Fourier transform infrared spectroscopy of milk samples as a tool to estimate energy balance, energy- and dry matter intake in lactating dairy cows.

The objective of the study was to evaluate the potential of Fourier transform infrared spectroscopy (FTIR) analysis of milk samples to predict body energy status and related traits (energy balance (EB), dry matter intake (DMI) and efficient energy intake (EEI)) in lactating dairy cows. The data included 2371 milk samples from 63 Norwegian Red dairy cows collected during the first 105 days in milk (DIM). To predict the body energy status traits, calibration models were developed using Partial Least Squares Regression (PLSR). Calibration models were established using split-sample (leave-one cow-out) cross-validation approach and validated using an external test set. The PLSR method was implemented using just the FTIR spectra or using the FTIR together with milk yield (MY) or concentrate intake (CONCTR) as predictors of traits. Analyses were conducted for the entire first 105 DIM and separately for the two lactation periods: 5 ≤ DIM ≤ 55 and 55 < DIM ≤ 105. To test the models, an external validation using an independent test set was performed. Predictions depending on the parity (1st, 2nd and 3rd-to 6th parities) in early lactation were also investigated. Accuracy of prediction (r) for both cross-validation and external test set was defined as the correlation between the predicted and observed values for body energy status traits. Analyzing FTIR in combination with MY by PLSR, resulted in relatively high r-values to estimate EB (r = 0.63), DMI (r = 0.83), EEI (r = 0.84) using an external validation. Only moderate correlations between FTIR spectra and traits like EB, EEI and dry matter intake (DMI) have so far been published. Our hypothesis was that improvements in the FTIR predictions of EB, EEI and DMI can be obtained by (1) stratification into different stages of lactations and different parities, or (2) by adding additional information on milking and feeding traits. Stratification of the lactation stages improved predictions compared with the analyses including all data 5 ≤ DIM ≤105. The accuracy was improved if additional data (MY or CONCTR) were included in the prediction model. Furthermore, stratification into parity groups, improved the predictions of body energy status. Our results show that FTIR spectral data combined with MY or CONCTR can be used to obtain improved estimation of body energy status compared to only using the FTIR spectra in Norwegian Red dairy cattle. The best prediction results were achieved using FTIR spectra together with MY for early lactation. The results obtained in the study suggest that the modeling approach used in this paper can be considered as a viable method for predicting an individual cow's energy status.

Treatment and survival of Norwegian cattle after uterine prolapse.

BACKGROUND: Bovine uterine prolapse is a sporadic but life-threatening postpartum condition. The aims of this study were; (i) to determine which clinical findings determined the likelihood of treatment vs. culling, (ii) to identify the treatment methods currently employed by Norwegian veterinary surgeons and evaluate their effect on survival, (iii) to determine if clinical findings at the time of treatment could be used to determine prognosis. Practicing veterinary surgeons in Norway were contacted and asked to fill out a questionnaire on cases of bovine uterine prolapse they attended between February and October 2012. The questionnaires gathered data on signalment, clinical presentation, treatment, and outcome. These data were supplemented with culling data from the Norwegian Dairy and Beef Herd Recording Systems. The chi-squared test and logistic regression modelling was performed to identify likelihood of treatment and cox proportional hazard modelling was performed to identify the hazard of death after treatment. RESULTS: Data from 126 cases of bovine uterine prolapse were collected (78 beef and 48 dairy cows). Twenty-six cows (21%) were emergency slaughtered, or underwent euthanasia, without treatment. Of the remaining 100 cases amputation of the uterus was performed once and repositioning was performed in 99 cases. Survival data were missing from 2 of the cases that had undergone treatment leaving a study sample of 97 cases (64 beef and 33 dairy cows). Multivariable logistic regression analysis of the explanatory variables showed that beef cows were more likely to be treated than dairy cows (OR = 0.32, 95% CI 0.13 to 0.81, P = 0.017) and that cows with a significantly oedematous or traumatised uterus were less likely to be treated (OR = 0.26, 95% CI 0.10 to 0.67, P = 0.006). Treatment methods amongst Norwegian practitioners were broadly similar. In a multivariable model cows general clinical state at time of treatment was positively correlated with survival (HR = 0.29, 95% CI 0.29 to 0.73, P = 0.008) and a history of a vaginal prolapse prepartum increased the hazard of death (HR = 2.31, 95% CI 1.08 to 4.95, P = 0.031) in the first 30 days after treatment of a uterine prolapse. In the first 180 days after treatment only veterinary assessment of a cows' general clinical state was correlated with hazard of death (HR = 0.432, 95% CI 0.20 to 0.91, P = 0.046). CONCLUSIONS: This study shows that the production system and extent of uterine damage affect the likelihood of treatment, and that practitioners use similar treatment methods. A cows' general clinical state at time of treatment was positively correlated with survival, and a history of a vaginal prolapse prepartum increased the hazard of death in the first 30 days after treatment of a uterine prolapse.

Time of insemination in relation to pregnancy rates in beef cattle after oestrus detection with automated activity monitoring system.

BACKGROUND: The timing of artificial insemination is critical to achieve acceptable results in cattle production systems. Over the past 60 years the length and expression of oestrus in dairy cattle has altered. Recent studies have indicated the optimal timing for insemination after the commencement of oestrus may now be earlier than traditional recommendations in beef cattle, as is the case in dairy cattle. The aim of the current study was to evaluate the effect of time from onset of oestrus [as determined by an automated activity monitoring system (AAMS)] to artificial insemination (AI) on pregnancy outcome in Norwegian beef cattle. Five commercial beef suckler herds participated in a cohort study by providing data on the time of AAMS alarm and time of AI. Blood sampling on the day of AI was performed and serum progesterone concentration measured. Pregnancy detection was performed by transrectal ultrasonography and aging of the fetus performed when necessary. A mixed logistic regression model was fitted to study the effect of time from AAMS alarm to AI on pregnancy outcome. Time categories used in the model were < 12 h, 12-24 h, and > 24 h. RESULTS: AI periods (n = 229) with serum progesterone concentration < 1 ng/mL were available for analysis. Overall pregnancy risk per AI for the whole study period was 65.5%, with an inter-herd variation from 10 to 91%. Median time elapsed from AAMS alarm to AI was 17.75 h. Herd affected pregnancy outcome (P = 0.001), while breed and parity status (heifer/cow) did not. The time category closer to AAMS alarm 0-12 h showed a numerically lower pregnancy risk as compared to the baseline group which had AI 12-24 h after onset of oestrus. CONCLUSION: This study found no evidence to support a change in the recommended timing of AI in beef suckler cows.

Pilot study investigating estrus length and estrus behavior in Norwegian Red cattle on a commercial dairy farm.

Introduction: Norwegian Red has been shown to have high levels of estrus behavior under experimental conditions. However, the estrus behaviors of Norwegian Red cows have not been studied under commercial conditions. Methods: A herd of 89 Norwegian Red cows housed in free stalls on concrete, slatted floors, were continuously video monitored for 21 days. Ovarian cyclicity was confirmed in a final study sample group (n = 18) using milk progesterone concentrations. All mounting and standing activities were recorded, and the duration of mount estrus, standing estrus and the differences between these; prestand and poststand, were determined. The cycle stages metestrus, diestrus and proestrus were estimated based on the starting time and ending time of mount estrus. Results: All cows in the final study sample group exhibited the primary estrus sign, 'standing to be mounted' during estrus. Two (11%), eleven (61%) and six (33%) cows exhibited the behavior 'standing to be mounted' during metestrus, diestrus and proestrus, respectively. The number of mounts initiated by individual cows was higher during mount and stand estrus than during the rest of the estrous cycle. This study reports a median duration of mount estrus and stand estrus of 21.0 h (interquartile range (IQR) 15.0 to 27.3) and 14.3 h (IQR 12.0 to 18.8), respectively. The median counts per hour of all mount behaviors were 8.6 (IQR 5.6 to 11.3), 1.51 (IQR 0.3 to 3.8) and 1.7 (IQR 0.8 to 6.0) for standing estrus, prestand and poststand, respectively. Discussion: This study shows that under commercial conditions the Norwegian Red cow displays a high level of mount and stand activity associated with estrus.

Occurrence and reasons for on-farm emergency slaughter of cattle in Norway.

On-farm emergency slaughter (OFES) accounts for more than 4% of all cattle slaughter in Norway. The practice raises questions about animal welfare, public health, and the sustainability of cattle production. The objective of this study was to describe the reasons for OFES as stated on the OFES veterinary certificate. Veterinary certificates for OFES for each animal slaughtered in four chosen slaughterhouses from 4 months (January-April-July-October) in 2018 were transcribed into a database. Secondary data were extracted from national cattle databases and used to supplement primary data with information on breed, sex, and birth date. Breeds were divided into dairy and beef cattle. The reasons for slaughter were reported in text on the certificates and were categorized in the study into 5 reasons: recumbency, mammary gland, obstetrics, locomotion, and other, with a total of 20 subcategories for detail. In total, 2,229 forms were included in the study. Thirteen breeds were represented, although dominated by Norwegian Red within dairy and crossbreed within beef. Of the cattle in the study, 46% were slaughtered for locomotion reasons, thereof almost half for lameness. Furthermore, 23% of the cattle in the study were slaughtered for recumbency and 17% for prolapse or dystocia. A higher proportion of dairy cows were slaughtered because of reasons related to mammary glands than beef cows, 10 and 2%, respectively. Almost 30% of beef cows were slaughtered for obstetrics reasons compared to 12% of dairy cows. The results of this study shed light on the reasons for OFES, which is highly relevant to greater discussions of sustainability in cattle production and animal welfare related to on-farm mortality.

Overview of the practices of on-farm emergency slaughter of cattle in the Nordic countries.

On farm mortality is an increasing problem in cattle production systems in the Nordic countries. It represents an economic loss to the farmer and raises questions of sustainability, food waste and animal welfare. On-farm emergency slaughter (OFES) represents, in some situations, an opportunity for a farmer to salvage some of the economic value from an animal that cannot be transported to a slaughterhouse. The basis of the regulation of OFES in the Nordic countries originates largely from legislation from the European Union. However, this review has found that the availability and practice of OFES in the Nordic countries differs considerably. For example, in Norway 4.2% of all cattle slaughter is OFES, whilst in Iceland OFES has never been recorded. National food safety authorities have issued differing regulations and guidelines regarding the suitability of sick and injured animals for OFES. This review shows there is a paucity of data regarding the incidence and reasons for the use of OFES of cattle in the Nordic countries and points out the need for more investigation into this area to improve veterinary education, consumer protection and animal welfare.

Reproductive Performance in a Selected Sample of Dairy Farms in Una-Sana Canton, Bosnia and Herzegovina.

BACKGROUND: The production of milk and dairy products and their placement on the market represent a constant profit for the farmers/producers in Bosnia and Herzegovina (BH). The profitable operation of the dairy farms is influenced by the reproductive performance of the lactating animals. This study assessed individual animal reproductive characteristics in selected dairy farms and described their reproductive performance indicators. RESULTS: The median age at first insemination was 493 days (5th-95th percentile range 429-840), while the age at first calving was 802 days (5th-95th percentile range 708-1168). The median pregnancy proportion at first insemination was 40% (5th-95th percentile range 17-62), while the cumulative pregnancy rate calculated at day-60, day-80, day-100, and day-120 showed that approximately 64% of all pregnancies happened before day-120. The calculated interservice intervals showed that approximately 69% of the repeat breeding animals came back to the oestrus in the period of 18 to 24 days. This is an indication of very good oestrus detection in selected dairy farms. The mean number of services per pregnancy was 2.61 (range 1-12). The median calving-to-first-insemination interval was 62.5 days (5th-95th percentile range 16-408). The calving-to-conception interval was 101 day (5th-95th percentile range 36-506). Finally, the calving interval was 385 days (5th-95th percentile range 329-773). CONCLUSIONS: There is a need for an organised, regular, and more comprehensive recording system for the reproduction of dairy cattle among dairy farms in Una-Sana Canton. The calculated reproductive measures indicated an undulant trend in reproductive performance among selected dairy farms in Una-Sana Canton. Knowing the apparent reproductive indicators described in this study, the farmers and veterinary authorities may identify and correct areas in their management that contribute to the reproductive underperformance.