bluuebunny/crossref_metadata_2025 huggingface dataset:
A comparison of the availability of copper in copper: lysine and cupric sulphate for sheep
Authors: Suttle N F , Brebner J
Published: November 2021

Chelated trace elements are increasingly used to supplement livestock feeds despite little evidence that they have a higher nutritive value than simpler and cheaper inorganic salts. Advantages for chelated sources should be most evident for elements such as copper (Cu) in the diet of ruminants which rarely absorb more than 10% of the Cu they ingest because of antagonisms with sulphur and molybdenum initiated in the rumen.

A copper:lysine complex (CuPLEX, 100; ZinPro Animal Health Ltd) was, therefore, compared with cupric sulphate (CuSO4.5H2O) for ability to increase liver Cu stores in sheep. Five groups of five Suffolk cross sheep, 10 months old and weighing 44kg on average, received 4.0kg DM daily of a basal diet of (kg/l00kg) whole oats (90.8), urea (1.8), calcium sulphate (1.4), sodium bicarbonate (1.8), and potassium chloride (0.5), with trace elements and vitamins A, D and E coated onto the grain in a sugar solution. A control group received the unsupplemented diet containing 3.5mg Cu/kg DM while four groups received Cu:lysine or CUSO4 added at a lower (1) and a higher (2) level, giving diets containing 9.8 and 14.6 or 8.4 and 13.2mg Cu/kg DM, respectively.
The reactions of farmed red deer to transport: effects of road type and journey time
Authors: Grigor P.N. , Goddard P.J. , Littlewood C.A. , Macdonald A.J.
Published: November 2021

Both road type and journey time may influence the welfare of animals during road transportation. Animals may face a higher risk of injury on narrow, winding roads (Waran et al., 1993), and increasing the journey time may have deleterious consequences for animal welfare (Mormede et al., 1982), carcass bruising (Yeh et al., 1978), and meat quality (Wythes et al., 1981). In this study, the effects of road type and journey time on the behavioural and physiological responses of farmed red deer were investigated.
The behavioural priorities of mink (Mustela vison) in a closed economy
Authors: Cooper J. J. , Mason G. J.
Published: November 2021

Consumer demand theory has been used to assess the environmental requirements of domestic animals, because they will defend consumption of important resources, but not consumption of less important resources as their cost is increased (Dawkins, 1983). A commonly used approach is to place the cost on access to the resource, where once the animal has overcome the cost of access, there is no limit on time spent with a resource. So animals can compensate for fewer visits by spending longer with the resource on each visit (Sherwin and Nicol, 1995, Cooper and Mason, in press), in which case price paid and amount consumed may not covary, which would contravene the assumptions underlying the construction of demand functions (Mason et al., in press). In this experiment we investigated one solution to this problem: increasing the entry fee until the subject ceases to gain access to each resource.
The use of pedigree estimates of genetic merit to predict progeny performance of Holstein Friesian bulls tested in the UK
Authors: McGuirk B.J. , Smith J. , Mrode R.
Published: November 2021

Over the past 10 years, dairy breeding in the United Kingdom has switched from British Friesian to the North American type Holstein. Many of the bulls entering progeny testing in the UK in that period were sourced from overseas bull mothers, especially from the US. The aim of this study was to compare current predictions of the genetic merit of those bulls, using pedigree information, with the performance of their UK daughters.
Genotype with nutrition interaction for performance test traits in pigs selected for lean growth rate
Authors: Cameron N.D. , MacLeod M.G.
Published: November 2021

Information on the sensitivity of genotypes to different nutritional inputs is important to the pig industry to ensure the feeding of appropriate diets. Testing genotypes on a single diet may constrain potential growth, defined by an animal's genotype, by under-supplying nutrients or may reduce the efficiency of nutrient utilisation by over-supplying nutrients. The current study examined the relationship between selection strategy and the sensitivity of genotypes to different nutritional inputs.
Will treatment with progesterone, either alone or with oestradiol result in behavioural oestrus and a normal length luteal phase in postpartum beef suckler cows induced to ovulate by calf isolation and once-a-day suckling?
Authors: Mackey D.R. , Diskin M.G. , Sreenan J.M. , Roche J.F.
Published: November 2021

In beef suckler cows, the prolonged interval from calving to first ovulation (post-partum interval, PPI) is due to failure of ovulation of dominant follicles. It appears that a combination of poor body condition, maternal calf-bond and suckling act to suppress the LH pulse frequency necessary for ovulation. A combination of calf isolation and once-a-day suckling can significantly shorten the PPI, but the first ovulation generally occurs without overt oestrus and the subsequent cycle is short (8 to 11 days) due to lack of progesterone priming. The aim of this study was to examine the effects of progesterone or progesterone and oestradiol in conjunction with calf isolation on the interval to first ovulation, incidence of overt oestrus at first ovulation and length of the subsequent interovulatory interval.
The responses of high genetic merit dairy cows to changes in silage quality and level of supplementary concentrate
Authors: Ferris C. P. , Gordon F.J. , Patterson D.C. , Mayne C.S. , McCoy M.
Published: November 2021

Supporting the higher milk yields of high genetic merit cows requires an increased supply of nutrients to the animal. In grass silage based production systems this is achieved by either offering additional concentrates or by improving the quality of the silage. However, the relationship between silage quality and the response to concentrate supplementation has not been defined for high merit animals. It might be expected that as level of concentrate supplementation increases, the quality of the silage offered will become less important. This study was undertaken to define the responses of high merit dairy cows to a range of concentrate levels given in addition to two contrasting silage types.
Effect of ad libitum access to milk replacer to piglets on performance of piglets, slaughter pigs and sows
Authors: Lindberg Jan Erik , Neil Maria , Cidh Mari-Ann
Published: November 2021

One way of improving the growth rate of piglets could be to provide a palatable diet with high nutritive value (Pluske et al., 1995). Several earlier studies have shown that this is possible by improving the piglet diet either by selecting ingredients or by processing the cereals in the diet (Hardy, 1992). An alternative could be to offer the piglets a milk replacer, in addition to a dry piglet feed, in order to make the transition to a complete dry feeding smoother. Recent data suggest that villus height and crypt depth are maintained after weaning in piglets when fed cows whole milk and that the capacity to absorb monosaccharides was increased (Pluske et al., 1996). The aim of the experiment was to study the effect of ad libitum access to milk replacer to piglets, in addition to dry piglet feed and sows milk, on the performance of piglets, slaughter pigs and sows.
Relation between in vivo and in vitro fermentation of oligosaccharides in weaner pigs
Authors: Houdijk J.G.M. , Williams B.A. , Tamminga S. , Verstegen M.W.A.
Published: November 2021

Non-digestible oligosaccharides (NDOs), including fructo-oligosaccharides (FOS) and trans-galacto-oligosaccharides (TOS), are not digested by endogenous enzymes, but may be fermented by bacteria such as lactobacilli and bifidobacteria (Tomomatsu, 1994). Thus, dietary NDOs may alter fermentation characteristics of the microflora of the host. In this experiment, in vivo and in vitro fermentation characteristics of NDOs in weaner pigs were studied, using the cumulative gas production technique (Theodorou et al.,1994).

A NDO-free control diet (CON), with oatshuskmeal (OHM) as a fibre source, and this diet with 40 g FOS (FOS40) or TOS (TOS40) per kg (w/w against cellulose) was restrictedly fed for 7 weeks (2.6*Em) to 3 groups of four 35-day old individually housed weaner pigs. Total faeces were collected from day 13-18 to determine crude fibre digestibility. Pigs were fitted with a PVTC-cannula on day 21 (Van Leeuwen et al, 1991). Inocula for gas production were anaerobically prepared from faeces (day 14-16) and ileal chyme (day 33-35, via PVTC-cannula). Samples were diluted (1:4) with sterile saline and filtered through cheese cloth. Five ml filtrate were injected into airtight bottles, containing 80 ml growth medium and no substrate (BLA) or 0.25 g FOS, TOS or OHM as sole energy source.
A comparison in growth performance of young pigs fed six different cultivars of wheat
Authors: Pearce A.N. , Rose S.P. , Kettlewell P.S. , Schulze H.
Published: November 2021

Wheat is a major source of energy and may account for over 50% of the pig's diet. Although there are differences in the energy and protein content of different cultivars of wheat, these factors have not been correlated with differences in the growth of pigs (Bell and Anderson 1984). The objectives of this trial were to compare the growth performance of young pigs offered diets differing only in the cultivar of wheat used and to establish whether variation in growth could be explained by other chemical or physical properties of the wheat.

72 crossbred (Large White x Landrace x Large White) pigs were selected at weaning at a mean age of 24 days and mean weight of 7.86 kg. They were allocated by weight in pairs in a randomized block design to one of six dietary treatments in 6 replicates and over three time periods.
An evaluation of wheat specific weight as a determinant of nutritive value for pigs and poultry
Authors: Stewart A. H. , Acamovic T. , Taylor A. G. , Fraser H.
Published: November 2021

The north east of Scotland has seen poor harvest seasons in five out of the last ten years. The 1995 season was predicted to be one of the highest yields for a number of years, however, 14 days of continuous rain at harvest resulted in a high proportion of poor quality, sprouted and shrivelled grains, which, if not properly dried, were of dubious micro-biological status. The price of feed wheat is usually determined by the specific weight if it falls below the minimum standard of 72 kg/hl, however, de Lange et al (1993) expressed concern that bushel weight was not a good indicator of DE content. The objective of this experiment was to determine how the commercial assessment of such grains linked to feed value in poultry and the performance of pigs.
The effect of the source of dietary supplemental zinc on tissue copper concentrations in the rat
Authors: Lowe J.A. , Wiseman J
Published: November 2021

Hill and Matrone (1970) postulated that chemically similar minerals would manifest biological similarity. As a result there would be competitive antagonism for inclusion in metabolic processes, including intestinal transport. Such interactions have been reported for copper (Cu) and zinc (Zn), where the chronic over supply of Zn reduced Cu absorption (Fischer, Giroux and L'Abbe 1981). Previous work ( Lowe, Wiseman and Cole 1994) has indicated that when Zn is supplied as a chelate that antagonism to its absorption from calcium may be overcome. As many diets, specifically for piglets, now appear to contain very high levels of supplementary Zn it is appropriate to evaluate the effects of its dietary supplemental source on other mineral uptake.

24 adult female CD rats (327g, SE 4.7) were randomly divided into four groups and fed a maintenance diet (27.mg. kg-1 Cu) on a free choice basis containing 28mgZn.kg-1 to which 65mg of supplemental Zn.kg-1 from four different sources was added for the duration of the study.
Fatty Acid Profile and α-Tocopherol Content of Porcine Muscle During Oxidative Changes
Authors: Onibi G.E. , Scaife J.R. , Murray I.
Published: November 2021

Polyunsaturated fatty acids (PUFA) especially n-3 PUFA are important components of healthy human diets but these fatty acids are very susceptible to oxidation. Lipid peroxidation has been implicated as contributor to many pathological processes in humans (Byers, 1993). It is well established that tissue vitamin E (α-tocopherol; AT) protects lipid against peroxidation in vivo and in vitro. During lipid oxidation, vitamin E supplies are depleted and there are health benefits from higher intakes of the vitamin. In this study, changes in fatty acid composition and AT content of pig muscle during-oxidation were examined.

Twenty four Large White x Landrace pigs were individually fed, from 50 to 90 kg LW, either a control (CD) diet (containing palm oil) or a diet based on full-fat rapeseed (FFR; 250 g/kg) (diet FRD) with varying levels of α-tocopheryl acetate (ATA) (0, 200 and 500 mg/kg diet for FRD0, FRD200 and FRD500 respectively). Diets were isonitrogenous and isocaloric.
Relationships between taste panel assessment and meat quality in pigs
Authors: Bampton P.R.
Published: November 2021

Eating quality of fresh pork is important to consumers and processors. To assess the effect of genetic selection and breed substitution it is necessary to examine the relationships between eating quality and performance and carcass traits.
Reproductive performance and aggression between sows re-mixed into small stable groups at different stages during the embryo implantation period following initial mixing at weaning
Authors: Burfoot A. , Kay R.M. , Corning S.
Published: November 2021

With the advent of the stall and tether ban in the UK it is now a requirement to house dry sows in groups throughout their pregnancy which necessitates their being mixed with other sows at some point after service. It is generally recommended that mixing sows during the embryo implantation period should be avoided as this is thought to effect embryo survival rates. The object of this experiment was to demonstrate the aggression that occurs between sows after mixing and determine the effect on reproductive performance when mixing sows at different times during the 42 days post-service.

294 sows were mixed at six different times during early pregnancy: 0 to 7(T1), 8 to 14,(T2) 15 to 21(T3), 22 to 28(T4), 29 to 35(T5) and 36 to 42(T6) days post service. Six groups of sows from six consecutive weeks weanings were served at the first post-weaning oestrus and kept in stable weekly treatment groups until the sixth group was served.
The effects on neonatal piglet behaviour and tissue composition of feeding sows a diet containing a high level of docosahexaenoic acid (DHA) in late gestation and lactation
Authors: Bland I. M. , Rooke J. A. , English P. , Edwards A. , Noble R. C.
Published: November 2021

Neonatal mortality is a major source of economic loss to the pig industry. Polyunsaturated fatty acids (PUFAs), especially DHA, have been implicated in brain development in man and other species and a pre-natal supply of PUFAs may have a role in influencing post-natal survival. The purpose of this study was to investigate the effect of feeding increased amounts of DHA during gestation and early lactation, on piglet viability and tissue composition.
Digestibility, nitrogen retention and plasma metabolite concentrations in steers offered whole crop wheat silage-based rations
Authors: Moloney A.P. , O'Kiely P.
Published: November 2021

The yield of dry matter (DM) in a mature wheat crop can equal that obtained from three cuts of grass. Ensiled mature whole crop wheat is however characterised by a lower digestibility and lower crude protein concentration than good quality grass silage. Addition of urea at ensiling has been shown to increase the digestibility and the non-protein nitrogen concentration of whole crop wheat silage. The objectives of this study were to determine (i) the effect of urea-treatment on the in vivo digestibility of wheat of relatively high moisture concentration and (ii) the effects of the provision of a rapidly fermentable carbohydrate supplement on nitrogen metabolism in steers fed these silages.
Nutritional evaluation of poultry litter treated with acids incorporated in sheep diet
Authors: Osman A. A. , Ap Dewi I. , Swidan F. Z. , Omed H. M.
Published: November 2021

Poultry litter is an economical and safe source of crude protein, minerals and energy for ruminant animals. The aim of this study was to test diets containing poultry litter treated with acids as a component of rations for growing lambs.

Four diets were used in this study, a control diet, diet mix containing untreated poultry litter, diet mix containing poultry litter treated with HCl acid and diet mix containing poultry litter treated with acetic acid. The control diet consisted of 48% maize, 40% wheat bran, 10% sun flower seed cake, 1.5% limestone and 0.5% salt. In the other three diets the sun flower seed cake was replaced untreated poultry litter, poultry litter treated with HC1 and poultry litter treated with acetic acid respectively. The diets were manufactured in a commercial feed mill. All ingredients were ground to a maximum size of 6 mm. In the press unit steam was used for pelleting the feed into 8 mm diameter pellets.
A study of the effect of housing system and milk yield level on the performance and behaviour of dairy cattle
Authors: Fregonesi J.A. , Leaver J.D.
Published: November 2021

Housing system and milk yield level are considered important factors which relate to health and welfare problems of dairy cows ( Webster,1995). The increasing genetic merit of dairy cows could mean that the existing housing systems are inadequate for the welfare of such cattle. The aim of the experiment was to study the effects of housing system (strawyard and cubicle) and milk yield level (low and high) on the performance and behaviour of dairy cattle.
Behavioural strategies of dairy cows grazing swards of different surface heights
Authors: Gibb M.J. , Huckle C.A. , Nuthall R. , Rook A.J.
Published: November 2021

Sward surface height (SSH) has a significant effect on bite mass in dairy cows grazing continuously stocked pastures (Gibb et al., 1995). To compensate for this, cows must either attempt to maintain intake rate by increasing bite rate, or increase the total time spent eating. Previous work (Gibb et al., 1995) showed that lactating cows had limited capacity to increase bite rate, but this work was not designed to examine whether animals altered bite mass or bite rate in response to different nutritional demands. An experiment was therefore conducted to compare the grazing behaviour of cows with high or low intake potential, over a range of SSH on continuously stocked swards.
Effect of reduced nitrogen fertilizer in pasture on milk quality : results of 4 years
Authors: Raskin P. , Dufrasne I. , Minet V. , Mayombo A.P. , Istasse L.
Published: November 2021

Since CAP reform and environmental problems, there is, in agriculture, a tendency to reduce the production. Reduction of nitrogen fertilizer was suggested to decrease intensification. Nowadays, high quality milk has to be produced for the dairy industry, in order to be processed as cheese, butter,... Another aspect in milk production is the payment based on the composition (Beguin, 1994). The aim of this experiment was to study the effects of a reduction in nitrogen fertilizer on milk yield, butterfat, protein, urea and cells contents. The trial was repeated over four years consecutively.
Changes in dam characteristics of Holstein Friesian (HF) cows selected for Embryo Transfer in the United Kingdom (UK)
Authors: Winters M S , Coffey M P
Published: November 2021

The use of Embryo Transfer (ET) in HF cattle breeding is now a routine technique. It provides an opportunity to increase the contribution of the dam to genetic progress in the population. The aim of this paper is to characterise the cows chosen as embryo donors, and to detect any changes in donor characteristics.
A preliminary survey of the trace element status of Llamas (Lama glama) in the UK
Authors: Illingworth D.V. , Jackson D. , Mackenzie A.M. , Telfer S.B.
Published: November 2021

The commercial rearing of llamas in the UK is of increasing interest but there is little information on their trace element status especially regarding copper metabolism. Previous work on a closely related species, the Alpaca (Lama pacos) has shown them to utilise copper less efficiently than sheep (Grace et al., 1994). As llamas are grazed on marginal or improved pastures they may become susceptible to copper deficiency (thiomolybdate toxicity). However, evidence also shows that llamas can suffer from copper toxicity (Junge and Thornburg, 1989). Therefore diagnosis of trace element status is needed prior to nutritional supplementation.
Dietary availability of magnesium hydroxide powder in sheep and in vivo and in vitro assessments of granular calcined magnesites of different origin
Authors: Hemingway R.G. , Parker E.R. , Ritchie N.S.
Published: November 2021

The standard recommendation for grazing cows to be given 60g calcined magnesite (c. 30 g Mg /day) seems large relative to the ARC (1980) dietary Mg allowance (0.17 coefficient of Mg absorption in the whole diet) of 32.6 g for 30 kg/day milk yield. ARC (1980) estimated the coefficient of absorption of calcined magnesite could be 0.05-0.10 and indicated that supplementary magnesium sources should be readily soluble in rumen liquor. Both temperature of calcination and particle size markedly influence rumen solubility and apparent Mg availability of calcined magnesite (Adam et al. 1996). Magnesium hydroxide powder (H, 404 g Mg/kg) is very finely divided (970 g/kg < 20 μm of which 870 g/kg is < 6um and with 200 g/kg < l μm diameter and is manufactured on a large scale (Redland Minerals, Hartlepool TS24 0BY). ‘Granular’ calcined magnesites are screened to < c. 2000μm diam.
Effect of dietary Molybdenum content and floor type on the liver copper concentration at slaughter and Iamb growth rate of early weaned lambs
Authors: O'Hara M. , O'Doherty J.V. , Quinn P. J. , Callan J.J. , Crosby T. F.
Published: November 2021

The accumulation of copper (Cu) in the liver of intensively fed sheep, resulting in sub-clinical organ damage and eventually death due to Cu poisoning, is an important constraint on intensive animal production. Previous studies have demonstrated the antagonistic effect of dietary molybdenum (Mo) on Cu absorption in the ruminant (Suttle, 1991). The role of rumen ciliate protozoa in the breakdown of soluble protein and liberation of sulphide, also a Cu antagonist, and the reporting of a number of cases of chronic Cu poisoning in defaunated animals suggests that the state of the rumen microbial population may also have an effect on the absorption of dietary Cu. The aim of this experiment was to assess the effect of adding Mo to the diet and the availability of straw bedding, (through its effect on rumen environment and microbial population), on the liver Cu concentration at slaughter of early weaned lambs finished intensively on an all concentrate diet.
The effects of supplementary sodium on the magnesium status and behaviour of dairy cows fed silage and concentrates
Authors: Arney D.R. , Phillips C.J.C. , Kaert O.
Published: November 2021

Recent research has demonstrated that supplementary sodium enhances the magnesium status of cattle fed fresh herbage by limiting the antagonism of potassium to magnesium absorption in the rumen (Chiy and Phillips, 1993). This may explain the observed reduction in the somatic cell concentration in the milk of grazing dairy cows when they are offered a sodium supplement (Phillips et al. 1996). Magnesium has been recognised as the main macroelement affecting immunocompetence in laboratory animals (Miller, 1985), and it is likely that it is important for grazing ruminants, which are prone to hypermagnesaemia. It is unclear whether sodium supplements would be beneficial to cattle fed conserved feeds, where hypomagnesaemia is less common.
Effect of protected methionine supplementation of the diet on the partitioning of dietary nitrogen in the Angora goat
Authors: Souri M. , Galbraith H. , Scaife J.R.
Published: November 2021

Angora goats are efficient producers of hair fibre. They produce more fibre in relation to their size than sheep(Shelton et al., 1973). In skin and Mohair fibre cystine, which may be synthesised from methionine, is present in relative excess (5-10 times) to the other amino acids, when compared with major protein stores, such as skeletal muscle. Consequently a limitation in the supply of sulphur amino acids, may have disproportionate effects on the amount of nitrogen partitioned to other body tissues. The objective of this study was to investigate the effect of additional rumen protected intestinally available methionine in the diet on the partitioning of nitrogen between mohair and other body tissues in the Angora goat.
Estimation of direct and maternal genetic parameters for 12 week weight for Welsh Mountain sheep
Authors: Aslaminejad A.A. , Roden J.A.
Published: November 2021

The dam's milk production, mothering ability and the lamb's own genetic potential are important for preweaning growth. If there are strong maternal effects, which have not been separately accounted for, they can bias the estimates of heritability.

The objective of this study was to estimate genetic parameters for 12 week weights in Welsh Mountain lambs, and to assess the relative importance of the maternal genetic effect in this trait.
The identification and treatment of aberrant luteal activity during anoestrus in Suffolk ewes submitted for artificial insemination
Authors: McKelvey W A C , Robinson J J , Gebbie F E , Lindsay E , Dingwall W S
Published: November 2021

The success of sheep breeding programmes involving sire reference schemes depends on effective oestrous synchronisation programmes that provide optimum pregnancy rates following fixed-time insemination (McKelvey & Simm, 1995). Effective oestrous synchronisation is characterised by low progesterone concentrations at the time of insemination. However in pedigree Suffolk ewes inseminated at a synchronised oestrus in early August, Dingwall et al (1995) reported that a significant number of ewes in some flocks had elevated progesterone concentrations at the time of insemination and, as a consequence, flock fertility was adversely affected. It is hypothesised that high progesterone reflects aberrant luteal activity arising from spontaneous ovulations following the preceding lambing. The present study sought to identify the incidence of aberrant luteal activity in Suffolk ewes during seasonal anoestrus and to study the effect on conception of interventional treatment of these animals prior to artificial insemination.
A comparison between tris and milk diluents for liquid storage of ram semen in Iran
Authors: Ahangari YJ
Published: November 2021

The use of semi-skimmed cow milk diluent for liquid storage of ram semen is more convenient in Iranian sheep farming condition than other solutions. Preliminary tests showed that the motility and live percentages of ram spermatozoa were significantly (P>0.05) lower for semen samples were diluted in citrate buffer than semen samples in either tris buffer or semi-skimmed cow milk (Ahangari, 1996). This study was carried out for liquid storage of ram semen under Iranian farm conditions.
Effects of Yucca shidigera extract on ammonium, pH and short chain fatty acids during the in vitro anaerobic fermentation of hay by ruminal fluid obtained from sheep
Authors: Ryan J.P. , Quinn T. , Leek B.F.
Published: November 2021

It has been suggested that the beneficial effects of yucca plant (Yucca shidigera) extract when used as a feed additive are based on its demonstrated ability to bind ammonium (Cromwell, et al., 1985; Johnston, et al., 1981). Benefits include the reduction of noxious gasses, the easing of waste management problems and the enhancement of livestock performance. However the amount of ammonium bound is very small (Ryan, et al., 1993; Quinn and Leek, 1994), and it is difficult to explain the observed enhancement of livestock performance, particularly in ruminants, in terms of this effect alone. Consequendy, in order to evaluate the overall effect of Y. shidigera extract on rumen fermentation in this study, samples of ruminal fluid from pre-conditioned hay-fed sheep were incubated with the extract and die effects on ammonium, pH and short chain fatty acids after 24 h were compared.
The prediction of in vivo digestibility by laboratory techniques
Authors: Mc Entee Conor , O'Mara F. P. , Caffrey P. J. , Reilly P. , Cunningham D. , Rath M.
Published: November 2021

The in vivo digestibility of compound foodstuffs and ingredients can be predicted from laboratory techniques such as the in vitro rumen fluid (RF), the pepsin cellulase gammanase (PCG) and the neutral cellulase gammanase (NCG). There have been few comparative studies of these techniques using concentrate feed ingredients, especially since the addition of gammanase to the cellulase based techniques. Young et al. (1996) reported little difference between the cellulase based techniques in the accuracy of predicting in vivo organic matter digestibility (OMD) of concentrate ingredients, but both were superior to the rumen fluid technique. The objective of this study was to evaluate these techniques with a different set of foodstuffs which included less cereal and pulp samples but more maize by-products and oilseed meals.
The potential of near infrared reflectance spectroscopy (NIRS) to evaluate digestibility and degradability parameters of undried silage
Authors: Park R.S. , Agnew R.E. , Gordon F.J. , Steen R.W.J.
Published: November 2021

NIRS has proved to be a rapid, accurate method of evaluating grass silage quality parameters using dried, milled samples. Recent research by Park et al., (1996) has shown that undried silage can be used to accurately estimate a wide range of chemical and biological parameters. The digestibility and degradability fractions of silage are important indicators of silage nutritive value. This study was undertaken to further explore the potential of NIRS as a means of predicting a range of digestibility and degradability components of undried grass silage.
A comparison of four solvents for determining the proportion of soluble dry matter in fresh grass and grass silage
Authors: Deaville E. R. , Komwihangilo D. , Givens D. I.
Published: November 2021

Most protein systems include an estimation of the proportion of protein (nitrogen x 6.25) which is immediately soluble in the rumen. However, since the procedures employed generally involve mechanically washing samples in cold water the validity of these values have been questioned. The aim of the present experiment was to compare different solvents with rumen liquor for determining the proportion of soluble dry matter (DM) in grass and grass silage.
Leucine metabolism across the gastrointestinal tract of sheep infected with Trichostrongylus colubriformis
Authors: Yu Feng , Bruce L.A. , Coop R.L. , MacRae J.C.
Published: November 2021

In previous studies where sheep were subjected to experimental subclinical Trichostrongylus colubriformis infections, protein metabolism was seriously impaired during both the initial infection (5-7 weeks at early dosing) and the subsequent immune response (11-13 weeks of dosing) periods (see MacRae, 1993). Symonds and Jones (1983) reported that T. colubriformis infection increased the rates of protein synthesis in the small and large intestines of guinea pigs by 24 and 70% respectively, however there are no equivalent data in farm animals. In the present study trans-organ catheterisation procedures have been coupled with mass isotope tracer kinetics to examine leucine metabolism across the gastrointestinal (g.i.) tract of lambs subjected to subclinical T. colubriformis infection.
Physiological characteristics of high genetic merit and low genetic merit dairy cows: a comparison
Authors: Sorensen A. , Alamer M. , Knight C. H.
Published: November 2021

Genetic selection has greatly improved individual cow productivity. A high genetic merit Holstein Friesian cow will produce 10,000 of litres of milk in a 305 day lactation, those of lower genetic merit half this amount. Despite major research effort in generating these differences, quantitative biological description of what has been achieved is lacking. The aim of this study was to compare biological variables of relevance to milk synthesis in well defined high genetic merit and lower genetic merit dairy cows.

12 cows of high genetic merit (HGM: top 5% of UK national herd) and 12 of lower genetic merit (LGM: close to UK average) were purchased from the Blythbank and Langhill herds; the ontogeny of these selection lines has been described elsewhere (Woolliams et al, 1993). Mean parity was 3.7±0.3 and was balanced between HGM and LGM. Management of the two groups was identical. Measurements were made over a period of two weeks close to peak lactation. Milk yield was recorded at each milking. Plasma samples were collected and analysed for a variety of hormones by radioimmunoassay and metabolites by established spectrophotometric assays. Udder size was determined by a casting technique (Dewhurst et al., 1993) and mammary biopsies for key enzyme activities were obtained as described by Knight et. al. (1992). Differences between lines were analysed by analysis of variance (ANOVA).
Predicted responses to selection from indices including feeding pattern traits of pigs as selection criteria.
Authors: Hall A.D. , Hill W.G. , Bampton P.R. , Webb A.J.
Published: November 2021

The introduction of electronic feeders has allowed accurate measures of individual feed intake in a group housing system, similar to that in the production environment. These feeders also provide other feeding pattern information, such as how many meals are taken each day and how big they are, which could be of use to further improve the accuracy of selection for feed conversion ratio and growth traits. The main aims of this study were to predict the increase in genetic gain achieved by including feed intake and feeding pattern traits as selection criteria.
The influence of parity on lactation curve coefficients in dairy cows
Authors: Friggens N. C. , Emmans G. C. , Veerkamp R. F.
Published: November 2021

There are marked differences between heifers, 2nd parity and older cows in their lactation curves, even when they are offered high quality rations ad libitum. These differences indicate different energy requirements, and thus should be taken into account when formulating rations for the different parities. The objective of this study was to quantify how the pattern of milk production relative to time from calving is affected by parity for incorporation into energy requirement predictions.
A simulation of the effects of changes in the Na and K content of milk during mastitis on the growth of Staphylococcus aureus, Streptococcus uberis and Escherichia coli
Authors: Arney D.R. , Lindsay H.J. , Bogoro S. , Phillips C.J.C.
Published: November 2021

In a mastitic event damage to the epithelial tissue of the mammary gland, and in particular an increase in paracellular permeability allows sodium to enter the milk from the blood (Schaar and Funke, 1986). Normally there is a stepwise gradient of declining sodium concentration from the interstitial fluid to the epithelial cells to the milk (Berga and Neville, 1985). Milk potassium content is reduced in milk of cows with mastitis, but the proportional change is less than that of sodium (Wegner and Stull, 1978). An experiment was conducted to investigate the response of three mastitis pathogens to the changes in sodium and potassium concentrations in their growth media that are typical of the changes occurring during a mastitic event.
Differences in the calpain enzyme system in tough and tender samples of porcine longissimus dorsi
Authors: Sensky P.L. , Parr T. , Scothern G.P. , Perry A. , Bardsley R.G. , Buttery P.J. , Wood J.D. , Warkup C. C.
Published: November 2021

The calpain enzyme system plays an important role in the proteolytic events leading to the conversion of muscle to meat in livestock species. Evidence in beef has shown that the levels of calpastatin, the inhibitory component of the system, measured 24 h after slaughter can be used to predict the degree of tenderisation achieved at the end of the normal conditioning period (Koohmaraieet al., 1995). Recent experimental work in pig muscle has shown that calpastatin can be increased by protocols which mimic stress and that these increases relate to changes in tenderness (Senskyet al., 1996; Senskyet al., 1997). In this study differences in the calpain system in randomly selected pigs slaughtered at a commercial slaughterhouse were investigated, with respect to the degree to which the meat tenderised.
The ability of different feed evaluation systems to predict rumen microbial nitrogen flow of lactating dairy cows
Authors: Stefanon B. , Gruber L. , Moscardini S. , Volpe V. , Susmel P.
Published: November 2021

The contribution of rumen microorganisms to the protein absorbed in the intestine is a key factor to evaluate diets for ruminants, and the urinary excretion of purine derivatives (PD) has recently been proposed to estimate rumen microbial protein synthesis in cows (Verbic et al., 1990). This study refers to the relationship between PD excretion and the microbial nitrogen estimated according to recent protein systems for ruminants.
Selection of diets differing in sulphur content by sheep in sulphur adequate or depleted states
Authors: Hills J. , Nolan J.V. , Hinch G.N. , Lynch J.J.
Published: November 2021

Recent studies have shown that when offered a choice of feeds with different concentrations of a particular nutrient (crude protein), sheep can select a diet that meets their current requirements (Kyriazakis and Oldham 1993). To further examine this diet selection behaviour a choice of foods differing in the concentration of S was offered to sheep that were either in a sulphur (S) adequate or a S depleted state. Study of S selection was considered to be the next logical step after protein because of its role in the synthesis of proteins by the rumen micro-organisms.
Effect of feeding a high energy/low protein diet to finishing pigs on growth and meat quality
Authors: Blanchard P.J. , Mantle D. , Chadwick J.P. , Willis M.
Published: November 2021

Previous work (Blanchard et al, 1995) has suggested that the feeding of a high energy/low protein diet to finishing pigs produces pork of a superior eating quality compared to animals fed conventional energy and protein diets. It has been demonstrated in recent studies (Blanchard et al, 1995) that pork eating quality, particularly tenderness, can be influenced by a change of diet imposed at two weeks prior to slaughter. It has also been suggested (Warkup and Kempster, 1991) that both growth rate and fatness are positively correlated to pork eating quality and that proteolytic enzymes are involved in determining eating quality (Blanchard 1994). The objective of this study was therefore to test these various hypothesis.

Two diets were evaluated: CEP diet (DE 14.0 MJ/kg, Protein 200 g/kg, Lysine 10.0 g/kg) and HELP diet (DE 15.0 MJ/kg, Protein 160 g/kg, Lysine 7.0 g/kg). Treatment 1 animals (n=26) received CEP fed ad libitum 45 kg to 90 kg Iwt. Treatment 2 animals (n=23) received HELP fed ad libitum 45 kg to 90 kg lwt. Treatment 3 animals (n=23) received CEP diet until 14 days prior to slaughter following which they received HELP diet fed ad libitum. A range of carcass and meat quality characteristics were recorded. Grilled loin steaks from each animal were evaluated for eating quality characteristics by trained sensory panel and rated on a scale of 1-8 (increasing with intensity). Activity levels of calpain and calpastatin were measured in samples of LD muscle remove from each carcass 45 minutes after slaughter.
Relationship between the rates of production of gas and VFA during in vitro incubations of high temperature dried grass
Authors: Rymer C. , Givens D.I.
Published: November 2021

The gas production (GP) profile of a feed is complicated by the fact that in addition to the ‘direct’ gas produced as a result of fermentation of substrate to gaseous products, there is also a proportion of ‘indirect’ gas produced. This indirect gas results from VFA produced during the fermentation reacting with bicarbonates in the incubation medium. If the VFA are produced at a different rate from total gas, then the estimation of the direct GP profile is more difficult. The object of this experiment was to observe whether there were any differences in the rates of gas and VFA production during the in vitro incubation of high temperature dried grass (HTDG), and how this might affect the shape of the GP profile produced.
A low tech in vitro procedure using faecal liquor for the estimation of digestibility of Forages
Authors: Omed H.M. , Faza A. , Axford R.F.E. , Ap Dewi I. , Givens D.I.
Published: November 2021

Two-stage techniques Tilley & Terry (1963) for the estimation of digestibility have 3 main disadvantages for use in developing countries with limited laboratory facilities. Carbon dioxide is needed to saturate the buffers; a centrifuge is necessary to separate residues from solubilised materials; and the methods uses pepsin as a proteolytic agent. The aim of the present study was to eliminate these three requirements for the faecal liquor method ( Omed et al., 1989), by replacing bicarbonate with phosphate buffer (Marten & Barnes, 1980), pepsin with biological washing liquid, and centrifugation with sedimentation.
A comparison of the gas production profiles of fresh and dry forage
Authors: Nagadi S. , Herrero M. , Jessop N.S
Published: November 2021

The aim of using any in vitro method is to obtain a good description of the nutritional value of forages as they are fed, which in most cases is on a fresh basis. The in vitro gas production technique has the potential to characterise fermentation pattern of the carbohydrate fractions of forages, and has been used extensively with forage material that has been dried and ground through a 1mm screen. The objective of the present study was to compare the fermentation patterns of fresh and dry forage.
In vitro fermentation characteristics of soya bean cell walls separated from hulls and endosperm
Authors: van Laar H. , Tamminga S. , Williams B.A. , Diekema B. , Burgers W. , Groeneveld D. , Hoogendoorn M.
Published: November 2021

When analysing the fermentative breakdown of cell wall material in plants it is important to realize that it is not homogeneous. The cell walls are composed of different cell wall types which can differ in both their breakdown characteristics and composition. In this experiment in vitro cumulative gas production (Theodorou et al., 1994) was measured to study breakdown characteristics of cell walls from hulls and endosperm of soya beans.
Effect of crude protein level and degradability on performance and rumen fermentation in weaned beef heifers fed a concentrate-barley straw diet ad libitum
Authors: Devant M. , Ferret A. , Calsamiglia S. , Casals R. , Gasa J.
Published: November 2021

Because high quality forages are scarce and expensive, most Mediterranean countries traditionally follow a “barley-beef” system. Within a few weeks after switching to a dry feed diet, the progressively weaned calf is able to digest its diet as efficiently as adult ruminants (Anderson, 1987; Lalles and Poncet, 1990). Assuming that in high concentrate diet enough energy is available, the level and degradability of protein may influence the amount and quality of AA supplied to the duodenum and total nitrogen excretion in faeces and urine. The objective of this experiment was to study the effect of crude protein and degradability level on performance and rumen fermentation in weaned crossbreed beef heifers from 100 to 230 kg body weight fed with high concentrate rations.
Impact of additional protein on nitrogen retention and amino acid absorption from small
intestine in mature steers fed on grass silage
Authors: Kim E.J. , Evans P.R. , Evans R.T. , Parker D.S. , Scollan N.D.
Published: November 2021

The efficiency of dietary nitrogen use on ruminants fed on forage is poor and this may be largely attributed to an asynchrony between the supply of energy and nitrogen to the rumen microbes, resulting in poor microbial protein synthesis and a low efficiency of utilisation of absorbed amino acid (AA). One of the main factors contributing to the latter is the efficiency of absorption of AA from the small intestine and it has been concluded that a value of 0.75 is appropriate across a range of diets (MacRae and Reeds, 1980). However, it is uncertain how this value may vary on grass silage diets and what effect additional rumen undegradable protein may exert. The objective of this experiment was to measure body nitrogen utilisation and AA absorption from the small intestine in steers fed on grass silage or supplemented with fishmeal.
Urinary excretion of allantoin in steers fed on cereal based diet infused with different levels of urea-casein
Authors: Martín-Orúe S. M. , Balcells J. , Vicente F. , Guada J. A.
Published: November 2021

Values of ammonia concentration in rumen liquid have been used as an index of nitrogen requirements of rumen microflora even though ammonia requirements seem to depend on the type of diet. Cellulollitic flora mainly use ammonia as N source, while bacteria that ferment non-structural carbohydrates use either ammonia or protein nitrogen. The aim of this experiment was to establish the minimum concentration of ammonia to optimise microbial synthesis in the rumen of steers fed concentrate-based diets.
Effect of suckler cow breed type on voluntary silage intake, body reserves mobilisation, milk yield and calf performance
Authors: McGee M. , Drennan M.J. , Caffrey P.J.
Published: November 2021

The increased retention of within herd replacements will inevitably result in an increasing proportion of continental breed (mainly Charolais) in the suckler cow herd. Due to the high costs of silage production, winter feeding of suckler cows is expensive and thus cows are generally allowed to mobilise body reserves in winter. The objective of this study was to compare the voluntary intake of grass silage and performance of spring calving Charolais (CH) and Beef x (Hereford and Limousin) Friesian (BF) suckler cows and their progeny during the winter period.
Nutritional management of dual-purpose youngstock in Costa Rica 1. A dynamic characterisation of management intensity and productive orientation
Authors: Solano C. , Perez E. , Vargas B. , Herrero M.
Published: November 2021

Dual-purpose (milk and beef) farms in the tropics are characterised by 1) a high variability of nutritional management systems, and 2) their flexibility to adapt to changing conditions. An appropriate characterisation and classification of these systems is necessary to determine efficient and sustainable resource management strategies according to the different goals or productive orientation of the farms. A prospective study for characterising the nutritional management systems of dual purpose farms in Costa Rica was carried out. The dynamics of the farms, in terms of management intensity and productive orientation, are described and discussed.
Nutritional management of dual-purpose youngstock in Costa Rica 2. Pre-weaning growth performance
Authors: Solano C. , Perez E. , Vargas B. , Herrero M.
Published: November 2021

The growth performance of youngstock has a double effect on the general productivity of dual purpose farms. First, it directly influences the beef outputs of the farm, and second; it has an indirect effect on the length of the non-productive period of the replacement heifers and their subsequent milk production ability. The latter effect has been well documented on dairy heifers in both temperate and tropical conditions. The growth performance of youngstock is dependent of the management intensity and productive orientation of the farm. This paper shows the effect of a series of nutritional factors and farming characteristics on the pre-weaning growth performance of youngstock in eighteen dual purpose farms in Costa Rica.