental cows produce noticeably less, some adjustment is needed before a routine use of test-day records for early detection of metabolic disorders in dairy Simmental herds.

Association between body condition score change during the dry period and postpartum health and performance

The objectives of the current study were to determine the association between body condition score change during the dry period (ΔBCS) and postpartum health and reproductive and productive performance of Holstein cows. Data from 16,104 lactations from 9,950 parous cows from 2 dairies located in the San Joaquin Valley of California were used. Within dairy, cows were scored for body condition at dry off and parturition by the same herd workers, who were trained by veterinarians from the Veterinary Medicine Teaching and Research Center of the University of California Davis. Cows were classified as having excessive loss of BCS (ΔBCS ≤-0.75; n = 1,604), moderate loss of BCS (ΔBCS = -0.5 to -0.25; n = 6,430), no change in BCS (ΔBCS = 0; n = 4,819), and gained BCS (ΔBCS ≥0.25; n = 3,251). Data regarding morbidity, mortality, and reproductive and productive performance were recorded until 305 d postpartum or until cows were dried off or left the herd. Loss of BCS during the dry period was associated with greater incidence of uterine disease and indigestion. Additionally, loss of BCS during the dry period was associated with greater likelihood of treatment with antimicrobials, anti-inflammatories, and supportive therapy. Loss of BCS during the dry period was associated with reduced likelihood of pregnancy after the first and second postpartum inseminations. Cows that gained BCS during the dry period had greater yield of milk, fat, and protein and had reduced somatic cell linear score in the subsequent lactation. In the current study, loss of BCS during the dry period was a predisposing factor associated with health disorders and reduced productive and reproductive performance in Holstein cows.

Metabolic predictors of peri-partum diseases and their association with parity in dairy cows

The predictive values of plasma non-esterified fatty acid (NEFA), beta-hydroxybutyrate (BHB), cholesterol, albumin and calcium to predict risk of peripartum diseases in primiparous (PP) and multiparous (MP) Holstein cows was investigated. Besides it was assessed if the health status interacted with parity on body condition score and metabolic profiles during the transition period. Dairy cows (126 PP and 182 MP) from a commercial dairy free stall herd (loose-housing system) were weekly body condition scored and tail bled for metabolites determination from −3 to +4 weeks relative to calving. Peripartum diseases were diagnosed by a single trained veterinarian, while subclinical diseases (ketosis and hypocalcemia) were diagnosed at the laboratory. Cows were classified as healthy cows, cows with one event, or cows with two clinical events following a prospective observational cohort study, with only healthy cows enrolled at the beginning of the study. The largest incidence was for metritis (26.6%) followed by retained placenta (17.2%) and mastitis (15.2%) with no effect of parity, while subclinical hypocalcemia incidence was greater in MP than PP cows (43% vs 9.5%) respectively. In MP cows albumin concentrations were predictive for metritis at week −2 and for retained placenta at weeks −2 and −1, while cholesterol was predictive for mastitis at week −2, −1 and at calving. The interaction between health status and parity affected all metabolites during the transition period. This study showed a different evolution of metabolic profiles in healthy and sick cows during the transition according to parity, pointing out albumin and cholesterol as diseases predictors before calving.

Cow- and herd-level factors associated with lameness in small-scale grazing dairy herds in Brazil

This cross-sectional study aimed to assess lameness occurrence and to identify the associated risk factors in small-scale grazing dairy herds. Forty four farms (mean lactating herd size was 42 cows, SD = 11.2, range: 28–74) located in the south of Brazil were visited twice, approximately 4 months apart, in 2015. Locomotion was scored in 1633 and 1836 cows at the first and second visit, respectively. Potential risk factors for lameness were assessed through inspection of cows and facilities, and a questionnaire for farmers about herd management practices. Multilevel logistic regressions, using herd as random effect, were fitted to investigate the cow-level risk factors for accumulated incident (not lame at the first visit but lame on the second), chronic (lame on both visits) and recovered (lame at the first visit but sound on the second) cases of lameness. A multilevel linear regression, using municipality as a random effect, was fitted for herd-level analysis. Cumulative lameness incidence between two visits (1110 cows in 41 herds) was 29.6% (range: 0–80); lameness prevalence (n = 44 herds) was 31% (10–70) and 35% (5–76) at the first and second visits, respectively. The odds of incident cases were greater in Holstein cows [odds ratio (OR) = 4.0, 95% confidence interval 2.1–7.6] compared with Jerseys, in cows in parities 2–3 (OR 2.5, 1.4–4.4) or >3 (OR 6.6, 3.3–13.1) relative to parity 1, in cows having a low body condition score (BCS) of 2–2.75 or 3 on the first visit (OR 2, 1.1–3.7), and in cows with observed hoof abnormalities (OR 2.5, 1.3–4.7). Similar associations were found for chronic cases, with Holstein and crossbred cows having greater odds of lameness, compared to Jersey, and chronic cases being more likely in cows with increasing parity, with BCS at first visit of 2–2.75, and with presence of hoof abnormalities. Jersey or crossbred cows (OR 3.2, 1.3–8.1) and cows in parity 1–2 (OR 3.6, 1.6–8.4) had higher probability of recovery from lameness. Having a herd composed of Holstein cows was associated with 13.5% (CI 4.3–22.8) greater incidence of lameness (n = 35). For every 1 km/h increase in the average speed of movement of the herd to or from milking, lameness incidence increased by 5% (CI 0.1–10). Given that the occurrence of lameness was high there is great opportunity to reduce lameness in this population. This study highlights some management and prevention practices that may reduce lameness in these grazing herds.