Milk production based on grass/clover silage and cereal grain

The aim with the present experiment was to study the effect of exclusion of protein concentrates in the diet for dairy cows using silage with high or low crude protein contents. The response was evaluated in terms of yield and composition of milk and feed intake. Economic calculations of milk income minus feed cost were made using the result of the experiment and current prices of feed and milk in spring 2013

Methods for examining fungal prevalence in haylage

The production of organic milk is increasing in Sweden. In 2012 it made up 12.7% of total milk delivered. One constraining factor in the production is the scarcity of protein- rich feedstuffs. The price of protein- rich concentrates certified as organic is high, creating a growing interest in home-grown protein- rich feeds. Field beans, Vicia faba, is an attractive crop for organic cultivation and should have the potential to add valuable protein to diets for ruminants. Being a legume, field beans can fix atmospherics nitrogen and are also appreciated as a preceding crop in the crop rotation system due to its deep root system. However, rumen solubility of the protein fraction in field beans is high, as in most other home-grown crops. When feeding a diet based on grass-clover silage and concentrates based on wheat, barley or oats, all feeds consist of easily degrade protein. A protein supplement with higher resistance towards rumen degradation combined with a high total digestibility would be desirable

Minskade förluster vid ensilering av grovfoder

Förluster vid ensilering har uppmätts i laboratorieskala och i fullskala på gårdar. Förluster av kasserat ensilage på gårdarna utgjorde ca 2 % av torrsubstansen (ts) medan osynliga förluster i form av koldioxid och värme uppmättes till 10–20 % i plan-, slang- och tornsilor och ca 1 % i rundbalar. Laboratorieförsök visar att den långa tid som stora silor står öppna under uttagstiden utgjorde en viktig orsak till stora förluster. En mer omfattande packning av grönmassan vid inläggning samt bättre täckning verkade kunna minska förlusterna i plansilor. Projektet har inte kunnat påvisa att temperaturen i plansilor är en trovärdig mätare av torrsubstansförlusten. Inte heller har halten eller arten av jäst i grönmassan kunnat knytas till förluster eller lagringsstabilitet. Silons täthet och ensilagets ts-halt var de faktorer som påverkade lagringsstabiliteten mest. Hög ts-halt och otät silo under lagringen ger ett ensilage med väsentligt kortare hållbarhet efter öppningen. Studien på gårdar visar att en bättre packad och tätare silo kan leda till 10 procentenheter mindre ts-förlust vilket motsvarar ett fodervärde av ca 25 000 kronor för en normalstor plansilo

Relation between seal integrity and hygienic quality in silage bales and differences between baling techniques

Bale silage is widely used in many countries on small and medium sized cattle farms and for horses. About 8 million bales are produced annually in Sweden, corresponding to approximately 45% of the total silage production of 4.5 million ton DM (Pettersson, 2006; SCB, 2016). Sufficient protection against air intrusion during storage is essential in all ensiling, and since introduction of the round bale technique, seal integrity of bales has continuously been improved. When the technique to make silage in bales was introduced, bales were inserted in plastic bags but this was soon replaced by the stretch film technique. During the last two decades, the polyethylene industry has continuously developed new stretch film qualities which have been tested on round and square bales of grass at the Department of Animal Nutrition and Management, SLU. Degree of air-tightness of bales, seal integrity have been measured in these studies by the time it takes for an induced under-pressure to disappear in the bales. Silage quality has thereafter been analyzed in terms of standard chemical analysis of fermentation parameters such as pH, ammonia nitrogen and volatile fatty acids and hygienic standard in terms of cell counts of yeast and mould. The main purpose of the present work was to evaluate the relation between seal integrity, measured as pressure equalization time, and fermentation parameters and hygienic quality. Furthermore, data was used in a meta-analysis to study how silage quality was affected by number of stretch film layers and by using round- or square bales

Effects of delayed sealing during silo filling

Swedish farmers have generally a good understanding of the recommendations for silage making provided by advisory services. However, few farmers apply the recommendation to seal the silo temporarily when the filling process is interrupted (e.g. overnight break or machinery failure). We believe this might be due to a prevailing uncertainty about the negative effects of delayed sealing. The objective of this study was to evaluate effects of delayed sealing on silage quality

Separating the effects of pre-ensiled chemical and microbial composition on silage fermentation and aerobic stability

Ensiling results of different forage types usually differ. For instance, legume silages usually contain more acetic acid, butyric acid and ammonia-N and are aerobically more stable than maize silages (Muck & O’Kiely, 1992; O’Kiely & Muck, 1992; Wilkinson & Davies, 2013). However, as to what extent these differences are related to chemical or microbial composition is yet unknown. In recent work by Mogodiniyai Kasmaei et al. (2015), a new ensiling methodology was introduced that enables sterilization of forages and inoculation with original microfloras. In the present experiment, we have further utilized this methodology to separate the confounding effects of microbial and chemical composition on silage fermentation and aerobic stability

The effect of nitrate content in forage on quality of silage fermentation

Nitrate content in fresh herbage is one of the factors affecting fermentation in silage. Hein (1970) observed that ensiling of forages with low nitrate content often results in silages with high butyric acid contents. Butyric acid is an undesirable product of clostridia in silages indicating low silage nutritional quality (Pahlow et al., 2003). The effect of nitrate on butyric acid formation is derived from its degradation products. Nitrate undergoes reduction to nitrite which can be further converted to nitric oxide which is considered to be toxic for clostridia (Spoelstra, 1983). Therefore, crops high in nitrate decreases clostridial activity and, hence, butyric acid formation. The effect of nitrate content in fresh crops on butyric acid formation was summarized by Weissbach (1996). The summary shows high occurrence (78%) of butyric acid in silages made from crops low (1 g NO3 per kg DM was only 26%. Since it is common to use silage additives to improve or secure a proper ensiling process, it is interesting to study how different nitrate contents in fresh crops influence efficiency of silage additives. The objective of the study was, therefore, to study the effect of nitrite containing silage additives on silage quality with crops differing in nitrate content

What can we learn from the past? Tracking sustainability indicators for the Swedish dairy sector over 30 years

CONTEXT: The dairy sector has undergone profound transformation over recent decades, resulting in considerably fewer but larger and more specialised farms, with unclear implications across sustainability dimensions.OBJECTIVE: The objective was to develop and employ a framework for assessing sustainability in the Swedish dairy sector to shed light on how recent historical developments (1990-2020) have influenced sustainability outcomes.METHODS: Using a data-driven, multidisciplinary approach, main areas of concern for sustainability in the primary production stages of the dairy sector were identified. These were then populated with indicators to track developments over time and highlight synergies and trade-offs.RESULTS AND CONCLUSIONS: Four areas of concern were identified and populated with eight indicators (listed in brackets): 'supporting ecosystems' (semi-natural grassland area, ley area, mean field size), 'climate impact' (methane from enteric fermentation), 'animal welfare' (veterinary treatments, percentage of culled cows due to diseases) and 'farm viability' (competitive wages, farmer age structure). The results showed that area of seminatural grassland per dairy cow decreased by 27% from 2003 to 2020. Area of ley per cow decreased slightly but the proportion of arable land on dairy farms devoted to ley cultivation increased, due to improved roughage quality enabling an increase in proportion of roughage in feed rations. In terms of climate impact, enteric methane emissions per kg milk decreased by 21%. Regarding animal welfare, veterinary treatments of diseases decreased from 45% to 21% over the 30 years, with declining trends for most recorded diseases except hoof disease. The indicators for farm viability showed that the average dairy farm was unable to pay a wage com-parable to the national average throughout most of the period 2004-2020, but a slightly positive trend was observed, although with large year-on-year variability. A rapid change in age structure was seen between 2003 and 2020, with the proportion of land managed by older farmers (+60 years) increasing from 12% to 22%, indicating challenges with demographic viability.SIGNIFICANCE: Tracking changes over time across sustainability dimensions gives important insights into improvements made and challenges that remain to be solved. Overall, developments in the Swedish dairy sector have diminished its capacity to support ecosystems, particularly related to semi-natural grasslands, while reducing its climate impacts and improving animal welfare. An increased specialisation has also resulted in spillover effects where services and impacts have shifted from dairy herds to specialised beef herds. These findings are important in navigating policy processes targeting developments in the dairy sector