Weather patterns in northern European regions have changed noticeably over the past several decades, featuring warmer, wetter weather with more extreme events. The climate is projected to continue on this trajectory for the foreseeable future, even under the most modest warming scenarios. Such changes will have a significant impact on livestock farming, both directly through effects on the animals themselves, and indirectly through changing exposure to pests and pathogens. Adaptation options aimed at taking advantage of new opportunities and/or minimising the risks of negative impacts will, in themselves, have implications for animal health and welfare. In this review, we consider the potential consequences of future intensification of animal production, challenges associated with indoor and outdoor rearing of animals and aspects of animal transportation as key examples. We investigate the direct and indirect effects of climate change on the epidemiology of important livestock pathogens, with a particular focus on parasitic infections, and the likely animal health consequences associated with selected adaptation options. Finally, we attempt to identify key gaps in our knowledge and suggest future research priorities.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/03BD4F335517DAC535C241C9AD1D3EA7/S175173111300075Xa.pdf/div-class-title-animal-health-aspects-of-adaptation-to-climate-change-beating-the-heat-and-parasites-in-a-warming-europe-div.pdf

Animal health aspects of adaptation to climate change: beating the heat and parasites in a warming Europe.

The aim of this work was to study the behavioural activities of two cow genotypes, Holstein-Friesian (HF) vs. Jersey · Holstein-Friesian (Jx), when managed within two production systems, a low inputs grazing (G) system vs. a high inputs confinement (C) system. Eighty spring calving cows (HF, n = 40 and Jx, n = 40), from AFBI Hillsborough (Northern Ireland) experimental dairy cattle, were randomly assigned to one of two production systems (G, n = 40 and C, n = 40) in a block design with a 2 · 2 factorial arrangement of four treatments (HF-G, HF-C, Jx-G and Jx-C). Cow behavioural activities (feeding, lying, standing and ruminating) were registered on three periods at 20-min intervals, between 16.00-22.00 h and 07.00-14.00 h. Average milk yields (kg cow ‐1 day ‐1 ) were higher (p < 0.001) in the C system (27.0) than in the G system (20.1), with differences (p < 0.001) between the two cow genotypes (HF, 25.1 vs. Jx, 22.0 kg cow ‐1 day ‐1 ). Milk production system showed an effect on cow behavioural activities. Animals on the G system spent more time (p < 0.001) grazing (522 min) than those on the C system spent feeding (173 min). Cows on the C system spent more time (p < 0.001) lying (C, 411 vs. G, 212 min), standing (C, 236 vs. G, 85 min) and ruminating (C, 244 vs. G, 141 min) than those on the G system. There were differences between periods for time spent lying (p < 0.001), feeding (p < 0.05) and ruminating (p < 0.001), while time spent standing did not differ between periods. Cow genotype had no effect on any of the behavioural activities.

https://dialnet.unirioja.es/descarga/articulo/4182445.pdf

Short communication. Behavioural activities of two dairy cow genotypes (Holstein-Friesian vs. Jersey x Holstein-Friesian) in two milk production systems (grazing vs. confinement)

Milk phospholipids: Organic milk and milk rich in conjugated linoleic acid compared with conventional milk

In pasture-based milk production systems, using available farm resources in order to reduce feeding costs, the composition and functional properties of dairy cows’ milk are of considerable importance to the dairy farmer, manufacturer and consumer. Basically, there are three options for altering the composition and/or functional properties of milk: 1) cow nutrition and grazing management, 2) cow genetics and 3) dairy manufacturing technologies. At the farm levels, manipulation of milk composition only occurs when it is perceived to be more profitable, normally, processing options are the option most considered. Nevertheless, opportunities exist for manipulation of milk composition on the farm to improve the human and physiological properties of milk and dairy products, such as enhanced concentrations of conjugated linoleic acid (CLA), or to improve its milk fatty acids (FA) composition for more efficient processing into a range of dairy products. This review considers the effect of dietary (pasture feeding, lipid feed supplements, seasonal and regional variations) and animal (breed, stage of lactation, parity and animal to animal) factors on milk FA composition of grazing dairy cows. Furthermore, it highlights the relevance that these factors, in the context of an integrative-view, might play on the sustainability of pasture-based milk production systems in humid areas in terms of milk differentiation and higher added value which profit would be directly reached for the milk producer on the farm.

http://ijas.iaurasht.ac.ir/article_513534_075ec844639a1accaf7fa43fe7b6e5fa.pdf

Effect of Dietary and Animal Factors on Milk Fatty Acids Composition of Grazing Dairy Cows: A Review

Incorporating a prediction of postgrazing herbage mass into a whole-farm model for pasture-based dairy systems

To maximize milk output and milk solids per hectare from grazing dairy cows it is necessary to identify the level of grazing swards in order to achieve high pasture dry matter intake (PDMI). The aim of this study was to investigate the effect of pre-grazing herbage mass (HM) and daily herbage allowance (DHA) on perennial ryegrass (Lolium perenne L.) swards structure, PDMI and milk performance. Sixty-four spring-calving Holstein-Friesian dairy cows were balanced and randomly assigned to one of four (n = 16) grazing groups (LL, LH, HL and HH) in a 2 × 2 factorial design. The treatments consisted on two pre-grazing HM, low (L- 1,600 kg DM ha ‐1 ) or high (H- 2,400 kg DM ha ‐1 ) and two DHA, low (L- 15 kg DM cow ‐1 day ‐1 ) or high (H- 20 kg DM cow ‐1 day ‐1 ). Swards structure, PDMI and milk performance were examined across the grazing season. The low HM groups completed 9.5 rotations of average 22 days length compared to 6.5 rotations of 32 days for the high HM groups. Herbage utilization was greater (p 4.0 cm) were lower (p < 0.001) for the low HM (221 and 170 kg ha ‐1 , respectively) than for the high HM (388 and 303 kg ha ‐1 , respectively). The high DHA had higher (p < 0.001) milk output (19.5 kg day ‐1 ) and milk solids (1.46 kg cow ‐1 ). The highest milk output per ha and per cow was achieved by LH, with low post-grazing residuals and high sward quality. Additional key words: grass intake; grazing management; herbage utilization; milk output per hectare; pasture allowance; spring-calving cows; sward quality.

https://dialnet.unirioja.es/descarga/articulo/3430721.pdf

Effect of pre-grazing herbage mass and daily herbage allowance on perennial ryegrass swards structure, pasture dry matter intake and milk performance of Holstein-Friesian dairy cows.

The aim of this study was to investigate the effect of different feeding proportions of forage ―grazing vs. silage― on milk fatty acids (FA) profile and conjugated linoleic acid (CLA) content of autumn calving Holstein-Friesian cows (n = 61) at CIAM (Galicia, NW Spain). Three treatments (S, 100% silage; G/S, 50% grazing + 50% silage; G, 100% grazing) were set and milk FA profile of dairy cows was determined by gas chromatography-mass spectrometry. The G group showed a decrease in short ( p < 0.05) and medium chain FA ( p < 0.001), with an increase in long chain FA ( p < 0.001) in comparison to the G/S and S groups, which showed the lowest levels ( p < 0.001) of mono- and polyunsaturated FA. The CLA content in milk fat increased ( p < 0.001) linearly in relation to the increased proportion of fresh grass in the diet of dairy cows from 0.49 and 0.82 to 1.14 g/100 g FA for the treatments S, G/S and G, respectively. During spring and summer, the levels of CLA were three times higher ( p < 0.001, +0.76 g/100 g FA) in milk from dairy cows at the G group than in cows at the S group and twice higher ( p < 0.001, +0.40 g/100 g FA) than in cows at the G/S group. High proportion of grass in the diet of cows increased CLA content, with the highest levels of unsaturated FA and the lowest levels of saturated FA, increasing the added value of milk on grazing systems using available farm resources.

Short communication. Effect of forage source (grazing vs. silage) on conjugated linoleic acid content in milk fat of Holstein-Friesian dairy cows from Galicia (NW Spain)

Milk performance of two cow breeds at two levels of supplementation in long residence time grazing paddocks.

Milk performance (protein and fat content) and milk fatty acids (FA) profile of dairy cows under supplementation with two sources of concentrate, oilseeds (C, cottonseed) at two levels, low (5kg DM/cow/day) and high (7 kg DM/cow/day), and cereal grains (B, barley) at high rate (7 kg DM/cow/day), were studied in three herds (n=36) of spring calving Holstein-Friesian dairy cows (200 days in milk). Animals were randomly assigned to one of three indoors (n=12) silage feeding regimes (C5, C7 and B7), using a TMR (total mixed ration) basal diet, containing 70-80% silage (grass: maize, 36: 64) and 30-20% concentrate. Daily milk yield (MY) was higher (P<0.001) at high level of supplementation (B7, 18.1andC7, 17.9 kg/cow/day, respectively) compared to low level (C5, 15.7 kg/cow/day), and dairy cows at the highest level of concentrate showed the highest (P<0.05) body weight (B7, 605 and C7, 598, respectively). Milk protein content was lower (P<0.05) in the high level of cottonseed (C7, 30.7 g/kg DM) than in the barley treatment (B7, 32.7 g/kg DM). There were no differences among treatments in milk fat and milk urea content.Weekly milk FA profile of cow milk was determined using gas chromatography-mass spectrometry,during seventy days in autumn, and no differences were found among treatments in short, medium and long chain FA. Despite this, higher (P<0.05) contents of polyunsaturated fatty acids (PUFA) and linoleic acid were found in the C7 treatment compared to the C5 treatment (2.48 and 2.22 vs. 2.16 and 1.92 g/100 g of FA methyl esters, respectively). Including the high levels of cottonseed and barley as a concentrate source for feeding dairy cattle revealed similar MY and milk fat content. However, the high level of cottonseed in the diet of dairy cows showed decreased milk protein content and increased linoleic acid and PUFA levels.

http://journals.iau.ir/article_514099_841b2d1c899e4acf8aacd2e05d1d6a36.pdf

A. González-Rodríguez

Papers

Effect of pre-grazing herbage mass and daily herbage allowance on perennial ryegrass swards structure, pasture dry matter intake and milk performance of Holstein-Friesian dairy cows.

Short communication. Effect of forage source (grazing vs. silage) on conjugated linoleic acid content in milk fat of Holstein-Friesian dairy cows from Galicia (NW Spain)

Milk performance of two cow breeds at two levels of supplementation in long residence time grazing paddocks.

Effects of concentrate source (cottonseed vs. barley) on milk performance and fatty acids profile of holstein-friesian dairy cows

Effect of Trifolium repens cultivars on yield and chemical composition of pasture sward.