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The current investigation was carried out to record the final stages of the development of both middle and distal parts of quail ceca, Coturnix coturnix japonica to understand the role of ceca in digestion, immune system, and absorption. The cellular and subcellular structures, including epithelial cell height, microvillus surface area, the proportion of goblet cells, the thickness of muscle layer, and cecum diameter showed great variations during the development. An undeveloped smooth muscularis mucosa was observed for the first time on the ED5. Primordia of glands were observed on the ED7. On the ED15, the middle part exhibited two shapes of mucosal villi: tongue-shaped villi and U-shaped. The plicae and crypts of Lieberkühn were demonstrated on the hatching day. The lymphatic tissues appeared in the wall of both parts of the ceca at the 4 weeks of age. Scanning electron microscopy revealed a great difference in the mucosal surface between different regions. Telocytes were observed in-between the muscle fibers and formed a network during the post-hatching period. Because of fermentation and other bacterial or chemical processes that have been shown to occur in the ceca, this study supports two hypotheses: the cecal development is related to diet and the cecal epithelium act as a site for primary absorption of nutrients or for re-absorption of electrolytes or amino acids derived from the urine.
To investigate a Middle East respiratory syndrome coronavirus (MERS-CoV) outbreak event involving multiple healthcare facilities in Riyadh, Saudi Arabia; to characterize transmission; and to explore infection control implications.
Cases presented in 4 healthcare facilities in Riyadh, Saudi Arabia: a tertiary-care hospital, a specialty pulmonary hospital, an outpatient clinic, and an outpatient dialysis unit.
Contact tracing and testing were performed following reports of cases at 2 hospitals. Laboratory results were confirmed by real-time reverse transcription polymerase chain reaction (rRT-PCR) and/or genome sequencing. We assessed exposures and determined seropositivity among available healthcare personnel (HCP) cases and HCP contacts of cases.
In total, 48 cases were identified, involving patients, HCP, and family members across 2 hospitals, an outpatient clinic, and a dialysis clinic. At each hospital, transmission was linked to a unique index case. Moreover, 4 cases were associated with superspreading events (any interaction where a case patient transmitted to ≥5 subsequent case patients). All 4 of these patients were severely ill, were initially not recognized as MERS-CoV cases, and subsequently died. Genomic sequences clustered separately, suggesting 2 distinct outbreaks. Overall, 4 (24%) of 17 HCP cases and 3 (3%) of 114 HCP contacts of cases were seropositive.
We describe 2 distinct healthcare-associated outbreaks, each initiated by a unique index case and characterized by multiple superspreading events. Delays in recognition and in subsequent implementation of control measures contributed to secondary transmission. Prompt contact tracing, repeated testing, HCP furloughing, and implementation of recommended transmission-based precautions for suspected cases ultimately halted transmission.
The objectives of the current study were to investigate the dynamics of body calcium (Ca) and to estimate the net Ca maintenance requirements (NCam) of Saanen goats, using 45Ca as a radiotracer. Eighteen castrated male Saanen goats (25 ± 2.3 kg body weight (BW)) received a basal diet (ground ear maize, ground maize and vitamin–mineral premix). The treatments consisted of adding limestone to the basal diet to provide Ca content of 0.6, 1.7 and 3.0 g/kg dry matter (DM). The experiment lasted 45 days (i.e. 36 d of adaptation and 9 days of measurements). On day 38, 0.5 ml of 7.4 MBq 45Ca solution was administrated before feeding. From days 39 to 45, samples of faeces, blood and urine were collected, and Ca concentration determined. The Ca intake, Ca in faeces, Ca in urine, faecal endogenous Ca and true absorbed Ca increased linearly as Ca content in the diets increased, while retained Ca increased at a decreasing rate. Dry matter intake decreased at an increasing rate with increased Ca content in the diets. In contrast, Ca content in the diets did not affect biological availability of Ca, or Ca in plasma. The true biological availability of Ca from limestone in Saanen goats was 0.72. The daily NCam was 11.6 (±1.3) mg/kg BW. The current results might help to understand Ca dynamics in goats and enhance the formulation of balanced diets to best meet Ca requirements of Saanen goats.
Sugar cane bagasse is produced in large quantities in Brazil. The cultivated area of sugar cane in recent years has been around 4.2 X 106 ha/year, with a production of about 270 X 106 t/year of cane. As each tonne of cane produces around 300 kg of bagasse by-product, a large quantity of bagasse is generated.
Bagasse is of low dry matter (DM) digestibility (about 250 g/kg), because of lignification. Efforts have been made to improve the digestibility of bagasse using treatment with chemicals (sodium hydroxide, ammonia) or steam (Abdalla et al., 1990). Although steam and pressure treatments have improved in situ degradability, intake and digestibility in cattle were disappointing (Mello et al, 1989). Recently treatment of bagasse with irradiation and ammonia have been investigated.
At maintenance at least, the whole tract digestibility of several foods in sheep and cattle is similar, consequently much of the information on the nutritive value of dairy cow foods in food composition tables is derived from studies conducted in sheep. However, Adesogan (1996) reported that in whole-crop wheat (WCW), starch digestibility is higher in sheep than in dairy cows. This study examined the validity of using sheep to model the ruminal degradation of WCW in cows by comparing the degradability of dry matter (DM) and nitrogen (N) of urea-treated WCW in both species.
Winter wheat (cv. Hussar) was harvested at 540 g DM per kg and conserved following urea application at target rates of 20 or 40g/kg DM (WCW2 and WCW4 respectively). The degradability of the forages was examined in dairy cows given 6 kg dairy concentrate and grass silage ad libitum and in wethers given 2.4 kg/day of grass silage supplemented with 0.36kg/day of rolled, mineralized barley.
The in vitro gas production is a widely used technique for the evaluation of feeds for ruminant animals. Although it measures rate and extension of gas production during feed fermentation in culture medium, rumen inoculum from operated animals (fistulae) is required. Faecal microorganisms function similarly to those in the rumen; they decompose feed and do not require operated animals. The objective of the present experiment was to compare rumen liquor and equine faeces as source of inoculum in the gas production technique.
The over-dependency and misuse of the chemotherapeutic drugs available to parasite control with consequent development of anthelmintic resistance, mainly in small ruminants, has been demanded alternative sources to control gastrointestinal nematodes in sheep. The aim of the present study was to investigate the potential anthelmintic effects of condensed tannins (CT) from acacia extract (AE) on Trichostrongylus colubriformis in experimentally infected sheep.
Cooperia punctata is the most prevalent parasitic intestinal nematode in Brazil and its site of fixation is duodenum and jejunum that are also the sites of greatest dietary phosphorus (P) absorption. Studies of phosphorus metabolism often involves balance trials and use of isotopes. When combined with mathematical modeling, calculation of flows between several pools becomes a possibility. The objective of the study on calves employing isotope and balance techniques was to apply and compare two models of P metabolism for resolving data generated by these techniques.
The phenolic compounds are substances which reduce feed intake, protein digestibility and reduce ruminal activity in sheep and goats. To reduce the effects of tannins a lot of synthetic materials, for example PEG (polyethylene glycol) is tested as tannin-binding agent, and let protein free for the digestibility. The aim of this work was to test the effect of tannins in the rumen microbial growth using the in vitro 32P incorporation technique.
Clinical and sub clinical parasite infection depresses live-weight gain, feed intake, milk and wool production and can impair soft tissue deposition and skeletal growth. To date these infections have been controlled using anthelmintics, however the increasing prevalence of multiple anthelmintic resistance points towards the urgent need for alternative methods to reduce our reliance upon chemoprophylaxis. In addition, the worldwide growth of organic agriculture, in which the use of synthetic products is strongly restricted, needs alternatives for helminthes control. The aim of this experiment was to evaluate the effect of dietary condensed tannins (CT) on Haemonchus contortus infection in sheep.
Cooperia punctata is the most prevalent intestinal parasite in young bovines in Brazil (Lima, 1998). The site of fixation of C. punctata is the upper part of the small intestine (Bailey, 1949), also the site of dietary phosphorus (P) absorption (Schröder et al, 1995), and the damage caused in the intestinal epithelium could interfere with P metabolism (Bown et al, 1989). The aim of the present experiment was to evaluate the P kinetics by using 32P isotopic dilution technique in calves submitted to single and trickle infection by C. punctata.
Ruminant feeding standards in Brazil are generally based on systems developed for temperate regions and there is a serious lack of information on grazed tropical pasture which is the main feedstuff. Signal grass (Brachiaria decumbens) represents half of the total cultivated pastures in Brazil (Miles et al., 1996). This study investigated the intake and digestibility by sheep of signal grass hay cut after re-growths of 28 and 56 days to represent the range used in practice in the Brazilian savanna. Lucerne hay was included as a positive control. The hays were offered at two levels of intake to Santa Ines wether sheep.
Phosphorus and calcium deficiency in horses represents an important factor responsible for the low equine production in Brazil. The basic mechanisms of P and Ca metabolism differ substantially among species. Regulation of P and Ca metabolism is less well understood in horses than in others species. With the use of the isotopic dilution technique is possible to evaluate the metabolism for this mineral. The aim of the present experiment was to study the effect of different Ca levels in the diet on P and Ca metabolism in horses.
In vitro and in situ techniques for research on ruminants are currently much in focus. Since they have good correlations with in vivo data, they are feasible alternatives to predict the nutrition rates of feeds and may be applied in equine research on in vivo apparent digestibility. On the other hand, the disadvantage of these methods is due to the fact that fistulated animals are required to obtain the inoculum. Theodorou et al., (1994) developed an extremely promising gas production technique to assess feeds for ruminants, but still require rumen inoculum obtained from operated animals. Faecal microorganisms function similarly to those in the rumen and in the large intestine of equines. The objective this experiment was to compare rumen liquor and equine faeces as inoculum to determine in vitro digestibility of equine feeds.
Some herbaceous browses have shown a dry tolerance and had been used as animal feed. However, some of those plants have anti nutritional compounds such as tannins that can interfere on intake and digestibility. Tannins are polyphenolic compounds originated from the secondary metabolism of the plant as protection against insects, birds and as a result of drought, temperature or soil fertility. The objectives of this work were to evaluate the level and variation of tannins in important browses from the semi-arid of Brazil and to investigate the effects of different treatments (oven-, shade- and sun-drying and treatment with urea) on phenolics compounds.
The use of leguminous forages is an alternative of protein supplementation in animal diets. Leucaena leucocephala (leucaena) is lifelong leguminous forage that can be directly grazed or harvested, offered fresh, hay or silage to animals. Many leguminous show anti-nutritional factors that may reduce the use of these plants in animal diets. Condensed tannin (CT) is one common anti-nutritional factor present in the leucaena. The objective of this work was to evaluate the use of Leucaena leucocephala in Santa Inês sheep diets on intake and digestibility parameters.
Parasitic intestinal infections can affect the health of calves inducing symptoms like loss of appetite, diarrhoea, nutritional deficiency, loss of protein, and reduced weight gain. Cooperia punctata is the most prevalent parasitic intestinal nematode in Brazil (Lima, 1998) and its site of fixation is the upper part of the small intestine, i.e., duodenum and jejunum (Bailey, 1949) that are also the sites of greatest dietary phosphorus absorption (Schröder et al., 1995). Thus, the damage caused by the parasite when it penetrates the intestinal epithelium can interfere with phosphorus metabolism. The objective of this experiment was to evaluate the true phosphorus absorption by calves submitted to an acute infection with C. punctata using the 32P isotopic dilution technique.
Brazil has arid regions where livestock production is limited by forage source. However, some native herbaceous legumes have a dry tolerance and had been used as animal feed. Some of those plants have anti nutritional compounds such as tannins that and can interfere on intake and digestibility of these plants. Tannins have a high affinity with proteins and could make these molecules unavailable for animal. Compounds as polyvinylpolypyrrolidone (PVPP) have been used on tannin studies, because it has more affinity with tannins than proteins. Based on that, it is possible to evaluate the nutritive potential of tanniniferous plants, using PVPP as an inhibitor of tannin effects. The aim of this work was to evaluate the effect of tannins on in vitro rumen fermentation.
In a previous study in Reading (altitude 66 m) (Mauricio et al., 1997) the lag phase was greater when cow faeces was used as a source of microorganisms in the in vitro gas production technique instead of rumen liquor when twelve temperate forages were fermented for 96 h. In the Reading study faeces and rumen liquor were obtained from a cow fed grass silage and concentrate (60:40). The present study was done in Piracicaba, Brazil-BR (altitude 780 m) which has a tropical climate. Using the same forages as in Mauricio et al. (1998), the study examined whether the same differences between faeces and rumen liquor would occur in a tropical environment. In addition, the opportunity was taken to develop an equation relating pressure and volume for the semi-automated pressure transducer technique and compare it with the equation developed in UK by Mauricio et al. (1998).