Background： Dorper is an important breed for meat purpose and widely used in the livestock industry of the world.However, the protein requirement of Dorper crossbred has not been investigated. The current paper repor...Background： Dorper is an important breed for meat purpose and widely used in the livestock industry of the world.However, the protein requirement of Dorper crossbred has not been investigated. The current paper reports the net protein（NP） and metabolizable protein（MP） requirements of Dorper crossbred ram lambs from 20 to 35 kg BW.Methods： Thirty-five Dorper × thin-tailed Han crossbred lambs weaned at approximately 50 d of age（20.3 ± 2.15 kg of BW） were used. Seven lambs of 25 kg BW were slaughtered as the baseline animals at the start of the trial. An intermediate group of seven randomly selected lambs fed ad libitum was slaughtered at 28.6 kg BW. The remaining 21 lambs were randomly divided into three levels of dry matter intake： ad libitum or 70% or 40% of ad libitum intake. Those lambs were slaughtered when the lambs fed ad libitum reached 35 kg BW. Total body N and N retention were measured.Results： The daily NP and MP requirements for maintenance were 1.89 and 4.52 g/kg metabolic shrunk BW（SBW0.75）.The partial efficiency of MP utilization for maintenance was 0.42. The NP requirement for growth ranged from 12.1 to 43.5 g/d, for the lambs gaining 100 to 350 g/d, and the partial efficiency of MP utilization for growth was 0.86.Conclusions： The NP and MP requirements for the maintenance and growth of Dorper crossbred male lambs were lower than the recommendations of American and British nutritional systems.展开更多
A trial on Acacia albida leaf supplementation on reproductive parameters and pre-weaning growth of Arabian lambs was conducted from September 2020 to May 2021 at the small ruminant station of the Livestock Research In...A trial on Acacia albida leaf supplementation on reproductive parameters and pre-weaning growth of Arabian lambs was conducted from September 2020 to May 2021 at the small ruminant station of the Livestock Research Institute for Development (IRED) in N’Djamena, Chad. Forty-eight (48) Arabian sheep (45 non-pregnant females and 3 males for a sex ratio of 1 ram to 15 ewes) with an average weight of 20.3 ± 1.2 kg and aged approximately 2 years were divided into 3 groups of 15 ewes each. The supplemented group received in addition to the dominant forage of the pasture (300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum), 400 g and 600 g of Acacia albida leaves/animal/day while the control group received only 300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum. From the results of this study, it appears that the ewes that received 400 g of Acacia albida leaves had a significantly higher fertility rate and birth mortality rate (93.03% and 6.25% respectively). Animals in the control group had a significantly higher pre-weaning mortality rate than those receiving Acacia albida leaves as a supplement (16.66% versus 6.66% and 14.28% respectively). The highest weight of the lambs was observed in the ration supplemented with 600 g of Acacia albida leaves (12209.66 g). The total weight gain, as well as the average daily weight gain of the lambs receiving the 600 g Acacia albida leaf ration was significantly higher than those of the other rations. Supplementation with 400 g and 600 g of Acacia albida leaves can be recommended as a protein supplement for breeding ewes and pre-weaned lambs.展开更多
The objective of current study was to determine the effect of different ratios of pomegranate peel in diets of Karadi lambs (0%, 1%, 2% or 4% as control, T1, T2 and T3, respectively) on body weight, total body gain, a...The objective of current study was to determine the effect of different ratios of pomegranate peel in diets of Karadi lambs (0%, 1%, 2% or 4% as control, T1, T2 and T3, respectively) on body weight, total body gain, average daily gain, daily feed intake and apparent digestibility of nutrients. Sixteen Karadi male lambs weighing 23.29 ± 0.42 kg and 4.5-5 months old randomly divided into equally four treatment groups and individually penned for the period of 63 days. Results indicated that final body weight was significantly (P < 0.05) higher in lambs fed 1% or 2% pomegranate peel (PP) as compared to lambs fed 4% PP. The best improvements in total feed intake, total gain, average daily gain and feed conversion ratio (FCR) in lambs fed 1% PP. The total dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), ash, nitrogen free extract (NFE) and metabolizable energy (ME) intake per (body weight<sup>0.75</sup>) increased (P < 0.05) significantly in lambs fed 1% pomegranate peel (PP);however, the crude fiber (CF) intake decreased in lambs fed 1% PP as compared to other treatments. While, the dry matter digestibility (DMD), crude protein digestibility (CPD), crude fiber digestibility (CFD) and nitrogen free extract digestibility (NFED) were significantly (P < 0.05) higher in lambs fed 1% PP as compared to T2, T3 and control groups. In addition, EED increased significantly in T3 compared to other treatments. In conclusion, it was indicated that addition of pomegranate peel in diet at the rate of 1% or 2% had significant effect on Karadi lambs performance and digestibility.展开更多
The net protein （NP） and metabolizable protein （MP） requirements of Dorper crossbred female lambs from 20 to 35 kg body weight （BW） were assessed in a comparative slaughter trial. Thirty-five Dorper×thin-ta...The net protein （NP） and metabolizable protein （MP） requirements of Dorper crossbred female lambs from 20 to 35 kg body weight （BW） were assessed in a comparative slaughter trial. Thirty-five Dorper×thin-tailed Hart crossbred lambs weaned at approximately 50 d of age （（19.1±2.37） kg of BW） were used. Seven randomly selected lambs were slaughtered at the beginning of the trial as baseline group （BL）. An intermediate group of seven randomly selected lambs fed ad libitum （AL） intake was slaughtered when the lambs reached an average BW of 28.6 kg. The remaining 21 lambs were allotted randomly to three levels of dry matter intake： AL or restricted to 70 or 40% of the AL intake. All lambs were slaughtered when the sheep fed AL intake reached 35 kg of BW. Total body N and N retention were determined. The results showed that the maintenance requirements for NP and MP were 1.75 and 3,37 g kg^-1 metabolic shrunk body weight （SBW^0.75）, respectively. The partial efficiency of protein use for maintenance was 0.52. The NP requirements for growth ranged from 10.9 to 42.4 g d^-1 for the lambs gaining 100 to 350 g d^-1 from 20 to 35 kg BW. The partial efficiency of MP for growth was 0.52. In conclusion, the NP and MP requirements for the maintenance and growth of Dorper crossbred female lambs were lower than those reported by AFRC （1993） and NRC （2007） recommendations.展开更多
[ Objective] To provide a reference for understand effects of acidifiers on digestibility of lambs. [Method] Feeding experiment as well as digestion and metabolism experiment was conducted to evaluate effects of suppl...[ Objective] To provide a reference for understand effects of acidifiers on digestibility of lambs. [Method] Feeding experiment as well as digestion and metabolism experiment was conducted to evaluate effects of supplementing acidifiers on ultra-early weaned lambs. [ Result] Diets of ultra-early weaned lambs supplemented with acidifiers greatly improved their production performance and increased digestibility of feed. However, different acidifier products had certainly various effects on lambs. Acidifier product I increased weight gain, feed conversion ratio and apparent di- gestibility of main nutrients more greatly than acidifier product II did, while the result was contrary in reducing diarrhea incidence. [ Conclusion] Whether the acidifiers can increase digestibility of nutrients or not is still uncertain and needs further studies.展开更多
The effects of sulfur dioxide(SO_2) on the dry weight growth gas exchange rate and leaf sulfur content of massion pine(Pinus massoniana Lamb. )were investigated. The results obtained in this study show that the dry we...The effects of sulfur dioxide(SO_2) on the dry weight growth gas exchange rate and leaf sulfur content of massion pine(Pinus massoniana Lamb. )were investigated. The results obtained in this study show that the dry weight growth and net photosynthetic rate of masson pine seedlings are reduced by exposure to SO_2 at ≥100 ppb. From these results,one of the main causes in the dieback of masson pine forest reported in Chongqing,China may be relatively high concentrations of atmospheric SO_2 in the relevant area.展开更多
基金supported by the earmarked fund for the China Agriculture Research System(CARS-39)
文摘Background： Dorper is an important breed for meat purpose and widely used in the livestock industry of the world.However, the protein requirement of Dorper crossbred has not been investigated. The current paper reports the net protein（NP） and metabolizable protein（MP） requirements of Dorper crossbred ram lambs from 20 to 35 kg BW.Methods： Thirty-five Dorper × thin-tailed Han crossbred lambs weaned at approximately 50 d of age（20.3 ± 2.15 kg of BW） were used. Seven lambs of 25 kg BW were slaughtered as the baseline animals at the start of the trial. An intermediate group of seven randomly selected lambs fed ad libitum was slaughtered at 28.6 kg BW. The remaining 21 lambs were randomly divided into three levels of dry matter intake： ad libitum or 70% or 40% of ad libitum intake. Those lambs were slaughtered when the lambs fed ad libitum reached 35 kg BW. Total body N and N retention were measured.Results： The daily NP and MP requirements for maintenance were 1.89 and 4.52 g/kg metabolic shrunk BW（SBW0.75）.The partial efficiency of MP utilization for maintenance was 0.42. The NP requirement for growth ranged from 12.1 to 43.5 g/d, for the lambs gaining 100 to 350 g/d, and the partial efficiency of MP utilization for growth was 0.86.Conclusions： The NP and MP requirements for the maintenance and growth of Dorper crossbred male lambs were lower than the recommendations of American and British nutritional systems.
文摘A trial on Acacia albida leaf supplementation on reproductive parameters and pre-weaning growth of Arabian lambs was conducted from September 2020 to May 2021 at the small ruminant station of the Livestock Research Institute for Development (IRED) in N’Djamena, Chad. Forty-eight (48) Arabian sheep (45 non-pregnant females and 3 males for a sex ratio of 1 ram to 15 ewes) with an average weight of 20.3 ± 1.2 kg and aged approximately 2 years were divided into 3 groups of 15 ewes each. The supplemented group received in addition to the dominant forage of the pasture (300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum), 400 g and 600 g of Acacia albida leaves/animal/day while the control group received only 300 g of Dactyloctenium aegyptium + 300 g of Cenchrus ciliaris + 600 g of Panicum maximum. From the results of this study, it appears that the ewes that received 400 g of Acacia albida leaves had a significantly higher fertility rate and birth mortality rate (93.03% and 6.25% respectively). Animals in the control group had a significantly higher pre-weaning mortality rate than those receiving Acacia albida leaves as a supplement (16.66% versus 6.66% and 14.28% respectively). The highest weight of the lambs was observed in the ration supplemented with 600 g of Acacia albida leaves (12209.66 g). The total weight gain, as well as the average daily weight gain of the lambs receiving the 600 g Acacia albida leaf ration was significantly higher than those of the other rations. Supplementation with 400 g and 600 g of Acacia albida leaves can be recommended as a protein supplement for breeding ewes and pre-weaned lambs.
文摘The objective of current study was to determine the effect of different ratios of pomegranate peel in diets of Karadi lambs (0%, 1%, 2% or 4% as control, T1, T2 and T3, respectively) on body weight, total body gain, average daily gain, daily feed intake and apparent digestibility of nutrients. Sixteen Karadi male lambs weighing 23.29 ± 0.42 kg and 4.5-5 months old randomly divided into equally four treatment groups and individually penned for the period of 63 days. Results indicated that final body weight was significantly (P < 0.05) higher in lambs fed 1% or 2% pomegranate peel (PP) as compared to lambs fed 4% PP. The best improvements in total feed intake, total gain, average daily gain and feed conversion ratio (FCR) in lambs fed 1% PP. The total dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), ash, nitrogen free extract (NFE) and metabolizable energy (ME) intake per (body weight<sup>0.75</sup>) increased (P < 0.05) significantly in lambs fed 1% pomegranate peel (PP);however, the crude fiber (CF) intake decreased in lambs fed 1% PP as compared to other treatments. While, the dry matter digestibility (DMD), crude protein digestibility (CPD), crude fiber digestibility (CFD) and nitrogen free extract digestibility (NFED) were significantly (P < 0.05) higher in lambs fed 1% PP as compared to T2, T3 and control groups. In addition, EED increased significantly in T3 compared to other treatments. In conclusion, it was indicated that addition of pomegranate peel in diet at the rate of 1% or 2% had significant effect on Karadi lambs performance and digestibility.
基金supported by the earmarked fund for the China Agriculture Research System (CARS-39)
文摘The net protein （NP） and metabolizable protein （MP） requirements of Dorper crossbred female lambs from 20 to 35 kg body weight （BW） were assessed in a comparative slaughter trial. Thirty-five Dorper×thin-tailed Hart crossbred lambs weaned at approximately 50 d of age （（19.1±2.37） kg of BW） were used. Seven randomly selected lambs were slaughtered at the beginning of the trial as baseline group （BL）. An intermediate group of seven randomly selected lambs fed ad libitum （AL） intake was slaughtered when the lambs reached an average BW of 28.6 kg. The remaining 21 lambs were allotted randomly to three levels of dry matter intake： AL or restricted to 70 or 40% of the AL intake. All lambs were slaughtered when the sheep fed AL intake reached 35 kg of BW. Total body N and N retention were determined. The results showed that the maintenance requirements for NP and MP were 1.75 and 3,37 g kg^-1 metabolic shrunk body weight （SBW^0.75）, respectively. The partial efficiency of protein use for maintenance was 0.52. The NP requirements for growth ranged from 10.9 to 42.4 g d^-1 for the lambs gaining 100 to 350 g d^-1 from 20 to 35 kg BW. The partial efficiency of MP for growth was 0.52. In conclusion, the NP and MP requirements for the maintenance and growth of Dorper crossbred female lambs were lower than those reported by AFRC （1993） and NRC （2007） recommendations.
基金supported by Research,Demonstration and Popularization of Breeding and Breeding Techniques of the Tan Sheep in Ningxia Hui Autonomous Region
文摘[ Objective] To provide a reference for understand effects of acidifiers on digestibility of lambs. [Method] Feeding experiment as well as digestion and metabolism experiment was conducted to evaluate effects of supplementing acidifiers on ultra-early weaned lambs. [ Result] Diets of ultra-early weaned lambs supplemented with acidifiers greatly improved their production performance and increased digestibility of feed. However, different acidifier products had certainly various effects on lambs. Acidifier product I increased weight gain, feed conversion ratio and apparent di- gestibility of main nutrients more greatly than acidifier product II did, while the result was contrary in reducing diarrhea incidence. [ Conclusion] Whether the acidifiers can increase digestibility of nutrients or not is still uncertain and needs further studies.
文摘The effects of sulfur dioxide(SO_2) on the dry weight growth gas exchange rate and leaf sulfur content of massion pine(Pinus massoniana Lamb. )were investigated. The results obtained in this study show that the dry weight growth and net photosynthetic rate of masson pine seedlings are reduced by exposure to SO_2 at ≥100 ppb. From these results,one of the main causes in the dieback of masson pine forest reported in Chongqing,China may be relatively high concentrations of atmospheric SO_2 in the relevant area.
