Two experiments were conducted to investigate the efficacy of benzoic acid on the growth performance of nursery and grower-finisher pigs. A randomized complete block design was used in both experiments with the initia...Two experiments were conducted to investigate the efficacy of benzoic acid on the growth performance of nursery and grower-finisher pigs. A randomized complete block design was used in both experiments with the initial body weight as the blocking factor. There were 3 treatments corresponding to 3 dietary levels of benzoic acid: 0, 0.3%, and 0.5%. In experiment 1, a total of 144 PIC L1050 barrows(initial body weight 7.1 ± 0.6 kg) were used with each treatment replicated 8 times. In experiment 2, a total of 288 PIC L1050 barrows(initial body weight 36.1 ± 3.6 kg) were used with each treatment replicated 16 times.There were 6 barrows in each replicate pen for both experiments. Experiments 1 and 2 lasted 28 and 70 days, respectively. In experiment 1, average daily gain(ADG) of all growth phases increased linearly(P < 0.05) with increasing supplementation of benzoic acid, which led to a linear improvement in average body weight on d 28(P < 0.05). There was also an improvement in feed conversion ratio(FCR) of d 0 to 14(linear effect: P < 0.05) and in average daily feed intake(ADFI) of d 14 to 28 and d 0 to 28(linear effect:P < 0.01). In experiment 2, ADG during d 0 to 35 and d 35 to 70 and average body weight on d 35 improved linearly(P < 0.05) with increasing supplementation of benzoic acid. Average daily gain of d 0 to70 and average body weight on d 70 increased significantly in a both linear and quadratic manner. There was a linear improvement in FCR in all growth phases(P < 0.05). In conclusion, the dietary inclusion of benzoic acid at the supplementation levels of 0.3% and 0.5% significantly improved the growth performance of nursery and grower-finisher pigs in the current study; the nursery pigs responded to the dietary supplementation of benzoic acid up to 0.5% linearly while the grower-finisher pigs achieved the optimal ADG at the calculated supplementation level of 0.36%.展开更多
Objective:To investigate the loxic implications of ethanolic stem bark extract of Azadirachta indica(A-indica)at 50,100,200 and 300 mg/kg body weight in Wistar rats.Methods:Fifty male rats of Wistar strains were rando...Objective:To investigate the loxic implications of ethanolic stem bark extract of Azadirachta indica(A-indica)at 50,100,200 and 300 mg/kg body weight in Wistar rats.Methods:Fifty male rats of Wistar strains were randomly grouped into five(A-F.)of ten animals each.Animals in Group A(control)were orally administered 1 mL of distilled water on daily basis for 21 days while those in Groups B-E received same volume of the extract corresponding to 50,100,200 and 300mg/kg body weight.Results:The extract did not significantly(P>0.05)alter the levels of albumin,total protein,red blood cells and factors relating to it whereas the white blood cell,platelets,serum triacylglycerol and high-density lipoprotein cholesterol decreased significantly(P<0.05).In contrast,the final body weights,absolute weights of the liver,kidney,lungs and heart as well as their organ-body weight ratios,serum globulins,total and conjugated bilirubin,serum cholesterol,low-density lipoprotein cholesterol and computed atherogenic index increased significantly.The spleen-body weight ratio,alkaline phosphatase,alanine and aspartate transaminases,sodium,potassium,calcium,feed and water intake were altered at specific doses.Conclusions:Overall,the alterations in the biochemical parameters of toxicity have consequential effects on the normal functioning of the organs of the animals.Therefore,the ethanolic extract of A.indica stem bark at the doses of 50,100,200 and 300 mg/kg body weight may not be completely safe as an oral remedy and should be taken with caution if absolutely necessary.展开更多
Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-t...Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-tryptophan and L-arginine on feed intake and the mRNA expression levels of hypothalamic Neuropeptide involved in feed intake regulation in broiler chicks. Leucine, glutamate, tryptophan or arginine was intra-cerebroventricularly （ICV） administrated to 4d-old broiler chicks respectively and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of Neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotrophin releasing factor （CRF）. Our results showed that ICV administration of L-leucine （0.15 or 1.5 μmol） significantly （P〈0.05） increased feed intake up to 2 h post-administration period and elevated both hypothalamic NPY and AgRP mRNA expression levels. In contrast, ICV administration of L-glutamate （1.6 μmol） significantly （P 〈 0.05） decreased feed intake 0.25, 0.5 and 2 h post-injection, and increased hypothalamic CRF and MC4R mRNA expression levels. Meanwhile, both L-tryptophan （10 or 100 μg） and L-arginine （20 or 200 μg） had no significant effect on feed intake. These findings suggested that L-leucine and L-glutamate could act within the hypothalamus to influence food intake, and that both orexigenic and anorexigenic Neuropeptide genes might contribute directly to these effects.展开更多
High Feed efficiency (FE) in growing heifers has economic importance in dairy, but remains less understood in buffaloes. Feed conversion efficiency is defined as dry matter intake (DMI) per unit body weight gain and i...High Feed efficiency (FE) in growing heifers has economic importance in dairy, but remains less understood in buffaloes. Feed conversion efficiency is defined as dry matter intake (DMI) per unit body weight gain and is determined as residual feed intake (RFI), i.e., the difference between actual and predicted feed intake to gain unit body weight during a feed trial run for 78 days under control feeding. A large variation was identified ranging between -0.42 to 0.35 in growing buffalo heifers (n = 40) of age between 11 to 15 months. An average daily weight gain (ADG) varied between 382.0 and 807.6 g/day when compared with the control-fed heifers at an organized buffalo farm. The whole blood transcriptome data obtained from the selected growing heifers from extremes of estimated high and low RFI efficiency were compared with the reference assembly generated from the transcriptome of multiparous buffaloes (n = 16) of diverse age of maturity, period of regaining post partum cyclicity and level of milk production. Differentially expressed genes (DEGs) were identified using the reference genome of Mediterranean water buffalo. GO: terms (Padj 0.05, FDR 0.05) enriched by annotated DEGs and biological pathways in gene network for RFI efficiency trait were identified. GO: terms specific to pre-transcriptional regulation of nucleus and Chromatin organization under Nucleoplasm, Energy balancing, Immunity, Cell signaling, ROS optimization, ATP generation through the Electron Transport chain and cell proliferation were determined. The study reveals the indicators targeting the actual metabolic changes and molecular functions underlying the feed utilization capacity of buffaloes. Estimated RFI efficiency revealed a large variation over heifers which may lower the DMI even up to 13.6% thus, enabling an increase in ADG up to 16% by involving efficient heifers in breeding plan. The study revealed a scope of high gain by selective breeding for FE in heifers. FE variants catalogued in the study are useful breed-specific RFI markers 展开更多
Two separate experiments were carried out: the first one involved a study of the chemical and some intrinsic feed characteristics of raw cotton stalk( CS) and the efficiency of chemical,biological treatments on the im...Two separate experiments were carried out: the first one involved a study of the chemical and some intrinsic feed characteristics of raw cotton stalk( CS) and the efficiency of chemical,biological treatments on the improvement of the feed value of CS. CS was treated with chemical treatment by mixing 3% Ca( OH)2( CS + Ca),3% urea( CS + U),3% urea +3% Ca( OH)2( CS + Ca + U). Moreover,CS was treated with biological treatment by inoculation of either Lentinus edodes( CS + Po) or Pleurotus ostreatus( CS + Pl) or crushing CS by adding minor ingredient processed into pellet feed,samples from all treatment were analyzed for the nutrients,In vitro dry matter digestibility( INDMD) and free gossypol detoxification rate. The second investigated was the use of crushed or granulation CS as a test feed followed by voluntary feed intake and preference test with sheep. CS + Ca + U treatment can reach up the CP and IVDMD to 9% and 36%,respectively. CS + Po decreased the fiber component and improved CP content and IVDMD. The free gossypol content declined and the free gossypol detoxification rate reached more than 50%. By feeding sheep under the same level of concentrate and corn silage,the voluntary feed intake and daily weight gain in granulation group is higher than in crushing group( P < 0. 05). Crushing CS by adding minor ingredient processed into a pellet feed was best in terms of improved nutritional quality,feed intake and preference,and it was safe and practical method that can be widely used in sheep production systems,to promote the CS feed utilization in similar areas.展开更多
Different amino acids have been shown to affect feed intake when injected directly into the central nervous system of birds. In the present study, we investigated the effects of L-glutamine and L-alanine on feed intak...Different amino acids have been shown to affect feed intake when injected directly into the central nervous system of birds. In the present study, we investigated the effects of L-glutamine and L-alanine on feed intake and the mRNA expression levels of hypothalamic neuropeptides involved in feed intake regulation in broiler chicks. L-Glutamine or L- alanine was intra-cerebroventricularly （ICV） administered to 4-d-old broiler chicks and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotropin releasing factor （CRF）. Our results showed that ICV administration of L-glutamine （0.55 or 5.5 pmol） significantly increased feed intake up to 2 h post-administration period and the hypothalamic NPY mRNA expression levels, while it markedly decreased hypothalamic POMC and CRF mRNA expression levels. In contrast, ICV administration of L-alanine （4 lamol） significantly decreased feed intake for the first 0.5 h post-administration period, and reduced the hypothalamic AgRP mRNA expression levels, while it remarkablely enhanced the mRNA expression levels of MC4R and CRF. These findings suggested that L-glutamine and L-alanine could act within the hypothalamus to influence feed intake in broiler chicks, and that both orexigenic and anorexigenic neuropeptide genes might contribute directly to these effects.展开更多
Background： When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal（HPA） axis. Changes to partitioning...Background： When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal（HPA） axis. Changes to partitioning of energy by an animal are likely to influence the efficiency with which it is utilised. Therefore, this study aimed to determine the physiological stress response to an exogenous adrenocorticotropic hormone（ACTH） challenge in beef heifers divergently ranked on phenotypic residual feed intake（RFI）.Results： Data were collected on 34 Simmental weaning beef heifers the progeny of a well characterized and divergently bred RFI suckler beef herd. Residual feed intake was determined on each animal during the postweaning stage over a 91-day feed intake measurement period during which they were individually offered adlibitum grass silage and 2 kg of concentrate per head once daily. The 12 highest [0.34 kg DM/d] and 12 lowest[-0.48 kg DM/d] ranking animals on RFI were selected for use in this study. For the physiological stress challenge heifers（mean age 605 ± 13 d; mean BW 518 ± 31.4 kg） were fitted aseptically with indwelling jugular catheters to facilitate intensive blood collection. The response of the adrenal cortex to a standardised dose of ACTH（1.98 IU/kg metabolic BW^（0.75）） was examined. Serial blood samples were analysed for plasma cortisol, ACTH and haematology variables. Heifers differing in RFI did not differ（P = 0.59） in ACTH concentrations. Concentration of ACTH peaked（P 〈 0.001） in both RFI groups at 20 min post-ACTH administration, following which concentration declined to baseline levels by 150 min. Similarly, cortisol systemic profile peaked at 60 min and concentrations remained continuously elevated for 150 min. A RFI × time interaction was detected for cortisol concentrations（P = 0.06） with high RFI heifers had a greater cortisol response than Low RFI from 40 min to 150 min relative to ACTH administration. Cortisol response was positively associat展开更多
The present study investigated the effect of partial replacement of soybean meal(Glycine max) with canola meal(CM)(Brassica napus) on the growth performance,haematology,serum biochemistry and meat quality characterist...The present study investigated the effect of partial replacement of soybean meal(Glycine max) with canola meal(CM)(Brassica napus) on the growth performance,haematology,serum biochemistry and meat quality characteristics of female Japanese quails in a 35-day feeding trial.One hundred and forty6-week-old quails 158.28 ± 11.919 g were randomly allocated to 5 isonitrogenous and isoenergetic experimental diets: control diet(CM0; with no CM inclusion); CM0 with 2.5%(CM25),5.0%(CM50),12.5%(CM125) and 17.5%(CM175) soybean meal replaced with CM.Average weekly gain(AWG) and feed conversion efficiency(FCE) were determined.Haematology,serum biochemistry,carcass traits and meat quality parameters were determined at slaughter.Quails fed CM175 had the lowest(P < 0.05) feed intake whereas no differences were observed among the other 4 diets.No dietary effects on AWG,FCE and haematological parameters were observed.Serum biochemical parameters were not influenced by diets with the exception of alkaline phosphatase(ALP),where quails fed CM25 had higher ALP(161.0 U/L) than those fed CM0(37.25 U/L).Quails fed CM25 had the highest chroma(7.39) while those fed CM125 had the lowest(3.58) at 24 h post-slaughter.Diets had no influence(P > 0.05) on cooking losses and peak positive force of quail meat.It was concluded that CM can replace soybean in quail diets up to 12.5% without compromising growth performance,health and quality of meat.Inclusion levels beyond 12.5% promoted poor voluntary feed intake and thus may require feed additives to enhance utilization.展开更多
This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of ...This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of soybean in Zimbabwe due to droughts, inadequate irrigation infrastructure, high input costs, and price controls, the authors identified an alternative to soybean meal in cowpea meal due to its availability and similar amino acid profile to soybean meal. The experiment was carried out at Cold Storage Company in Kadoma. A total of 150 unsexed day-old broiler chicks (Cobb 500) were used. All the birds were brooded in one pen during the first two weeks of age and fed with standard broiler starter mash from National Foods PVT LTD for adaptation. The birds were randomly allocated into five equal groups, each with three replicates and 10 birds per replicate at three weeks of age. Five experimental diets: T1 (100% soybean meal + 0% cowpeas meal), T2 (75% soybean meal + 25% cowpeas meal), T3 (50% soybean meal + 50% cowpeas meal), T4 (25% soybean meal + 75% cowpeas meal) and T5 (0% soybean meal + 100% cowpeas meal) were formulated to be iso-caloric and iso-nitrogenous to meet nutrient requirements of broilers according to NRC (2001). Ration formulation using maize, soybean and cowpea meal as ingredients for broiler starter (21% Crude Protein) and broiler finisher (19% Crude Protein) was done using the Pearson Square Method. Feed intake (g) and weight gain (g) were recorded weekly. Feed Conversion Ratio (FCR) and bioeconomic efficiency were calculated weekly. The experiment lasted for five weeks. The results showed that total Dry Matter Intake for Treatment 1 was the highest (3285 g), and Dry Matter Intakes for Treatments 2, 3 and 4 (3284 g, 3284 g and 3284 g) were not significantly different (P > 0.05) and Dry Matter Intake for Treatment 5 was the lowest (3282 g). Weight gains for Treatments 1 and 2 (2089 g and 2089 g) were not different (P > 0.05), Treatments 3 and 4 (2098 g and 2103 g) were not different (P 展开更多
This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of ...This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of soybean in Zimbabwe due to droughts, inadequate irrigation infrastructure, high input costs, and price controls, the authors identified an alternative to soybean meal in cowpea meal due to its availability and similar amino acid profile to soybean meal. The experiment was carried out at Cold Storage Company in Kadoma. A total of 150 unsexed day-old broiler chicks (Cobb 500) were used. All the birds were brooded in one pen during the first two weeks of age and fed with standard broiler starter mash from National Foods PVT LTD for adaptation. The birds were randomly allocated into five equal groups, each with three replicates and 10 birds per replicate at three weeks of age. Five experimental diets: T1 (100% soybean meal + 0% cowpeas meal), T2 (75% soybean meal + 25% cowpeas meal), T3 (50% soybean meal + 50% cowpeas meal), T4 (25% soybean meal + 75% cowpeas meal) and T5 (0% soybean meal + 100% cowpeas meal) were formulated to be iso-caloric and iso-nitrogenous to meet nutrient requirements of broilers according to NRC (2001). Ration formulation using maize, soybean and cowpea meal as ingredients for broiler starter (21% Crude Protein) and broiler finisher (19% Crude Protein) was done using the Pearson Square Method. Feed intake (g) and weight gain (g) were recorded weekly. Feed Conversion Ratio (FCR) and bioeconomic efficiency were calculated weekly. The experiment lasted for five weeks. The results showed that total Dry Matter Intake for Treatment 1 was the highest (3285 g), and Dry Matter Intakes for Treatments 2, 3 and 4 (3284 g, 3284 g and 3284 g) were not significantly different (P > 0.05) and Dry Matter Intake for Treatment 5 was the lowest (3282 g). Weight gains for Treatments 1 and 2 (2089 g and 2089 g) were not different (P > 0.05), Treatments 3 and 4 (2098 g and 2103 g) were not different (P 展开更多
文摘Two experiments were conducted to investigate the efficacy of benzoic acid on the growth performance of nursery and grower-finisher pigs. A randomized complete block design was used in both experiments with the initial body weight as the blocking factor. There were 3 treatments corresponding to 3 dietary levels of benzoic acid: 0, 0.3%, and 0.5%. In experiment 1, a total of 144 PIC L1050 barrows(initial body weight 7.1 ± 0.6 kg) were used with each treatment replicated 8 times. In experiment 2, a total of 288 PIC L1050 barrows(initial body weight 36.1 ± 3.6 kg) were used with each treatment replicated 16 times.There were 6 barrows in each replicate pen for both experiments. Experiments 1 and 2 lasted 28 and 70 days, respectively. In experiment 1, average daily gain(ADG) of all growth phases increased linearly(P < 0.05) with increasing supplementation of benzoic acid, which led to a linear improvement in average body weight on d 28(P < 0.05). There was also an improvement in feed conversion ratio(FCR) of d 0 to 14(linear effect: P < 0.05) and in average daily feed intake(ADFI) of d 14 to 28 and d 0 to 28(linear effect:P < 0.01). In experiment 2, ADG during d 0 to 35 and d 35 to 70 and average body weight on d 35 improved linearly(P < 0.05) with increasing supplementation of benzoic acid. Average daily gain of d 0 to70 and average body weight on d 70 increased significantly in a both linear and quadratic manner. There was a linear improvement in FCR in all growth phases(P < 0.05). In conclusion, the dietary inclusion of benzoic acid at the supplementation levels of 0.3% and 0.5% significantly improved the growth performance of nursery and grower-finisher pigs in the current study; the nursery pigs responded to the dietary supplementation of benzoic acid up to 0.5% linearly while the grower-finisher pigs achieved the optimal ADG at the calculated supplementation level of 0.36%.
文摘Objective:To investigate the loxic implications of ethanolic stem bark extract of Azadirachta indica(A-indica)at 50,100,200 and 300 mg/kg body weight in Wistar rats.Methods:Fifty male rats of Wistar strains were randomly grouped into five(A-F.)of ten animals each.Animals in Group A(control)were orally administered 1 mL of distilled water on daily basis for 21 days while those in Groups B-E received same volume of the extract corresponding to 50,100,200 and 300mg/kg body weight.Results:The extract did not significantly(P>0.05)alter the levels of albumin,total protein,red blood cells and factors relating to it whereas the white blood cell,platelets,serum triacylglycerol and high-density lipoprotein cholesterol decreased significantly(P<0.05).In contrast,the final body weights,absolute weights of the liver,kidney,lungs and heart as well as their organ-body weight ratios,serum globulins,total and conjugated bilirubin,serum cholesterol,low-density lipoprotein cholesterol and computed atherogenic index increased significantly.The spleen-body weight ratio,alkaline phosphatase,alanine and aspartate transaminases,sodium,potassium,calcium,feed and water intake were altered at specific doses.Conclusions:Overall,the alterations in the biochemical parameters of toxicity have consequential effects on the normal functioning of the organs of the animals.Therefore,the ethanolic extract of A.indica stem bark at the doses of 50,100,200 and 300 mg/kg body weight may not be completely safe as an oral remedy and should be taken with caution if absolutely necessary.
基金supported by National Key Project(2009CB941601)the Joint Funds of the National Natural Science Foundation of China(u0731004)+3 种基金National Natural Science Foundation of China(30871845,30901058 and 30972157)the Natural Science Foundation of Guangdong Province of China(9451064201003790 and 9151064201000056)the Special Fund for Agro-scientific Research in the Public Interest(201003011)Specialized Research Fund for the Doctoral Program of Higher Education of China(20094404120012)
文摘Feed intake control is vital to ensuring optimal nutrition and achieving full potential for growth and development in poultry. The aim of the present study was to investigate the effects of L-leucine, L-glutamate, L-tryptophan and L-arginine on feed intake and the mRNA expression levels of hypothalamic Neuropeptide involved in feed intake regulation in broiler chicks. Leucine, glutamate, tryptophan or arginine was intra-cerebroventricularly （ICV） administrated to 4d-old broiler chicks respectively and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of Neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotrophin releasing factor （CRF）. Our results showed that ICV administration of L-leucine （0.15 or 1.5 μmol） significantly （P〈0.05） increased feed intake up to 2 h post-administration period and elevated both hypothalamic NPY and AgRP mRNA expression levels. In contrast, ICV administration of L-glutamate （1.6 μmol） significantly （P 〈 0.05） decreased feed intake 0.25, 0.5 and 2 h post-injection, and increased hypothalamic CRF and MC4R mRNA expression levels. Meanwhile, both L-tryptophan （10 or 100 μg） and L-arginine （20 or 200 μg） had no significant effect on feed intake. These findings suggested that L-leucine and L-glutamate could act within the hypothalamus to influence food intake, and that both orexigenic and anorexigenic Neuropeptide genes might contribute directly to these effects.
文摘High Feed efficiency (FE) in growing heifers has economic importance in dairy, but remains less understood in buffaloes. Feed conversion efficiency is defined as dry matter intake (DMI) per unit body weight gain and is determined as residual feed intake (RFI), i.e., the difference between actual and predicted feed intake to gain unit body weight during a feed trial run for 78 days under control feeding. A large variation was identified ranging between -0.42 to 0.35 in growing buffalo heifers (n = 40) of age between 11 to 15 months. An average daily weight gain (ADG) varied between 382.0 and 807.6 g/day when compared with the control-fed heifers at an organized buffalo farm. The whole blood transcriptome data obtained from the selected growing heifers from extremes of estimated high and low RFI efficiency were compared with the reference assembly generated from the transcriptome of multiparous buffaloes (n = 16) of diverse age of maturity, period of regaining post partum cyclicity and level of milk production. Differentially expressed genes (DEGs) were identified using the reference genome of Mediterranean water buffalo. GO: terms (Padj 0.05, FDR 0.05) enriched by annotated DEGs and biological pathways in gene network for RFI efficiency trait were identified. GO: terms specific to pre-transcriptional regulation of nucleus and Chromatin organization under Nucleoplasm, Energy balancing, Immunity, Cell signaling, ROS optimization, ATP generation through the Electron Transport chain and cell proliferation were determined. The study reveals the indicators targeting the actual metabolic changes and molecular functions underlying the feed utilization capacity of buffaloes. Estimated RFI efficiency revealed a large variation over heifers which may lower the DMI even up to 13.6% thus, enabling an increase in ADG up to 16% by involving efficient heifers in breeding plan. The study revealed a scope of high gain by selective breeding for FE in heifers. FE variants catalogued in the study are useful breed-specific RFI markers
基金Supported by National Natural Science Foundation of China(31360565)
文摘Two separate experiments were carried out: the first one involved a study of the chemical and some intrinsic feed characteristics of raw cotton stalk( CS) and the efficiency of chemical,biological treatments on the improvement of the feed value of CS. CS was treated with chemical treatment by mixing 3% Ca( OH)2( CS + Ca),3% urea( CS + U),3% urea +3% Ca( OH)2( CS + Ca + U). Moreover,CS was treated with biological treatment by inoculation of either Lentinus edodes( CS + Po) or Pleurotus ostreatus( CS + Pl) or crushing CS by adding minor ingredient processed into pellet feed,samples from all treatment were analyzed for the nutrients,In vitro dry matter digestibility( INDMD) and free gossypol detoxification rate. The second investigated was the use of crushed or granulation CS as a test feed followed by voluntary feed intake and preference test with sheep. CS + Ca + U treatment can reach up the CP and IVDMD to 9% and 36%,respectively. CS + Po decreased the fiber component and improved CP content and IVDMD. The free gossypol content declined and the free gossypol detoxification rate reached more than 50%. By feeding sheep under the same level of concentrate and corn silage,the voluntary feed intake and daily weight gain in granulation group is higher than in crushing group( P < 0. 05). Crushing CS by adding minor ingredient processed into a pellet feed was best in terms of improved nutritional quality,feed intake and preference,and it was safe and practical method that can be widely used in sheep production systems,to promote the CS feed utilization in similar areas.
基金the National Basic Research Program of China (2009CB941601)the Joint Funds of the National Natural Science Foundation of China (u0731004)+3 种基金the National Natural Science Foundation of China(30871845, 30901058 and 30972157)the Natural Science Foundation of Guangdong Province of China(9451064201003790 and 9151064201000056)the National Public Benefit (Agricultural) Research Foundation of China(201003011)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20094404120012)
文摘Different amino acids have been shown to affect feed intake when injected directly into the central nervous system of birds. In the present study, we investigated the effects of L-glutamine and L-alanine on feed intake and the mRNA expression levels of hypothalamic neuropeptides involved in feed intake regulation in broiler chicks. L-Glutamine or L- alanine was intra-cerebroventricularly （ICV） administered to 4-d-old broiler chicks and the feed intake were recorded at various time points. Quantitative PCR was performed to determine the hypothalamic mRNA expression levels of neuropeptide Y （NPY）, agouti related protein （AgRP）, pro-opiomelanocortin （POMC）, melanocortin receptor 4 （MC4R） and corticotropin releasing factor （CRF）. Our results showed that ICV administration of L-glutamine （0.55 or 5.5 pmol） significantly increased feed intake up to 2 h post-administration period and the hypothalamic NPY mRNA expression levels, while it markedly decreased hypothalamic POMC and CRF mRNA expression levels. In contrast, ICV administration of L-alanine （4 lamol） significantly decreased feed intake for the first 0.5 h post-administration period, and reduced the hypothalamic AgRP mRNA expression levels, while it remarkablely enhanced the mRNA expression levels of MC4R and CRF. These findings suggested that L-glutamine and L-alanine could act within the hypothalamus to influence feed intake in broiler chicks, and that both orexigenic and anorexigenic neuropeptide genes might contribute directly to these effects.
文摘Background： When an animal is exposed to a stressor, metabolic rate, energy consumption and utilisation increase primarily through activation of the hypothalamic-pituitary-adrenal（HPA） axis. Changes to partitioning of energy by an animal are likely to influence the efficiency with which it is utilised. Therefore, this study aimed to determine the physiological stress response to an exogenous adrenocorticotropic hormone（ACTH） challenge in beef heifers divergently ranked on phenotypic residual feed intake（RFI）.Results： Data were collected on 34 Simmental weaning beef heifers the progeny of a well characterized and divergently bred RFI suckler beef herd. Residual feed intake was determined on each animal during the postweaning stage over a 91-day feed intake measurement period during which they were individually offered adlibitum grass silage and 2 kg of concentrate per head once daily. The 12 highest [0.34 kg DM/d] and 12 lowest[-0.48 kg DM/d] ranking animals on RFI were selected for use in this study. For the physiological stress challenge heifers（mean age 605 ± 13 d; mean BW 518 ± 31.4 kg） were fitted aseptically with indwelling jugular catheters to facilitate intensive blood collection. The response of the adrenal cortex to a standardised dose of ACTH（1.98 IU/kg metabolic BW^（0.75）） was examined. Serial blood samples were analysed for plasma cortisol, ACTH and haematology variables. Heifers differing in RFI did not differ（P = 0.59） in ACTH concentrations. Concentration of ACTH peaked（P 〈 0.001） in both RFI groups at 20 min post-ACTH administration, following which concentration declined to baseline levels by 150 min. Similarly, cortisol systemic profile peaked at 60 min and concentrations remained continuously elevated for 150 min. A RFI × time interaction was detected for cortisol concentrations（P = 0.06） with high RFI heifers had a greater cortisol response than Low RFI from 40 min to 150 min relative to ACTH administration. Cortisol response was positively associat
基金financial support from Health and Welfare Sector Education and Training Authority towards this projectthe funding received from the North-West University Ph D bursary
文摘The present study investigated the effect of partial replacement of soybean meal(Glycine max) with canola meal(CM)(Brassica napus) on the growth performance,haematology,serum biochemistry and meat quality characteristics of female Japanese quails in a 35-day feeding trial.One hundred and forty6-week-old quails 158.28 ± 11.919 g were randomly allocated to 5 isonitrogenous and isoenergetic experimental diets: control diet(CM0; with no CM inclusion); CM0 with 2.5%(CM25),5.0%(CM50),12.5%(CM125) and 17.5%(CM175) soybean meal replaced with CM.Average weekly gain(AWG) and feed conversion efficiency(FCE) were determined.Haematology,serum biochemistry,carcass traits and meat quality parameters were determined at slaughter.Quails fed CM175 had the lowest(P < 0.05) feed intake whereas no differences were observed among the other 4 diets.No dietary effects on AWG,FCE and haematological parameters were observed.Serum biochemical parameters were not influenced by diets with the exception of alkaline phosphatase(ALP),where quails fed CM25 had higher ALP(161.0 U/L) than those fed CM0(37.25 U/L).Quails fed CM25 had the highest chroma(7.39) while those fed CM125 had the lowest(3.58) at 24 h post-slaughter.Diets had no influence(P > 0.05) on cooking losses and peak positive force of quail meat.It was concluded that CM can replace soybean in quail diets up to 12.5% without compromising growth performance,health and quality of meat.Inclusion levels beyond 12.5% promoted poor voluntary feed intake and thus may require feed additives to enhance utilization.
文摘This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of soybean in Zimbabwe due to droughts, inadequate irrigation infrastructure, high input costs, and price controls, the authors identified an alternative to soybean meal in cowpea meal due to its availability and similar amino acid profile to soybean meal. The experiment was carried out at Cold Storage Company in Kadoma. A total of 150 unsexed day-old broiler chicks (Cobb 500) were used. All the birds were brooded in one pen during the first two weeks of age and fed with standard broiler starter mash from National Foods PVT LTD for adaptation. The birds were randomly allocated into five equal groups, each with three replicates and 10 birds per replicate at three weeks of age. Five experimental diets: T1 (100% soybean meal + 0% cowpeas meal), T2 (75% soybean meal + 25% cowpeas meal), T3 (50% soybean meal + 50% cowpeas meal), T4 (25% soybean meal + 75% cowpeas meal) and T5 (0% soybean meal + 100% cowpeas meal) were formulated to be iso-caloric and iso-nitrogenous to meet nutrient requirements of broilers according to NRC (2001). Ration formulation using maize, soybean and cowpea meal as ingredients for broiler starter (21% Crude Protein) and broiler finisher (19% Crude Protein) was done using the Pearson Square Method. Feed intake (g) and weight gain (g) were recorded weekly. Feed Conversion Ratio (FCR) and bioeconomic efficiency were calculated weekly. The experiment lasted for five weeks. The results showed that total Dry Matter Intake for Treatment 1 was the highest (3285 g), and Dry Matter Intakes for Treatments 2, 3 and 4 (3284 g, 3284 g and 3284 g) were not significantly different (P > 0.05) and Dry Matter Intake for Treatment 5 was the lowest (3282 g). Weight gains for Treatments 1 and 2 (2089 g and 2089 g) were not different (P > 0.05), Treatments 3 and 4 (2098 g and 2103 g) were not different (P
文摘This manuscript explores the biological and economic efficiency of partial dietary substitution of soybean (Glycine max) meal with cowpea (Vigna unguiculata) meal in broiler production. As a result of the shortage of soybean in Zimbabwe due to droughts, inadequate irrigation infrastructure, high input costs, and price controls, the authors identified an alternative to soybean meal in cowpea meal due to its availability and similar amino acid profile to soybean meal. The experiment was carried out at Cold Storage Company in Kadoma. A total of 150 unsexed day-old broiler chicks (Cobb 500) were used. All the birds were brooded in one pen during the first two weeks of age and fed with standard broiler starter mash from National Foods PVT LTD for adaptation. The birds were randomly allocated into five equal groups, each with three replicates and 10 birds per replicate at three weeks of age. Five experimental diets: T1 (100% soybean meal + 0% cowpeas meal), T2 (75% soybean meal + 25% cowpeas meal), T3 (50% soybean meal + 50% cowpeas meal), T4 (25% soybean meal + 75% cowpeas meal) and T5 (0% soybean meal + 100% cowpeas meal) were formulated to be iso-caloric and iso-nitrogenous to meet nutrient requirements of broilers according to NRC (2001). Ration formulation using maize, soybean and cowpea meal as ingredients for broiler starter (21% Crude Protein) and broiler finisher (19% Crude Protein) was done using the Pearson Square Method. Feed intake (g) and weight gain (g) were recorded weekly. Feed Conversion Ratio (FCR) and bioeconomic efficiency were calculated weekly. The experiment lasted for five weeks. The results showed that total Dry Matter Intake for Treatment 1 was the highest (3285 g), and Dry Matter Intakes for Treatments 2, 3 and 4 (3284 g, 3284 g and 3284 g) were not significantly different (P > 0.05) and Dry Matter Intake for Treatment 5 was the lowest (3282 g). Weight gains for Treatments 1 and 2 (2089 g and 2089 g) were not different (P > 0.05), Treatments 3 and 4 (2098 g and 2103 g) were not different (P
