bluuebunny/crossref_metadata_2025 huggingface dataset:
An evaluation of in-vitro fertilised (IVF) beef embryos
Authors: Stewart M. , Broadbent P.J. , Dolman D.F. , McMillan D
Published: June 2019

A pilot study has been carried out in North East Scotland by the Scottish Agricultural College (SAC) Aberdeen, Buchan Meat and Animal Biotechnology Cambridge (ABC), transferring in-vitro fertilised (IVF) bovine embryos to cattle in commercial diary and suckler herds. The pilot study was undertaken with the co-operation of veterinary practices in the area.

The embryos were produced entirely in-vitro, using ovaries removed from beef heifers post slaughter as a source of oocytes. The heifers were selected pre and post slaughter for breed, health, conformation and fatness. The oocytes were allowed to mature for 24 hours and then fertilised using frozen/thawed semen from top quality beef bulls. These sires were selected for breed, ease of calving, conformation, growth and ability to fertilise in-vitro. Forty-eight hours after insemination the developing embryos were transferred to a co-culture system. After 4 to 5 days of culture the embryos had developed to the morula/blastocyst stage, and were ready for transfer. The recipients’ oestrus cycles were synchronised using a combined PRID and prostaglandin programme. The PRID was inserted on day 1 of the programme and withdrawn on day 9 or day 10 of the programme.
The effect of treatment with a gonadotrophin releasing hormone on the fertility of dairy cows
Authors: Drew S.B. , Peters A.R.
Published: June 2019

Work in New Zealand has suggested that treatment of dairy cows with buserelin an analogue of GnRH between days 11 and 13 after insemination can increase pregnancy rate by reducing embryo loss (MacMillan, Taufa and Day, 1986). This effect is probably mediated via a luteoprotective mechanism (MacMillan, Thatcher & Drost 1989; Thatcher, MacMillan, Hansen & Drost, 1989). The present study was carried out to attempt to confirm this effect of buserelin under UK conditions.

A total of 660 Holstein/Friesian cows on 10 commercial dairy farms were used. The cows were paired according to date, of previous calving and allocated at random to control or treated group on the day of service. Only cows in the parity range 1-5 with no obvious reproductive disorders were used. Bulls and inseminators were used on the same number of cows in each group. Milk samples were taken on the day of service for progesterone assay. Cows not in oestrus were removed from the study. Cows in treated groups were given an intramuscular injection of 10 ug buserelin [2.5 ml Receptal, Hoechst] 12 days after first insemination. Cows not observed to return to oestrus before Day 24 were re-sampled for progesterone assay. Pregnancy was confirned by palpation or ultrasonic scanning at six weeks.
MOET in Suffolks: Increasing the superovulation rate
Authors: Dingwall W S , Fernie K , FitzSimons J , McKelvey W A C
Published: June 2019

Theoretical studies show that rates of genetic progress in sheep could be increased by 100% through use of multiple ovulation-embryo transfer (MOET) to Increase selection intensity amongst females and reduce female generation intervals (Smith, 1986). However, there has been a slow uptake of this technology In breed Improvement programmes due to 2 main problems: (a) surgical interference with donor and recipient animals; (b) poor repeatability of superovulatory response. The first of these problems has been adequately resolved by development of minimally Invasive techniques for the recovery and transfer of embryos by laparoscopy (McKelvey, Robinson and Aitken, 1985a). The main Impediment to rapid dissemination of MOET is now the problem of inconsistent repeatability of superovulatory responses. Pregnant mare's serum gonadotrophin (PMSG) Is the most widely used gonadotropin for superovulating sheep but significant variation in ovulation rate has been reported amongst individual animals (Smith, 1988). However as the predicted genetic gains assume that MOET can consistently produce 4 progeny per donor ewe, what Is achieved in practice falls far short of the theoretical maximum. Several researchers have suggested that higher ovulation rates and less individual variation in ovulation response occur with porcine follicle stimulating hormone (FSHp) compared with PMSG (Armstrong and Evans, 1983; Moor, Kruip and Green, 1984). Compared to the single treatment of PMSG, successive treatments of FSHp are required for 3-4 days to induce superovulation due to the short half-life of the FSH molecules in FSHp.
Milk protein precursors in lactating goats
Authors: Bequette B J. , Backwell C. , Lobley G.E. , MacRae J.C.
Published: June 2019

With the failure of current nutritional schemes for dairy ruminants to predict yields of milk and milk components, and perceptions of milk's nutritional value following recommendations to reduce dietary fat intake, an integrated approach to feeding and metabolism needs to be developed. Such a system must therefore be ‘metabolite’ based.

An ability to predict changes in milk constituent output in response to alterations in nutrition requires, in the first instance, the identification of specific precursors for milk component synthesis in the lactating mammary gland. Arteriovenous differences across the mammary gland indicate that blood free amino acids (AA) are either taken-up by the gland in excess, equal to, or in insufficient amounts compared to their output in milk (1). Isotope labelling experiments have indicated that, in addition to AA free in blood, the mammary gland utilises a substantial amount of AA derived from constitutive mammary gland protein breakdown (2). The present experiment was designed to investigate the AA precursors and kinetics of milk protein synthesis and to confirm and extend the latter observations.
The use of embryo transfer in ruminant genetic improvement programmes
Authors: Simm G
Published: June 2019

Over the course of the last 40 years or so increasingly reliable procedures have been developed for multiple ovulation, embryo recovery and embryo transfer, initially for cattle (see review of Woolliams and Wilmut, 1989) and, more recently, for small ruminants (McKelvey and Robinson, 1986). During this time a number of applications have been proposed or practised. These include uses in (i) within-breed genetic improvement programmes, (ii) the import and export of genetic material (offering potential advantages in economy, animal welfare and disease control), (iii) accelerating breed substitution by multiplication of newly introduced breeds and (iv) conservation of genetic material (by freezing embryos) from valuable individual animals, or from rare or endangered breeds or species. Additionally, there are several new ‘reproductive’ procedures available or being developed for use in animal production (eg. in vitro fertilisation, embryo sexing, cloning, gene transfer) which hinge on the use of embryo transfer. These are discussed in detail by Woolliams and Wilmut (1989) and in the following two papers. The aim of this paper is to examine the first of the applications listed above - the use of multiple ovulation and embryo transfer (MOET) in within-breed genetic improvement programmes.
Prospects for the molecular genetic manipulation of livestock
Authors: Wilmut Ian
Published: June 2019

Molecular genetic manipulation can now be used to produce pharmaceutical proteins in the milk of farm animals. In the longer term this technology will be used to modify aspects of animal production, but it is not clear how many manipulations will be useful nor when such applications will become practicable. Improvements are required in all four aspects of an effective scheme for either gene transfer or targeting: it must be possible 1). to make the change, 2). to regulate expression of the gene in the desired manner, 3). to identify genes that are able to have a significant effect and 4). to disseminate the change into the target population.

There is only one method that has been used to transfer a gene in livestock and this depends upon injection of a few hundred copies of the gene into a nucleus in the early embryo. It is believed that integration occurs because the act of injecting fluid causes breakages in chromosomes and that the repair mechanisms sometimes include injected DNA. There are serious implications.
Future prospects for embryo multiplication by nuclear transfer
Authors: Galli C. , Moor R.M.
Published: June 2019

The propagation of genes from farm animals of superior genetic merit is presently most rapidly achieved by superovulation and embryo transfer. Although these procedures increase the number of offspring from superior females, genetic uniformity and predictability are not guaranteed because of the diversity introduced by genetic recombination at meiosis. To overcome this problem, techniques that generate identical embryos from a single founder have been devised. Embryo splitting and blastomeres separation represented the first approaches to embryo multiplication, but both these techniques are severely limited by the very small clone size which rarely exceeds two offspring. Nuclear transplantation has the potential to produce far larger number of identical embryos but is technically more difficult and involves three separate procedures. Firstly, a source of nuclei, or so called caryoplasts, in an appropriate undifferentiate state is required. Secondly, a supply of enucleated host cells or cytoplasts is essential for the support of the transplanted nucleus.
The activity and straw directed behaviour of pigs offered foods with different crude protein content
Authors: Jensen M.B. , Kyriazakis I. , Lawrence A.B.
Published: June 2019

Pigs are believed to posses a strong motivation to perform exploratory behaviour, which include a range of activities such as walking, orientation towards stimuli and direct investigation. Under free-ranging conditions these activities often occur in connection with foraging (Stolba and Wood-Gush, 1989). In ad libitum fed young growing pigs the provision of straw has been found to stimulate various behaviours involving direct investigation of the straw (e.g. Fraser et al., 1990; McKinnon et at., 1989). As it is assumed that growing pigs under such ad libitum conditions ingest sufficient nutrients, it is often assumed that the straw directed behaviour is unrelated to feeding motivation. However, individual pigs offered single diets may not be able to meet their nutritional requirements (Kyriazakis et al., 1990), and this may have behavioural consequences. For example, the straw directed behaviour observed in growing pigs may be a reflection of unfulfilled nutritional demands and in fact represent appetetive foraging. The aim of the present experiment was to assess the extent to which the exploratory activity of growing pigs is affected by limitations in nutrient intake (specifically the crude protein content of the food).
The relationship between feed composition and the efficiency of protein utilisation in young pigs
Authors: Kyriazakis I , Emmans G C , Taylor A J
Published: June 2019

The quantification of the relationship between feed composition and the efficiency of protein utilisation is a critical step in any model intended to predict the responses of an animal to its diet as rates of protein and lipid retention. Current descriptions of this relationship propose that the efficiency of protein utilisation (ep) is constant and independent of energy supply (Stranks et al, 1988), that ep is a function of protein intake only (ARC, 1981) or that it is a complicated function of the supply of energy at constant protein intake (Fuller and Crofts, 1977). The objective of the two experiments described here, was to define the form of the relationship between feed composition and ep, by using suitable experimental designs.
The influence of protozoa in ruminant digestion
Authors: Jouany J.P. , Bohatier J. , Senaud J. , Toillon S. , Fabre M.
Published: June 2019

Although ciliate protozoa make up 50 % of the total microbial biomass of the rumen and play an active part in the degradation of feed, some authors have shown that animal performance is sometimes improved if they are eliminated. We have been working on a research project to determine the effect of the presence of certain genera of protozoa on digestion in ruminants.
The effect of fixed effect model and prior estimates on sire ranking in a suffolk sire referencing scheme
Authors: Pollott G.E. , Guy D.R.
Published: June 2019

Terminal Sire breeds have a considerable impact on lamb production in Britain’s stratified cross-breeding sheep industry. MLC (1988) estimated that 69% of lambs used for meat production are sired by the Terminal Sire breeds. The predominant Terminal Sire breed is the Suffolk, comprising 46% of the ram population in Britain. The genetic improvement of meat production characters has, traditionally, been difficult in this breed due to the large number of small flocks making up the breed, the restriction on AI use and the lack of a cost/effective central testing facility. However, the formation of the Suffolk Sire-Referencing Scheme Ltd (SSRS), in 1989, has provided a vehicle for faster genetic progress in the breed.
Effect of malt distillers wet grains on lamb finishing and carcass lipid composition
Authors: Vipond J E , Lewis M , FitzSimons J , Noble R C , Horgan G
Published: June 2019

The Scotch whisky industry produces 220,000 tonnes/annum of malt distillers wet grains or draff (D) used mainly as a component of cattle diets, its use in lamb finishing diets has not been widely investigated. Owing to the high level of unsaturated fat in draff there exists a possibility that unsaturated fatty acids may escape rumen biohydrogeneration and have effects on tissue fatty acid composition with important implications for human health.

The purpose of this experiment was to determine the optimum level of supplementary barley to feed with ad libitum draff by comparing diets based on ad lib mineralised draff (D), ad lib draff + 0.3 kg/day barley (DB1) and ad lib draff + 0.6 kg/day barley (DB2). The effect of replacing concentrates in a silage based diet with draff was examined by comparing a diet of ad lib silage + 0.6 kg/day compound (SC) with ad lib silage + 2.1 kg/day draff (0.57 kg dry matter) (SD).
Correlated responses in slaughter and carcass traits of crossbred progeny to selection for carcass
lean content in sheep
Authors: Cameron N.D.
Published: June 2019

A divergent selection experiment in a terminal sire breed of sheep was started in 1985 to examine the differences between genetically lean and fat animals, which were derived from the same population. Responses in performance and physiological traits measured on the selection lines were reported at the BSAP 1991 Winter Meeting. Responses In slaughter and carcass traits, measured on crossbred progeny of the terminal sires, are presented in this study.

The ram selection index was -0.995 FATD + 0.206 WT20, where FATD and WT20 are the ultrasonic backfat depth and liveweight at 20 weeks of age, with both traits standardised to have zero mean and unit phenotyplc variance. A total of 32 and 34 rams from the high (lean) and low (fat) selection lines were performance tested in 1988, and 11 rams were selected from the high line and 12 rams from the low line for mating to crossbred ewes for the progeny test, with a selection differential of 0.85 Index units. There were 8 and 11 rams from the high and low lines with progeny slaughtered at fixed weight, such that the selection differential was 1.0 Index units. A total of 329 crossbred lambs were slaughtered at 16 weeks of age and 250 lambs were slaughtered at fixed weight, 39±1 kg for castrates and 37±1 kg for ewe lambs.
The effect of in situ composting on nitrogen, micro-organisms and odour emissions from sawdust beds
Authors: Kay R.M. , Smith A.T.
Published: June 2019

Pig production is responsible for 65 per cent of all odour complaints and 10 per cent of water pollution incidents. In addition, the disposal of pig slurry effluent may create major difficulties in nitrate sensitive areas either from run off or leaching of liquids. In situ composting of pig manure has the potential to eliminate these problems whilst encouraging pig producers to use welfare positive, bedded systems. In situ composting is a system of housing in which pigs are contained on a deep bed of sawdust. The bed is actively managed by aeration and the use of commercial additives to encourage composting of excreta as it is produced. The system appears to give an odour and liquid free environment. Such systems cannot be encouraged however until it is clearly established that there are no environmental or health disadvantages.
The utilization of plain sugar beet pulp and wheat straw by pregnant sows
Authors: Yan T. , Longland A. C. , Close W. H. , Sharpe C. E. , Keal H. D.
Published: June 2019

There is a considerable current interest in the feeding of high fibre diets to pregnant sows, with a view to gaining both economic and welfare advantages. The potential use of these diets will depend on the extent to which the fibrous materials are fermened in the hindgut, and the subsequent capacity of the products of the fermentation, that is VFAs, to meet the energy needs of the animal. Sugar beet pulp and wheat straw are two ingredients that have considerable potential as feed ingredients for sows. The present experiment was designed to study the extent to which diets containing high level of non-starch polysaccharides (NSP), largely from plain sugar beet pulp (SBP) or wheat straw (WS), influenced nutrient partition and the efficiency of ntrient utilisation in pregnant sows.
Effect of dietary a-tocopherol on plasma and milk a-tocopherol levels in the sow
Authors: Lynch P. B. , Buckley D. J. , Morrissey P. A.
Published: June 2019

Vitamin E functions as an antioxidant in animal tissues. Deficiency has been associated with sudden deaths in suckling and growing pigs as well as impaired immune function and reduced fertility. Of the tocopherols and tocotrienols present in nature, only a-tocopherol (a-T) appears in appreciable amounts in pig blood and tissues. A previous trial (Monahan et al., 1990) had shown that feeding a diet containing a high level of a-tocopherol to sows from day 3 of lactation resulted in a significant increase in sow plasma, sow milk and piglet plasma a-T levels. The present trial was designed to study the effect of feeding high a-T from late pregnancy or from farrowing on milk a-T levels.
The practical implications of animals responses to man (specifically effects on production parameters)
Authors: Seabrook Martin F. , Bartle Nicola C.
Published: June 2019

The paper outlines the major problems in scientifically assessing the nature and quality of the man-animal interface and the difficulties in isolating its effects on animal production. Research epistemologies in this area are thwart with difficulties as it is virtually impossible to isolate individual factors. For example, while it is possible to devise ‘pleasant’ and ‘unpleasant’ handling treatments; as defined by level and nature of the physical interaction of the human body with that of the animal; it is not possible to separate physical handling from aspects such as voice tones, gestures, smell, sound of foot movements, or other ‘vibes’ transmitted in the experiment. Thus, any changes in ‘production’ may arise from a number of inter-woven components. It is also of relevance that the quality of the man-animal interface is a perceived construct and that the animal may perceive both applied ‘pleasant’ and ‘unpleasant’ stimuli as undesirable. Limitations of research paradigms are raised, for example, in experimental situations the environment may well be ‘richer', and with more humans present, than in commercial situations. The nature of the interface may thus be somewhat different.
An examination of the effect of type of concentrate and method of concentrate feeding on the milk production of british friesian dairy cows offered grass silage based diets
Authors: Agnew K W , Mayne C S
Published: June 2019

In a previous study at this Institute, significant increases in total dry matter intake were obtained with first lactation animals offered grass silage and concentrates as a complete diet rather than in separate feeds. However, the increased DM intake associated with complete diet feeding was not reflected in improved animal performance. Similar results have also been reported by Phipps, Bines, Fulford and Weller (1984) and Cassel, Merrill, Milligan and Guest (1984).

The aim of this experiment was to investigate the effect on animal performance of offering two types of concentrate in addition to grass silage, with concentrates offered either as a complete diet or in three feeds per day.
The Effect of Protein Content of the Supplement on Milk Production of Dairy Cattle offered Low and High Digestibility Grass Silage Ad Libitum
Authors: Mayne C S
Published: June 2019

Previous studies at this Institute have shown a marked interaction between level of supplementary feeding and protein content in the supplement with dairy cows offered high quality grass silage-based diets. For example, a given milk yield or yield of milk constituents can be obtained by offering supplements of high crude protein (CP) content, eg 340 g CP/kg fresh weight, at much lower levels than would be required with conventional supplements with a CP content of 180 g/kg fresh weight. The aim of the present study was to quantify if. the interrelationships established with high digestibility silages also applied with lower digestibility silage.

The experiment was carried out with 60 autumn-calving British Friesian dairy cows. Twenty eight animals were offered early cut silage (E), harvested between 17-19 May, with the remaining thirty two animals offered late cut silage (L) harvested between 2-12 June. Both E and L silages were produced from the same swards and in both cases grass was direct harvested and treated with an inoculant of Lactobacillus plantarum, at the rate of 3.0 litres/t fresh herbage.
The development of in vitro fertilized (ivf) cattle ova in an oviduct cell co-culture system
Authors: McCaffrey C. , Diskin M.G. , Lu K.H. , Sreenan J.M.
Published: June 2019

There have been many recent reports of the successful production of large numbers of in vitro matured (IVM) and in vitro fertilised (IVF) cow ova. While a high proportion (80-90%) of oocytes undergo apparently normal maturation and fertilisation in vitro, only 15-20% develop in vitro to the morulae and blastocyst stages. Early cleavage stage in vivo matured and fertilised cow ova also encounter a developmental “block” at the 8-16-cell stage during in vitro culture in conventional culture media. However, this block has been readily overcome by co-culture involving the use of bovine oviducal cells, with up to 80% of 1-4-cell ova developing to morulae and blastocysts: The present study examined the development of IVM-IVF cattle ova removed at 24 or 48 hours from the insemination medium and cultured on cattle oviducal cells and also compared the development of IVM-IVF and in vivo produced ova in the same oviducal cell co-culture system.
Increased ovulation and twin-calving rates in heifers immunized against bovine inhibin peptides
Authors: Morris D.G. , Diskin M.G. , Sreenan J.M.
Published: June 2019

Inhibin is a dimeric protein hormone composed of two dissimilar, disulphide-linked subunits (termed α and β) involved in the negative feedback regulation of gonadotrophin secretion, preferentially FSH. Interfering with this negative feedback by active immunization against inhibin has resulted in a consistent increase in ovulation rate and litter size in sheep. However, similar results have not been achieved in cattle. This paper describes the effect of active immunization of heifers against either of 3 synthetic peptide sequences from the bovine inhibin α-subunit on inhibin antibody titres, ovulation rate, calving rate and twin-calving rate.

Three peptide sequences from the bovine inhibin a-subunit were identified as likely immunological epitopes by computer analysis. These peptides (P1: bl-α-[YG] (18-30); P2: bl-α-(63-72)[GY]; P3: bl-α-[CG](107-122) were synthesized by solid phase methods and tyrosyl or cystenyl residues, linked through a glycine spacer where appropriate, were added during synthesis in order to facilitate iodination and conjugation respectively.
Strategic issues facing the european dairy industry post 1992
Authors: Doyle C. J.
Published: June 2019

Much has been written about the changing structure of dairy farming in Europe in the last decade, but comparatively little has been said about the processing sector. Yet the future market for milk largely depends on the success of the dairy trade in adapting to the new market environment. Accordingly, this paper concentrates on the pressures and strategic issues facing the milk processing sector in Europe. Certainly, in recent years it has had to cope with radical changes in both the production and consumption of dairy products. After several decades of uncontrolled expansion in milk production, the introduction of milk quotas by the European Community in 1984 was a rude shock. In general, the industry was still geared to an expanding milk market. Almost overnight, it was faced with the problem of excess processing capacity.
The efficiency of artificial insemination in pigs : lessons from australian research
Authors: Dunne John
Published: June 2019

Recent years have seen a small but consistent growth in the use of AI on commercial pig farms in Britain. Currently about 12 percent of all matings are artificial and 25 percent or more of farms are using some AI.(6) This figure still falls well short of our continental neighbours, with Denmark and the Netherlands inseminating 50 percent of their sows. The conception rate and litter size achievable with AI (6) can at least equal results from natural matings. However, it is recognised that some people achieve far superior fertility results to others when using AI. Part of this is due to different genotypes employed (e.g. purebreds vs crossbreds), different production systems and management practices imposed. It is most likely, however, that an unquantified but substantial part of the reason for such big differences between farms in fertility following AI is due to differing abilities of stockpeople performing the inseminations. “Ability’ refers not only to the actual insemination technique, which is straightforward and can be quickly learned, but to their general ability to recognise behavioural changes in their stock, to interact with their stock and generally get the best out of their stock i.e. their level of stockmanship skills.
Active immunization of young male calves and post pubertal bulls against lhrh with various conjugate doses
Authors: Carson A.F. , McCaughey W.J. , Steen R.W.J.
Published: June 2019

In comparison to steers bulls slaughtered at the same age have produced 14% more carcase gain and 20% more lean meat. Immunological castration which is reversible may reduce aggressive behaviour and maintain the performance advantages of bulls. Active immunization against luteinising hormone releasing hormone (LHRH) reduces LH and testosterone production and, therefore, aggression in bulls (Robertson et al. 1982). However, a controlled predictable response to vaccination has not been achieved. This may be due to suboptimal choice of a number of variables in the vaccination programme. This study investigated the effect of conjugate dose and age of the animal on the anti-LHRH antibody response in bulls.

Synthetic LHRH (UCB Bioproducts) was conjugated to keyhole limpet haemocyanin (KLH) (Sigma Chemical Company) using a modification of the novel carbodiimide method reported by Deen et al. (1990). New batches of conjugate were prepared for each vaccination. The efficiency of incorporation of radiolabelled LHRH varied between 40 and 45%.
The effect of pheromones from cows in oestrus on the duration of the post-partum anoestrous period in beef cows
Authors: Wright I.A. , Rhind S.M. , Smith A.J. , Whyte T.K.
Published: June 2019

The term pheromone is used to describe a substance that is produced by an animal and creates a response in other Individuals of the same species.

Reproduction in females can be affected by pheromones from other females in a number of mammals. This can invoke a degree of synchrony of oestrous cycles in for example the hamster (Handelmann et al, 1980) and the human (McClintock, 1971). Izard and Vandenberg (1983) demonstrated that in heifers which had their oestrous cycles synchronised using exogenous prostaglandin the degree of synchrony was enhanced when they were exposed to cervical mucus from cows in oestrus. They suggested that cervical mucus from cows in oestrus contains a pheromone which can enhance the degree of synchrony of oestrus in heifers.
The effect of replacing fishmeal with carbohydrate on the feed intake and growth of turbot (Scophthalmus maximus L.)
Authors: Calcedo I. E.
Published: June 2019

The feeding of turbot during the on-growing phase is done with highly proteinaceous feeds, raw fish and fish meal being the main ingredients. The protein of these feeds is used inefficiently because the amino acids of the protein are metabolised to produce energy instead of contributing to protein growth (Cacho et al. , 1990). Alternative sources of energy, such as carbohydrate, are known to spare protein (Hepher, 1986). The aim of this experiment was to test the idea that fish given free access to feeds with different protein: carbohydrate ratios will (a) eat enough feed to meet their protein requirement and (b) maximise their efficiency of use of protein for growth when a sufficient supply of an alternative source of energy (carbohydrate) is available.
Environmental implications of nutrition and metabolism of salmonids
Authors: Carter C.G. , Houlihan D.F. , McCarthy I.D. , Mitchell A.I. , Buchanan B.
Published: June 2019

In farmed salmonids the majority of consumed nitrogen is lost in metabolic waste products (mainly ammonia) and the faeces (Table 1). Any improvement in nitrogen retention, brought about by reductions in these components, would decrease environmental load. Inter-individual variation in retained nitrogen has been little investigated as a basis for selection of more efficient fish; this communication points to an experimental approach to measuring individual variation by concentrating on digestive efficiency and protein turnover as possible contributors to nitrogen retention. The utilization of dietary nitrogen was investigated in two species of farmed salmonid, the rainbow trout, Oncorhynchus mykiss and the Atlantic salmon, Salmo salar.
Ascorbic acid: a limiting nutrient affecting performance and physiological response of broiler chicks under heat stress
Authors: Kutlu H.R. , Forbes J.M.
Published: June 2019

Birds are normally able to synthesize adequate amounts of ascorbic acid (AA). However, there are many indications that under stress they cannot produce enough AA for their metabolic needs. In particular, heat stress has been implicated in increasing birds’ demand for AA (Scott, 1975; Sykes, 1978; Coates, 1984). These reports suggest that conditions may exist in which endogenous AA synthesis of birds is not adequate to meet the physiological needs for optimum performance and that during such conditions exogenous supplementation with AA could be beneficial. This study was conducted to determine if dietary supplemental AA would alleviate heat-induced deterioration in performance and metabolism of broiler chicks and also to characterize the changes in body temperature, thyroid weight and blood components as affected by supplemental AA and/or heating.
Egg production and quality: effects of vicia faba in laying hen diets
Authors: Scaife J. R. , Amare Abeba , Acamovic T. , Michie W. , Davis M.
Published: June 2019

Vicia faba has considerable potential as a protein supplement for farm livestock in many parts of the world. The protein content varies depending on cultivar but has been reported to range from 230 - 390 g/kg (Garrido et al 1991) The extensive use of vicia faba in laying hen diets has been limited by the, presence antinutrients such as tannins, lectins and pyrimidine glucosides which have been reported to decrease protein digestibility (Lacassagne et al. 1988) and adversely affect egg production and quality parameters such as egg number and egg weight (Guillume et al 1977). The production of low tannin cultivars of vicia faba has increased interest in its use in poultry feeds and an experiment was conducted to investigate the effects on egg production and quality of inclusion of whole ground beans; cotyledons or hulls from one such low tannin cultivar ‘Toret’.
Reduction of intestinal viscosity in barley-fed broilers by β-glucanase: Site of action and effect on bird performance
Authors: Bedford M.R. , Classen H.L.
Published: June 2019

The objective of this research was to determine the site of dissolution of viscous polysaccharides in the intestinal tract of birds fed a barley-based diets and the site of action of enzymes designed to degrade such polymers. A barley-based diet (60% Condor variety, 4.58% β-glucan) was fed with and without β-glucanase supplementation to broilers from 1-21 days of age (4 replicate pens of 5 birds per pen), at which time weight gain, feed intake and viscosity of digesta supernatant (12,500 x g, 5 min) from the gizzard, first and last half of the small intestine was measured. Two β-glucanase sources were tested, a commercial multienzyme product, blended from several microbial and fungal fermentations containing β-glucanase, xylanase and amylase activities (Avizyme Sx, Finnfeeds International Ltd., BG1) and a single Trichoderma fermentation source of β-glucanase (BG2). Each enzyme was added at 250 β-glucanase U/g (pH 6.8) feed. Addition of BG1 and BG2 improved weight gain by 28 and 28% respectively (p<0.0001) and FCE by 23% and 18% respectively (p<0.0001). Viscosity in the gizzard, first and last half of the small intestine was 10, 88 and 270 cp respectively in control broilers, an unacceptably high set of values, particularly in the hind-gut. Addition of either enzyme source significantly reduced viscosity in all gut sections and prevented the increase in viscosity noted in control fed birds. Foregut intestinal viscosity correlated well with weight gain (R2=0.907, p<0.0001) and FCE (R2=0.871, p<0.0001). The variance associated with weight gain and FCE was substantially reduced with enzyme addition, but particularly so with BG1. BG1 tended to reduce gizzard viscosity to a greater extent than BG2 suggesting that it is either more active at acid pH or that undefined associated activities (eg glucosidase) are necessary for optimum viscosity reduction.
Behaviour-environment interactions in hens: implications for housing design
Authors: Appleby M.C.
Published: June 2019

Intensive housing systems are often criticised for preventing certain behaviour, or for constraining appropriate matching of behaviour and environment. However, the effects of such behavioural restriction on animals will depend on the way in which the behaviour is controlled and the way in which it interacts with the environment. This is particularly important where facilities are being provided for animals. Behaviour-environment interactions were investigated in laying hens.
Use of a ‘Floor’ method instead of metabolism crates for collecting faeces from goats, for estimating digestibility of dry matter
Authors: Velásquez Jaime E. , Owen Emyr
Published: June 2019

Total collection of faeces from goats fed long straw ad libitum in crates requires much labour. This is particularly so when feeding straw generously to facilitate selection by goats of the more nutritious leaf-plus-sheath component (Wahed, Owen, Naate and Hosking, 1990). Confining goats in crates is also stressful to animals and in future will be discouraged. An experiment was therefore made to compare the digestibility of barley straw supplemented with concentrates, measured by collecting faeces in one of two ways. One involved total collection of faeces from goats confined in metabolism crates. The other involved estimating the output of faeces from the increase in weight of sawdust bedding provided for individually-penned goats.
The effect of genotype on fibre production in cashmere goats
Authors: Gallagher M , Waterhouse A
Published: June 2019

Commercial cashmere production in the UK is at an embryonic stage. Native feral goats (F) have been crossed with imported stock from Iceland (I), Australasia (A) and Siberia (S) to improve fibre production. At present there is little published data on the amounts and quality of fibre produced from these genotypes and their crosses.

The objective of this study was to establish the extent of the variation in fibre production characteristics, namely fleece weight, yield and down production between the above genotypes and also to estimate the likely improvements made from crossing these pure bred genotypes.
The effect of varying protein degradability on mohair fibre characteristics and liveweight gain in angora goats
Authors: Austin S.A. , Aliakbar D. , Cooper R.A. , Kirk J.A.
Published: June 2019

The primary objective of Angora goat producers is to optimise yields of high quality mohair, characterised by long staples of fine fibres. There is also now an increased interest in the concurrent production of goat meat as an additional source of income. Protein supplementation has been shown to affect mohair yield, quality and liveweight gain in Angora goats both in the USA (Shelton and Huston, 1966) and more recently in the UK (Shahjalal et al., 1991). Throckmorton et al. (1982) detected an improvement in liveweight gain and fibre production when Australian Angoras were fed a supplement high in rumen undegradable protein (UDP) but the effect of protein degradability has not yet been established, particularly under UK conditions. The aim of this trial was to determine the effect of varying protein degradability on yield, staple length and fibre diameter of mohair, and on liveweight gain of British Angora goats.
Responses of Matebele goats of Zimbabwe to feeding level: late pregnancy
Authors: Majele Slbanda L , Bryant M.J. , Ndlovu L.R.
Published: June 2019

Under conventional husbandry conditions, Matabele goats kid all year round and, as they receive no supplementary feed, they are frequently exposed to periods of feed scarcity. The aim of this experiment was to determine maternal and foetal responses to different feeding levels during pregnancy.

The work was carried out at the Thuli Breeding Station, in Matebeleland, south western Zimbabwe. Forty-two Matebele goats carrying single kids were individually penned and randomly allocated to each of three treatments as they reached week 14 of gestation. The treatments were; Low (L)=0.25 MJ ME / kg0.75, Medium (M)=1.5xL and High (H)=2.5xL. Whole maize grain, lucerne hay and veld hay (see Table 1) were offered at levels calculated to provide 0.2, 0.24 and 0.56 of the total ME. Drinking water and an iodized mineral lick were available to all goats ad libitum. Feed intake was measured daily. Does were weighed and body condition scored (on a scale of 1-10) weekly and within 8 hours of parturition. Kids were weighed at or soon after birth.
The relative importance of the amounts of energy and crude protein in the concentrate ration on intake and yields of milk constituents by autumn-calving Holstein-Friesian cows given grass silage ad libitum
Authors: Aston K. , Sutton J.D. , Baker R.D. , Fisher W.J.
Published: June 2019

The response in yields of milk constituents to increases in the amounts of standard dairy concentrate (SC, 200 g crude protein (CP) per kg DM) given to cows consuming grass silage ad libitum were reported recently (Aston et al 1991; Baker et al 1991). A change of level however adjusts the supply of both energy and CP. Previous work also showed .linear responses in silage intake and milk and milk protein yields when CP was increased in a fixed ration of concentrate of constant energy value. In this trial energy and CP levels were varied Independently. The objective was to separate the effects of energy on the performance of lactating cows from those of CP.
Body composition and performance of autumn-calving Holstein-Friesian dairy cows during lactation: non-carcass component weights
Authors: Gibb M.J. , Ivings W.E. , Sutton J.D.
Published: June 2019

In order to understand the complex changes associated with lactation in the dairy cow it is necessary to assess the contribution of the non-carcass components. It has been shown with sheep (Cowan, Robinson, Greenhalgh and McHattie, 1979) that a number of tissues may be mobilised during lactation with a redistribution of tissues particularly towards the gut and udder, and that diet may have a significant effect. Butler-Hogg, Wood and Bines (1985), using Friesian dairy cows showed changes in the weights of guts, internal fat depots (omental, mesenteric and perinephric) and liver with stage of lactation although the number of stages examined was somewhat limited. The present experiment investigates changes in non-carcass component weights at 9 points over the first 29 weeks of lactation and with 3 levels of concentrate supplementation.
Body composition and performance of autumn-calving Holstein-Friesian dairy cows during lactation: velocity of ultrasound measurement
Authors: Ivings W.E. , Gibb M.J. , Dhanoa M.S.
Published: June 2019

Measurements of the velocity of ultrasound (VOS) through live animals have been shown to provide good estimates of the proportions of dissected fat and muscle in carcasses of beef cattle (Fursey, Miles, Page and Fisher, 1991). The use of this technique to measure more accurately the changes in body composition and energy content of the dairy cow over lactation would greatly assist in the interpretation of nutritional studies. Estimation of body reserves from live weight (LW) can be inaccurate due to changes in gut fill, tissue water contents and reproductive tissues, and condition scoring is highly subjective. The present study investigates the relationships of LW and VOS measurements at 3 sites with dissected fat and muscle in the half carcass and chemically determined fat and crude protein (CP) in the whole carcass and empty body.
Body composition and performance of autumn-calving Holstein-Friesian dairy cows during lactation: energy partition
Authors: Cammell S.B. , Beever D.E. , Sutton J.D. , Spooner M.C. , Haines M.J.
Published: June 2019

Previous experiments have demonstrated the effects of diet composition, energy substrate and stage of lactation on the energy balance of lactating Friesian cows (Beever et al 1989). The purpose of the present experiment was to extend these studies by measuring energy balance and respiratory exchange in parallel with direct measurements of changes in body composition by slaughter. (See accompanying summaries).

Nine cows were selected on the basis of age, parity, live weight and previous lactational performance to be similar to those in an associated feeding trial (Sutton et al 1992). They were allocated to 3 (L), 6 (M) and 9 (H) kg DM/day of concentrates (206g CP and 12 MJ ME per kg DM) with grass silage ad libitum (206g CP and 10.4 MJ ME per kg DM). Measurements of energy exchange were made at five stages of lactation, weeks 5, 10. 16, 22 and 28. Gaseous exchange was measured during each stage of lactation for 4 days using open-circuit respiration calorimetry followed by a 6 day collection of faeces and urine.
Effect of energy status on milk production responses to dietary addition of fat in cows
Authors: Martin P.A. , Chamberlain D.G. , Choung J.J. , Robertson S.
Published: June 2019

Adding appropriate fats to diets for dairy cows has the potential to improve the acceptability of dairy products to the health-conscious consumer by increasing the proportion of monounsaturated fatty acids in milk fat. However, concentrations of protein in milk are often concurrently depressed. In these respects responses to fat resemble those seen in animals in negative energy balance, where the contribution of fatty acids mobilized from adipose tissue to milk fat synthesis leads to similar changes in milk fat composition, and milk protein concentrations are relatively low.

These similarities give rise to two questions: (i) do the metabolic adaptations during negative energy balance influence the utilization of dietary fat for milk fat synthesis, and (ii) is the mechanism whereby milk protein is depressed the same in both cases? As a preliminary investigation of this, an experiment was conducted to compare the effects of dietary fat supplementation on performance of lactating cows either mobilizing or depositing body tissue.
Effect of fishmeal and wheat bran diet on the performance of local lactating cows in Bangladesh
Authors: Khan M.A.S. , Akbar M.A. , Topps J.H.
Published: June 2019

Nine local (indigenous) Zebu cows of average body weight 156 kg. were used to examine the performance in their first lactation given either fishmeal or wheat bran diets.

Fishmeal diet (A) consisted of 11.5 kg urea treated straw, 4 kg green grass and 0.25 kg of fishmeal. This diet contained an estimated 63 MJME, 518 g of rumen degradable protein (RDP) and 146 g of undegraded dietary protein (UDP). The wheat bran diet (B) consisted of 11.6 kg urea treated straw, 4 kg green grass and 0.5 kg wheat bran. This diet contained an estimated 66 MJME, 523 g of RDP and 91 g of UDP. Total dry matter intake of the two diets, A and B were 7.5 and 7.83 kg/d respectively. Therefore the two diets differed mainly in UDP levels. The composition and nutritive value of the ingredients of the two diets are given in Table 1 and 2.
The performance of dairy cows fed concentrate and grass silage diets containing moderate and high proportions of concentrate
Authors: Rooke J.A. , Bahman A.M. , Topps J.H.
Published: June 2019

Intensive feeding systems for dairy cows based on a high proportion of concentrates in the diet are becoming popular in many countries where forage resources are scarce. The objective of this experiment was to examine the effects on high yielding cows of feeding diets containing either 700 g/kg dry matter (DM) concentrate or 500 g/kg DM concentrate when grass silage was the forage component.
Use of a norgestomet implant to reduce embryonic loss and resynchronise oestrus in dairy heifers
Authors: Logue D N , Bax J A , Renton J P , McNally J
Published: June 2019

In a recent study of the efficacy of two methods of oestrous synchronisation in dairy heifers, progesterone profiles and ultrasound results showed that late embryonic/early foetal loss had a small but nevertheless important effect upon pregnancy rates (Logue & others 1991). Since some preliminary results were available which showed that the use of a 3 mg norgestomet ear implant alone, rather than in combination with a 3 mg norgestomet and 5 mg oestradiol valerate injection (Crestar Intervet UK Ltd), enhanced pregnancy rates in beef heifers (Favero & others 1989) and the technique was being used in Embryo transfer (ET) recipients (Broadbent pers com) it was felt that a further investigation of the technique was merited.
Genetic parameters and trends for production traits in jersey island heifers
Authors: Mrode R.A. , Swanson G.J.T. , Bellamy H.J.
Published: June 2019

Lactation records of Jersey cattle on Jersey Island are recorded within National Milk Records of England and Wales (NMR). Since it is a closed breed population, it is not possible to amalgamate these data with Jerseys recorded in the United Kingdom (UK). Presently genetic evaluations of Jersey Island bulls are carried out using heifer records with a modification of the model used in the UK to account for the smaller herd sizes. Cows are not evaluated.

The objective of this study was to analyse Jersey Island data in order to estimate genetic parameters and establish genetic trends after evaluating all bulls and cows using an Individual Animal Model (LAM).