There are negative influences of selection for broiler growth on the reproductive ability of broiler breeder parents. This is mostly due to problems related to excessive body weight, such as an inability to achieve successful cloacal contact during natural mating. There is also an age-related decline in fertility of broiler breeders. In attempts to prolong the fertile period of the breeders, various forms of management techniques have been employed. These include tools such as feed restriction, photoperiod management, spiking, and possibly even using artificial insemination. The first objective of this thesis was to investigate the possible benefits of feeding broiler breeder males diets containing lower crude protein levels, than given to the females, as a means of possibly tempering growth rate or improving semen quality and fertility. There was a definite improvement in the ability of the spermatozoa of the males on a lower crude protein diet to survive in the female reproductive tract. Males that received higher levels of crude protein were at a disadvantage in that fewer males yielded semen in response to abdominal massage. The second objective of this thesis was to assess the possible benefits in semen quality and fertility, when supplementing the male diets with additional vitamin E or Se in the form of Sel-Plex®. No significant effect of treatment was observed on egg fertility or semen quality. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.

Call number: LD2668 .T4 1963 S56 / Master of Science

Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: Two studies were done to determine the distribution rate and efficiency of dietary melamine (MEL) to poultry meat and eggs. The possibility of MEL distribution into meat and eggs after feeding cyromazine (CYR) was also investigated. Five separate diets were formulated for broiler and layer chickens containing graded levels of MEL. In the broiler trial (Experiment 1), a number of 480 day-old Cobb 500 broiler chickens were divided into five treatment groups. Diets contained 0 (CON), 50 (MEL50), 100 (MEL100), 500 (MEL500) mg/kg MEL or 4 mg/kg CYR (CYR4). The duration of the trial was 36 days and breast muscle, kidney and liver samples were harvested on Days 11, 13, 15, 18, 22, 29 and 36 after the start of the feeding and analyzed for MEL. For the duration of the trial, all experimental diets were presented ad libitum and feed intake, weight gain, mortality rate, feed conversion ratio (FCR), protein efficiency rate of birds and the European production efficiency rate were determined. In the layer trial (Experiment 2), 120 Hyline Silver hens (24 weeks of age) were randomly divided into five treatment groups. The treatment diets were the same as for Experiment 1. The duration of the trial was 20 days and layers received the treatment diets for the first 10 days after which the control diet was provided for another 10 days. Feed intake, mortality rate, egg production and egg weights were recorded daily, while live weight was recorded at the beginning and end of the trial. Dietary MEL levels of up to 500 mg/kg did not have any detrimental effect on production parameters for broilers. In the layer trial, feed intake and egg weights were negatively affected by the MEL500 treatment. Dietary MEL was absorbed by broilers and layers and rapidly distributed to the kidneys, livers, muscles and eggs. As the dietary MEL concentration increased from 50 and 100 mg/kg to 500 mg/kg, an increase (P < 0.01) was observed in muscle tissue and egg MEL residue concentrations. Melamine concentration for broilers peaked at 22 days of age and decreased until day of slaughter. The kidneys contained the highest MEL residue levels, compared to other organ tissues, such as muscle and liver. In layer hens, a MEL distribution plateau in eggs was reached between Days 1 and 4 and decreased from Day 7 to 10. The distribution of MEL in eggs was higher to albumin than to the yolk. Upon withdrawal, MEL concentration in these tissues declined to undetectable levels within seven days. No MEL could be detected in meat or eggs when birds received the CYR4 treatment. The distribution efficiency (DEf) of MEL to meat and eggs did not appear to be dose dependant. For meat, the DEf varied between 1.2 and 2.7% and for eggs it varied between 0.7 and 0.8%. / AFRIKAANSE OPSOMMING: Twee studies is uitgevoer om die verspreidings tempo en effektiwiteit van melamien (MEL) na hoender vleis en -eiers te bepaal. Die moontlikheid van MEL verspreiding na vleis en eiers deur die voeding van cyromazien (CYR) is ook ondersoek. Vyf aparte diëte is geformuleer vir braaikuikens en lê-henne wat verskillende MEL insluitings vlakke bevat het. Vir die braaikuiken proef (Eksperiment 1), is 480 dag oud Cobb 500 braaikuikens ingedeel in vyf behandelings groepe. Diëte het 0 (CON), 50 (MEL50), 100 (MEL100), 500 (MEL500) mg/kg MEL en 4 mg/kg CYR (CYR4) bevat. Die tydsduur van hierdie proef was 36 dae en bors-, spier-, nier- en lewer monsters is ingesamel op Dae 11, 13, 15, 18, 22, 29 en 36 wat geëvalueer is vir MEL. Tydens die verloop van die proef is alle eksperimentele diëte ad libitum gevoer en voerinname, massa toename, mortaliteit, voeromsettings verhouding, proteïen effektiwiteits tempo asook die Europese produksie effektiwiteits tempo is bepaal. Vir die lê-hen proef (Eksperiment 2), is 120 Hyline Silver henne (24 weke oud) ewekansig verdeel in vyf behandelings groepe. Die behandelings diëte het dieselfde MEL en CYR konsentrasies bevat as Eksperiment 1. Die tydsduur van hierdie proef was altesaam 20 dae waarvan henne behandelings diëte vir die eerste 10 dae ontvang het, waarna henne vir die daarop volgende 10 dae ‘n kontrole dieët wat 0 mg/kg MEL bevat gevoer is. Voerinname, mortaliteit, eier produksie en eier gewig is daagliks opgeteken, terwyl lewende massa aan die begin en einde van die proef gemeet is. Melamien dieët vlakke tot 500 mg/kg het geen negatiewe effek op braaikuiken produksie parameters gehad nie. Vir lê-henne, is slegs voerinname en eier gewig negatief beïnvloed vir MEL500. Melamien is na inname geabsorbeer deur braaikuikens en lê-henne en het vinnig versprei na die niere, lewer, spiere en eiers. Soos die MEL vlakke van die behandelings diëte toegeneem het van 50 en 100 mg/kg na 500 mg/kg, het ‘n beduidende (P < 0.01) toename in spierweefsel en eier MEL residu konsentrasies voorgekom. Melamien konsentrasies vir braaikuikens het gepiek op 22 dae en geleidelik afgeneem tot op dag 36. In lê-henne het ‘n MEL verspreidings platu in eiers plaasgevind tussen Dag 1 en 4 en geleidelik afgeneem tydens Dag 7 en 10. Die niere het die hoogste MEL residu vlakke bevat in vergelyking met die lewer- en spierweefsels. Die verspreiding van MEL in eiers was hoër na die albumien as na die dooier. Tydens onttrekking het die MEL konsentrasie vlakke in hierdie weefsels in so ‘n mate afgeneem dat dit onbespeurbaar was binne sewe dae. Geen MEL kon in vleis- en eiermonsters gemeet word vir CYR4 nie. Die verspreidings doeltreffendheid (DEf) van MEL na vleis en eiers was nie dosis afhanklik nie. Vir vleis het die DEf gevarieër tussen 1.2 en 2.7% en vir eiers tussen 0.7 en 0.8%.

Thesis (MScAgric)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The use of phytase enzymes to liberate phosphorus and other phytate bound nutrients in monogastric animal diets are becoming common practice and several commercial phytase enzymes are available on the market. Phytase manufacturers supply nutritionists with matrix values for the specific phytase, enabling nutritionists to effectively decrease the dietary concentrations of phosphorus and nutrients during diet formulation. A 32 day experiment was conducted with 5120 broiler chicks fed diets supplemented with different commercial phytase enzymes (1000 FYT or 1500 FYT HiPhos/kg diet, 1500 FYT Ronozyme/kg diet, 500 FTU Natuphos/kg diet or 500 FTU Phyzyme/kg diet) at levels recommended by the manufacturers and with similar phosphorus equivalence. The nutrient content of the diets supplemented with 500 FTU Natuphos, 500 FTU Phyzyme 1500 Ronozyme and 1000 FYT HiPhos were reduced according to the matrix values of 1000 FYT/kg HiPhos, whilst the diet supplemented with 1500 FYT HiPhos /kg diet was reduced according to the matrix values 1500 FYT HiPhos. The objectives of this study were threefold: (i) to confirm the matrix value for a newly developed phytase (HiPhos, DSM Nutritional Products, Basel, Switzerland), at two different inclusion levels, using weight gain and bone parameters of broilers as response criteria; (ii) to compare production and bone parameters of broilers reared on three different commercial phytases to broilers reared on HiPhos (iii) to investigate the effect that supplementation of these four phytases has on water intake, carcass characteristics, organ weights and gastrointestinal tract morphology of broilers. The matrix values for 1500 FYT HiPhos were confirmed by using live weight gain as response criteria, but results for bone parameters were insufficient in confirming the matrix values. The matrix values for 1000 FYT HiPhos were confirmed by the results for tibia weight and tibia strength, but results for weight gain were insufficient to confirm the values. The matrix values for 1000 FYT HiPhos and 1500 FYT HiPhos could not be confirmed nor disproved, nevertheless results from the current trial proved diets supplemented with HiPhos to be more economically viable when compared to the standard commercial broiler diet. Total feed and water intake were not influenced by phytase supplementation. Production parameters (live weight, feed intake, feed conversion ratio, European production efficiency factor and average daily gain) and bone parameters (tibia strength, fat free tibia weight, fat free tibia ash and mineral content) did not differ between phytase treatments and therefore all the commercial phytases were equally effective to the HiPhos phytase. Furthermore, results indicate that the investigated phytases had no effect on internal organ weight or gastrointestinal tract morphology in broilers. Overall the results obtained from the study indicate that the use of phytase as feed additive has no negative effects on growth performance, carcass characteristics or bone parameters. No major differences for the production and bone parameters were observed between broilers supplemented with different phytases. Therefore the costs of these phytases can be the determining factor when nutritionists decide which commercial phytase to use. / AFRIKAANSE OPSOMMING: Die gebruik van fitase ensieme in die diëte van enkelmaagdiere om fitaat-gebonde fosfor en voedingstowwe vry te stel, word al hoe meer algemeen in die bedryf en verskeie kommersiële fitase ensieme is in die mark beskikbaar. Die ensiemvervaardigers verskaf die fitases se matryswaardes aan voedingskundiges wat hul in staat stel om die fosfor- en nutrientvlakke in die dieet effektief te verminder. ´n Studie met 5120 braaikuikens was vir 32 dae uitgevoer. Die braaikuiken diëte was met verskillende kommersiële fitase ensieme (1000 FYT & 1500 FYT HiPhos/kg dieet, 1500 FYT Ronozyme/kg dieet, 500 FTU Natuphos/kg dieet of 500 FTU Phyzyme/kg dieet) aangevul. Die nutrientvlakke van die diëte wat met fitase aangevul was, was verminder volgens die matryswaardes van 1000 FYT of 1500 FYT HiPhos fitase. Die doelstellings van hierdie studie was drievoudig: (i) om die matryswaardes van ´n nuwe fitase (HiPhos, DSM Nutritional Products, Basel, Switzerland) by twee verskillende insluitingsvlakke te bevestig deur massa toename en been parameters as reaksie maatstawwe te gebruik (ii) om produksie- en been parameters van braaikuikens, wat een van drie kommersiële fitase ensieme as voerbymiddel ontvang het, met dié van braaikuikens wat die nuwe ensiem gevoer was te vergelyk (iii) om die effek wat fitase op water inname, karkaseienskappe, orgaan massas en spysverteringskanaal morfologie het te bestudeer. Die matryswaardes vir 1500 FYT HiPhos was bevestig deur lewendige massa toename as respons kriteria te gebruik, maar resultate vir die been parameters was onvoldoende om die matryswaardes te bevestig. Die matryswaardes vir 1000 FYT HiPhos was slegs bevestig deur die resultate vir die breeksterktes van die tibias, maar resultate vir massa toename was onvoldoende om die matryswaardes te bevestig. Dus kon die matryswaardes vir die HiPhos fitase nie bevestig of verkeerd bewys word nie. Desondanks het die resultate in die huidige proef bewys dat diëte wat met HiPhos aangevul was meer ekonomies as die kommersiële braaikuiken dieet is. Totale voer- en water-inname was nie deur die aanvulling van fitase beïnvloed nie. Produksie parameters (lewendige massa, voeromset, die Europese produksie doeltreffendheids faktor, gemiddelde daaglikse toename) en been parameters (tibia breeksterkte, vet vrye tibia massa, vet vrye tibia as en mineraal-inhoud) het nie verskil tussen die fitase behandelings nie en dus was al die kommersiële fitases ewe effektief. Vanuit die studie is getoon dat die gebruik van fitase as ´n voerbymiddels geen negatiewe effek op groei, karkas eienskappe of been parameters het nie en dat fitase ook nie die orgaan gewigte of die spysverteringskanaal morfologie van braaikuikens beïnvloed nie. Geen groot verskille in produksieen been parameters was waargeneem tussen hoenders wat verskillende fitases as voerbymiddel ontvang het nie, daarom kan die koste van die ensiem die bepalende faktor wees as voedingkundiges die keuse maak tussen hierdie kommersiele fitases.

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Thesis (MA. Agric. (Animal Production)) -- University of Limpopo, 2014 / This study determined the effect of carrot meal supplementation on productivity and carcass characteristics of Arbor acres broiler chickens aged one to six weeks. Experiment I determined the effect of carrot meal supplementation on productivity of Arbor acre broiler chicks aged one to 21 days. Two hundred unsexed Arbor acre broiler chickens were randomly assigned to five treatments with five replicates, each replicate having ten birds. A completely randomized design was used in the first experiment. The treatments were 0 (UA0), 20 (AU20), 50 (AU50), 75 (AU75) or 100 (AU100) g of carrot meal supplementation per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged one to 21 days. Linear equations were used to determine relationships between carrot meal supplementation and productivity variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation, however, improved (P<0.05) metabolisable energy intake and nitrogen retention of the chickens. Dietary metabolisable energy intake and nitrogen retention of the chickens were optimized at different carrot meal supplementation levels of 40.5 and 53.57 g/kg DM feed, respectively. No chicken deaths were recorded. Experiment II determined the effect of carrot meal supplementation on productivity and carcass characteristics of female Arbor acre broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with five replicates, each having 10 birds, in a completely randomized design. The supplementation levels were 0 (FA0), 20 (FA20), 50 (FA50), 75 (FA75), or 100 (FA100) g of carrot meal per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention of broiler chickens aged 22 to 42 days. Linear equations were used to determine relationships between carrot meal supplementation and production variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and carcass parts of female Arbor acre broiler chickens aged 22 to 42 days. Carrot meal supplementation improved (P<0.05) feed intake, feed conversion ratio, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged vi 22 to 42 days. Dietary feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention were optimized at different dietary carrot meal supplementation levels of 52.8, 63.8, 38.0, 42.0 and 44.3 g/kg DM feed, respectively. Dietary carrot meal supplementation had no effect (P>0.05) on tenderness and flavour of female Arbor acre broiler meat. Broiler chickens on diets supplemented with 20, 50 or 100 g of carrot meal per kg DM feed produced meat with better (P<0.05) juiciness values than those of meat from chickens not supplemented with dietary carrot meal and those supplemented with 75 g/kg DM feed. There was a positive relationship between carrot meal supplementation and chicken meat juiciness. It is concluded that carrot meal supplementation improved (P<0.05) metabolisable energy intake and nitrogen retention of unsexed Arbor acre broiler chickens aged one to 21 days. However, carrot meal supplementation had no effect (P>0.05) on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation improved (P<0.05) intake, feed conversion ratio, metabolisable energy and nitrogen retention of female Arbor acre broiler chickens aged 22 to 42 days. However, carrot meal supplementation did not (P>0.05) improve growth rate and live weights of the chickens.

Thesis (MSc. Agriculture (Animal Production)) -- University of Limpopo, 2014 / Two experiments were conducted to determine the effect of moringa seed meal supplementation on productivity and carcass characteristics of Ross 308 broiler chickens. The first experiment determined the effect of moringa seed meal supplementation on productivity of Ross 308 broiler chickens aged one to 21 days. Two hundred and fifty unsexed day-old Ross 308 broiler chicks were randomly allocated to five dietary treatments, replicated five times, and each replication having 10 chickens. A completely randomized design was used. The chickens were fed on a grower diet supplemented with 0 (M0), 5 (M5), 10 (M10), 15 (M15) and 20 (M20) g of moringa seed meal/bird/day. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, metabolisable energy intake, nitrogen retention, feed conversion ratio and live weight of unsexed Ross 308 broiler chickens. Moringa seed meal supplementation improved (P<0.05) growth rates of unsexed Ross 308 broiler chickens aged one to 21 days. A moringa seed meal supplementation level of 13.3 g/kg DM feed optimized growth rate of Ross 308 broiler chickens aged one to 21 days. The second experiment determined the effect of moringa seed meal supplementation on productivity and carcass characteristics of female Ross 308 broiler chickens aged 22 to 42 days. The chickens weighing 558 ± 10 g/bird were randomly allocated to five treatments with five replications having 10 birds. The chickens, aged 21 days, were allocated to the treatments in a completely randomized design. The chickens were fed on a grower diet supplemented with 0 (FM0), 5 (FM5), 10 (FM10), 15 (FM15) and 20 (FM20) g of moringa seed meal per kg DM. Moringa seed meal supplementation had no effect (P>0.05) on feed intake, growth rate, feed conversion ratio, live weight, metabolisable energy intake, carcass weight, breast meat weight, abdominal fat pad weight, liver weight, heart weight, thigh weight, meat flavour, juiciness and tenderness of female Ross 308 broiler chickens. However, moringa seed meal supplementation improved (P<0.05) nitrogen retention and gizzard weights of female Ross 308 broiler chickens. vi It was concluded that moringa seed meal supplementation improved growth rate of unsexed Ross 308 broiler chickens aged one to 21 days. Similarly, moringa seed meal supplementation increased nitrogen retention and gizzard weights of female Ross 308 broiler chickens aged 22 to 42 days.

Thesis (MA. Agricultural Management (Animal Production)) -- University of Limpopo, 2014 / This study determined the effect of carrot meal supplementation on productivity and carcass characteristics of Arbor acres broiler chickens aged one to six weeks. Experiment I determined the effect of carrot meal supplementation on productivity of Arbor acre broiler chicks aged one to 21 days. Two hundred unsexed Arbor acre broiler chickens were randomly assigned to five treatments with five replicates, each replicate having ten birds. A completely randomized design was used in the first experiment. The treatments were 0 (UA0), 20 (AU20), 50 (AU50), 75 (AU75) or 100 (AU100) g of carrot meal supplementation per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged one to 21 days. Linear equations were used to determine relationships between carrot meal supplementation and productivity variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation, however, improved (P<0.05) metabolisable energy intake and nitrogen retention of the chickens. Dietary metabolisable energy intake and nitrogen retention of the chickens were optimized at different carrot meal supplementation levels of 40.5 and 53.57 g/kg DM feed, respectively. No chicken deaths were recorded. Experiment II determined the effect of carrot meal supplementation on productivity and carcass characteristics of female Arbor acre broiler chickens aged 22 to 42 days. The chickens were randomly allocated to five treatments with five replicates, each having 10 birds, in a completely randomized design. The supplementation levels were 0 (FA0), 20 (FA20), 50 (FA50), 75 (FA75), or 100 (FA100) g of carrot meal per kg DM feed. Quadratic equations were used to determine levels of carrot meal supplementation for optimal feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention of broiler chickens aged 22 to 42 days. Linear equations were used to determine relationships between carrot meal supplementation and production variables. Dietary carrot meal supplementation had no (P>0.05) effect on growth rate, live weight and carcass parts of female Arbor acre broiler chickens aged 22 to 42 days. Carrot meal supplementation improved (P<0.05) feed intake, feed conversion ratio, metabolisable energy intake and nitrogen retention of Arbor acre broiler chickens aged vi 22 to 42 days. Dietary feed intake, feed conversion ratio, live weight, metabolisable energy intake and nitrogen retention were optimized at different dietary carrot meal supplementation levels of 52.8, 63.8, 38.0, 42.0 and 44.3 g/kg DM feed, respectively. Dietary carrot meal supplementation had no effect (P>0.05) on tenderness and flavour of female Arbor acre broiler meat. Broiler chickens on diets supplemented with 20, 50 or 100 g of carrot meal per kg DM feed produced meat with better (P<0.05) juiciness values than those of meat from chickens not supplemented with dietary carrot meal and those supplemented with 75 g/kg DM feed. There was a positive relationship between carrot meal supplementation and chicken meat juiciness. It is concluded that carrot meal supplementation improved (P<0.05) metabolisable energy intake and nitrogen retention of unsexed Arbor acre broiler chickens aged one to 21 days. However, carrot meal supplementation had no effect (P>0.05) on growth rate, live weight and feed conversion ratio of unsexed Arbor acre broiler chickens aged one to 21 days. Carrot meal supplementation improved (P<0.05) intake, feed conversion ratio, metabolisable energy and nitrogen retention of female Arbor acre broiler chickens aged 22 to 42 days. However, carrot meal supplementation did not (P>0.05) improve growth rate and live weights of the chickens.