Predicting branch characteristics of Norway spruce (Picea abies (L.) Karst.) from simple stand and tree measurements   总被引：2，自引：0，他引：2  

Makinen  Harri; Ojansuu  Risto; Sairanen  Pentti; Yli-Kojola  Hannu 《Forestry》2003,76(5):525-546

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Cow‐specific diet digestibility predictions based on near‐infrared reflectance spectroscopy scans of faecal samples          下载免费PDF全文

T. Mehtiö  M. Rinne  L. Nyholm  P. Mäntysaari  A. Sairanen  E.A. Mäntysaari  T. Pitkänen  M.H. Lidauer 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2016,133(2):115-125

This study was designed to obtain information on prediction of diet digestibility from near‐infrared reflectance spectroscopy (NIRS) scans of faecal spot samples from dairy cows at different stages of lactation and to develop a faecal sampling protocol. NIRS was used to predict diet organic matter digestibility (OMD) and indigestible neutral detergent fibre content (iNDF) from faecal samples, and dry matter digestibility (DMD) using iNDF in feed and faecal samples as an internal marker. Acid‐insoluble ash (AIA) as an internal digestibility marker was used as a reference method to evaluate the reliability of NIRS predictions. Feed and composite faecal samples were collected from 44 cows at approximately 50, 150 and 250 days in milk (DIM). The estimated standard deviation for cow‐specific organic matter digestibility analysed by AIA was 12.3 g/kg, which is small considering that the average was 724 g/kg. The phenotypic correlation between direct faecal OMD prediction by NIRS and OMD by AIA over the lactation was 0.51. The low repeatability and small variability estimates for direct OMD predictions by NIRS were not accurate enough to quantify small differences in OMD between cows. In contrast to OMD, the repeatability estimates for DMD by iNDF and especially for direct faecal iNDF predictions were 0.32 and 0.46, respectively, indicating that developing of NIRS predictions for cow‐specific digestibility is possible. A data subset of 20 cows with daily individual faecal samples was used to develop an on‐farm sampling protocol. Based on the assessment of correlations between individual sample combinations and composite samples as well as repeatability estimates for individual sample combinations, we found that collecting up to three individual samples yields a representative composite sample. Collection of samples from all the cows of a herd every third month might be a good choice, because it would yield a better accuracy.  相似文献   

Concentrate supplementation responses of the pasture-fed dairy cow     

Auvo Sairanen  Hannele Khalili  Perttu Virkajrvi 《Livestock Science》2006,104(3):292-302

The aim of this study was to investigate the effects of increasing amounts of cereal-based concentrate on milk production. The study consisted of a series of three separate experiments in which cows were grazed in intensive rotation on timothy-meadow fescue pasture. In Experiment 1, 28 multiparous Holstein–Friesian cows received 0, 3, 6 and 9 kg concentrate in a cross-over designed trial with a fixed daily herbage allowance of 21 kg DM/cow. The energy-corrected milk yield increased linearly 0.84 kg/kg DM (P < 0.001), up to the 9 kg concentrate level. The milk fat (P < 0.001) and urea (P < 0.001) content decreased linearly (0.41 g/kg DM and 0.15 mmol/kg DM, respectively). The milk protein content tended (P = 0.08) to increase 0.10 g/kg DM with increasing supplementation.

In Experiment 2, 17 primiparous cows and 28 multiparous cows were used in a randomized-block designed trial with 3, 6 and 9 kg concentrate supplementation and a fixed 25 kg DM herbage allowance. The energy corrected milk yield increased linearly (P < 0.01) 0.67 kg/kg DM, whereas the milk urea content decreased linearly (P < 0.001) 0.27 mmol/kg DM. The milk protein content increased and the fat content decreased, but these differences were not significant.

In Experiment 3, a cross-over design was used to assess the response to concentrate supplementation of 24 multiparous cows (treatments: 6, 9 and 12 kg; fixed herbage allowance 25 kg DM) and 12 primiparous cows (treatments: 4, 7 and 10 kg; herbage allowance > 25 kg DM). The energy-corrected milk yield of the multiparous cows varied quadratically (P_quad < 0.001; 30.0, 32.5 and 32.2 kg for 6, 9 and 12 kg supplementation, respectively). Supplementation linearly decreased the urea (P < 0.001) 0.13 mmol/kg DM and fat (P < 0.001) 0.46 g/kg DM contents. The milk fat content also varied quadratically, showing the lowest content with the 12 kg level (P_quad < 0.05; 37.3, 37.3 and 34.9 g/kg for 6, 9 and 12 kg supplementation, respectively). The energy-corrected milk yield of the primiparous cows increased linearly (P < 0.001) 0.54 kg/kg DM up to 10 kg supplementation, whereas the milk urea (P < 0.001) and fat contents decreased linearly (P < 0.01) by 0.19 mmol/kg DM and 0.61 g/kg DM, respectively.

The results showed that the milk response remained linear up to the 9 kg supplementation level, but the highest level of supplementation resulted in only a marginal increase in milk yield. There was no interaction between season and milk or milk protein yield, which indicates that it is possible to maintain stable grazing conditions during the main grazing season in Nordic latitudes. The results support to some extent the hypothesis that the marginal milk response to supplementation increases with increasing milk production.  相似文献   

Modelling feed intake and milk yield responses to different grass ley harvesting strategies     

Degong Pang  Sophie J. Krizsan  Auvo Sairanen  Juha Nousiainen  Pekka Huhtanen 《Grass and Forage Science》2019,74(3):509-524

A meta‐analysis of feeding trials using grass silages was conducted to predict production responses for dairy cows fed grass silage. They were divided into two subsets: 69 diets from 11 studies were used for comparison of silages made from primary growth and regrowth grass (harvesting subset), and another 157 diets from 24 studies were used for comparison of digestibility influenced by the maturity of grass ensiled (D‐value, digestible organic matter in dry matter) (maturity subset). The minimum prerequisite for an experiment to be included in the data set was that milk production, feed intake, silage characteristics and concentrate ingredients were reported. Both subsets were analysed using the mixed model procedures of SAS. The mean response in dry‐matter intake (DMI) and silage DMI to improved silage D‐value was 0.0175 and 0.0161 kg per unit D‐value (g/kg DM) respectively. The average increase in milk and energy‐corrected milk yield was 0.30 and 0.37 kg per 10‐unit increase in silage D‐value respectively. Milk protein concentration increased, and fat concentration tended to increase with enhanced silage D‐value. Each 10‐unit increase in D‐value reduced milk yield by 0.092 kg at a given dietary metabolizable energy intake (MEI), suggesting that the ME concentration of high D‐value silages was overestimated. Cows fed regrowth silage produced 0.55 kg/day more energy‐corrected milk than those fed primary growth silage at a given dietary MEI. The prediction models can be used to improve ration formulation systems or incorporated into economic models for optimizing milk production in various farming systems.  相似文献