The Research Column

In the studies, primary research papers were found through targeted Web of Science searches, the reference lists of recent reviews for each topic, and the reference lists of papers identified from these sources. Studies were included if they were published in English, the full text was accessible, and they compared treatments with and without contact between dairy cows and calves for a specified period. The resulting manuscripts underwent a 4-step appraisal process, and further manuscripts were sourced from reference lists.

A fermentation product of the yeast Saccharomyces cerevisiae (SC), has been widely used in diets of dairy cows with the aim of increasing production performance and stabilizing rumen pH. Several studies have reported positive effects such as increased DMI and milk production when cows were fed SC, but the results are inconclusive. Also,  the possible interaction between the fermentability of the basal diet and SC supplementation on DMI has not yet been addressed. Therefore, the objective of a study by Dr W.

South Africa is 13th on the list of highest emitters of global greenhouse gases GHG). Despite this is Africa still the smallest contributor to GHG emissions among the continents, yet the most vulnerable to the impacts of climate change. The effects will not be limited to rising temperatures and changing rainfall patterns, but also to increased severity and frequency of droughts, heat stress and floods. Agriculture is not only impacted upon by climate change but also contributes to global warming.

Bacteria are ubiquitous microorganisms present in all known environments, including various areas of the animal body as well as in fermented dairy foods, where they are organized in complex consortia. The microbial ecology of fresh cheese has been extensively investigated, and has lead to the generally accepted understanding that bacteria residing in milk may contribute beneficially to the aroma of fermented dairy products. Here, lactic acid bacteria are particularly important due to their positive or negative impacts on fresh and ripened cheese.

Dairy cattle often experience negative energy balance during the calving transition period, because of reduced feed intake and a drastic increase in nutrient demands after the onset of lactation, thereby contributing to high risk of metabolic disease and low immunity. This implies that feeding strategies during the calving transition period should be designed to maintain feed intake to mitigate excessive fat mobilization.

Some cheeses, including Camembert and related varieties, can be produced by different processes that vary in milk pre-acidification, cutting, curd handling and ripening.  Modification of these creates distinct cheeses such as lactic curd, stabilized curd and hybrids of the two. The objective of the study by Dr D. Batty and colleagues reported below, was to determine the influence of five Camembert-type cheese recipes on   composition and characteristics during ripening.

Due to perceived health reasons, consumers have shown an increasing interest in the consumption of cheese with a lower fat content. One of the main properties of reduced-fat cheeses is a higher protein to fat ratio that results in a more compact structure leading to a firmer and rubbery texture, a lack of flavour, bitterness (unacceptable sensory properties), development of off-flavours, poorer melting properties and a translucent appearance.

Reducing on-farm storage and retail waste should increase agricultural resource efficiency and, thus, food availability. One way of reducing waste and increase efficiency could be to reduce inclusion of human-edible products such as cereal grain (e.g. maize, wheat, oats etc) and soybean meal in the diets fed to dairy cows in intensive production systems.

Consumers complain about spoilage due to bacterial growth and spoilage also contributes to dairy product waste, which in a developing country we cannot really afford. We probably do not have figures in South Africa, but milk spoilage in the US amounts to $6.4 billion per year. Microbial spoilage is of particular concern and can be caused by either psychrotolerant spore formers, which likely originate from raw milk, or by post-pasteurization contamination (PPC).

Increasing input costs and new regulations to reduce nutrient loss have created pressures to improve agricultural nutrient use efficiency. In ruminants, and therefore dairy cattle, the greatest potential to reduce greenhouse gas (GHG) emissions and other environmental pollutants involves improving animal and herd efficiency.