In Portugal there is an increasing interest in animal welfare studies directed mainly to the improvement of the housing systems. It is recognised that housing is an important factor that affect the behaviour, the production and the health of dairy cattle (Bowell et al., 2003). However, in Portugal few data on the welfare of dairy cattle are available. Therefore this study aimed to determine some housing, health and other welfare indicators in dairy farms in Northwest of Portugal.

Housed dairy cows spend approximately 4 -5 hours per day eating, and normally stand on a concrete surface during this time. However, concrete surfaces are known to contribute to hoof lesions, and subsequent lameness problems. It has been suggested that improving cow comfort at the feeding area, for example, by providing a more ‘comfortable’ standing surface, may promote total dry matter (DM) intake, and improve hoof health and cow welfare. This study was designed to examine the effect on food intake and cow behaviour of placing matting along the standing area behind a feed barrier.

The interaction between man-animal has a great impact on farm animal welfare and it constitutes an area of dynamic research. Typically the goal this kind of studies is to reach good management practices with lower costs and providing a better welfare to the animals. To evaluate the interaction man-animal many behavioural tests have been developed and applied to different animal species (Pajor et al., 2003; Lansade et al., 2004; Tallet et al., 2006). These tests are used to evaluate relationship between farm animals and their stockperson and how it affects the animal behaviour. The objective of this study is to compare the lamb behaviours of activity and vocalization of two breeds -Île-de-France (IF) and Churra da Terra Quente (CTQ) in a man-animal standard test.

Equine welfare is a major concern within the racing industry. A large proportion of fatalities (50-60%) are the result of falls at fences (Pinchbeck, et al., 2004). Various authors have reported factors affecting fall rates both within steeplechase and hurdle races these include; race length, race speed, ground conditions (the going), the horses Timeform rating, previous history, race progression and whip use (Pinchbeck, et al., 2003; Pinchbeck, et al., 2004). At present there have been few studies carried out investigating the effects of gender on the risk of falling in hurdle racing. This study undertook an investigation of fall rates for hurdlers running during the 2004/05 National Hunt season, discriminating via gender.

Reduced fertility has been had significant impact on economic losses in dairy herds. Ovarian functional disorders are reported as an important cause of infertility in dairy cattle. Among which delayed ovulation affects about 10-15 percent of high yielding cows (Ahmad et al. 1996). Progesterone profiles at artificial insemination (AI) and on day 5 post insemination are related to conception rate. A need for adequate concentration of progesterone in early pregnancy is well established and an insufficiency of progesterone has been implicated as a cause for abnormal development of embryos and early embryonic death. Administration of GnRH during the early postpartum period has increased early ovulation, but the effect on the interval from calving to conception has been variable (Britt et al., 1974; Archbald et al., 1990). This experiment was carried out to determine the effects of GnRH injection at the time of insemination on ovulation rate, conception rate and plasma progesterone concentration on day 5 post insemination.

The widespread use of dairy bull semen in artificial insemination requires that semen production be as efficient as possible. Investigators have shown that low libido is one of the most common problems encountered with bulls and one that frequently leads to culling. In commercial situations, treatment with PGF2α has been used to expedite mounting behavior, as well as restore libido in boars displaying decreased sex drive (Szurop et al, 1985). When administered prior to ejaculation, PGF2α markedly increased the number of spermatozoa in first ejaculates from bulls and rabbits (Hafs et al, 1974). The objective of this study was to determine whether injections of PGF2α in low libido Iranian Holstein bulls can improve semen characteristics and libido.

Over the past decades there has been a substantial decline in the reproductive performance of high-producing dairy cows. The negative energy balance (NEB) early post partum and intake of a high-protein and high-energy diet, are known to cause hormonal and biochemical changes in these cows (Lopez –Gatius et al., 2001). Hence, metabolic and endocrine changes in early lactation allow enhanced mobilization of depot fat and skeletal muscle break down and favour partitioning of absorbed nutrients to the mammary gland to provide sufficient substrate for milk synthesis (Butler, 2002). Anoestrus, a common state during the post partum period in high-producing cows, has major economic implication since it increases the length of the calving interval. Beta hydroxybutric acid (BHBA) is caused by a negative energy balance, and typically is produced within 2 months after calving (Butler, 2002; Noordhuizen, 2003). Anoestrus is a failure to exhibit oestrus behaviour in cyclic cows that classified into the four groups, ovarian atrophy, persistent follicle, persistent corpus luteum and ovarian cyst (Waanga and Janowski, 2000). Therefore, the objective of this study was to investigate the relationships among milk production, glucose, urea nitrogen, phosphorus, BHBA, total protein and progesterone and length of the calving interval.

One possible way to reduce urinary nitrogen (N) excretion is reducing the amount of dietary crude protein fed to dairy cows. In fact, decreasing dietary crude protein (CP) concentration from 184 to 151g/kg, linearly decreased urinary N expressed as gram per day or as a percentage of N intake (Broderick, 2003). Balancing diets for limiting amino acids could improve cow responses fed lower protein diets without increasing N losses in urine. High concentrations of methionine and lysine during early lactation may reduce the risk of metabolic disorders (Berthiaume et al., 2006). A number of blood metabolites are useful as monitors for signs of metabolic disorder. The aim of this experiment was to determine the effect of altering the dietary methionine concentration on some blood metabolite concentrations of early lactating Holstein cows.

It has been indicated that to achieve maximal milk production, a non-lactation or dry period is necessary between lactations (Rastani et al., 2005). A period of 45 to 60 days, generally, has been recommended for the dry period. Shortening the dry period to less than 60 days has been promoted during the past few years (Gulay et al., 2003). Several experiments designed to examine the effect of reducing the dry period, to approximately 4-5 weeks, have shown no difference in milk production and/or fat corrected milk in the subsequent lactation (Gulay et al., 2003). The object of the present experiment was to determine the effect of days dry (30-45 vs. 45-60 days) and diet combination on the first 60 days actual milk production, milk fat and protein concentrations, somatic cell counts (SCC), body condition score and conception rate per first insemination of high producing cows.

The transition phase, typically defined as 3 wk before to 3 wk after parturition, is viewed as a critical time in the lactation cycle of a dairy cow. During early lactation dry matter intake (DMI) lags behind the nutrient requirements for milk yield. So, the onset of lactation in the dairy cow is characterized by a dramatic increase in the nutrient demands for milk synthesis. Fish meal (FM) is used in dairy cow ration as a source of RUP in some countries. Greater rumen escape of FM protein is known to increase efficiency of protein utilization in lactating cows. Moreover, FM has an excellent profile of amino acids and is a good source for the 2 most limiting amino acids for milk synthesis, lysine and methionine. Fish meal also contains oil (8 – 10% of DM) with relatively high concentrations of two polyunsaturated fatty acids (PUFA) of the n-3 family, eicosapentaenoic acid (EPA, C20:5) and docosahexaenoic acid (DHA, C22:6), which can be supplied only by the diet because EPA and DHA cannot be synthesized de novo in mammalian systems. Of the available feedstuffs that are high in undegradable protein, fish meal often is effective in improving milk production. Meanwhile, reports on the effect of fish meal on blood metabolites in pre-and postpartum cows are rare and needs more investigation. The objective of this experiment was to compare diets with or without fish meal from transition period up to 35 days in milk (DIM) and their effects on blood metabolites in early lactation Iranian Holstein cows.

Canola meal is one of the most widely used protein sources in animal feeds. It has an excellent amino acid profile and it is rich in vitamins and essential minerals. Many experiments have been conducted on the value of canola meal for dairy cows. Excellent and often improved milk production has resulted from the use of canola meal as a main protein source. Canola meal provides an important contribution to both rumen microbial protein needs as well as to the digestible amino acids required for animal growth and lactation. Canola meal possesses an excellent RDP profile that may stimulate microbial growth in the rumen. Although canola meal was extensively degraded in the rumen, its 12-h residue still provided an estimated AA profile to the intestinal tract that was close to the AA profile of milk protein (Piepenbrink and Schingoethe, 1998). Kendall et al. (1991) found that the effective degradability of canola meal averaged 51.5%. This compared to 59.1% for soybean meal. In the current animal feed market in Iran, canola meal is cheaper than soybean meal (320 vs. 482 Toman/kg; US $1=933 Toman). The objective of this experiment was to evaluate substitution of soybean meal with canola meal and measure its effects on milk production and composition, and dry matter intake in early lactation Iranian Holstein cows.

Although there is no clear evidence to fully describe the mechanism involved in glucosinolate-related effects on animal reproduction, lowered fertility in animals fed diets with rapeseed meal (RSM) inclusion is related to glucosinolate (Gls) content in the diet (Mawson et al., 1994). The degree of reproduction impairment depends both on glucosinolate content and on the type of animal. Negative effects of feeding high Gls RSM on fertility and poor reproduction traits in cows fed high amounts of very low-glucosinolate rapeseed meal were reported (Tripathi and Mishra, 2007). Therefore, cows fed diet not only high in Gls RSM but also high in low-glucosinolate RSM are sensitive to dietary glucosinolates. Diets containing Gls may cause thyroid disturbances that depressed fertility (Ahlin et al., 1994), such as increased calving to conception period, more numbers of inseminations per pregnancy and more numbers of acyclic and cystic ovaries (Tripathi and Mishra, 2007). Canola is a trademarked quality description of a group of cultivars of rapeseed variants from which low erucic acid rapeseed oil and low glucosinolate meal are obtained. In the current animal feed market in Iran, canola meal is cheaper than soybean meal (320 vs. 482 Toman/kg; US $1=933 Toman). The objective of this experiment was to evaluate substitution of soybean meal with canola meal and measure its effects on follicular dynamic and days postpartum to first ovulation in early lactation Iranian Holstein cows.

Selective consumption (sorting) of a diet by lactating dairy cows can cause the cows to ingest a diet that could differ from the diet offered (Leonardi and Armentano, 2003). There are several techniques available to minimize the sorting of diets by dairy cows including addition of water to the diet or applying appropriate forage processing. The objective of this experiment was to understand if particle size and dry matter (DM) content of the diet affected health and performance of dairy cows.

Rumen protected fats are often included in dairy cow rations in order to increase the energy density of the ration without compromising rumen function. Various studies have examined the effects of protected fats, with some studies reporting an improvement in various fertility parameters (McNamara et al., 2003). This study examined the effect of feeding protected fat (Megalac™) on production parameters, and on the reproductive performance of high-yielding Holstein-Friesian dairy cattle.

An increase in the input costs in the dairy industry has demonstrated the need for methods to increase production efficiency. One way of increasing efficiency would be to increase the bioavailability of nutrients in a feed stuff, which might be accomplished through the direct feeding of enzymes (Yang et al. 1999). The use of enzymes as additives in ruminant diets has received considerable research interest recently following positive responses observed in feeding trials (Lewis et al. 1995; Beauchemin and Rode, 1996). The objective of present study was to determine the effects of an enzyme mixture (Natuzyme, Bioproton Pty Ltd, Australia) on dairy cow performance.

The minimum amount of dietary NDF needed by a cow is largely based on ruminal and animal health (NRC, 2001). On average, NDF is less digestible than non-fibre carbohydrates (NFC, NRC, 2001). Therefore, NDF concentration is negatively correlated with energy concentration. The NDF is related to ruminal pH, fat percentage, and chewing activity (NRC, 2001). Fat is commonly added to diets of high yielding dairy cows to increase energy density. However, the addition of fat can interfere with rumen fermentation which can result in decreased fibre digestion. Fibre characteristics of the diet may influence the extent to which fats interfere with rumen fermentation. Therefore, the type of fibre influenced the degree of negative effects caused by ruminally active fats (Tackett et al, 1996). The main aim of the present research was to evaluate the effect of supplemental fat and NDF on fibre digestibility, rumen pH and chewing activity in lactating dairy cows.

The European Union Nitrates Directive stipulates mandatory measures that must be included in national action programmes, one of which involves a limit on the amount of livestock manure which may be applied to land each year, set at 170 kg organic nitrogen (manure N) per hectare. This limit will have very significant implications for stocking rates on intensive livestock farms. Consequently, there is increasing interest in developing mitigation strategies to reduce N output in faeces and urine in animal production The objectives of the present study were to evaluate the effects of cross-breeding of Holstein cows with Jersey sires on the efficiency of N utilisation and manure N output.

There is increasing environmental pressure to reduce phosphorus (P) inputs to agricultural systems, including dairy systems. In a recent study (Ferris et al., 2007) dairy cow performance (milk yield, milk composition, food intake and fertility) was found to be unaffected when dairy cows were offered diets containing reduced levels of dietary phosphorus over a four-year period. However, if cows are offered diets containing inadequate dietary P levels for an extended period, bone P reserves may become depleted. The aim of this experiment was to examine the effect of reducing dietary P level on bone composition. Bone samples were collected from cows culled/removed from the study described by Ferris et al. (2007).

Management at calving plays an important role in the subsequent reproductive performance of dairy cows. Postpartum involution in cows, for example, can be impaired by infectious microorganisms ascending into the uterus via the vagina, usually as a result of poor hygiene at parturition or insemination, aided by immune suppression or tissue damage. Susceptible cows are usually those which have suffered previously from dystocia, retained placenta, twin birth, stillbirth or metabolic disorder (Kim and Kang, 2003). The aim of this study was to assess the predisposing factors leading to uterine infection in dairy cows and evaluate its impact on the cow’s performance.

Twinning in dairy cows is looked upon as undesirable, due to management issues and resulting health problems. Continued increases in milk production over the last two decades in dairy herds has been associated with an increase in twinning rate (Wiltbank et al. 2000). The lactation number and level of milk production of the cow appear to be positively associated with increased ovulation rate and twinning (Wiltbank et al. 2000). Unfortunately, twinning is difficult to control by selection due to its association with milk yield and its low heritability (Komisarek and Dorynek, 2002). The aim of this study was to assess the effect of bearing twins on the health and performance of dairy cows.