Emad M. Samara

Nutritional value of green seaweed (Ulva lactuca) for broiler chickens

The current work aimed to assess the potential of the green seaweed Ulva lactuca (U. lactuca) as an alternative ingredient in broiler chicken diets. The effect of substituting 1.0 or 3.0% of corn with U. lactuca on performance, carcass characteristics and serum constituents of broilers from 12 to 33 d of age was evaluated. Three treatments were distributed in a RCBD design: T1, control diet (0% U. lactuca); T2, 1.0 % U. lactuca; T3, 3.0 % U. lactuca. A total of 45 chicks were assigned to three treatments (5 replicates per treatment) used in this experiment. Cumulative feed intake (FI), body weight gain (BWG), feed conversion ratio (FCR) and nutrients retention from 12 to 33 d of age were not affected by treatment (P>0.05). Birds which had received T3 had a higher dressing percentage and breast muscle yield compared to those which had received T1 or T2. Serum total lipid, cholesterol and uric acid concentrations were significantly lower in birds which had received T2 and T3 (P<0.05). Serum enzymes and electrolytes were not influenced by any dietary treatment except for alanine transaminase (ALT) which was significantly lower for the treated groups. Based on presented evidences, it is recommended to substitute 3.0% of corn with green seaweed (U. lactuca).

Impacts of Stocking Density on the Performance and Welfare of Broiler Chickens

The current study was performed to investigate the influence of different stocking density rates on the performance, thermophysiological measurements as well as blood parameters of 0 to 30 d of age female Ross broiler. A total of 96 chicks were randomly distributed in a randomized complete block design among 12 cages. Three stocking density rates were applied; low (28.0 kg/m2), medium (37.0 kg/m2) and high (40.0 kg/m2). Results revealed that cumulative body weight gain (BWG) and feed intake (FI) were influenced (P<0.01) by the rate of stocking density, while no effect (P>0.05) were observed for broilers mortalitycorrected feed conversion ratio (FCR). Higher BWG (P<0.01) and FI (P<0.05) were reported for low and medium density rates broilers in comparison to the high density rate broilers. Overall means of body temperature as well as head, neck, wing, body and shank surface temperatures have displayed (P<0.05) higher values in medium and high density rates broilers compared to the low density rate broilers. Furthermore, increasing the stocking density from 28 to 40 kg/m2 induced a state of hemodilution in higher density rate broilers, which might explain the noticeable decrease in packed cell volume (PCV). Meanwhile, an increase in serum aspartate aminotransferase (AST) was observed in the higher density group, which might indicate hepatocellular injures. It can be concluded that increasing the stocking density rate from 28 to 40 kg of BW/m2 had evident impingement effects on the performance of broiler chicken and could jeopardize their welfare.

Concerns about Misinterpretation of Recent Scientific Data Implicating Dromedary Camels in Epidemiology of Middle East Respiratory Syndrome (MERS)

This letter addresses some concerns about two recent articles published by the same authors in mBio (1, 2), specifically many uncertainties regarding the potential applicability of their epidemiological data, which were obtained from dromedary camels (DCs) infected with Middle East respiratory syndrome coronavirus (MERS-CoV), to human public health. Aiming to investigate the possible role of DCs in the transmission of MERS-CoV to humans, the authors in their first article determined the seroprevalence of MERS-CoV infection in DCs throughout Saudi Arabia and arrived at three main conclusions (1). Their first conclusion was that DCs can be infected with MERS-CoV, as evident by the determination of (i) high loads of viral nucleic acids (RNA) and antibodies to MERS-CoV in archived and freshly collected samples and (ii) a high resemblance (>99%) in the collected samples in three regions of phylogenetically analyzed MERS-CoV genomic sequence. Their second conclusion is that there are seroprevalence differences in MERS-CoV infection depending on the camel’s age (95% of the adults compared to 35% of the juveniles) and the region of the country (ranging from 90% in the East to 5% in the Southwest). The third conclusion is that airborne transmission is the main mode of MERS-CoV transmission, as evidenced by the more frequent detection of viral nucleic acids in nasal swabs than in rectal specimens. Furthermore, the authors in their second article described complete genomic sequencing of MERS-CoV isolated from both DCs and humans and arrived at two more conclusions (2). First, they demonstrated that DCs can be simultaneously infected with three genetic variants (genotypes) of MERS-CoV; second, they showed that the alignment of the complete genomic sequence of one MERS-CoV genotype (claimed to be a quasispecies) obtained from culturing the virus from nasal swab samples of DCs was indistinguishable from the genomic sequence of MERS-CoV recovered …

Effects of dietary seaweed (Ulva lactuca) supplementation on the reproductive performance of buck and doe rabbits

The aim of this study was to investigate the effect of dietary supplementation of seaweed on the reproductive performance of rabbits. Two trials were performed during this study. In the first trial, semen quality was evaluated in 15 buck rabbits with mean body weight of 4.80±0.41 kg and six month of age. In the second trial, prolificacy was determined in 30 artificially inseminated does with a mean body weight of 4.84±0.50 kg and five to six months of age. Rabbits in each trial were randomly allocated to one of three dietary seaweed levels; commercial pelleted diet (C), pelleted diet supplemented with 1% seaweed (T1), and pelleted diet supplemented with 2% seaweed (T2). Dietary supplementation of seaweed significantly increased plasma testosterone concentration and improved various sperm motility parameters. Analysis of acrosomal membrane integrity using electron microscopy revealed no significant influences of dietary seaweed supplementation on quality grade (I–IV) of all tested samples. These results reflected in positive prolificacy response of does artificially inseminated with semen samples pooled from bucks fed on T2, and offered diet supplemented with 2% seaweed one week prior to their insemination and throughout the gestation period. Feeding diets supplemented with 2% seaweed to doe rabbits improved their kindling rate, litter size, and their offspring ratio. Seaweed supplementation to the diets of rabbits raised under summer conditions had improved their reproductive performance by improving the semen fertility characteristics of bucks and the prolificacy characteristics of does. Hematological and biochemical parameters investigated in this study did not reveal any pathological signs in both rabbits genders due to dietary seaweed supplementation.

Regional and circadian variations of sweating rate and body surface temperature in camels (Camelus dromedarius).

It was the aim of this study to investigate the regional variations in surface temperature and sweating rate and to visualize body thermal windows responsible for the dissipation of excess body heat in dromedary camels. This study was conducted on five dromedary camels with mean body weight of 450 ± 20.5 kg and 2 years of age. Sweating rate, skin and body surface temperature showed significant (P < 0.001) circadian variation together with the variation in ambient temperature. However, daily mean values of sweating rate, skin and body surface temperature measured on seven regions of the camel body did not significantly differ. The variation in body surface temperature compared to the variation in skin temperature was higher in the hump compared to the axillary and flank regions, indicating the significance of camels fur in protecting the skin from daily variation in ambient temperature. Infrared thermography revealed that flank and axillary regions had lower thermal gradients at higher ambient temperature (T(a) ) and higher thermal gradients at lower T(a) , which might indicate the working of flank and axillary regions as thermal windows dissipating heat during the night. Sweating rate showed moderate correlation to skin and body surface temperatures, which might indicate their working as potential thermal drivers of sweating in camels.

Influence of introducing machine milking on biothermal parameters of lactating camels (Camelus dromedarius)

The current study wanted to investigate the physiological suitability of using the machine milking in lactating camels by assessing several biothermal (thermophysiological and infrared thermographical) parameters. These parameters were assessed on 3 consecutive days, immediately before, immediately after, as well as 1 h after machine milking. The sample was composed of 12 multiparous dromedary camels at mid-lactation. The hypothesis of the current study was that introducing machine milking would produce noticeable effects on the physiological status of lactating camels. On the contrary, the obtained results revealed that machine milking had no effect (P>0.05) on average rectal (37.88±0.23°C) and vaginal temperatures (37.94±0.14°C), as well as respiratory (16.12±0.23 breath/min) and heart rates (56.78±1.89 beat/min). A significant decrease (P<0.001) in udder (−1.0°C) and teat (−1.6°C) surface temperatures, instead, was detected 1 h immediately after milking. Accordingly, this study provides a clear evidence that introducing machine milking has no effect on the homeothermic status of lactating camels.

Influence of stocking density on welfare indices of broilers

The current study was conducted to identify the influence of short-term (five days) high stocking density (SD) on broilers’ welfare by assessing several thermophysiological parameters in 32 birds of 43 days of age Ross male broiler chickens. Based on broiler’s body weight, broilers were randomly allotted into two SD rates; control (26.5 kg/m2) or high (45.0 kg/m2). It appears evident that placing broilers at high SD as 45.0 kg/m2had manifested noticeable impacts on their thermophysiological responses. This conclusion was demonstrated by the existence of results of the current study showed a major displacements in broilers’ homeothermic status, high SD broilers experienced pronounced elevations of their body temperatures as well as head, body and shank surface temperatures over the control SD broilers. Additionally, this was further emphasized by the noticeable displacements of body internal, external and total thermal gradients as well as heat loss index of high SD broilers compared to the control broilers. Based on the presented evidences, short-term high SD markedly increased broilers stress and jeopardize their welfare. Measuring broilers’ thermophysiological responses under different rates of SD can be adapted to assess their welfare.

Daily Rhythms of Physiological Parameters in the Dromedary Camel Under Natural and Laboratory Conditions

Camels are well adapted to hot arid environments and can contribute significantly to the economy of developing countries in arid regions of the world. Full understanding of the physiology of camels requires understanding of the internal temporal order of the body, as reflected in daily or circadian rhythms. In the current study, we investigated the daily rhythmicity of 20 physiological variables in camels exposed to natural oscillations of ambient temperature in a desert environment and compared the daily temporal courses of the variables. We also studied the rhythm of core body temperature under experimental conditions with constant ambient temperature in the presence and absence of a light-dark cycle. The obtained results indicated that different physiological variables exhibit different degrees of daily rhythmicity and reach their daily peaks at different times of the day, starting with plasma cholesterol, which peaks 24min after midnight, and ending with plasma calcium, which peaks 3h before midnight. Furthermore, the rhythm of core body temperature persisted in the absence of environmental rhythmicity, thus confirming its endogenous nature. The observed delay in the acrophase of core body temperature rhythm under constant conditions suggests that the circadian period is longer than 24h. Further studies with more refined experimental manipulation of different variables are needed to fully elucidate the causal network of circadian rhythms in dromedary camels.

Correlation of blood triiodothyronine (T3) level with some production traits in male goat kids

Khalid ABDOUN*, Emad SAMARA, Aly OKAB, Mohamed AL-BADWI, Mohamed EL-ZAREI, Ali AL-SEAF, Ahmed AL-HAIDARY Department of Animal Production, College of Food and Agriculture Sciences, King Saud University, Riyadh, Saudi Arabia Department of Environmental Studies, Institute of Graduate Studies and Research, Alexandria University, Alexandria, Egypt Department of Animal Production and Breeding, College of Agriculture and Veterinary Medicine, Qassim University, Qassim, Saudi Arabia