Performance Evaluation of Manure Nitrogen Output Models Suitable for Lactating Dairy Cows in China

2018 ◽  
Vol 61 (5) ◽  
pp. 1713-1727
Author(s):  
Ruilan Dong ◽  
Hongmin Dong ◽  
Karen A. Beauchemin ◽  
Hongwei Xin
Keyword(s):  
Dairy Cattle ◽  
Dairy Cows ◽  
Prediction Models ◽  
Empirical Models ◽  
Nitrogen Excretion ◽  
Data Set ◽  
Total N ◽  
Lactating Dairy Cows ◽  
Wide Range ◽  
Best Fit

Abstract. Manure nitrogen (N) output from dairy cattle is a major environmental concern in China. Various empirical models are available to predict manure N output from dairy cattle, but the accuracy and precision of these models has not been assessed for Chinese conditions. The objective of this study was to evaluate the performance of extant models that predict different forms of manure N output for lactating dairy cows in China with the aim of identifying the best-fit and most suitable prediction models. A total of 35 empirical models were evaluated for their ability to predict N excretion of dairy cows in China fed a wide range of diets. The data set consisted of 99 treatment means from 32 publications with information on animal and dietary characteristics and N output flows. Performance of the models was evaluated using root mean square prediction error (RMSPE) and concordance correlation coefficient (CCC) analysis. A model (eq. 19) based on N intake (NI) was selected as best for predicting fecal N excretion (RMSPE = 15.8% and CCC = 0.75). Another model that also used NI as an input variable was most suitable for predicting urinary N (RMSPE = 26.0% and CCC = 0.63, eq. 14) and total N (RMSPE = 15.8% and CCC = 0.81, eq. 31). Models predicting urinary urea N (UUN) and urinary N / total N performed poorly. Overall, the deviation of the regression line from the equality line (y = x line) for even the best-fit urinary, fecal, and total N excretion models demonstrated the need to develop improved models for use under Chinese conditions. Using N output data from dairy cows in China to develop manure N output models may help improve environmental stewardship of the dairy industry in China. Keywords: Dairy cows, Evaluation, Manures, Model performance, Nitrogen excretion.

Calibration of Voting-Based Helpfulness Measurement for Online Reviews: An Iterative Bayesian Probability Approach

2020 ◽  
Author(s):  
Xunhua Guo ◽  
Guoqing Chen ◽  
Cong Wang ◽  
Qiang Wei ◽  
Zunqiang Zhang
Keyword(s):  
User Study ◽  
Prediction Models ◽  
Online Reviews ◽  
User Generated Content ◽  
Bayesian Probability ◽  
Social Media Analytics ◽  
Science Literature ◽  
Data Set ◽  
Novel Approach ◽  
Wide Range

Voting mechanisms are widely adopted for evaluating the quality and credibility of user-generated content, such as online product reviews. For the reviews that do not receive sufficient votes, techniques and models are developed to automatically assess their helpfulness levels. Existing methods serving this purpose are mostly centered on feature analysis, ignoring the information conveyed in the frequencies and patterns of user votes. Consequently, the accuracy of helpfulness measurement is limited. Inspired by related findings from prediction theories and consumer behavior research, we propose a novel approach characterized by the technique of iterative Bayesian distribution estimation, aiming to more accurately measure the helpfulness levels of reviews used for training prediction models. Using synthetic data and a real-world data set involving 1.67 million reviews and 5.18 million votes from Amazon, a simulation experiment and a two-stage data experiment show that the proposed approach outperforms existing methods on accuracy measures. Moreover, an out-of-sample user study is conducted on Amazon Mechanical Turk. The results further illustrate the predictive power of the new approach. Practically, the research contributes to e-commerce by providing an enhanced method for exploiting the value of user-generated content. Academically, we contribute to the design science literature with a novel approach that may be adapted to a wide range of research topics, such as recommender systems and social media analytics.

The effects of concentrate energy source on silage feeding behaviour and energy utilization by lactating dairy cows offered grass silages with differing intake characteristics

1998 ◽  
Vol 67 (2) ◽  
pp. 225-236 ◽  
Author(s):  
T. W. J. Keady ◽  
C. S. Mayne
Keyword(s):  
Energy Source ◽  
Dairy Cows ◽  
Feeding Behaviour ◽  
Energy Utilization ◽  
Energy Output ◽  
Design Experiment ◽  
Concentrate Energy ◽  
Lactating Dairy Cows ◽  
Wide Range ◽  
Concentrate Energy Source

AbstractThe effects of concentrate energy source on feeding behaviour and energy utilization, when offered with grass silages of differing intake characteristics, were studied in lactating dairy cows. A total of five silages, which differed in fermentation and intake characteristics, were prepared. Silages A, B and D and silages C and E were harvested from primary regrowths and secondary regrowths respectively of predominantly perennial ryegrass swards. Herbage was ensiled either pre-wilted or unwilted and either untreated or treated with a bacterial inoculant or formic acid based additives. Five concentrates (0s, 25s, 50s, 75s and 100s) were formulated to contain similar concentrations of crude protein, effective rumen degradable protein and metabolizable energy (ME) but using different carbohydrate sources to achieve a wide range of starch concentrations. The silages were offered ad libitum, supplemented with 10 kg concentrates per head per day. In experiment 1, a partially balanced change-over design experiment involving 50 lactating dairy cows was undertaken to examine the effects of concentrate energy source on silage feeding behaviour. Silages A, B, C, D and E were each supplemented with concentrates Os, 25s, 50s, 75s and 100s. Concentrate energy source did not alter (P > 0·05) silage feeding behaviour. The number of meals per day decreased (P < 0·01) as silage dry-matter concentration increased. Experiment 2, a completely randomized experiment involving 18 lactating dairy cows, was undertaken to examine the effects of concentrate energy source on energy utilization with cows offered silages B, C and D. These were supplemented with 10 kg/day of concentrates Os, 50s and 100s. Concentrate energy source had little effect (P > 0·05) on ME intake, energy output or on the efficiency of utilization of ME for lactation (k1). In experiment 3, the effect of concentrate energy source on silage preference was examined in a factorial design experiment involving 12 lactating dairy cows. Silages B, C and D were supplemented with concentrates Os, 50s and 100s. Concentrate energy source did not alter (P > 0·05) silage preference. It is concluded that with silages of differing fermentation and intake characteristics but of similar digestibility, concentrate energy source had no effect on feeding behaviour, silage preference or energy utilization. Furthermore there was no evidence of concentrate energy source by silage type interactions on silage feeding behaviour and preference, or energy utilization.

10 EFFECT OF USING PROTECTIVE AI COVER SHEATHS ON FERTILITY OF LACTATING DAIRY COWS

2010 ◽  
Vol 22 (1) ◽  
pp. 163
Author(s):  
S. Bas ◽  
A. Hoet ◽  
P. Rajala-Schultz ◽  
D. Sanders ◽  
G. M. Schuenemann
Keyword(s):  
Dairy Cattle ◽  
Dairy Cows ◽  
Dairy Farm ◽  
Cost Effective ◽  
Reproductive Outcomes ◽  
Lactating Cows ◽  
Lactating Dairy Cows ◽  
Herd Milk ◽  
Underlying Mechanisms ◽  
The Moment

An adequate and clean artificial insemination (AI) technique is recommended to maximize reproductive outcomes in dairy cattle. The objective of this study was to evaluate the effectiveness of using protective sheaths (PS; Continental Plastic Inc., Delavan, WI, USA) to minimize contamination of the AI catheter (AIC) on pregnancies per AI (P/AI) in lactating dairy cattle. A previous study reported no improvement on cattle fertility when using PS during first service AI (King et al. 1984 Can. Vet. J. 25, 327). Lactating cows housed in free-stall barns on a commercial dairy farm with a rolling herd milk production average of 10.140 kg were presynchronized with 2 injections of PGF2α (25 mg; Lutalyse, Pharmacia & Upjohn, Kalamazoo, MI, USA) given 14 days apart (starting at 26 ± 3 d postpartum) followed by Ovsynch [OV; GnRH-7 d-PGF2α-56 h-GnRH-16 h-timed-AI(TAI)] 12 days later. Cows presenting signs of standing heat any time during the protocol received AI, whereas the remaining animals were subjected to TAI16 h after second OV GnRH (100 μg; Cystorelin, Merial, Duluth, GA, USA). At the moment of AI (one AI technician), 996 services from lactating dairy cows were randomly assigned to 1 of the 2 groups; with (TRT, n = 487) or without (CON, n = 509) the use of PS. In the TRT group, the AIC protected with a PS was introduced into the vagina; once in the cranial portion of the vagina adjacent to the cervical os, the PS was pulled back and only the AIC was manipulated through the cervix into the uterine body for semen deposition. In the CON group, cows received AI without the PS. Additionally, sterile cotton swab (BD, Franklin Lakes, NJ, USA) samples were taken from AIC (n = 51) after AI from both treatment groups. Pregnancy diagnosis was determined by ultrasonography 42 ± 3 d after AI. Data analyses were performed using GLIMMIX (P/AI) and FREQ (culture) procedures of SAS (SAS Institute Inc., Cary, NC, USA). Cultured swab samples revealed that the use of PS was effective in minimizing contamination of the AIC (bacterial growth on AIC; TRT = 57.7% v. CON = 100%; P < 0.0002). Overall, the proportion of cows pregnant (all services) was greater (P = 0.03) for cows in TRT (42.7 ± 2.2%) compared with CON group (36.1 ± 2.1%). For first services postpartum, P/AI did not differ (P = 0.87) between CON (43.01 ± 4.4%) and TRT (43.8 ± 4.6%) groups. However, P/AI for second or greater services (≥2S) were greater (P = 0.007) in TRT (43.8 ± 2.9%) than in CON cows (32.3 ± 2.6%). Results from this study suggested that the use of PS during AI improved P/AI for ≥2S in lactating dairy cows. Performing a clean AI technique through the use of PS may be a cost-effective strategy to improve reproductive outcomes in dairy cattle. Further investigation is needed under various reproductive management conditions to confirm and determine the underlying mechanisms for these findings. Authors thank Coba/Select Sires Inc. (Columbus, OH, USA) for the donation of the AI protector sheaths, Meerland Dairy for providing the animals and Brian Alkire (Coba’s AI technician).

Evaluation of solvent and expeller linseed meals as protein sources for dairy cattle

1994 ◽  
Vol 74 (3) ◽  
pp. 479-485 ◽  
Author(s):  
G. R. Khorasani ◽  
J. J. Kennelly ◽  
P. H. Robinson
Keyword(s):  
Dairy Cattle ◽  
Dairy Cows ◽  
Soybean Meal ◽  
Nutritive Value ◽  
Canola Meal ◽  
Linseed Meal ◽  
Protein Supplements ◽  
Lactating Dairy Cows

The objectives of the present study were to evaluate the nutritive value of expeller linseed meal (ELM) and solvent linseed meal (SLM) as protein supplements for lactating dairy cows utilizing analytical and in situ procedures, and determine the in vivo nutritive value of the most promising linseed meal in diets containing either barley or corn-based concentrate. Canola meal (CM) and soybean meal (SBM) were included in the evaluative stage for comparative purposes. Linseed meals contained 37.8 and 35.4% crude protein (CP); 22.6 and 25.9% neutral detergent fibre (NDF); and 12.9 and 7.1% crude fat for ELM and SLM, respectively. Rate and extent of dry matter, NDF, and CP digestion, as determined by the rumen in situ technique, indicated that ruminal digestibility of SLM was similar to that observed for CM, but ruminal escape of ELM protein was higher than for CM. The proportion of ruminal escape protein was similar for SLM, CM and SBM. Total tract CP digestibilities of SLM and CM were similar to and lower than those observed for ELM and SBM. Soybean meal had the highest total tract CP digestibility. Based on results of the analytical and in situ procedures, SLM was selected for evaluation in the in vivo experiment. Results indicated that SLM did not have any deleterious effect on digestion of other components of the diet, and parameters of rumen fermentation indicated similar digestion patterns for cows fed SLM and CM. Overall, results indicate that SLM has potential as a replacement for CM or SBM in diets of dairy cattle. It was also concluded that replacement of barley with corn does not influence the nutritive value of SLM for dairy cows. Key words: Linseed meal, canola meal, dairy cattle

Maize silage as a supplement for pasture-fed dairy cows in early and late lactation

1995 ◽  
Vol 35 (1) ◽  
pp. 19 ◽  
Author(s):  
CR Stockdale
Keyword(s):  
Dairy Cows ◽  
Dietary Protein ◽  
Milk Fat ◽  
Dry Matter ◽  
Early Lactation ◽  
Maize Silage ◽  
Marginal Return ◽  
Lactating Dairy Cows ◽  
Wide Range ◽  
Yield Responses

Eight experiments were conducted over 2 years with 92 lactating dairy cows individually fed various combinations of irrigated perennial pasture and maize silage in an indoor feeding facility. Responses to different amounts of maize silage and pasture in early and late lactation were measured. Daily pasture intake ranged from 6.2 to 12.4 kg dry matter (DM)/cow, while maize silage intake ranged from 0 to 12.4 kg DM/cow. The marginal return to feeding maize silage at up to 5 kg DM/cow.day to cows in early lactation eating about 7 kg DM/day of pasture as their basal ration was 0.89 kg extra milk for each kg DM maize silage eaten. In late lactation, this was reduced to 0.63 kg milk/kg DM. Milk yield responses to maize silage at both stages of lactation were lower at higher levels of pasture feeding. Although milk fat content was maintained over a wide range of maize silage, feeding large quantities of maize silage in early lactation was detrimental to milk production. The likely explanation for poor animal performance at the high levels of maize silage was dietary protein insufficiency.

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